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Willy Tarreau6a06a402007-07-15 20:15:28 +02001 ----------------------
Willy Tarreau8317b282014-04-23 01:49:41 +02002 HAProxy
Willy Tarreau6a06a402007-07-15 20:15:28 +02003 Configuration Manual
4 ----------------------
Willy Tarreau1db55792020-11-05 17:20:35 +01005 version 2.4
Willy Tarreau6a06a402007-07-15 20:15:28 +02006 willy tarreau
Willy Tarreauacb1d0b2021-09-07 16:17:15 +02007 2021/09/07
Willy Tarreau6a06a402007-07-15 20:15:28 +02008
9
10This document covers the configuration language as implemented in the version
Davor Ocelice9ed2812017-12-25 17:49:28 +010011specified above. It does not provide any hints, examples, or advice. For such
Willy Tarreau0ba27502007-12-24 16:55:16 +010012documentation, please refer to the Reference Manual or the Architecture Manual.
Davor Ocelice9ed2812017-12-25 17:49:28 +010013The summary below is meant to help you find sections by name and navigate
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014through the document.
Willy Tarreau6a06a402007-07-15 20:15:28 +020015
Willy Tarreauc57f0e22009-05-10 13:12:33 +020016Note to documentation contributors :
Jamie Gloudonaaa21002012-08-25 00:18:33 -040017 This document is formatted with 80 columns per line, with even number of
Willy Tarreauc57f0e22009-05-10 13:12:33 +020018 spaces for indentation and without tabs. Please follow these rules strictly
19 so that it remains easily printable everywhere. If a line needs to be
20 printed verbatim and does not fit, please end each line with a backslash
Willy Tarreau62a36c42010-08-17 15:53:10 +020021 ('\') and continue on next line, indented by two characters. It is also
Davor Ocelice9ed2812017-12-25 17:49:28 +010022 sometimes useful to prefix all output lines (logs, console outputs) with 3
23 closing angle brackets ('>>>') in order to emphasize the difference between
24 inputs and outputs when they may be ambiguous. If you add sections,
Willy Tarreau62a36c42010-08-17 15:53:10 +020025 please update the summary below for easier searching.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020026
27
28Summary
29-------
30
311. Quick reminder about HTTP
321.1. The HTTP transaction model
331.2. HTTP request
Davor Ocelice9ed2812017-12-25 17:49:28 +0100341.2.1. The request line
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200351.2.2. The request headers
361.3. HTTP response
Davor Ocelice9ed2812017-12-25 17:49:28 +0100371.3.1. The response line
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200381.3.2. The response headers
39
402. Configuring HAProxy
412.1. Configuration file format
William Lallemandf9873ba2015-05-05 17:37:14 +0200422.2. Quoting and escaping
William Lallemandb2f07452015-05-12 14:27:13 +0200432.3. Environment variables
Willy Tarreau4b103022021-02-12 17:59:10 +0100442.4. Conditional blocks
452.5. Time format
462.6. Examples
Willy Tarreauc57f0e22009-05-10 13:12:33 +020047
483. Global parameters
493.1. Process management and security
503.2. Performance tuning
513.3. Debugging
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +0100523.4. Userlists
Cyril Bontédc4d9032012-04-08 21:57:39 +0200533.5. Peers
Cyril Bonté307ee1e2015-09-28 23:16:06 +0200543.6. Mailers
William Lallemandc9515522019-06-12 16:32:11 +0200553.7. Programs
Christopher Faulet76edc0f2020-01-13 15:52:01 +0100563.8. HTTP-errors
Emeric Brun99c453d2020-05-25 15:01:04 +0200573.9. Rings
William Lallemand0217b7b2020-11-18 10:41:24 +0100583.10. Log forwarding
Willy Tarreauc57f0e22009-05-10 13:12:33 +020059
604. Proxies
614.1. Proxy keywords matrix
624.2. Alphabetically sorted keywords reference
63
Davor Ocelice9ed2812017-12-25 17:49:28 +0100645. Bind and server options
Willy Tarreau086fbf52012-09-24 20:34:51 +0200655.1. Bind options
665.2. Server and default-server options
Baptiste Assmann1fa66662015-04-14 00:28:47 +0200675.3. Server DNS resolution
685.3.1. Global overview
695.3.2. The resolvers section
Willy Tarreauc57f0e22009-05-10 13:12:33 +020070
Julien Pivotto6ccee412019-11-27 15:49:54 +0100716. Cache
726.1. Limitation
736.2. Setup
746.2.1. Cache section
756.2.2. Proxy section
76
Willy Tarreau74ca5042013-06-11 23:12:07 +0200777. Using ACLs and fetching samples
787.1. ACL basics
797.1.1. Matching booleans
807.1.2. Matching integers
817.1.3. Matching strings
827.1.4. Matching regular expressions (regexes)
837.1.5. Matching arbitrary data blocks
847.1.6. Matching IPv4 and IPv6 addresses
857.2. Using ACLs to form conditions
867.3. Fetching samples
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200877.3.1. Converters
887.3.2. Fetching samples from internal states
897.3.3. Fetching samples at Layer 4
907.3.4. Fetching samples at Layer 5
917.3.5. Fetching samples from buffer contents (Layer 6)
927.3.6. Fetching HTTP samples (Layer 7)
Christopher Faulete596d182020-05-05 17:46:34 +0200937.3.7. Fetching samples for developers
Willy Tarreau74ca5042013-06-11 23:12:07 +0200947.4. Pre-defined ACLs
Willy Tarreauc57f0e22009-05-10 13:12:33 +020095
968. Logging
978.1. Log levels
988.2. Log formats
998.2.1. Default log format
1008.2.2. TCP log format
1018.2.3. HTTP log format
William Lallemand48940402012-01-30 16:47:22 +01001028.2.4. Custom log format
Willy Tarreau5f51e1a2012-12-03 18:40:10 +01001038.2.5. Error log format
Willy Tarreauc57f0e22009-05-10 13:12:33 +02001048.3. Advanced logging options
1058.3.1. Disabling logging of external tests
1068.3.2. Logging before waiting for the session to terminate
1078.3.3. Raising log level upon errors
1088.3.4. Disabling logging of successful connections
1098.4. Timing events
1108.5. Session state at disconnection
1118.6. Non-printable characters
1128.7. Capturing HTTP cookies
1138.8. Capturing HTTP headers
1148.9. Examples of logs
115
Christopher Fauletc3fe5332016-04-07 15:30:10 +02001169. Supported filters
1179.1. Trace
1189.2. HTTP compression
Christopher Fauletf7e4e7e2016-10-27 22:29:49 +02001199.3. Stream Processing Offload Engine (SPOE)
Christopher Faulet99a17a22018-12-11 09:18:27 +01001209.4. Cache
Christopher Fauletb30b3102019-09-12 23:03:09 +02001219.5. fcgi-app
Miroslav Zagoracdc32cd92020-12-13 18:32:57 +01001229.6. OpenTracing
Christopher Fauletc3fe5332016-04-07 15:30:10 +0200123
Christopher Fauletb30b3102019-09-12 23:03:09 +020012410. FastCGI applications
12510.1. Setup
12610.1.1. Fcgi-app section
12710.1.2. Proxy section
12810.1.3. Example
12910.2. Default parameters
13010.3. Limitations
131
Emeric Brunce325c42021-04-02 17:05:09 +020013211. Address formats
13311.1. Address family prefixes
13411.2. Socket type prefixes
13511.3. Protocol prefixes
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200136
1371. Quick reminder about HTTP
138----------------------------
139
Davor Ocelice9ed2812017-12-25 17:49:28 +0100140When HAProxy is running in HTTP mode, both the request and the response are
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200141fully analyzed and indexed, thus it becomes possible to build matching criteria
142on almost anything found in the contents.
143
144However, it is important to understand how HTTP requests and responses are
145formed, and how HAProxy decomposes them. It will then become easier to write
146correct rules and to debug existing configurations.
147
148
1491.1. The HTTP transaction model
150-------------------------------
151
152The HTTP protocol is transaction-driven. This means that each request will lead
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +0100153to one and only one response. Traditionally, a TCP connection is established
Davor Ocelice9ed2812017-12-25 17:49:28 +0100154from the client to the server, a request is sent by the client through the
155connection, the server responds, and the connection is closed. A new request
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200156will involve a new connection :
157
158 [CON1] [REQ1] ... [RESP1] [CLO1] [CON2] [REQ2] ... [RESP2] [CLO2] ...
159
160In this mode, called the "HTTP close" mode, there are as many connection
161establishments as there are HTTP transactions. Since the connection is closed
162by the server after the response, the client does not need to know the content
163length.
164
165Due to the transactional nature of the protocol, it was possible to improve it
166to avoid closing a connection between two subsequent transactions. In this mode
167however, it is mandatory that the server indicates the content length for each
168response so that the client does not wait indefinitely. For this, a special
169header is used: "Content-length". This mode is called the "keep-alive" mode :
170
171 [CON] [REQ1] ... [RESP1] [REQ2] ... [RESP2] [CLO] ...
172
173Its advantages are a reduced latency between transactions, and less processing
174power required on the server side. It is generally better than the close mode,
175but not always because the clients often limit their concurrent connections to
Patrick Mezard9ec2ec42010-06-12 17:02:45 +0200176a smaller value.
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200177
Willy Tarreau95c4e142017-11-26 12:18:55 +0100178Another improvement in the communications is the pipelining mode. It still uses
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200179keep-alive, but the client does not wait for the first response to send the
180second request. This is useful for fetching large number of images composing a
181page :
182
183 [CON] [REQ1] [REQ2] ... [RESP1] [RESP2] [CLO] ...
184
185This can obviously have a tremendous benefit on performance because the network
186latency is eliminated between subsequent requests. Many HTTP agents do not
187correctly support pipelining since there is no way to associate a response with
188the corresponding request in HTTP. For this reason, it is mandatory for the
Cyril Bonté78caf842010-03-10 22:41:43 +0100189server to reply in the exact same order as the requests were received.
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200190
Willy Tarreau95c4e142017-11-26 12:18:55 +0100191The next improvement is the multiplexed mode, as implemented in HTTP/2. This
192time, each transaction is assigned a single stream identifier, and all streams
193are multiplexed over an existing connection. Many requests can be sent in
194parallel by the client, and responses can arrive in any order since they also
195carry the stream identifier.
196
Willy Tarreau70dffda2014-01-30 03:07:23 +0100197By default HAProxy operates in keep-alive mode with regards to persistent
198connections: for each connection it processes each request and response, and
199leaves the connection idle on both sides between the end of a response and the
Willy Tarreau95c4e142017-11-26 12:18:55 +0100200start of a new request. When it receives HTTP/2 connections from a client, it
201processes all the requests in parallel and leaves the connection idling,
202waiting for new requests, just as if it was a keep-alive HTTP connection.
Patrick Mezard9ec2ec42010-06-12 17:02:45 +0200203
Christopher Faulet315b39c2018-09-21 16:26:19 +0200204HAProxy supports 4 connection modes :
Willy Tarreau70dffda2014-01-30 03:07:23 +0100205 - keep alive : all requests and responses are processed (default)
206 - tunnel : only the first request and response are processed,
Christopher Faulet6c9bbb22019-03-26 21:37:23 +0100207 everything else is forwarded with no analysis (deprecated).
Willy Tarreau70dffda2014-01-30 03:07:23 +0100208 - server close : the server-facing connection is closed after the response.
Christopher Faulet315b39c2018-09-21 16:26:19 +0200209 - close : the connection is actively closed after end of response.
Willy Tarreau70dffda2014-01-30 03:07:23 +0100210
Willy Tarreau95c4e142017-11-26 12:18:55 +0100211
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200212
2131.2. HTTP request
214-----------------
215
216First, let's consider this HTTP request :
217
218 Line Contents
Willy Tarreaud72758d2010-01-12 10:42:19 +0100219 number
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200220 1 GET /serv/login.php?lang=en&profile=2 HTTP/1.1
221 2 Host: www.mydomain.com
222 3 User-agent: my small browser
223 4 Accept: image/jpeg, image/gif
224 5 Accept: image/png
225
226
2271.2.1. The Request line
228-----------------------
229
230Line 1 is the "request line". It is always composed of 3 fields :
231
232 - a METHOD : GET
233 - a URI : /serv/login.php?lang=en&profile=2
234 - a version tag : HTTP/1.1
235
236All of them are delimited by what the standard calls LWS (linear white spaces),
237which are commonly spaces, but can also be tabs or line feeds/carriage returns
238followed by spaces/tabs. The method itself cannot contain any colon (':') and
239is limited to alphabetic letters. All those various combinations make it
240desirable that HAProxy performs the splitting itself rather than leaving it to
241the user to write a complex or inaccurate regular expression.
242
243The URI itself can have several forms :
244
245 - A "relative URI" :
246
247 /serv/login.php?lang=en&profile=2
248
249 It is a complete URL without the host part. This is generally what is
250 received by servers, reverse proxies and transparent proxies.
251
252 - An "absolute URI", also called a "URL" :
253
254 http://192.168.0.12:8080/serv/login.php?lang=en&profile=2
255
256 It is composed of a "scheme" (the protocol name followed by '://'), a host
257 name or address, optionally a colon (':') followed by a port number, then
258 a relative URI beginning at the first slash ('/') after the address part.
259 This is generally what proxies receive, but a server supporting HTTP/1.1
260 must accept this form too.
261
262 - a star ('*') : this form is only accepted in association with the OPTIONS
263 method and is not relayable. It is used to inquiry a next hop's
264 capabilities.
Willy Tarreaud72758d2010-01-12 10:42:19 +0100265
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200266 - an address:port combination : 192.168.0.12:80
267 This is used with the CONNECT method, which is used to establish TCP
268 tunnels through HTTP proxies, generally for HTTPS, but sometimes for
269 other protocols too.
270
271In a relative URI, two sub-parts are identified. The part before the question
272mark is called the "path". It is typically the relative path to static objects
273on the server. The part after the question mark is called the "query string".
274It is mostly used with GET requests sent to dynamic scripts and is very
275specific to the language, framework or application in use.
276
Willy Tarreau95c4e142017-11-26 12:18:55 +0100277HTTP/2 doesn't convey a version information with the request, so the version is
Davor Ocelice9ed2812017-12-25 17:49:28 +0100278assumed to be the same as the one of the underlying protocol (i.e. "HTTP/2").
Willy Tarreau95c4e142017-11-26 12:18:55 +0100279
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200280
2811.2.2. The request headers
282--------------------------
283
284The headers start at the second line. They are composed of a name at the
285beginning of the line, immediately followed by a colon (':'). Traditionally,
286an LWS is added after the colon but that's not required. Then come the values.
287Multiple identical headers may be folded into one single line, delimiting the
288values with commas, provided that their order is respected. This is commonly
289encountered in the "Cookie:" field. A header may span over multiple lines if
290the subsequent lines begin with an LWS. In the example in 1.2, lines 4 and 5
291define a total of 3 values for the "Accept:" header.
292
Davor Ocelice9ed2812017-12-25 17:49:28 +0100293Contrary to a common misconception, header names are not case-sensitive, and
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200294their values are not either if they refer to other header names (such as the
Willy Tarreau95c4e142017-11-26 12:18:55 +0100295"Connection:" header). In HTTP/2, header names are always sent in lower case,
Willy Tarreau253c2512020-07-07 15:55:23 +0200296as can be seen when running in debug mode. Internally, all header names are
297normalized to lower case so that HTTP/1.x and HTTP/2 use the exact same
298representation, and they are sent as-is on the other side. This explains why an
299HTTP/1.x request typed with camel case is delivered in lower case.
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200300
301The end of the headers is indicated by the first empty line. People often say
302that it's a double line feed, which is not exact, even if a double line feed
303is one valid form of empty line.
304
305Fortunately, HAProxy takes care of all these complex combinations when indexing
306headers, checking values and counting them, so there is no reason to worry
307about the way they could be written, but it is important not to accuse an
308application of being buggy if it does unusual, valid things.
309
310Important note:
Lukas Tribus23953682017-04-28 13:24:30 +0000311 As suggested by RFC7231, HAProxy normalizes headers by replacing line breaks
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200312 in the middle of headers by LWS in order to join multi-line headers. This
313 is necessary for proper analysis and helps less capable HTTP parsers to work
314 correctly and not to be fooled by such complex constructs.
315
316
3171.3. HTTP response
318------------------
319
320An HTTP response looks very much like an HTTP request. Both are called HTTP
321messages. Let's consider this HTTP response :
322
323 Line Contents
Willy Tarreaud72758d2010-01-12 10:42:19 +0100324 number
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200325 1 HTTP/1.1 200 OK
326 2 Content-length: 350
327 3 Content-Type: text/html
328
Willy Tarreau816b9792009-09-15 21:25:21 +0200329As a special case, HTTP supports so called "Informational responses" as status
330codes 1xx. These messages are special in that they don't convey any part of the
331response, they're just used as sort of a signaling message to ask a client to
Willy Tarreau5843d1a2010-02-01 15:13:32 +0100332continue to post its request for instance. In the case of a status 100 response
333the requested information will be carried by the next non-100 response message
334following the informational one. This implies that multiple responses may be
335sent to a single request, and that this only works when keep-alive is enabled
336(1xx messages are HTTP/1.1 only). HAProxy handles these messages and is able to
337correctly forward and skip them, and only process the next non-100 response. As
338such, these messages are neither logged nor transformed, unless explicitly
339state otherwise. Status 101 messages indicate that the protocol is changing
Daniel Corbett9f0843f2021-05-08 10:50:37 -0400340over the same connection and that HAProxy must switch to tunnel mode, just as
Willy Tarreau5843d1a2010-02-01 15:13:32 +0100341if a CONNECT had occurred. Then the Upgrade header would contain additional
342information about the type of protocol the connection is switching to.
Willy Tarreau816b9792009-09-15 21:25:21 +0200343
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200344
Davor Ocelice9ed2812017-12-25 17:49:28 +01003451.3.1. The response line
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200346------------------------
347
348Line 1 is the "response line". It is always composed of 3 fields :
349
350 - a version tag : HTTP/1.1
351 - a status code : 200
352 - a reason : OK
353
354The status code is always 3-digit. The first digit indicates a general status :
Davor Ocelice9ed2812017-12-25 17:49:28 +0100355 - 1xx = informational message to be skipped (e.g. 100, 101)
356 - 2xx = OK, content is following (e.g. 200, 206)
357 - 3xx = OK, no content following (e.g. 302, 304)
358 - 4xx = error caused by the client (e.g. 401, 403, 404)
359 - 5xx = error caused by the server (e.g. 500, 502, 503)
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200360
Lukas Tribus23953682017-04-28 13:24:30 +0000361Please refer to RFC7231 for the detailed meaning of all such codes. The
Willy Tarreaud72758d2010-01-12 10:42:19 +0100362"reason" field is just a hint, but is not parsed by clients. Anything can be
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200363found there, but it's a common practice to respect the well-established
364messages. It can be composed of one or multiple words, such as "OK", "Found",
365or "Authentication Required".
366
Davor Ocelice9ed2812017-12-25 17:49:28 +0100367HAProxy may emit the following status codes by itself :
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200368
369 Code When / reason
370 200 access to stats page, and when replying to monitoring requests
371 301 when performing a redirection, depending on the configured code
372 302 when performing a redirection, depending on the configured code
373 303 when performing a redirection, depending on the configured code
Willy Tarreaub67fdc42013-03-29 19:28:11 +0100374 307 when performing a redirection, depending on the configured code
375 308 when performing a redirection, depending on the configured code
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200376 400 for an invalid or too large request
377 401 when an authentication is required to perform the action (when
378 accessing the stats page)
Christopher Faulet87f1f3d2019-07-18 14:51:20 +0200379 403 when a request is forbidden by a "http-request deny" rule
Florian Tham9205fea2020-01-08 13:35:30 +0100380 404 when the requested resource could not be found
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200381 408 when the request timeout strikes before the request is complete
Florian Tham272e29b2020-01-08 10:19:05 +0100382 410 when the requested resource is no longer available and will not
383 be available again
Daniel Corbett9f0843f2021-05-08 10:50:37 -0400384 500 when HAProxy encounters an unrecoverable internal error, such as a
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200385 memory allocation failure, which should never happen
Daniel Corbett9f0843f2021-05-08 10:50:37 -0400386 501 when HAProxy is unable to satisfy a client request because of an
Christopher Faulete095f312020-12-07 11:22:24 +0100387 unsupported feature
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200388 502 when the server returns an empty, invalid or incomplete response, or
Christopher Faulet87f1f3d2019-07-18 14:51:20 +0200389 when an "http-response deny" rule blocks the response.
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200390 503 when no server was available to handle the request, or in response to
391 monitoring requests which match the "monitor fail" condition
392 504 when the response timeout strikes before the server responds
393
394The error 4xx and 5xx codes above may be customized (see "errorloc" in section
3954.2).
396
397
3981.3.2. The response headers
399---------------------------
400
401Response headers work exactly like request headers, and as such, HAProxy uses
402the same parsing function for both. Please refer to paragraph 1.2.2 for more
403details.
404
405
4062. Configuring HAProxy
407----------------------
408
4092.1. Configuration file format
410------------------------------
Willy Tarreau6a06a402007-07-15 20:15:28 +0200411
412HAProxy's configuration process involves 3 major sources of parameters :
413
414 - the arguments from the command-line, which always take precedence
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100415 - the configuration file(s), whose format is described here
Thayne McCombscdbcca92021-01-07 21:24:41 -0700416 - the running process's environment, in case some environment variables are
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100417 explicitly referenced
Willy Tarreau6a06a402007-07-15 20:15:28 +0200418
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100419The configuration file follows a fairly simple hierarchical format which obey
420a few basic rules:
Willy Tarreau0ba27502007-12-24 16:55:16 +0100421
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100422 1. a configuration file is an ordered sequence of statements
423
424 2. a statement is a single non-empty line before any unprotected "#" (hash)
425
426 3. a line is a series of tokens or "words" delimited by unprotected spaces or
427 tab characters
428
429 4. the first word or sequence of words of a line is one of the keywords or
430 keyword sequences listed in this document
431
432 5. all other words are all arguments of the first one, some being well-known
433 keywords listed in this document, others being values, references to other
434 parts of the configuration, or expressions
435
436 6. certain keywords delimit a section inside which only a subset of keywords
437 are supported
438
439 7. a section ends at the end of a file or on a special keyword starting a new
440 section
441
442This is all that is needed to know to write a simple but reliable configuration
443generator, but this is not enough to reliably parse any configuration nor to
444figure how to deal with certain corner cases.
445
446First, there are a few consequences of the rules above. Rule 6 and 7 imply that
447the keywords used to define a new section are valid everywhere and cannot have
448a different meaning in a specific section. These keywords are always a single
449word (as opposed to a sequence of words), and traditionally the section that
450follows them is designated using the same name. For example when speaking about
451the "global section", it designates the section of configuration that follows
452the "global" keyword. This usage is used a lot in error messages to help locate
453the parts that need to be addressed.
454
455A number of sections create an internal object or configuration space, which
456requires to be distinguished from other ones. In this case they will take an
457extra word which will set the name of this particular section. For some of them
458the section name is mandatory. For example "frontend foo" will create a new
459section of type "frontend" named "foo". Usually a name is specific to its
460section and two sections of different types may use the same name, but this is
461not recommended as it tends to complexify configuration management.
462
463A direct consequence of rule 7 is that when multiple files are read at once,
464each of them must start with a new section, and the end of each file will end
465a section. A file cannot contain sub-sections nor end an existing section and
466start a new one.
467
468Rule 1 mentioned that ordering matters. Indeed, some keywords create directives
469that can be repeated multiple times to create ordered sequences of rules to be
470applied in a certain order. For example "tcp-request" can be used to alternate
471"accept" and "reject" rules on varying criteria. As such, a configuration file
472processor must always preserve a section's ordering when editing a file. The
473ordering of sections usually does not matter except for the global section
474which must be placed before other sections, but it may be repeated if needed.
475In addition, some automatic identifiers may automatically be assigned to some
476of the created objects (e.g. proxies), and by reordering sections, their
477identifiers will change. These ones appear in the statistics for example. As
478such, the configuration below will assign "foo" ID number 1 and "bar" ID number
4792, which will be swapped if the two sections are reversed:
480
481 listen foo
482 bind :80
483
484 listen bar
485 bind :81
486
487Another important point is that according to rules 2 and 3 above, empty lines,
488spaces, tabs, and comments following and unprotected "#" character are not part
489of the configuration as they are just used as delimiters. This implies that the
490following configurations are strictly equivalent:
491
492 global#this is the global section
493 daemon#daemonize
494 frontend foo
495 mode http # or tcp
496
497and:
498
499 global
500 daemon
501
502 # this is the public web frontend
503 frontend foo
504 mode http
505
506The common practice is to align to the left only the keyword that initiates a
507new section, and indent (i.e. prepend a tab character or a few spaces) all
508other keywords so that it's instantly visible that they belong to the same
509section (as done in the second example above). Placing comments before a new
510section helps the reader decide if it's the desired one. Leaving a blank line
511at the end of a section also visually helps spotting the end when editing it.
512
513Tabs are very convenient for indent but they do not copy-paste well. If spaces
514are used instead, it is recommended to avoid placing too many (2 to 4) so that
515editing in field doesn't become a burden with limited editors that do not
516support automatic indent.
517
518In the early days it used to be common to see arguments split at fixed tab
519positions because most keywords would not take more than two arguments. With
520modern versions featuring complex expressions this practice does not stand
521anymore, and is not recommended.
522
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200523
William Lallemandf9873ba2015-05-05 17:37:14 +02005242.2. Quoting and escaping
525-------------------------
526
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100527In modern configurations, some arguments require the use of some characters
528that were previously considered as pure delimiters. In order to make this
529possible, HAProxy supports character escaping by prepending a backslash ('\')
530in front of the character to be escaped, weak quoting within double quotes
531('"') and strong quoting within single quotes ("'").
William Lallemandf9873ba2015-05-05 17:37:14 +0200532
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100533This is pretty similar to what is done in a number of programming languages and
534very close to what is commonly encountered in Bourne shell. The principle is
535the following: while the configuration parser cuts the lines into words, it
536also takes care of quotes and backslashes to decide whether a character is a
537delimiter or is the raw representation of this character within the current
538word. The escape character is then removed, the quotes are removed, and the
539remaining word is used as-is as a keyword or argument for example.
William Lallemandf9873ba2015-05-05 17:37:14 +0200540
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100541If a backslash is needed in a word, it must either be escaped using itself
542(i.e. double backslash) or be strongly quoted.
543
544Escaping outside quotes is achieved by preceding a special character by a
545backslash ('\'):
William Lallemandf9873ba2015-05-05 17:37:14 +0200546
547 \ to mark a space and differentiate it from a delimiter
548 \# to mark a hash and differentiate it from a comment
549 \\ to use a backslash
550 \' to use a single quote and differentiate it from strong quoting
551 \" to use a double quote and differentiate it from weak quoting
552
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100553In addition, a few non-printable characters may be emitted using their usual
554C-language representation:
555
556 \n to insert a line feed (LF, character \x0a or ASCII 10 decimal)
557 \r to insert a carriage return (CR, character \x0d or ASCII 13 decimal)
558 \t to insert a tab (character \x09 or ASCII 9 decimal)
559 \xNN to insert character having ASCII code hex NN (e.g \x0a for LF).
560
561Weak quoting is achieved by surrounding double quotes ("") around the character
562or sequence of characters to protect. Weak quoting prevents the interpretation
563of:
William Lallemandf9873ba2015-05-05 17:37:14 +0200564
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100565 space or tab as a word separator
William Lallemandf9873ba2015-05-05 17:37:14 +0200566 ' single quote as a strong quoting delimiter
567 # hash as a comment start
568
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100569Weak quoting permits the interpretation of environment variables (which are not
570evaluated outside of quotes) by preceding them with a dollar sign ('$'). If a
571dollar character is needed inside double quotes, it must be escaped using a
572backslash.
William Lallemandb2f07452015-05-12 14:27:13 +0200573
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100574Strong quoting is achieved by surrounding single quotes ('') around the
575character or sequence of characters to protect. Inside single quotes, nothing
576is interpreted, it's the efficient way to quote regular expressions.
William Lallemandf9873ba2015-05-05 17:37:14 +0200577
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100578As a result, here is the matrix indicating how special characters can be
579entered in different contexts (unprintable characters are replaced with their
580name within angle brackets). Note that some characters that may only be
581represented escaped have no possible representation inside single quotes,
582hence the '-' there:
William Lallemandf9873ba2015-05-05 17:37:14 +0200583
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100584 Character | Unquoted | Weakly quoted | Strongly quoted
585 -----------+---------------+-----------------------------+-----------------
586 <TAB> | \<TAB>, \x09 | "<TAB>", "\<TAB>", "\x09" | '<TAB>'
587 <LF> | \n, \x0a | "\n", "\x0a" | -
588 <CR> | \r, \x0d | "\r", "\x0d" | -
589 <SPC> | \<SPC>, \x20 | "<SPC>", "\<SPC>", "\x20" | '<SPC>'
590 " | \", \x22 | "\"", "\x22" | '"'
591 # | \#, \x23 | "#", "\#", "\x23" | '#'
592 $ | $, \$, \x24 | "\$", "\x24" | '$'
593 ' | \', \x27 | "'", "\'", "\x27" | -
594 \ | \\, \x5c | "\\", "\x5c" | '\'
William Lallemandf9873ba2015-05-05 17:37:14 +0200595
596 Example:
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100597 # those are all strictly equivalent:
William Lallemandf9873ba2015-05-05 17:37:14 +0200598 log-format %{+Q}o\ %t\ %s\ %{-Q}r
599 log-format "%{+Q}o %t %s %{-Q}r"
600 log-format '%{+Q}o %t %s %{-Q}r'
601 log-format "%{+Q}o %t"' %s %{-Q}r'
602 log-format "%{+Q}o %t"' %s'\ %{-Q}r
603
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100604There is one particular case where a second level of quoting or escaping may be
605necessary. Some keywords take arguments within parenthesis, sometimes delimited
606by commas. These arguments are commonly integers or predefined words, but when
607they are arbitrary strings, it may be required to perform a separate level of
608escaping to disambiguate the characters that belong to the argument from the
609characters that are used to delimit the arguments themselves. A pretty common
610case is the "regsub" converter. It takes a regular expression in argument, and
611if a closing parenthesis is needed inside, this one will require to have its
612own quotes.
613
614The keyword argument parser is exactly the same as the top-level one regarding
615quotes, except that is will not make special cases of backslashes. But what is
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +0500616not always obvious is that the delimiters used inside must first be escaped or
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100617quoted so that they are not resolved at the top level.
618
619Let's take this example making use of the "regsub" converter which takes 3
620arguments, one regular expression, one replacement string and one set of flags:
621
622 # replace all occurrences of "foo" with "blah" in the path:
623 http-request set-path %[path,regsub(foo,blah,g)]
624
625Here no special quoting was necessary. But if now we want to replace either
626"foo" or "bar" with "blah", we'll need the regular expression "(foo|bar)". We
627cannot write:
628
629 http-request set-path %[path,regsub((foo|bar),blah,g)]
630
631because we would like the string to cut like this:
632
633 http-request set-path %[path,regsub((foo|bar),blah,g)]
634 |---------|----|-|
635 arg1 _/ / /
636 arg2 __________/ /
637 arg3 ______________/
638
639but actually what is passed is a string between the opening and closing
640parenthesis then garbage:
641
642 http-request set-path %[path,regsub((foo|bar),blah,g)]
643 |--------|--------|
644 arg1=(foo|bar _/ /
645 trailing garbage _________/
646
647The obvious solution here seems to be that the closing parenthesis needs to be
648quoted, but alone this will not work, because as mentioned above, quotes are
649processed by the top-level parser which will resolve them before processing
650this word:
651
652 http-request set-path %[path,regsub("(foo|bar)",blah,g)]
653 ------------ -------- ----------------------------------
654 word1 word2 word3=%[path,regsub((foo|bar),blah,g)]
655
656So we didn't change anything for the argument parser at the second level which
657still sees a truncated regular expression as the only argument, and garbage at
658the end of the string. By escaping the quotes they will be passed unmodified to
659the second level:
660
661 http-request set-path %[path,regsub(\"(foo|bar)\",blah,g)]
662 ------------ -------- ------------------------------------
663 word1 word2 word3=%[path,regsub("(foo|bar)",blah,g)]
664 |---------||----|-|
665 arg1=(foo|bar) _/ / /
666 arg2=blah ___________/ /
667 arg3=g _______________/
668
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +0500669Another approach consists in using single quotes outside the whole string and
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100670double quotes inside (so that the double quotes are not stripped again):
671
672 http-request set-path '%[path,regsub("(foo|bar)",blah,g)]'
673 ------------ -------- ----------------------------------
674 word1 word2 word3=%[path,regsub("(foo|bar)",blah,g)]
675 |---------||----|-|
676 arg1=(foo|bar) _/ / /
677 arg2 ___________/ /
678 arg3 _______________/
679
680When using regular expressions, it can happen that the dollar ('$') character
681appears in the expression or that a backslash ('\') is used in the replacement
682string. In this case these ones will also be processed inside the double quotes
683thus single quotes are preferred (or double escaping). Example:
684
685 http-request set-path '%[path,regsub("^/(here)(/|$)","my/\1",g)]'
686 ------------ -------- -----------------------------------------
687 word1 word2 word3=%[path,regsub("^/(here)(/|$)","my/\1",g)]
688 |-------------| |-----||-|
689 arg1=(here)(/|$) _/ / /
690 arg2=my/\1 ________________/ /
691 arg3 ______________________/
692
Daniel Corbett9f0843f2021-05-08 10:50:37 -0400693Remember that backslashes are not escape characters within single quotes and
Willy Tarreau6f1129d2020-11-25 19:58:20 +0100694that the whole word3 above is already protected against them using the single
695quotes. Conversely, if double quotes had been used around the whole expression,
696single the dollar character and the backslashes would have been resolved at top
697level, breaking the argument contents at the second level.
698
699When in doubt, simply do not use quotes anywhere, and start to place single or
700double quotes around arguments that require a comma or a closing parenthesis,
701and think about escaping these quotes using a backslash of the string contains
702a dollar or a backslash. Again, this is pretty similar to what is used under
703a Bourne shell when double-escaping a command passed to "eval". For API writers
704the best is probably to place escaped quotes around each and every argument,
705regardless of their contents. Users will probably find that using single quotes
706around the whole expression and double quotes around each argument provides
707more readable configurations.
William Lallemandf9873ba2015-05-05 17:37:14 +0200708
709
William Lallemandb2f07452015-05-12 14:27:13 +02007102.3. Environment variables
711--------------------------
712
713HAProxy's configuration supports environment variables. Those variables are
714interpreted only within double quotes. Variables are expanded during the
715configuration parsing. Variable names must be preceded by a dollar ("$") and
716optionally enclosed with braces ("{}") similarly to what is done in Bourne
717shell. Variable names can contain alphanumerical characters or the character
Amaury Denoyellefa41cb62020-10-01 14:32:35 +0200718underscore ("_") but should not start with a digit. If the variable contains a
719list of several values separated by spaces, it can be expanded as individual
720arguments by enclosing the variable with braces and appending the suffix '[*]'
721before the closing brace.
William Lallemandb2f07452015-05-12 14:27:13 +0200722
723 Example:
724
725 bind "fd@${FD_APP1}"
726
727 log "${LOCAL_SYSLOG}:514" local0 notice # send to local server
728
729 user "$HAPROXY_USER"
730
William Lallemand4d03e432019-06-14 15:35:37 +0200731Some variables are defined by HAProxy, they can be used in the configuration
732file, or could be inherited by a program (See 3.7. Programs):
William Lallemanddaf4cd22018-04-17 16:46:13 +0200733
William Lallemand4d03e432019-06-14 15:35:37 +0200734* HAPROXY_LOCALPEER: defined at the startup of the process which contains the
735 name of the local peer. (See "-L" in the management guide.)
736
737* HAPROXY_CFGFILES: list of the configuration files loaded by HAProxy,
738 separated by semicolons. Can be useful in the case you specified a
739 directory.
740
741* HAPROXY_MWORKER: In master-worker mode, this variable is set to 1.
742
John Roeslerfb2fce12019-07-10 15:45:51 -0500743* HAPROXY_CLI: configured listeners addresses of the stats socket for every
William Lallemand4d03e432019-06-14 15:35:37 +0200744 processes, separated by semicolons.
745
John Roeslerfb2fce12019-07-10 15:45:51 -0500746* HAPROXY_MASTER_CLI: In master-worker mode, listeners addresses of the master
William Lallemand4d03e432019-06-14 15:35:37 +0200747 CLI, separated by semicolons.
748
Willy Tarreaua46f1af2021-05-06 10:25:11 +0200749In addition, some pseudo-variables are internally resolved and may be used as
750regular variables. Pseudo-variables always start with a dot ('.'), and are the
751only ones where the dot is permitted. The current list of pseudo-variables is:
752
753* .FILE: the name of the configuration file currently being parsed.
754
755* .LINE: the line number of the configuration file currently being parsed,
756 starting at one.
757
758* .SECTION: the name of the section currently being parsed, or its type if the
759 section doesn't have a name (e.g. "global"), or an empty string before the
760 first section.
761
762These variables are resolved at the location where they are parsed. For example
763if a ".LINE" variable is used in a "log-format" directive located in a defaults
764section, its line number will be resolved before parsing and compiling the
765"log-format" directive, so this same line number will be reused by subsequent
766proxies.
767
768This way it is possible to emit information to help locate a rule in variables,
769logs, error statuses, health checks, header values, or even to use line numbers
770to name some config objects like servers for example.
771
William Lallemand4d03e432019-06-14 15:35:37 +0200772See also "external-check command" for other variables.
William Lallemandb2f07452015-05-12 14:27:13 +0200773
Willy Tarreau4b103022021-02-12 17:59:10 +0100774
7752.4. Conditional blocks
776-----------------------
777
778It may sometimes be convenient to be able to conditionally enable or disable
779some arbitrary parts of the configuration, for example to enable/disable SSL or
780ciphers, enable or disable some pre-production listeners without modifying the
781configuration, or adjust the configuration's syntax to support two distinct
782versions of HAProxy during a migration.. HAProxy brings a set of nestable
783preprocessor-like directives which allow to integrate or ignore some blocks of
784text. These directives must be placed on their own line and they act on the
785lines that follow them. Two of them support an expression, the other ones only
786switch to an alternate block or end a current level. The 4 following directives
787are defined to form conditional blocks:
788
789 - .if <condition>
790 - .elif <condition>
791 - .else
792 - .endif
793
794The ".if" directive nests a new level, ".elif" stays at the same level, ".else"
795as well, and ".endif" closes a level. Each ".if" must be terminated by a
796matching ".endif". The ".elif" may only be placed after ".if" or ".elif", and
797there is no limit to the number of ".elif" that may be chained. There may be
798only one ".else" per ".if" and it must always be after the ".if" or the last
799".elif" of a block.
800
801Comments may be placed on the same line if needed after a '#', they will be
802ignored. The directives are tokenized like other configuration directives, and
803as such it is possible to use environment variables in conditions.
804
805The conditions are currently limited to:
806
807 - an empty string, always returns "false"
808 - the integer zero ('0'), always returns "false"
809 - a non-nul integer (e.g. '1'), always returns "true".
Willy Tarreau42ed14b2021-05-06 15:55:14 +0200810 - a predicate optionally followed by argument(s) in parenthesis.
811
812The list of currently supported predicates is the following:
813
814 - defined(<name>) : returns true if an environment variable <name>
815 exists, regardless of its contents
816
Willy Tarreau58ca7062021-05-06 16:34:23 +0200817 - feature(<name>) : returns true if feature <name> is listed as present
818 in the features list reported by "haproxy -vv"
819 (which means a <name> appears after a '+')
820
Willy Tarreau6492e872021-05-06 16:10:09 +0200821 - streq(<str1>,<str2>) : returns true only if the two strings are equal
822 - strneq(<str1>,<str2>) : returns true only if the two strings differ
823
Willy Tarreau0b7c78a2021-05-06 16:53:26 +0200824 - version_atleast(<ver>): returns true if the current haproxy version is
825 at least as recent as <ver> otherwise false. The
826 version syntax is the same as shown by "haproxy -v"
827 and missing components are assumed as being zero.
828
829 - version_before(<ver>) : returns true if the current haproxy version is
830 strictly older than <ver> otherwise false. The
831 version syntax is the same as shown by "haproxy -v"
832 and missing components are assumed as being zero.
833
Willy Tarreau42ed14b2021-05-06 15:55:14 +0200834Example:
Willy Tarreau4b103022021-02-12 17:59:10 +0100835
Willy Tarreau42ed14b2021-05-06 15:55:14 +0200836 .if defined(HAPROXY_MWORKER)
837 listen mwcli_px
838 bind :1111
839 ...
840 .endif
Willy Tarreau4b103022021-02-12 17:59:10 +0100841
Willy Tarreau6492e872021-05-06 16:10:09 +0200842 .if strneq("$SSL_ONLY",yes)
843 bind :80
844 .endif
845
846 .if streq("$WITH_SSL",yes)
Willy Tarreau58ca7062021-05-06 16:34:23 +0200847 .if feature(OPENSSL)
Willy Tarreau6492e872021-05-06 16:10:09 +0200848 bind :443 ssl crt ...
Willy Tarreau58ca7062021-05-06 16:34:23 +0200849 .endif
Willy Tarreau6492e872021-05-06 16:10:09 +0200850 .endif
851
Willy Tarreau0b7c78a2021-05-06 16:53:26 +0200852 .if version_atleast(2.4-dev19)
853 profiling.memory on
854 .endif
855
Willy Tarreau7190b982021-05-07 08:59:50 +0200856Four other directives are provided to report some status:
Willy Tarreau4b103022021-02-12 17:59:10 +0100857
Willy Tarreau7190b982021-05-07 08:59:50 +0200858 - .diag "message" : emit this message only when in diagnostic mode (-dD)
Willy Tarreau4b103022021-02-12 17:59:10 +0100859 - .notice "message" : emit this message at level NOTICE
860 - .warning "message" : emit this message at level WARNING
861 - .alert "message" : emit this message at level ALERT
862
863Messages emitted at level WARNING may cause the process to fail to start if the
864"strict-mode" is enabled. Messages emitted at level ALERT will always cause a
865fatal error. These can be used to detect some inappropriate conditions and
866provide advice to the user.
867
868Example:
869
870 .if "${A}"
871 .if "${B}"
872 .notice "A=1, B=1"
873 .elif "${C}"
874 .notice "A=1, B=0, C=1"
875 .elif "${D}"
876 .warning "A=1, B=0, C=0, D=1"
877 .else
878 .alert "A=1, B=0, C=0, D=0"
879 .endif
880 .else
881 .notice "A=0"
882 .endif
883
Willy Tarreau7190b982021-05-07 08:59:50 +0200884 .diag "WTA/2021-05-07: replace 'redirect' with 'return' after switch to 2.4"
885 http-request redirect location /goaway if ABUSE
886
Willy Tarreau4b103022021-02-12 17:59:10 +0100887
8882.5. Time format
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200889----------------
890
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +0100891Some parameters involve values representing time, such as timeouts. These
Willy Tarreau0ba27502007-12-24 16:55:16 +0100892values are generally expressed in milliseconds (unless explicitly stated
893otherwise) but may be expressed in any other unit by suffixing the unit to the
894numeric value. It is important to consider this because it will not be repeated
895for every keyword. Supported units are :
896
897 - us : microseconds. 1 microsecond = 1/1000000 second
898 - ms : milliseconds. 1 millisecond = 1/1000 second. This is the default.
899 - s : seconds. 1s = 1000ms
900 - m : minutes. 1m = 60s = 60000ms
901 - h : hours. 1h = 60m = 3600s = 3600000ms
902 - d : days. 1d = 24h = 1440m = 86400s = 86400000ms
903
904
Willy Tarreau4b103022021-02-12 17:59:10 +01009052.6. Examples
Patrick Mezard35da19c2010-06-12 17:02:47 +0200906-------------
907
908 # Simple configuration for an HTTP proxy listening on port 80 on all
909 # interfaces and forwarding requests to a single backend "servers" with a
910 # single server "server1" listening on 127.0.0.1:8000
911 global
912 daemon
913 maxconn 256
914
915 defaults
916 mode http
917 timeout connect 5000ms
918 timeout client 50000ms
919 timeout server 50000ms
920
921 frontend http-in
922 bind *:80
923 default_backend servers
924
925 backend servers
926 server server1 127.0.0.1:8000 maxconn 32
927
928
929 # The same configuration defined with a single listen block. Shorter but
930 # less expressive, especially in HTTP mode.
931 global
932 daemon
933 maxconn 256
934
935 defaults
936 mode http
937 timeout connect 5000ms
938 timeout client 50000ms
939 timeout server 50000ms
940
941 listen http-in
942 bind *:80
943 server server1 127.0.0.1:8000 maxconn 32
944
945
946Assuming haproxy is in $PATH, test these configurations in a shell with:
947
Willy Tarreauccb289d2010-12-11 20:19:38 +0100948 $ sudo haproxy -f configuration.conf -c
Patrick Mezard35da19c2010-06-12 17:02:47 +0200949
950
Willy Tarreauc57f0e22009-05-10 13:12:33 +02009513. Global parameters
Willy Tarreau6a06a402007-07-15 20:15:28 +0200952--------------------
953
954Parameters in the "global" section are process-wide and often OS-specific. They
955are generally set once for all and do not need being changed once correct. Some
956of them have command-line equivalents.
957
958The following keywords are supported in the "global" section :
959
960 * Process management and security
Emeric Brunc8e8d122012-10-02 18:42:10 +0200961 - ca-base
Willy Tarreau6a06a402007-07-15 20:15:28 +0200962 - chroot
Emeric Brunc8e8d122012-10-02 18:42:10 +0200963 - crt-base
Baptiste Assmann3493d0f2015-10-12 20:21:23 +0200964 - cpu-map
Willy Tarreau6a06a402007-07-15 20:15:28 +0200965 - daemon
Willy Tarreau8a022d52021-04-27 20:29:11 +0200966 - default-path
Baptiste Assmann3493d0f2015-10-12 20:21:23 +0200967 - description
968 - deviceatlas-json-file
969 - deviceatlas-log-level
970 - deviceatlas-separator
971 - deviceatlas-properties-cookie
Amaury Denoyelled2e53cd2021-05-06 16:21:39 +0200972 - expose-experimental-directives
Simon Horman98637e52014-06-20 12:30:16 +0900973 - external-check
Willy Tarreau6a06a402007-07-15 20:15:28 +0200974 - gid
975 - group
Cyril Bonté203ec5a2017-03-23 22:44:13 +0100976 - hard-stop-after
Christopher Faulet98fbe952019-07-22 16:18:24 +0200977 - h1-case-adjust
978 - h1-case-adjust-file
Willy Tarreaud96f1122019-12-03 07:07:36 +0100979 - insecure-fork-wanted
Willy Tarreaua45a8b52019-12-06 16:31:45 +0100980 - insecure-setuid-wanted
Emmanuel Hocdet70df7bf2019-01-04 11:08:20 +0100981 - issuers-chain-path
Amaury Denoyelle0ea2c4f2021-07-09 17:14:30 +0200982 - h2-workaround-bogus-websocket-clients
Dragan Dosen13cd54c2020-06-18 18:24:05 +0200983 - localpeer
Willy Tarreau6a06a402007-07-15 20:15:28 +0200984 - log
Baptiste Assmann3493d0f2015-10-12 20:21:23 +0200985 - log-tag
Joe Williamsdf5b38f2010-12-29 17:05:48 +0100986 - log-send-hostname
Baptiste Assmann3493d0f2015-10-12 20:21:23 +0200987 - lua-load
Thierry Fournier59f11be2020-11-29 00:37:41 +0100988 - lua-load-per-thread
Tim Duesterhusdd74b5f2020-01-12 13:55:40 +0100989 - lua-prepend-path
William Lallemand27edc4b2019-05-07 17:49:33 +0200990 - mworker-max-reloads
Willy Tarreau6a06a402007-07-15 20:15:28 +0200991 - nbproc
Christopher Fauletbe0faa22017-08-29 15:37:10 +0200992 - nbthread
Baptiste Assmann3493d0f2015-10-12 20:21:23 +0200993 - node
Amaury Denoyelle0f50cb92021-03-26 18:50:33 +0100994 - numa-cpu-mapping
Willy Tarreau6a06a402007-07-15 20:15:28 +0200995 - pidfile
Willy Tarreau119e50e2020-05-22 13:53:29 +0200996 - pp2-never-send-local
Willy Tarreau1d549722016-02-16 12:41:57 +0100997 - presetenv
998 - resetenv
Willy Tarreau6a06a402007-07-15 20:15:28 +0200999 - uid
1000 - ulimit-n
1001 - user
Willy Tarreau636848a2019-04-15 19:38:50 +02001002 - set-dumpable
Willy Tarreau13d2ba22021-03-26 11:38:08 +01001003 - set-var
Willy Tarreau1d549722016-02-16 12:41:57 +01001004 - setenv
Willy Tarreaufbee7132007-10-18 13:53:22 +02001005 - stats
Baptiste Assmann3493d0f2015-10-12 20:21:23 +02001006 - ssl-default-bind-ciphers
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001007 - ssl-default-bind-ciphersuites
Jerome Magninb203ff62020-04-03 15:28:22 +02001008 - ssl-default-bind-curves
Baptiste Assmann3493d0f2015-10-12 20:21:23 +02001009 - ssl-default-bind-options
1010 - ssl-default-server-ciphers
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001011 - ssl-default-server-ciphersuites
Baptiste Assmann3493d0f2015-10-12 20:21:23 +02001012 - ssl-default-server-options
1013 - ssl-dh-param-file
Emeric Brun850efd52014-01-29 12:24:34 +01001014 - ssl-server-verify
Emmanuel Hocdetc3b7e742020-04-22 11:06:19 +02001015 - ssl-skip-self-issued-ca
Willy Tarreauceb24bc2010-11-09 12:46:41 +01001016 - unix-bind
Willy Tarreau1d549722016-02-16 12:41:57 +01001017 - unsetenv
Thomas Holmesdb04f192015-05-18 13:21:39 +01001018 - 51degrees-data-file
1019 - 51degrees-property-name-list
Dragan Dosen93b38d92015-06-29 16:43:25 +02001020 - 51degrees-property-separator
Dragan Dosenae6d39a2015-06-29 16:43:27 +02001021 - 51degrees-cache-size
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02001022 - wurfl-data-file
1023 - wurfl-information-list
1024 - wurfl-information-list-separator
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02001025 - wurfl-cache-size
William Dauchy0fec3ab2019-10-27 20:08:11 +01001026 - strict-limits
Willy Tarreaud72758d2010-01-12 10:42:19 +01001027
Willy Tarreau6a06a402007-07-15 20:15:28 +02001028 * Performance tuning
William Dauchy0a8824f2019-10-27 20:08:09 +01001029 - busy-polling
Willy Tarreau1746eec2014-04-25 10:46:47 +02001030 - max-spread-checks
Willy Tarreau6a06a402007-07-15 20:15:28 +02001031 - maxconn
Willy Tarreau81c25d02011-09-07 15:17:21 +02001032 - maxconnrate
William Lallemandd85f9172012-11-09 17:05:39 +01001033 - maxcomprate
William Lallemand072a2bf2012-11-20 17:01:01 +01001034 - maxcompcpuusage
Willy Tarreauff4f82d2009-02-06 11:28:13 +01001035 - maxpipes
Willy Tarreau93e7c002013-10-07 18:51:07 +02001036 - maxsessrate
Willy Tarreau403edff2012-09-06 11:58:37 +02001037 - maxsslconn
Willy Tarreaue43d5322013-10-07 20:01:52 +02001038 - maxsslrate
Baptiste Assmann3493d0f2015-10-12 20:21:23 +02001039 - maxzlibmem
Willy Tarreau6a06a402007-07-15 20:15:28 +02001040 - noepoll
1041 - nokqueue
Emmanuel Hocdet0ba4f482019-04-08 16:53:32 +00001042 - noevports
Willy Tarreau6a06a402007-07-15 20:15:28 +02001043 - nopoll
Willy Tarreauff4f82d2009-02-06 11:28:13 +01001044 - nosplice
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03001045 - nogetaddrinfo
Lukas Tribusa0bcbdc2016-09-12 21:42:20 +00001046 - noreuseport
Willy Tarreau75c62c22018-11-22 11:02:09 +01001047 - profiling.tasks
Willy Tarreaufe255b72007-10-14 23:09:26 +02001048 - spread-checks
Baptiste Assmann5626f482015-08-23 10:00:10 +02001049 - server-state-base
Baptiste Assmannef1f0fc2015-08-23 10:06:39 +02001050 - server-state-file
Grant Zhang872f9c22017-01-21 01:10:18 +00001051 - ssl-engine
Grant Zhangfa6c7ee2017-01-14 01:42:15 +00001052 - ssl-mode-async
Baptiste Assmann3493d0f2015-10-12 20:21:23 +02001053 - tune.buffers.limit
1054 - tune.buffers.reserve
Willy Tarreau27a674e2009-08-17 07:23:33 +02001055 - tune.bufsize
Willy Tarreau43961d52010-10-04 20:39:20 +02001056 - tune.chksize
William Lallemandf3747832012-11-09 12:33:10 +01001057 - tune.comp.maxlevel
Willy Tarreaubc52bec2020-06-18 08:58:47 +02001058 - tune.fd.edge-triggered
Willy Tarreaufe20e5b2017-07-27 11:42:14 +02001059 - tune.h2.header-table-size
Willy Tarreaue6baec02017-07-27 11:45:11 +02001060 - tune.h2.initial-window-size
Willy Tarreau5242ef82017-07-27 11:47:28 +02001061 - tune.h2.max-concurrent-streams
Willy Tarreau193b8c62012-11-22 00:17:38 +01001062 - tune.http.cookielen
Stéphane Cottin23e9e932017-05-18 08:58:41 +02001063 - tune.http.logurilen
Willy Tarreauac1932d2011-10-24 19:14:41 +02001064 - tune.http.maxhdr
Willy Tarreau76cc6992020-07-01 18:49:24 +02001065 - tune.idle-pool.shared
Willy Tarreau7e312732014-02-12 16:35:14 +01001066 - tune.idletimer
Thierry FOURNIER90da1912015-03-05 11:17:06 +01001067 - tune.lua.forced-yield
Willy Tarreau32f61e22015-03-18 17:54:59 +01001068 - tune.lua.maxmem
Thierry FOURNIER90da1912015-03-05 11:17:06 +01001069 - tune.lua.session-timeout
1070 - tune.lua.task-timeout
Thierry FOURNIER7dd784b2015-10-01 14:49:33 +02001071 - tune.lua.service-timeout
Willy Tarreaua0250ba2008-01-06 11:22:57 +01001072 - tune.maxaccept
1073 - tune.maxpollevents
Willy Tarreau27a674e2009-08-17 07:23:33 +02001074 - tune.maxrewrite
Willy Tarreauf3045d22015-04-29 16:24:50 +02001075 - tune.pattern.cache-size
Willy Tarreaubd9a0a72011-10-23 21:14:29 +02001076 - tune.pipesize
Willy Tarreaua8e2d972020-07-01 18:27:16 +02001077 - tune.pool-high-fd-ratio
1078 - tune.pool-low-fd-ratio
Willy Tarreaue803de22010-01-21 17:43:04 +01001079 - tune.rcvbuf.client
1080 - tune.rcvbuf.server
Willy Tarreaub22fc302015-12-14 12:04:35 +01001081 - tune.recv_enough
Olivier Houchard1599b802018-05-24 18:59:04 +02001082 - tune.runqueue-depth
Willy Tarreaue7723bd2020-06-24 11:11:02 +02001083 - tune.sched.low-latency
Willy Tarreaue803de22010-01-21 17:43:04 +01001084 - tune.sndbuf.client
1085 - tune.sndbuf.server
Willy Tarreau6ec58db2012-11-16 16:32:15 +01001086 - tune.ssl.cachesize
William Lallemand7d42ef52020-07-06 11:41:30 +02001087 - tune.ssl.keylog
Willy Tarreaubfd59462013-02-21 07:46:09 +01001088 - tune.ssl.lifetime
Emeric Brun8dc60392014-05-09 13:52:00 +02001089 - tune.ssl.force-private-cache
Willy Tarreaubfd59462013-02-21 07:46:09 +01001090 - tune.ssl.maxrecord
Remi Gacognef46cd6e2014-06-12 14:58:40 +02001091 - tune.ssl.default-dh-param
Christopher Faulet31af49d2015-06-09 17:29:50 +02001092 - tune.ssl.ssl-ctx-cache-size
Thierry FOURNIER5bf77322017-02-25 12:45:22 +01001093 - tune.ssl.capture-cipherlist-size
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02001094 - tune.vars.global-max-size
Christopher Fauletff2613e2016-11-09 11:36:17 +01001095 - tune.vars.proc-max-size
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02001096 - tune.vars.reqres-max-size
1097 - tune.vars.sess-max-size
1098 - tune.vars.txn-max-size
William Lallemanda509e4c2012-11-07 16:54:34 +01001099 - tune.zlib.memlevel
1100 - tune.zlib.windowsize
Willy Tarreaud72758d2010-01-12 10:42:19 +01001101
Willy Tarreau6a06a402007-07-15 20:15:28 +02001102 * Debugging
Willy Tarreau6a06a402007-07-15 20:15:28 +02001103 - quiet
Willy Tarreau3eb10b82020-04-15 16:42:39 +02001104 - zero-warning
Willy Tarreau6a06a402007-07-15 20:15:28 +02001105
1106
Willy Tarreauc57f0e22009-05-10 13:12:33 +020011073.1. Process management and security
Willy Tarreau6a06a402007-07-15 20:15:28 +02001108------------------------------------
1109
Emeric Brunc8e8d122012-10-02 18:42:10 +02001110ca-base <dir>
1111 Assigns a default directory to fetch SSL CA certificates and CRLs from when a
Emmanuel Hocdet842e94e2019-12-16 16:39:17 +01001112 relative path is used with "ca-file", "ca-verify-file" or "crl-file"
1113 directives. Absolute locations specified in "ca-file", "ca-verify-file" and
1114 "crl-file" prevail and ignore "ca-base".
Emeric Brunc8e8d122012-10-02 18:42:10 +02001115
Willy Tarreau6a06a402007-07-15 20:15:28 +02001116chroot <jail dir>
1117 Changes current directory to <jail dir> and performs a chroot() there before
1118 dropping privileges. This increases the security level in case an unknown
1119 vulnerability would be exploited, since it would make it very hard for the
1120 attacker to exploit the system. This only works when the process is started
1121 with superuser privileges. It is important to ensure that <jail_dir> is both
Davor Ocelice9ed2812017-12-25 17:49:28 +01001122 empty and non-writable to anyone.
Willy Tarreaud72758d2010-01-12 10:42:19 +01001123
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001124cpu-map [auto:]<process-set>[/<thread-set>] <cpu-set>...
1125 On Linux 2.6 and above, it is possible to bind a process or a thread to a
1126 specific CPU set. This means that the process or the thread will never run on
1127 other CPUs. The "cpu-map" directive specifies CPU sets for process or thread
1128 sets. The first argument is a process set, eventually followed by a thread
1129 set. These sets have the format
1130
1131 all | odd | even | number[-[number]]
1132
1133 <number>> must be a number between 1 and 32 or 64, depending on the machine's
Davor Ocelice9ed2812017-12-25 17:49:28 +01001134 word size. Any process IDs above nbproc and any thread IDs above nbthread are
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001135 ignored. It is possible to specify a range with two such number delimited by
1136 a dash ('-'). It also is possible to specify all processes at once using
Christopher Faulet1dcb9cb2017-11-22 10:24:40 +01001137 "all", only odd numbers using "odd" or even numbers using "even", just like
1138 with the "bind-process" directive. The second and forthcoming arguments are
Amaury Denoyelle982fb532021-04-21 18:39:58 +02001139 CPU sets. Each CPU set is either a unique number starting at 0 for the first
1140 CPU or a range with two such numbers delimited by a dash ('-'). Outside of
1141 Linux and BSDs, there may be a limitation on the maximum CPU index to either
1142 31 or 63. Multiple CPU numbers or ranges may be specified, and the processes
1143 or threads will be allowed to bind to all of them. Obviously, multiple
1144 "cpu-map" directives may be specified. Each "cpu-map" directive will replace
1145 the previous ones when they overlap. A thread will be bound on the
1146 intersection of its mapping and the one of the process on which it is
1147 attached. If the intersection is null, no specific binding will be set for
1148 the thread.
Willy Tarreaufc6c0322012-11-16 16:12:27 +01001149
Christopher Fauletff4121f2017-11-22 16:38:49 +01001150 Ranges can be partially defined. The higher bound can be omitted. In such
1151 case, it is replaced by the corresponding maximum value, 32 or 64 depending
1152 on the machine's word size.
1153
Christopher Faulet26028f62017-11-22 15:01:51 +01001154 The prefix "auto:" can be added before the process set to let HAProxy
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001155 automatically bind a process or a thread to a CPU by incrementing
1156 process/thread and CPU sets. To be valid, both sets must have the same
1157 size. No matter the declaration order of the CPU sets, it will be bound from
1158 the lowest to the highest bound. Having a process and a thread range with the
1159 "auto:" prefix is not supported. Only one range is supported, the other one
1160 must be a fixed number.
Christopher Faulet26028f62017-11-22 15:01:51 +01001161
1162 Examples:
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001163 cpu-map 1-4 0-3 # bind processes 1 to 4 on the first 4 CPUs
1164
1165 cpu-map 1/all 0-3 # bind all threads of the first process on the
1166 # first 4 CPUs
1167
1168 cpu-map 1- 0- # will be replaced by "cpu-map 1-64 0-63"
1169 # or "cpu-map 1-32 0-31" depending on the machine's
1170 # word size.
1171
Christopher Faulet26028f62017-11-22 15:01:51 +01001172 # all these lines bind the process 1 to the cpu 0, the process 2 to cpu 1
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001173 # and so on.
Christopher Faulet26028f62017-11-22 15:01:51 +01001174 cpu-map auto:1-4 0-3
1175 cpu-map auto:1-4 0-1 2-3
1176 cpu-map auto:1-4 3 2 1 0
1177
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001178 # all these lines bind the thread 1 to the cpu 0, the thread 2 to cpu 1
1179 # and so on.
1180 cpu-map auto:1/1-4 0-3
1181 cpu-map auto:1/1-4 0-1 2-3
1182 cpu-map auto:1/1-4 3 2 1 0
1183
Davor Ocelice9ed2812017-12-25 17:49:28 +01001184 # bind each process to exactly one CPU using all/odd/even keyword
Christopher Faulet26028f62017-11-22 15:01:51 +01001185 cpu-map auto:all 0-63
1186 cpu-map auto:even 0-31
1187 cpu-map auto:odd 32-63
1188
1189 # invalid cpu-map because process and CPU sets have different sizes.
1190 cpu-map auto:1-4 0 # invalid
1191 cpu-map auto:1 0-3 # invalid
1192
Christopher Fauletcb6a9452017-11-22 16:50:41 +01001193 # invalid cpu-map because automatic binding is used with a process range
1194 # and a thread range.
1195 cpu-map auto:all/all 0 # invalid
1196 cpu-map auto:all/1-4 0 # invalid
1197 cpu-map auto:1-4/all 0 # invalid
1198
Emeric Brunc8e8d122012-10-02 18:42:10 +02001199crt-base <dir>
1200 Assigns a default directory to fetch SSL certificates from when a relative
William Dauchy238ea3b2020-01-11 13:09:12 +01001201 path is used with "crtfile" or "crt" directives. Absolute locations specified
1202 prevail and ignore "crt-base".
Emeric Brunc8e8d122012-10-02 18:42:10 +02001203
Willy Tarreau6a06a402007-07-15 20:15:28 +02001204daemon
1205 Makes the process fork into background. This is the recommended mode of
1206 operation. It is equivalent to the command line "-D" argument. It can be
Lukas Tribusf46bf952017-11-21 12:39:34 +01001207 disabled by the command line "-db" argument. This option is ignored in
1208 systemd mode.
Willy Tarreau6a06a402007-07-15 20:15:28 +02001209
Willy Tarreau8a022d52021-04-27 20:29:11 +02001210default-path { current | config | parent | origin <path> }
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001211 By default HAProxy loads all files designated by a relative path from the
Willy Tarreau8a022d52021-04-27 20:29:11 +02001212 location the process is started in. In some circumstances it might be
1213 desirable to force all relative paths to start from a different location
1214 just as if the process was started from such locations. This is what this
1215 directive is made for. Technically it will perform a temporary chdir() to
1216 the designated location while processing each configuration file, and will
1217 return to the original directory after processing each file. It takes an
1218 argument indicating the policy to use when loading files whose path does
1219 not start with a slash ('/'):
1220 - "current" indicates that all relative files are to be loaded from the
1221 directory the process is started in ; this is the default.
1222
1223 - "config" indicates that all relative files should be loaded from the
1224 directory containing the configuration file. More specifically, if the
1225 configuration file contains a slash ('/'), the longest part up to the
1226 last slash is used as the directory to change to, otherwise the current
1227 directory is used. This mode is convenient to bundle maps, errorfiles,
1228 certificates and Lua scripts together as relocatable packages. When
1229 multiple configuration files are loaded, the directory is updated for
1230 each of them.
1231
1232 - "parent" indicates that all relative files should be loaded from the
1233 parent of the directory containing the configuration file. More
1234 specifically, if the configuration file contains a slash ('/'), ".."
1235 is appended to the longest part up to the last slash is used as the
1236 directory to change to, otherwise the directory is "..". This mode is
1237 convenient to bundle maps, errorfiles, certificates and Lua scripts
1238 together as relocatable packages, but where each part is located in a
1239 different subdirectory (e.g. "config/", "certs/", "maps/", ...).
1240
1241 - "origin" indicates that all relative files should be loaded from the
1242 designated (mandatory) path. This may be used to ease management of
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001243 different HAProxy instances running in parallel on a system, where each
Willy Tarreau8a022d52021-04-27 20:29:11 +02001244 instance uses a different prefix but where the rest of the sections are
1245 made easily relocatable.
1246
1247 Each "default-path" directive instantly replaces any previous one and will
1248 possibly result in switching to a different directory. While this should
1249 always result in the desired behavior, it is really not a good practice to
1250 use multiple default-path directives, and if used, the policy ought to remain
1251 consistent across all configuration files.
1252
1253 Warning: some configuration elements such as maps or certificates are
1254 uniquely identified by their configured path. By using a relocatable layout,
1255 it becomes possible for several of them to end up with the same unique name,
1256 making it difficult to update them at run time, especially when multiple
1257 configuration files are loaded from different directories. It is essential to
1258 observe a strict collision-free file naming scheme before adopting relative
1259 paths. A robust approach could consist in prefixing all files names with
1260 their respective site name, or in doing so at the directory level.
1261
David Carlier8167f302015-06-01 13:50:06 +02001262deviceatlas-json-file <path>
1263 Sets the path of the DeviceAtlas JSON data file to be loaded by the API.
Davor Ocelice9ed2812017-12-25 17:49:28 +01001264 The path must be a valid JSON data file and accessible by HAProxy process.
David Carlier8167f302015-06-01 13:50:06 +02001265
1266deviceatlas-log-level <value>
Davor Ocelice9ed2812017-12-25 17:49:28 +01001267 Sets the level of information returned by the API. This directive is
David Carlier8167f302015-06-01 13:50:06 +02001268 optional and set to 0 by default if not set.
1269
1270deviceatlas-separator <char>
1271 Sets the character separator for the API properties results. This directive
1272 is optional and set to | by default if not set.
1273
Cyril Bonté0306c4a2015-10-26 22:37:38 +01001274deviceatlas-properties-cookie <name>
Cyril Bonté307ee1e2015-09-28 23:16:06 +02001275 Sets the client cookie's name used for the detection if the DeviceAtlas
1276 Client-side component was used during the request. This directive is optional
1277 and set to DAPROPS by default if not set.
David Carlier29b3ca32015-09-25 14:09:21 +01001278
Amaury Denoyelled2e53cd2021-05-06 16:21:39 +02001279expose-experimental-directives
1280 This statement must appear before using directives tagged as experimental or
1281 the config file will be rejected.
1282
Simon Horman98637e52014-06-20 12:30:16 +09001283external-check
Willy Tarreaud96f1122019-12-03 07:07:36 +01001284 Allows the use of an external agent to perform health checks. This is
1285 disabled by default as a security precaution, and even when enabled, checks
Willy Tarreaua45a8b52019-12-06 16:31:45 +01001286 may still fail unless "insecure-fork-wanted" is enabled as well. If the
1287 program launched makes use of a setuid executable (it should really not),
1288 you may also need to set "insecure-setuid-wanted" in the global section.
1289 See "option external-check", and "insecure-fork-wanted", and
1290 "insecure-setuid-wanted".
Simon Horman98637e52014-06-20 12:30:16 +09001291
Willy Tarreau6a06a402007-07-15 20:15:28 +02001292gid <number>
Thayne McCombscdbcca92021-01-07 21:24:41 -07001293 Changes the process's group ID to <number>. It is recommended that the group
Willy Tarreau6a06a402007-07-15 20:15:28 +02001294 ID is dedicated to HAProxy or to a small set of similar daemons. HAProxy must
1295 be started with a user belonging to this group, or with superuser privileges.
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001296 Note that if HAProxy is started from a user having supplementary groups, it
Michael Schererab012dd2013-01-12 18:35:19 +01001297 will only be able to drop these groups if started with superuser privileges.
Willy Tarreau6a06a402007-07-15 20:15:28 +02001298 See also "group" and "uid".
Willy Tarreaud72758d2010-01-12 10:42:19 +01001299
Willy Tarreau11770ce2019-12-03 08:29:22 +01001300group <group name>
1301 Similar to "gid" but uses the GID of group name <group name> from /etc/group.
1302 See also "gid" and "user".
1303
Cyril Bonté203ec5a2017-03-23 22:44:13 +01001304hard-stop-after <time>
1305 Defines the maximum time allowed to perform a clean soft-stop.
1306
1307 Arguments :
1308 <time> is the maximum time (by default in milliseconds) for which the
1309 instance will remain alive when a soft-stop is received via the
1310 SIGUSR1 signal.
1311
1312 This may be used to ensure that the instance will quit even if connections
1313 remain opened during a soft-stop (for example with long timeouts for a proxy
1314 in tcp mode). It applies both in TCP and HTTP mode.
1315
1316 Example:
1317 global
1318 hard-stop-after 30s
1319
Christopher Faulet98fbe952019-07-22 16:18:24 +02001320h1-case-adjust <from> <to>
1321 Defines the case adjustment to apply, when enabled, to the header name
1322 <from>, to change it to <to> before sending it to HTTP/1 clients or
1323 servers. <from> must be in lower case, and <from> and <to> must not differ
1324 except for their case. It may be repeated if several header names need to be
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05001325 adjusted. Duplicate entries are not allowed. If a lot of header names have to
Christopher Faulet98fbe952019-07-22 16:18:24 +02001326 be adjusted, it might be more convenient to use "h1-case-adjust-file".
1327 Please note that no transformation will be applied unless "option
1328 h1-case-adjust-bogus-client" or "option h1-case-adjust-bogus-server" is
1329 specified in a proxy.
1330
1331 There is no standard case for header names because, as stated in RFC7230,
1332 they are case-insensitive. So applications must handle them in a case-
1333 insensitive manner. But some bogus applications violate the standards and
1334 erroneously rely on the cases most commonly used by browsers. This problem
1335 becomes critical with HTTP/2 because all header names must be exchanged in
1336 lower case, and HAProxy follows the same convention. All header names are
1337 sent in lower case to clients and servers, regardless of the HTTP version.
1338
1339 Applications which fail to properly process requests or responses may require
1340 to temporarily use such workarounds to adjust header names sent to them for
1341 the time it takes the application to be fixed. Please note that an
1342 application which requires such workarounds might be vulnerable to content
1343 smuggling attacks and must absolutely be fixed.
1344
1345 Example:
1346 global
1347 h1-case-adjust content-length Content-Length
1348
1349 See "h1-case-adjust-file", "option h1-case-adjust-bogus-client" and
1350 "option h1-case-adjust-bogus-server".
1351
1352h1-case-adjust-file <hdrs-file>
1353 Defines a file containing a list of key/value pairs used to adjust the case
1354 of some header names before sending them to HTTP/1 clients or servers. The
1355 file <hdrs-file> must contain 2 header names per line. The first one must be
1356 in lower case and both must not differ except for their case. Lines which
1357 start with '#' are ignored, just like empty lines. Leading and trailing tabs
1358 and spaces are stripped. Duplicate entries are not allowed. Please note that
1359 no transformation will be applied unless "option h1-case-adjust-bogus-client"
1360 or "option h1-case-adjust-bogus-server" is specified in a proxy.
1361
1362 If this directive is repeated, only the last one will be processed. It is an
1363 alternative to the directive "h1-case-adjust" if a lot of header names need
1364 to be adjusted. Please read the risks associated with using this.
1365
1366 See "h1-case-adjust", "option h1-case-adjust-bogus-client" and
1367 "option h1-case-adjust-bogus-server".
1368
Willy Tarreaud96f1122019-12-03 07:07:36 +01001369insecure-fork-wanted
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001370 By default HAProxy tries hard to prevent any thread and process creation
Willy Tarreaud96f1122019-12-03 07:07:36 +01001371 after it starts. Doing so is particularly important when using Lua files of
1372 uncertain origin, and when experimenting with development versions which may
1373 still contain bugs whose exploitability is uncertain. And generally speaking
1374 it's good hygiene to make sure that no unexpected background activity can be
1375 triggered by traffic. But this prevents external checks from working, and may
1376 break some very specific Lua scripts which actively rely on the ability to
1377 fork. This option is there to disable this protection. Note that it is a bad
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001378 idea to disable it, as a vulnerability in a library or within HAProxy itself
Willy Tarreaud96f1122019-12-03 07:07:36 +01001379 will be easier to exploit once disabled. In addition, forking from Lua or
1380 anywhere else is not reliable as the forked process may randomly embed a lock
1381 set by another thread and never manage to finish an operation. As such it is
1382 highly recommended that this option is never used and that any workload
1383 requiring such a fork be reconsidered and moved to a safer solution (such as
1384 agents instead of external checks). This option supports the "no" prefix to
1385 disable it.
1386
Willy Tarreaua45a8b52019-12-06 16:31:45 +01001387insecure-setuid-wanted
1388 HAProxy doesn't need to call executables at run time (except when using
1389 external checks which are strongly recommended against), and is even expected
1390 to isolate itself into an empty chroot. As such, there basically is no valid
1391 reason to allow a setuid executable to be called without the user being fully
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001392 aware of the risks. In a situation where HAProxy would need to call external
Willy Tarreaua45a8b52019-12-06 16:31:45 +01001393 checks and/or disable chroot, exploiting a vulnerability in a library or in
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001394 HAProxy itself could lead to the execution of an external program. On Linux
Willy Tarreaua45a8b52019-12-06 16:31:45 +01001395 it is possible to lock the process so that any setuid bit present on such an
1396 executable is ignored. This significantly reduces the risk of privilege
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001397 escalation in such a situation. This is what HAProxy does by default. In case
Willy Tarreaua45a8b52019-12-06 16:31:45 +01001398 this causes a problem to an external check (for example one which would need
1399 the "ping" command), then it is possible to disable this protection by
1400 explicitly adding this directive in the global section. If enabled, it is
1401 possible to turn it back off by prefixing it with the "no" keyword.
1402
Emmanuel Hocdet70df7bf2019-01-04 11:08:20 +01001403issuers-chain-path <dir>
1404 Assigns a directory to load certificate chain for issuer completion. All
1405 files must be in PEM format. For certificates loaded with "crt" or "crt-list",
1406 if certificate chain is not included in PEM (also commonly known as
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001407 intermediate certificate), HAProxy will complete chain if the issuer of the
Emmanuel Hocdet70df7bf2019-01-04 11:08:20 +01001408 certificate corresponds to the first certificate of the chain loaded with
1409 "issuers-chain-path".
1410 A "crt" file with PrivateKey+Certificate+IntermediateCA2+IntermediateCA1
1411 could be replaced with PrivateKey+Certificate. HAProxy will complete the
1412 chain if a file with IntermediateCA2+IntermediateCA1 is present in
1413 "issuers-chain-path" directory. All other certificates with the same issuer
1414 will share the chain in memory.
1415
Amaury Denoyelle0ea2c4f2021-07-09 17:14:30 +02001416h2-workaround-bogus-websocket-clients
1417 This disables the announcement of the support for h2 websockets to clients.
1418 This can be use to overcome clients which have issues when implementing the
1419 relatively fresh RFC8441, such as Firefox 88. To allow clients to
1420 automatically downgrade to http/1.1 for the websocket tunnel, specify h2
1421 support on the bind line using "alpn" without an explicit "proto" keyword. If
1422 this statement was previously activated, this can be disabled by prefixing
1423 the keyword with "no'.
1424
Dragan Dosen13cd54c2020-06-18 18:24:05 +02001425localpeer <name>
1426 Sets the local instance's peer name. It will be ignored if the "-L"
1427 command line argument is specified or if used after "peers" section
1428 definitions. In such cases, a warning message will be emitted during
1429 the configuration parsing.
1430
1431 This option will also set the HAPROXY_LOCALPEER environment variable.
1432 See also "-L" in the management guide and "peers" section below.
1433
Jan Wagner3e678602020-12-17 22:22:32 +01001434log <address> [len <length>] [format <format>] [sample <ranges>:<sample_size>]
Frédéric Lécailled690dfa2019-04-25 10:52:17 +02001435 <facility> [max level [min level]]
Cyril Bonté3e954872018-03-20 23:30:27 +01001436 Adds a global syslog server. Several global servers can be defined. They
Davor Ocelice9ed2812017-12-25 17:49:28 +01001437 will receive logs for starts and exits, as well as all logs from proxies
Robert Tsai81ae1952007-12-05 10:47:29 +01001438 configured with "log global".
1439
1440 <address> can be one of:
1441
Willy Tarreau2769aa02007-12-27 18:26:09 +01001442 - An IPv4 address optionally followed by a colon and a UDP port. If
Robert Tsai81ae1952007-12-05 10:47:29 +01001443 no port is specified, 514 is used by default (the standard syslog
1444 port).
1445
David du Colombier24bb5f52011-03-17 10:40:23 +01001446 - An IPv6 address followed by a colon and optionally a UDP port. If
1447 no port is specified, 514 is used by default (the standard syslog
1448 port).
1449
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01001450 - A filesystem path to a datagram UNIX domain socket, keeping in mind
Robert Tsai81ae1952007-12-05 10:47:29 +01001451 considerations for chroot (be sure the path is accessible inside
1452 the chroot) and uid/gid (be sure the path is appropriately
Davor Ocelice9ed2812017-12-25 17:49:28 +01001453 writable).
Robert Tsai81ae1952007-12-05 10:47:29 +01001454
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01001455 - A file descriptor number in the form "fd@<number>", which may point
1456 to a pipe, terminal, or socket. In this case unbuffered logs are used
1457 and one writev() call per log is performed. This is a bit expensive
1458 but acceptable for most workloads. Messages sent this way will not be
1459 truncated but may be dropped, in which case the DroppedLogs counter
1460 will be incremented. The writev() call is atomic even on pipes for
1461 messages up to PIPE_BUF size, which POSIX recommends to be at least
1462 512 and which is 4096 bytes on most modern operating systems. Any
1463 larger message may be interleaved with messages from other processes.
1464 Exceptionally for debugging purposes the file descriptor may also be
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001465 directed to a file, but doing so will significantly slow HAProxy down
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01001466 as non-blocking calls will be ignored. Also there will be no way to
1467 purge nor rotate this file without restarting the process. Note that
1468 the configured syslog format is preserved, so the output is suitable
Willy Tarreauc1b06452018-11-12 11:57:56 +01001469 for use with a TCP syslog server. See also the "short" and "raw"
1470 format below.
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01001471
1472 - "stdout" / "stderr", which are respectively aliases for "fd@1" and
1473 "fd@2", see above.
1474
Willy Tarreauc046d162019-08-30 15:24:59 +02001475 - A ring buffer in the form "ring@<name>", which will correspond to an
1476 in-memory ring buffer accessible over the CLI using the "show events"
1477 command, which will also list existing rings and their sizes. Such
1478 buffers are lost on reload or restart but when used as a complement
1479 this can help troubleshooting by having the logs instantly available.
1480
William Lallemandb2f07452015-05-12 14:27:13 +02001481 You may want to reference some environment variables in the address
1482 parameter, see section 2.3 about environment variables.
Willy Tarreaudad36a32013-03-11 01:20:04 +01001483
Willy Tarreau18324f52014-06-27 18:10:07 +02001484 <length> is an optional maximum line length. Log lines larger than this value
1485 will be truncated before being sent. The reason is that syslog
1486 servers act differently on log line length. All servers support the
1487 default value of 1024, but some servers simply drop larger lines
1488 while others do log them. If a server supports long lines, it may
1489 make sense to set this value here in order to avoid truncating long
1490 lines. Similarly, if a server drops long lines, it is preferable to
1491 truncate them before sending them. Accepted values are 80 to 65535
1492 inclusive. The default value of 1024 is generally fine for all
1493 standard usages. Some specific cases of long captures or
Davor Ocelice9ed2812017-12-25 17:49:28 +01001494 JSON-formatted logs may require larger values. You may also need to
1495 increase "tune.http.logurilen" if your request URIs are truncated.
Willy Tarreau18324f52014-06-27 18:10:07 +02001496
Dragan Dosen7ad31542015-09-28 17:16:47 +02001497 <format> is the log format used when generating syslog messages. It may be
1498 one of the following :
1499
Emeric Brun0237c4e2020-11-27 16:24:34 +01001500 local Analog to rfc3164 syslog message format except that hostname
1501 field is stripped. This is the default.
1502 Note: option "log-send-hostname" switches the default to
1503 rfc3164.
1504
1505 rfc3164 The RFC3164 syslog message format.
Dragan Dosen7ad31542015-09-28 17:16:47 +02001506 (https://tools.ietf.org/html/rfc3164)
1507
1508 rfc5424 The RFC5424 syslog message format.
1509 (https://tools.ietf.org/html/rfc5424)
1510
Emeric Brun54648852020-07-06 15:54:06 +02001511 priority A message containing only a level plus syslog facility between
1512 angle brackets such as '<63>', followed by the text. The PID,
1513 date, time, process name and system name are omitted. This is
1514 designed to be used with a local log server.
1515
Willy Tarreaue8746a02018-11-12 08:45:00 +01001516 short A message containing only a level between angle brackets such as
1517 '<3>', followed by the text. The PID, date, time, process name
1518 and system name are omitted. This is designed to be used with a
1519 local log server. This format is compatible with what the systemd
1520 logger consumes.
1521
Emeric Brun54648852020-07-06 15:54:06 +02001522 timed A message containing only a level between angle brackets such as
1523 '<3>', followed by ISO date and by the text. The PID, process
1524 name and system name are omitted. This is designed to be
1525 used with a local log server.
1526
1527 iso A message containing only the ISO date, followed by the text.
1528 The PID, process name and system name are omitted. This is
1529 designed to be used with a local log server.
1530
Willy Tarreauc1b06452018-11-12 11:57:56 +01001531 raw A message containing only the text. The level, PID, date, time,
1532 process name and system name are omitted. This is designed to be
1533 used in containers or during development, where the severity only
1534 depends on the file descriptor used (stdout/stderr).
1535
Frédéric Lécailled690dfa2019-04-25 10:52:17 +02001536 <ranges> A list of comma-separated ranges to identify the logs to sample.
1537 This is used to balance the load of the logs to send to the log
1538 server. The limits of the ranges cannot be null. They are numbered
1539 from 1. The size or period (in number of logs) of the sample must be
1540 set with <sample_size> parameter.
1541
1542 <sample_size>
1543 The size of the sample in number of logs to consider when balancing
1544 their logging loads. It is used to balance the load of the logs to
1545 send to the syslog server. This size must be greater or equal to the
1546 maximum of the high limits of the ranges.
1547 (see also <ranges> parameter).
1548
Robert Tsai81ae1952007-12-05 10:47:29 +01001549 <facility> must be one of the 24 standard syslog facilities :
Willy Tarreau6a06a402007-07-15 20:15:28 +02001550
Willy Tarreaue8746a02018-11-12 08:45:00 +01001551 kern user mail daemon auth syslog lpr news
1552 uucp cron auth2 ftp ntp audit alert cron2
1553 local0 local1 local2 local3 local4 local5 local6 local7
1554
Willy Tarreauc1b06452018-11-12 11:57:56 +01001555 Note that the facility is ignored for the "short" and "raw"
1556 formats, but still required as a positional field. It is
1557 recommended to use "daemon" in this case to make it clear that
1558 it's only supposed to be used locally.
Willy Tarreau6a06a402007-07-15 20:15:28 +02001559
1560 An optional level can be specified to filter outgoing messages. By default,
Willy Tarreauf7edefa2009-05-10 17:20:05 +02001561 all messages are sent. If a maximum level is specified, only messages with a
1562 severity at least as important as this level will be sent. An optional minimum
1563 level can be specified. If it is set, logs emitted with a more severe level
1564 than this one will be capped to this level. This is used to avoid sending
1565 "emerg" messages on all terminals on some default syslog configurations.
1566 Eight levels are known :
Willy Tarreau6a06a402007-07-15 20:15:28 +02001567
Cyril Bontédc4d9032012-04-08 21:57:39 +02001568 emerg alert crit err warning notice info debug
Willy Tarreau6a06a402007-07-15 20:15:28 +02001569
Joe Williamsdf5b38f2010-12-29 17:05:48 +01001570log-send-hostname [<string>]
1571 Sets the hostname field in the syslog header. If optional "string" parameter
1572 is set the header is set to the string contents, otherwise uses the hostname
1573 of the system. Generally used if one is not relaying logs through an
1574 intermediate syslog server or for simply customizing the hostname printed in
1575 the logs.
1576
Kevinm48936af2010-12-22 16:08:21 +00001577log-tag <string>
1578 Sets the tag field in the syslog header to this string. It defaults to the
1579 program name as launched from the command line, which usually is "haproxy".
1580 Sometimes it can be useful to differentiate between multiple processes
Willy Tarreau094af4e2015-01-07 15:03:42 +01001581 running on the same host. See also the per-proxy "log-tag" directive.
Kevinm48936af2010-12-22 16:08:21 +00001582
Thierry FOURNIER90da1912015-03-05 11:17:06 +01001583lua-load <file>
Thierry Fournier59f11be2020-11-29 00:37:41 +01001584 This global directive loads and executes a Lua file in the shared context
1585 that is visible to all threads. Any variable set in such a context is visible
1586 from any thread. This is the easiest and recommended way to load Lua programs
1587 but it will not scale well if a lot of Lua calls are performed, as only one
1588 thread may be running on the global state at a time. A program loaded this
1589 way will always see 0 in the "core.thread" variable. This directive can be
Thierry FOURNIER90da1912015-03-05 11:17:06 +01001590 used multiple times.
1591
Thierry Fournier59f11be2020-11-29 00:37:41 +01001592lua-load-per-thread <file>
1593 This global directive loads and executes a Lua file into each started thread.
1594 Any global variable has a thread-local visibility so that each thread could
1595 see a different value. As such it is strongly recommended not to use global
1596 variables in programs loaded this way. An independent copy is loaded and
1597 initialized for each thread, everything is done sequentially and in the
1598 thread's numeric order from 1 to nbthread. If some operations need to be
1599 performed only once, the program should check the "core.thread" variable to
1600 figure what thread is being initialized. Programs loaded this way will run
1601 concurrently on all threads and will be highly scalable. This is the
1602 recommended way to load simple functions that register sample-fetches,
1603 converters, actions or services once it is certain the program doesn't depend
1604 on global variables. For the sake of simplicity, the directive is available
1605 even if only one thread is used and even if threads are disabled (in which
1606 case it will be equivalent to lua-load). This directive can be used multiple
1607 times.
1608
Tim Duesterhusdd74b5f2020-01-12 13:55:40 +01001609lua-prepend-path <string> [<type>]
1610 Prepends the given string followed by a semicolon to Lua's package.<type>
1611 variable.
1612 <type> must either be "path" or "cpath". If <type> is not given it defaults
1613 to "path".
1614
1615 Lua's paths are semicolon delimited lists of patterns that specify how the
1616 `require` function attempts to find the source file of a library. Question
1617 marks (?) within a pattern will be replaced by module name. The path is
1618 evaluated left to right. This implies that paths that are prepended later
1619 will be checked earlier.
1620
1621 As an example by specifying the following path:
1622
1623 lua-prepend-path /usr/share/haproxy-lua/?/init.lua
1624 lua-prepend-path /usr/share/haproxy-lua/?.lua
1625
1626 When `require "example"` is being called Lua will first attempt to load the
1627 /usr/share/haproxy-lua/example.lua script, if that does not exist the
1628 /usr/share/haproxy-lua/example/init.lua will be attempted and the default
1629 paths if that does not exist either.
1630
1631 See https://www.lua.org/pil/8.1.html for the details within the Lua
1632 documentation.
1633
William Lallemand4cfede82017-11-24 22:02:34 +01001634master-worker [no-exit-on-failure]
William Lallemande202b1e2017-06-01 17:38:56 +02001635 Master-worker mode. It is equivalent to the command line "-W" argument.
1636 This mode will launch a "master" which will monitor the "workers". Using
1637 this mode, you can reload HAProxy directly by sending a SIGUSR2 signal to
Davor Ocelice9ed2812017-12-25 17:49:28 +01001638 the master. The master-worker mode is compatible either with the foreground
William Lallemande202b1e2017-06-01 17:38:56 +02001639 or daemon mode. It is recommended to use this mode with multiprocess and
1640 systemd.
William Lallemand4cfede82017-11-24 22:02:34 +01001641 By default, if a worker exits with a bad return code, in the case of a
1642 segfault for example, all workers will be killed, and the master will leave.
1643 It is convenient to combine this behavior with Restart=on-failure in a
1644 systemd unit file in order to relaunch the whole process. If you don't want
1645 this behavior, you must use the keyword "no-exit-on-failure".
William Lallemande202b1e2017-06-01 17:38:56 +02001646
William Lallemand4cfede82017-11-24 22:02:34 +01001647 See also "-W" in the management guide.
William Lallemande202b1e2017-06-01 17:38:56 +02001648
William Lallemand27edc4b2019-05-07 17:49:33 +02001649mworker-max-reloads <number>
1650 In master-worker mode, this option limits the number of time a worker can
John Roeslerfb2fce12019-07-10 15:45:51 -05001651 survive to a reload. If the worker did not leave after a reload, once its
William Lallemand27edc4b2019-05-07 17:49:33 +02001652 number of reloads is greater than this number, the worker will receive a
1653 SIGTERM. This option helps to keep under control the number of workers.
1654 See also "show proc" in the Management Guide.
1655
Willy Tarreauf42d7942020-10-20 11:54:49 +02001656nbproc <number> (deprecated)
Willy Tarreau6a06a402007-07-15 20:15:28 +02001657 Creates <number> processes when going daemon. This requires the "daemon"
1658 mode. By default, only one process is created, which is the recommended mode
1659 of operation. For systems limited to small sets of file descriptors per
Willy Tarreau149ab772019-01-26 14:27:06 +01001660 process, it may be needed to fork multiple daemons. When set to a value
1661 larger than 1, threads are automatically disabled. USING MULTIPLE PROCESSES
Willy Tarreauf42d7942020-10-20 11:54:49 +02001662 IS HARDER TO DEBUG AND IS REALLY DISCOURAGED. This directive is deprecated
1663 and scheduled for removal in 2.5. Please use "nbthread" instead. See also
1664 "daemon" and "nbthread".
Willy Tarreau6a06a402007-07-15 20:15:28 +02001665
Christopher Fauletbe0faa22017-08-29 15:37:10 +02001666nbthread <number>
1667 This setting is only available when support for threads was built in. It
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001668 makes HAProxy run on <number> threads. This is exclusive with "nbproc". While
Willy Tarreau26f6ae12019-02-02 12:56:15 +01001669 "nbproc" historically used to be the only way to use multiple processors, it
1670 also involved a number of shortcomings related to the lack of synchronization
1671 between processes (health-checks, peers, stick-tables, stats, ...) which do
1672 not affect threads. As such, any modern configuration is strongly encouraged
Willy Tarreau149ab772019-01-26 14:27:06 +01001673 to migrate away from "nbproc" to "nbthread". "nbthread" also works when
1674 HAProxy is started in foreground. On some platforms supporting CPU affinity,
1675 when nbproc is not used, the default "nbthread" value is automatically set to
1676 the number of CPUs the process is bound to upon startup. This means that the
1677 thread count can easily be adjusted from the calling process using commands
1678 like "taskset" or "cpuset". Otherwise, this value defaults to 1. The default
1679 value is reported in the output of "haproxy -vv". See also "nbproc".
Christopher Fauletbe0faa22017-08-29 15:37:10 +02001680
Amaury Denoyelle0f50cb92021-03-26 18:50:33 +01001681numa-cpu-mapping
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001682 By default, if running on Linux, HAProxy inspects on startup the CPU topology
Amaury Denoyelle0f50cb92021-03-26 18:50:33 +01001683 of the machine. If a multi-socket machine is detected, the affinity is
1684 automatically calculated to run on the CPUs of a single node. This is done in
1685 order to not suffer from the performance penalties caused by the inter-socket
1686 bus latency. However, if the applied binding is non optimal on a particular
1687 architecture, it can be disabled with the statement 'no numa-cpu-mapping'.
1688 This automatic binding is also not applied if a nbthread statement is present
1689 in the configuration, or the affinity of the process is already specified,
1690 for example via the 'cpu-map' directive or the taskset utility.
1691
Willy Tarreau6a06a402007-07-15 20:15:28 +02001692pidfile <pidfile>
MIZUTA Takeshic32f3942020-08-26 13:46:19 +09001693 Writes PIDs of all daemons into file <pidfile> when daemon mode or writes PID
1694 of master process into file <pidfile> when master-worker mode. This option is
1695 equivalent to the "-p" command line argument. The file must be accessible to
1696 the user starting the process. See also "daemon" and "master-worker".
Willy Tarreau6a06a402007-07-15 20:15:28 +02001697
Willy Tarreau119e50e2020-05-22 13:53:29 +02001698pp2-never-send-local
1699 A bug in the PROXY protocol v2 implementation was present in HAProxy up to
1700 version 2.1, causing it to emit a PROXY command instead of a LOCAL command
1701 for health checks. This is particularly minor but confuses some servers'
1702 logs. Sadly, the bug was discovered very late and revealed that some servers
1703 which possibly only tested their PROXY protocol implementation against
1704 HAProxy fail to properly handle the LOCAL command, and permanently remain in
1705 the "down" state when HAProxy checks them. When this happens, it is possible
1706 to enable this global option to revert to the older (bogus) behavior for the
1707 time it takes to contact the affected components' vendors and get them fixed.
1708 This option is disabled by default and acts on all servers having the
1709 "send-proxy-v2" statement.
1710
Willy Tarreau1d549722016-02-16 12:41:57 +01001711presetenv <name> <value>
1712 Sets environment variable <name> to value <value>. If the variable exists, it
1713 is NOT overwritten. The changes immediately take effect so that the next line
1714 in the configuration file sees the new value. See also "setenv", "resetenv",
1715 and "unsetenv".
1716
1717resetenv [<name> ...]
1718 Removes all environment variables except the ones specified in argument. It
1719 allows to use a clean controlled environment before setting new values with
1720 setenv or unsetenv. Please note that some internal functions may make use of
1721 some environment variables, such as time manipulation functions, but also
1722 OpenSSL or even external checks. This must be used with extreme care and only
1723 after complete validation. The changes immediately take effect so that the
1724 next line in the configuration file sees the new environment. See also
1725 "setenv", "presetenv", and "unsetenv".
1726
Christopher Fauletff4121f2017-11-22 16:38:49 +01001727stats bind-process [ all | odd | even | <process_num>[-[process_num>]] ] ...
Willy Tarreau35b7b162012-10-22 23:17:18 +02001728 Limits the stats socket to a certain set of processes numbers. By default the
1729 stats socket is bound to all processes, causing a warning to be emitted when
1730 nbproc is greater than 1 because there is no way to select the target process
1731 when connecting. However, by using this setting, it becomes possible to pin
1732 the stats socket to a specific set of processes, typically the first one. The
1733 warning will automatically be disabled when this setting is used, whatever
Willy Tarreaua9db57e2013-01-18 11:29:29 +01001734 the number of processes used. The maximum process ID depends on the machine's
Christopher Fauletff4121f2017-11-22 16:38:49 +01001735 word size (32 or 64). Ranges can be partially defined. The higher bound can
1736 be omitted. In such case, it is replaced by the corresponding maximum
1737 value. A better option consists in using the "process" setting of the "stats
1738 socket" line to force the process on each line.
Willy Tarreau35b7b162012-10-22 23:17:18 +02001739
Baptiste Assmann5626f482015-08-23 10:00:10 +02001740server-state-base <directory>
1741 Specifies the directory prefix to be prepended in front of all servers state
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02001742 file names which do not start with a '/'. See also "server-state-file",
1743 "load-server-state-from-file" and "server-state-file-name".
Baptiste Assmannef1f0fc2015-08-23 10:06:39 +02001744
1745server-state-file <file>
1746 Specifies the path to the file containing state of servers. If the path starts
1747 with a slash ('/'), it is considered absolute, otherwise it is considered
1748 relative to the directory specified using "server-state-base" (if set) or to
1749 the current directory. Before reloading HAProxy, it is possible to save the
1750 servers' current state using the stats command "show servers state". The
1751 output of this command must be written in the file pointed by <file>. When
1752 starting up, before handling traffic, HAProxy will read, load and apply state
1753 for each server found in the file and available in its current running
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02001754 configuration. See also "server-state-base" and "show servers state",
1755 "load-server-state-from-file" and "server-state-file-name"
Baptiste Assmann5626f482015-08-23 10:00:10 +02001756
Willy Tarreau13d2ba22021-03-26 11:38:08 +01001757set-var <var-name> <expr>
1758 Sets the process-wide variable '<var-name>' to the result of the evaluation
1759 of the sample expression <expr>. The variable '<var-name>' may only be a
1760 process-wide variable (using the 'proc.' prefix). It works exactly like the
1761 'set-var' action in TCP or HTTP rules except that the expression is evaluated
1762 at configuration parsing time and that the variable is instantly set. The
1763 sample fetch functions and converters permitted in the expression are only
1764 those using internal data, typically 'int(value)' or 'str(value)'. It's is
1765 possible to reference previously allocated variables as well. These variables
1766 will then be readable (and modifiable) from the regular rule sets.
1767
1768 Example:
1769 global
1770 set-var proc.current_state str(primary)
1771 set-var proc.prio int(100)
1772 set-var proc.threshold int(200),sub(proc.prio)
1773
Willy Tarreau1d549722016-02-16 12:41:57 +01001774setenv <name> <value>
1775 Sets environment variable <name> to value <value>. If the variable exists, it
1776 is overwritten. The changes immediately take effect so that the next line in
1777 the configuration file sees the new value. See also "presetenv", "resetenv",
1778 and "unsetenv".
1779
Willy Tarreau636848a2019-04-15 19:38:50 +02001780set-dumpable
1781 This option is better left disabled by default and enabled only upon a
William Dauchyec730982019-10-27 20:08:10 +01001782 developer's request. If it has been enabled, it may still be forcibly
1783 disabled by prefixing it with the "no" keyword. It has no impact on
1784 performance nor stability but will try hard to re-enable core dumps that were
1785 possibly disabled by file size limitations (ulimit -f), core size limitations
1786 (ulimit -c), or "dumpability" of a process after changing its UID/GID (such
1787 as /proc/sys/fs/suid_dumpable on Linux). Core dumps might still be limited by
1788 the current directory's permissions (check what directory the file is started
1789 from), the chroot directory's permission (it may be needed to temporarily
1790 disable the chroot directive or to move it to a dedicated writable location),
1791 or any other system-specific constraint. For example, some Linux flavours are
1792 notorious for replacing the default core file with a path to an executable
1793 not even installed on the system (check /proc/sys/kernel/core_pattern). Often,
1794 simply writing "core", "core.%p" or "/var/log/core/core.%p" addresses the
1795 issue. When trying to enable this option waiting for a rare issue to
1796 re-appear, it's often a good idea to first try to obtain such a dump by
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001797 issuing, for example, "kill -11" to the "haproxy" process and verify that it
William Dauchyec730982019-10-27 20:08:10 +01001798 leaves a core where expected when dying.
Willy Tarreau636848a2019-04-15 19:38:50 +02001799
Willy Tarreau610f04b2014-02-13 11:36:41 +01001800ssl-default-bind-ciphers <ciphers>
1801 This setting is only available when support for OpenSSL was built in. It sets
1802 the default string describing the list of cipher algorithms ("cipher suite")
Bertrand Jacquin8cf7c1e2019-02-03 18:35:25 +00001803 that are negotiated during the SSL/TLS handshake up to TLSv1.2 for all
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001804 "bind" lines which do not explicitly define theirs. The format of the string
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +00001805 is defined in "man 1 ciphers" from OpenSSL man pages. For background
1806 information and recommendations see e.g.
1807 (https://wiki.mozilla.org/Security/Server_Side_TLS) and
1808 (https://mozilla.github.io/server-side-tls/ssl-config-generator/). For TLSv1.3
1809 cipher configuration, please check the "ssl-default-bind-ciphersuites" keyword.
1810 Please check the "bind" keyword for more information.
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001811
1812ssl-default-bind-ciphersuites <ciphersuites>
1813 This setting is only available when support for OpenSSL was built in and
1814 OpenSSL 1.1.1 or later was used to build HAProxy. It sets the default string
1815 describing the list of cipher algorithms ("cipher suite") that are negotiated
1816 during the TLSv1.3 handshake for all "bind" lines which do not explicitly define
1817 theirs. The format of the string is defined in
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +00001818 "man 1 ciphers" from OpenSSL man pages under the section "ciphersuites". For
1819 cipher configuration for TLSv1.2 and earlier, please check the
1820 "ssl-default-bind-ciphers" keyword. Please check the "bind" keyword for more
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001821 information.
Willy Tarreau610f04b2014-02-13 11:36:41 +01001822
Jerome Magninb203ff62020-04-03 15:28:22 +02001823ssl-default-bind-curves <curves>
1824 This setting is only available when support for OpenSSL was built in. It sets
1825 the default string describing the list of elliptic curves algorithms ("curve
1826 suite") that are negotiated during the SSL/TLS handshake with ECDHE. The format
1827 of the string is a colon-delimited list of curve name.
1828 Please check the "bind" keyword for more information.
1829
Emeric Brun2c86cbf2014-10-30 15:56:50 +01001830ssl-default-bind-options [<option>]...
1831 This setting is only available when support for OpenSSL was built in. It sets
1832 default ssl-options to force on all "bind" lines. Please check the "bind"
1833 keyword to see available options.
1834
1835 Example:
1836 global
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +02001837 ssl-default-bind-options ssl-min-ver TLSv1.0 no-tls-tickets
Emeric Brun2c86cbf2014-10-30 15:56:50 +01001838
Willy Tarreau610f04b2014-02-13 11:36:41 +01001839ssl-default-server-ciphers <ciphers>
1840 This setting is only available when support for OpenSSL was built in. It
1841 sets the default string describing the list of cipher algorithms that are
Bertrand Jacquin8cf7c1e2019-02-03 18:35:25 +00001842 negotiated during the SSL/TLS handshake up to TLSv1.2 with the server,
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001843 for all "server" lines which do not explicitly define theirs. The format of
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +00001844 the string is defined in "man 1 ciphers" from OpenSSL man pages. For background
1845 information and recommendations see e.g.
1846 (https://wiki.mozilla.org/Security/Server_Side_TLS) and
1847 (https://mozilla.github.io/server-side-tls/ssl-config-generator/).
1848 For TLSv1.3 cipher configuration, please check the
1849 "ssl-default-server-ciphersuites" keyword. Please check the "server" keyword
1850 for more information.
Dirkjan Bussink415150f2018-09-14 11:14:21 +02001851
1852ssl-default-server-ciphersuites <ciphersuites>
1853 This setting is only available when support for OpenSSL was built in and
1854 OpenSSL 1.1.1 or later was used to build HAProxy. It sets the default
1855 string describing the list of cipher algorithms that are negotiated during
1856 the TLSv1.3 handshake with the server, for all "server" lines which do not
1857 explicitly define theirs. The format of the string is defined in
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +00001858 "man 1 ciphers" from OpenSSL man pages under the section "ciphersuites". For
1859 cipher configuration for TLSv1.2 and earlier, please check the
1860 "ssl-default-server-ciphers" keyword. Please check the "server" keyword for
1861 more information.
Willy Tarreau610f04b2014-02-13 11:36:41 +01001862
Emeric Brun2c86cbf2014-10-30 15:56:50 +01001863ssl-default-server-options [<option>]...
1864 This setting is only available when support for OpenSSL was built in. It sets
1865 default ssl-options to force on all "server" lines. Please check the "server"
1866 keyword to see available options.
1867
Remi Gacogne47783ef2015-05-29 15:53:22 +02001868ssl-dh-param-file <file>
1869 This setting is only available when support for OpenSSL was built in. It sets
1870 the default DH parameters that are used during the SSL/TLS handshake when
1871 ephemeral Diffie-Hellman (DHE) key exchange is used, for all "bind" lines
Davor Ocelice9ed2812017-12-25 17:49:28 +01001872 which do not explicitly define theirs. It will be overridden by custom DH
Remi Gacogne47783ef2015-05-29 15:53:22 +02001873 parameters found in a bind certificate file if any. If custom DH parameters
Cyril Bonté307ee1e2015-09-28 23:16:06 +02001874 are not specified either by using ssl-dh-param-file or by setting them
1875 directly in the certificate file, pre-generated DH parameters of the size
1876 specified by tune.ssl.default-dh-param will be used. Custom parameters are
1877 known to be more secure and therefore their use is recommended.
Remi Gacogne47783ef2015-05-29 15:53:22 +02001878 Custom DH parameters may be generated by using the OpenSSL command
1879 "openssl dhparam <size>", where size should be at least 2048, as 1024-bit DH
1880 parameters should not be considered secure anymore.
1881
William Lallemand8e8581e2020-10-20 17:36:46 +02001882ssl-load-extra-del-ext
1883 This setting allows to configure the way HAProxy does the lookup for the
1884 extra SSL files. By default HAProxy adds a new extension to the filename.
William Lallemand089c1382020-10-23 17:35:12 +02001885 (ex: with "foobar.crt" load "foobar.crt.key"). With this option enabled,
William Lallemand8e8581e2020-10-20 17:36:46 +02001886 HAProxy removes the extension before adding the new one (ex: with
William Lallemand089c1382020-10-23 17:35:12 +02001887 "foobar.crt" load "foobar.key").
1888
1889 Your crt file must have a ".crt" extension for this option to work.
William Lallemand8e8581e2020-10-20 17:36:46 +02001890
1891 This option is not compatible with bundle extensions (.ecdsa, .rsa. .dsa)
1892 and won't try to remove them.
1893
1894 This option is disabled by default. See also "ssl-load-extra-files".
1895
William Lallemand4c5adbf2020-02-24 14:23:22 +01001896ssl-load-extra-files <none|all|bundle|sctl|ocsp|issuer|key>*
William Lallemand3af48e72020-02-03 17:15:52 +01001897 This setting alters the way HAProxy will look for unspecified files during
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001898 the loading of the SSL certificates. This option applies to certificates
1899 associated to "bind" lines as well as "server" lines but some of the extra
1900 files will not have any functional impact for "server" line certificates.
William Lallemand3af48e72020-02-03 17:15:52 +01001901
1902 By default, HAProxy discovers automatically a lot of files not specified in
1903 the configuration, and you may want to disable this behavior if you want to
1904 optimize the startup time.
1905
1906 "none": Only load the files specified in the configuration. Don't try to load
1907 a certificate bundle if the file does not exist. In the case of a directory,
1908 it won't try to bundle the certificates if they have the same basename.
1909
1910 "all": This is the default behavior, it will try to load everything,
William Lallemand4c5adbf2020-02-24 14:23:22 +01001911 bundles, sctl, ocsp, issuer, key.
William Lallemand3af48e72020-02-03 17:15:52 +01001912
1913 "bundle": When a file specified in the configuration does not exist, HAProxy
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001914 will try to load a "cert bundle". Certificate bundles are only managed on the
1915 frontend side and will not work for backend certificates.
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001916
1917 Starting from HAProxy 2.3, the bundles are not loaded in the same OpenSSL
1918 certificate store, instead it will loads each certificate in a separate
1919 store which is equivalent to declaring multiple "crt". OpenSSL 1.1.1 is
1920 required to achieve this. Which means that bundles are now used only for
1921 backward compatibility and are not mandatory anymore to do an hybrid RSA/ECC
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001922 bind configuration.
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001923
1924 To associate these PEM files into a "cert bundle" that is recognized by
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001925 HAProxy, they must be named in the following way: All PEM files that are to
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001926 be bundled must have the same base name, with a suffix indicating the key
1927 type. Currently, three suffixes are supported: rsa, dsa and ecdsa. For
1928 example, if www.example.com has two PEM files, an RSA file and an ECDSA
1929 file, they must be named: "example.pem.rsa" and "example.pem.ecdsa". The
1930 first part of the filename is arbitrary; only the suffix matters. To load
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001931 this bundle into HAProxy, specify the base name only:
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001932
1933 Example : bind :8443 ssl crt example.pem
1934
Daniel Corbett9f0843f2021-05-08 10:50:37 -04001935 Note that the suffix is not given to HAProxy; this tells HAProxy to look for
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001936 a cert bundle.
1937
1938 HAProxy will load all PEM files in the bundle as if they were configured
1939 separately in several "crt".
1940
1941 The bundle loading does not have an impact anymore on the directory loading
1942 since files are loading separately.
1943
1944 On the CLI, bundles are seen as separate files, and the bundle extension is
1945 required to commit them.
1946
William Dauchy57dd6f12020-10-06 15:22:37 +02001947 OCSP files (.ocsp), issuer files (.issuer), Certificate Transparency (.sctl)
William Lallemandf9ff3ec2020-10-02 17:57:44 +02001948 as well as private keys (.key) are supported with multi-cert bundling.
William Lallemand3af48e72020-02-03 17:15:52 +01001949
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001950 "sctl": Try to load "<basename>.sctl" for each crt keyword. If provided for
1951 a backend certificate, it will be loaded but will not have any functional
1952 impact.
William Lallemand3af48e72020-02-03 17:15:52 +01001953
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001954 "ocsp": Try to load "<basename>.ocsp" for each crt keyword. If provided for
1955 a backend certificate, it will be loaded but will not have any functional
1956 impact.
William Lallemand3af48e72020-02-03 17:15:52 +01001957
1958 "issuer": Try to load "<basename>.issuer" if the issuer of the OCSP file is
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001959 not provided in the PEM file. If provided for a backend certificate, it will
1960 be loaded but will not have any functional impact.
William Lallemand3af48e72020-02-03 17:15:52 +01001961
William Lallemand4c5adbf2020-02-24 14:23:22 +01001962 "key": If the private key was not provided by the PEM file, try to load a
1963 file "<basename>.key" containing a private key.
1964
William Lallemand3af48e72020-02-03 17:15:52 +01001965 The default behavior is "all".
1966
1967 Example:
1968 ssl-load-extra-files bundle sctl
1969 ssl-load-extra-files sctl ocsp issuer
1970 ssl-load-extra-files none
1971
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +02001972 See also: "crt", section 5.1 about bind options and section 5.2 about server
1973 options.
William Lallemand3af48e72020-02-03 17:15:52 +01001974
Emeric Brun850efd52014-01-29 12:24:34 +01001975ssl-server-verify [none|required]
1976 The default behavior for SSL verify on servers side. If specified to 'none',
1977 servers certificates are not verified. The default is 'required' except if
1978 forced using cmdline option '-dV'.
1979
Emmanuel Hocdetc3b7e742020-04-22 11:06:19 +02001980ssl-skip-self-issued-ca
Daniel Corbett67a82712020-07-06 23:01:19 -04001981 Self issued CA, aka x509 root CA, is the anchor for chain validation: as a
Emmanuel Hocdetc3b7e742020-04-22 11:06:19 +02001982 server is useless to send it, client must have it. Standard configuration
1983 need to not include such CA in PEM file. This option allows you to keep such
1984 CA in PEM file without sending it to the client. Use case is to provide
1985 issuer for ocsp without the need for '.issuer' file and be able to share it
1986 with 'issuers-chain-path'. This concerns all certificates without intermediate
1987 certificates. It's useless for BoringSSL, .issuer is ignored because ocsp
William Lallemand9a1d8392020-08-10 17:28:23 +02001988 bits does not need it. Requires at least OpenSSL 1.0.2.
Emmanuel Hocdetc3b7e742020-04-22 11:06:19 +02001989
Willy Tarreauabb175f2012-09-24 12:43:26 +02001990stats socket [<address:port>|<path>] [param*]
1991 Binds a UNIX socket to <path> or a TCPv4/v6 address to <address:port>.
1992 Connections to this socket will return various statistics outputs and even
1993 allow some commands to be issued to change some runtime settings. Please
Willy Tarreau1af20c72017-06-23 16:01:14 +02001994 consult section 9.3 "Unix Socket commands" of Management Guide for more
Kevin Decherf949c7202015-10-13 23:26:44 +02001995 details.
Willy Tarreau6162db22009-10-10 17:13:00 +02001996
Willy Tarreauabb175f2012-09-24 12:43:26 +02001997 All parameters supported by "bind" lines are supported, for instance to
1998 restrict access to some users or their access rights. Please consult
1999 section 5.1 for more information.
Willy Tarreaufbee7132007-10-18 13:53:22 +02002000
2001stats timeout <timeout, in milliseconds>
2002 The default timeout on the stats socket is set to 10 seconds. It is possible
2003 to change this value with "stats timeout". The value must be passed in
Willy Tarreaubefdff12007-12-02 22:27:38 +01002004 milliseconds, or be suffixed by a time unit among { us, ms, s, m, h, d }.
Willy Tarreaufbee7132007-10-18 13:53:22 +02002005
2006stats maxconn <connections>
2007 By default, the stats socket is limited to 10 concurrent connections. It is
2008 possible to change this value with "stats maxconn".
2009
Willy Tarreau6a06a402007-07-15 20:15:28 +02002010uid <number>
Thayne McCombscdbcca92021-01-07 21:24:41 -07002011 Changes the process's user ID to <number>. It is recommended that the user ID
Willy Tarreau6a06a402007-07-15 20:15:28 +02002012 is dedicated to HAProxy or to a small set of similar daemons. HAProxy must
2013 be started with superuser privileges in order to be able to switch to another
2014 one. See also "gid" and "user".
2015
2016ulimit-n <number>
2017 Sets the maximum number of per-process file-descriptors to <number>. By
2018 default, it is automatically computed, so it is recommended not to use this
2019 option.
2020
Willy Tarreauceb24bc2010-11-09 12:46:41 +01002021unix-bind [ prefix <prefix> ] [ mode <mode> ] [ user <user> ] [ uid <uid> ]
2022 [ group <group> ] [ gid <gid> ]
2023
2024 Fixes common settings to UNIX listening sockets declared in "bind" statements.
2025 This is mainly used to simplify declaration of those UNIX sockets and reduce
2026 the risk of errors, since those settings are most commonly required but are
2027 also process-specific. The <prefix> setting can be used to force all socket
2028 path to be relative to that directory. This might be needed to access another
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002029 component's chroot. Note that those paths are resolved before HAProxy chroots
Willy Tarreauceb24bc2010-11-09 12:46:41 +01002030 itself, so they are absolute. The <mode>, <user>, <uid>, <group> and <gid>
2031 all have the same meaning as their homonyms used by the "bind" statement. If
2032 both are specified, the "bind" statement has priority, meaning that the
2033 "unix-bind" settings may be seen as process-wide default settings.
2034
Willy Tarreau1d549722016-02-16 12:41:57 +01002035unsetenv [<name> ...]
2036 Removes environment variables specified in arguments. This can be useful to
2037 hide some sensitive information that are occasionally inherited from the
2038 user's environment during some operations. Variables which did not exist are
2039 silently ignored so that after the operation, it is certain that none of
2040 these variables remain. The changes immediately take effect so that the next
2041 line in the configuration file will not see these variables. See also
2042 "setenv", "presetenv", and "resetenv".
2043
Willy Tarreau6a06a402007-07-15 20:15:28 +02002044user <user name>
2045 Similar to "uid" but uses the UID of user name <user name> from /etc/passwd.
2046 See also "uid" and "group".
2047
Krzysztof Piotr Oledzki48cb2ae2009-10-02 22:51:14 +02002048node <name>
2049 Only letters, digits, hyphen and underscore are allowed, like in DNS names.
2050
2051 This statement is useful in HA configurations where two or more processes or
2052 servers share the same IP address. By setting a different node-name on all
2053 nodes, it becomes easy to immediately spot what server is handling the
2054 traffic.
2055
2056description <text>
2057 Add a text that describes the instance.
2058
2059 Please note that it is required to escape certain characters (# for example)
2060 and this text is inserted into a html page so you should avoid using
2061 "<" and ">" characters.
2062
Thomas Holmesdb04f192015-05-18 13:21:39 +0100206351degrees-data-file <file path>
2064 The path of the 51Degrees data file to provide device detection services. The
Davor Ocelice9ed2812017-12-25 17:49:28 +01002065 file should be unzipped and accessible by HAProxy with relevant permissions.
Thomas Holmesdb04f192015-05-18 13:21:39 +01002066
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002067 Please note that this option is only available when HAProxy has been
Thomas Holmesdb04f192015-05-18 13:21:39 +01002068 compiled with USE_51DEGREES.
2069
Ben Shillitof25e8e52016-12-02 14:25:37 +0000207051degrees-property-name-list [<string> ...]
Thomas Holmesdb04f192015-05-18 13:21:39 +01002071 A list of 51Degrees property names to be load from the dataset. A full list
2072 of names is available on the 51Degrees website:
2073 https://51degrees.com/resources/property-dictionary
2074
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002075 Please note that this option is only available when HAProxy has been
Thomas Holmesdb04f192015-05-18 13:21:39 +01002076 compiled with USE_51DEGREES.
2077
Dragan Dosen93b38d92015-06-29 16:43:25 +0200207851degrees-property-separator <char>
Thomas Holmesdb04f192015-05-18 13:21:39 +01002079 A char that will be appended to every property value in a response header
2080 containing 51Degrees results. If not set that will be set as ','.
2081
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002082 Please note that this option is only available when HAProxy has been
Dragan Dosenae6d39a2015-06-29 16:43:27 +02002083 compiled with USE_51DEGREES.
2084
208551degrees-cache-size <number>
2086 Sets the size of the 51Degrees converter cache to <number> entries. This
2087 is an LRU cache which reminds previous device detections and their results.
2088 By default, this cache is disabled.
2089
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002090 Please note that this option is only available when HAProxy has been
Thomas Holmesdb04f192015-05-18 13:21:39 +01002091 compiled with USE_51DEGREES.
2092
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002093wurfl-data-file <file path>
2094 The path of the WURFL data file to provide device detection services. The
2095 file should be accessible by HAProxy with relevant permissions.
2096
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002097 Please note that this option is only available when HAProxy has been compiled
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002098 with USE_WURFL=1.
2099
2100wurfl-information-list [<capability>]*
2101 A space-delimited list of WURFL capabilities, virtual capabilities, property
2102 names we plan to use in injected headers. A full list of capability and
2103 virtual capability names is available on the Scientiamobile website :
2104
2105 https://www.scientiamobile.com/wurflCapability
2106
2107 Valid WURFL properties are:
2108 - wurfl_id Contains the device ID of the matched device.
2109
2110 - wurfl_root_id Contains the device root ID of the matched
2111 device.
2112
2113 - wurfl_isdevroot Tells if the matched device is a root device.
2114 Possible values are "TRUE" or "FALSE".
2115
2116 - wurfl_useragent The original useragent coming with this
2117 particular web request.
2118
2119 - wurfl_api_version Contains a string representing the currently
2120 used Libwurfl API version.
2121
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002122 - wurfl_info A string containing information on the parsed
2123 wurfl.xml and its full path.
2124
2125 - wurfl_last_load_time Contains the UNIX timestamp of the last time
2126 WURFL has been loaded successfully.
2127
2128 - wurfl_normalized_useragent The normalized useragent.
2129
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002130 Please note that this option is only available when HAProxy has been compiled
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002131 with USE_WURFL=1.
2132
2133wurfl-information-list-separator <char>
2134 A char that will be used to separate values in a response header containing
2135 WURFL results. If not set that a comma (',') will be used by default.
2136
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002137 Please note that this option is only available when HAProxy has been compiled
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002138 with USE_WURFL=1.
2139
2140wurfl-patch-file [<file path>]
2141 A list of WURFL patch file paths. Note that patches are loaded during startup
2142 thus before the chroot.
2143
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002144 Please note that this option is only available when HAProxy has been compiled
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002145 with USE_WURFL=1.
2146
paulborilebad132c2019-04-18 11:57:04 +02002147wurfl-cache-size <size>
2148 Sets the WURFL Useragent cache size. For faster lookups, already processed user
2149 agents are kept in a LRU cache :
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002150 - "0" : no cache is used.
paulborilebad132c2019-04-18 11:57:04 +02002151 - <size> : size of lru cache in elements.
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002152
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002153 Please note that this option is only available when HAProxy has been compiled
Willy Tarreaub3cc9f22019-04-19 16:03:32 +02002154 with USE_WURFL=1.
2155
William Dauchy0fec3ab2019-10-27 20:08:11 +01002156strict-limits
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002157 Makes process fail at startup when a setrlimit fails. HAProxy tries to set the
William Dauchya5194602020-03-28 19:29:58 +01002158 best setrlimit according to what has been calculated. If it fails, it will
2159 emit a warning. This option is here to guarantee an explicit failure of
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002160 HAProxy when those limits fail. It is enabled by default. It may still be
William Dauchya5194602020-03-28 19:29:58 +01002161 forcibly disabled by prefixing it with the "no" keyword.
William Dauchy0fec3ab2019-10-27 20:08:11 +01002162
Willy Tarreauc57f0e22009-05-10 13:12:33 +020021633.2. Performance tuning
Willy Tarreau6a06a402007-07-15 20:15:28 +02002164-----------------------
2165
Willy Tarreaubeb859a2018-11-22 18:07:59 +01002166busy-polling
2167 In some situations, especially when dealing with low latency on processors
2168 supporting a variable frequency or when running inside virtual machines, each
2169 time the process waits for an I/O using the poller, the processor goes back
2170 to sleep or is offered to another VM for a long time, and it causes
2171 excessively high latencies. This option provides a solution preventing the
2172 processor from sleeping by always using a null timeout on the pollers. This
2173 results in a significant latency reduction (30 to 100 microseconds observed)
2174 at the expense of a risk to overheat the processor. It may even be used with
2175 threads, in which case improperly bound threads may heavily conflict,
2176 resulting in a worse performance and high values for the CPU stolen fields
2177 in "show info" output, indicating which threads are misconfigured. It is
2178 important not to let the process run on the same processor as the network
2179 interrupts when this option is used. It is also better to avoid using it on
2180 multiple CPU threads sharing the same core. This option is disabled by
2181 default. If it has been enabled, it may still be forcibly disabled by
2182 prefixing it with the "no" keyword. It is ignored by the "select" and
2183 "poll" pollers.
2184
William Dauchy3894d972019-12-28 15:36:02 +01002185 This option is automatically disabled on old processes in the context of
2186 seamless reload; it avoids too much cpu conflicts when multiple processes
2187 stay around for some time waiting for the end of their current connections.
2188
Willy Tarreau1746eec2014-04-25 10:46:47 +02002189max-spread-checks <delay in milliseconds>
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002190 By default, HAProxy tries to spread the start of health checks across the
Willy Tarreau1746eec2014-04-25 10:46:47 +02002191 smallest health check interval of all the servers in a farm. The principle is
2192 to avoid hammering services running on the same server. But when using large
2193 check intervals (10 seconds or more), the last servers in the farm take some
2194 time before starting to be tested, which can be a problem. This parameter is
2195 used to enforce an upper bound on delay between the first and the last check,
2196 even if the servers' check intervals are larger. When servers run with
2197 shorter intervals, their intervals will be respected though.
2198
Willy Tarreau6a06a402007-07-15 20:15:28 +02002199maxconn <number>
2200 Sets the maximum per-process number of concurrent connections to <number>. It
2201 is equivalent to the command-line argument "-n". Proxies will stop accepting
2202 connections when this limit is reached. The "ulimit-n" parameter is
Willy Tarreau8274e102014-06-19 15:31:25 +02002203 automatically adjusted according to this value. See also "ulimit-n". Note:
2204 the "select" poller cannot reliably use more than 1024 file descriptors on
2205 some platforms. If your platform only supports select and reports "select
2206 FAILED" on startup, you need to reduce maxconn until it works (slightly
Willy Tarreaub28f3442019-03-04 08:13:43 +01002207 below 500 in general). If this value is not set, it will automatically be
2208 calculated based on the current file descriptors limit reported by the
2209 "ulimit -n" command, possibly reduced to a lower value if a memory limit
2210 is enforced, based on the buffer size, memory allocated to compression, SSL
2211 cache size, and use or not of SSL and the associated maxsslconn (which can
2212 also be automatic).
Willy Tarreau6a06a402007-07-15 20:15:28 +02002213
Willy Tarreau81c25d02011-09-07 15:17:21 +02002214maxconnrate <number>
2215 Sets the maximum per-process number of connections per second to <number>.
2216 Proxies will stop accepting connections when this limit is reached. It can be
2217 used to limit the global capacity regardless of each frontend capacity. It is
2218 important to note that this can only be used as a service protection measure,
2219 as there will not necessarily be a fair share between frontends when the
2220 limit is reached, so it's a good idea to also limit each frontend to some
2221 value close to its expected share. Also, lowering tune.maxaccept can improve
2222 fairness.
2223
William Lallemandd85f9172012-11-09 17:05:39 +01002224maxcomprate <number>
2225 Sets the maximum per-process input compression rate to <number> kilobytes
Davor Ocelice9ed2812017-12-25 17:49:28 +01002226 per second. For each session, if the maximum is reached, the compression
William Lallemandd85f9172012-11-09 17:05:39 +01002227 level will be decreased during the session. If the maximum is reached at the
2228 beginning of a session, the session will not compress at all. If the maximum
2229 is not reached, the compression level will be increased up to
Davor Ocelice9ed2812017-12-25 17:49:28 +01002230 tune.comp.maxlevel. A value of zero means there is no limit, this is the
William Lallemandd85f9172012-11-09 17:05:39 +01002231 default value.
2232
William Lallemand072a2bf2012-11-20 17:01:01 +01002233maxcompcpuusage <number>
2234 Sets the maximum CPU usage HAProxy can reach before stopping the compression
2235 for new requests or decreasing the compression level of current requests.
2236 It works like 'maxcomprate' but measures CPU usage instead of incoming data
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002237 bandwidth. The value is expressed in percent of the CPU used by HAProxy. In
William Lallemand072a2bf2012-11-20 17:01:01 +01002238 case of multiple processes (nbproc > 1), each process manages its individual
2239 usage. A value of 100 disable the limit. The default value is 100. Setting
2240 a lower value will prevent the compression work from slowing the whole
2241 process down and from introducing high latencies.
2242
Willy Tarreauff4f82d2009-02-06 11:28:13 +01002243maxpipes <number>
2244 Sets the maximum per-process number of pipes to <number>. Currently, pipes
2245 are only used by kernel-based tcp splicing. Since a pipe contains two file
2246 descriptors, the "ulimit-n" value will be increased accordingly. The default
2247 value is maxconn/4, which seems to be more than enough for most heavy usages.
2248 The splice code dynamically allocates and releases pipes, and can fall back
2249 to standard copy, so setting this value too low may only impact performance.
2250
Willy Tarreau93e7c002013-10-07 18:51:07 +02002251maxsessrate <number>
2252 Sets the maximum per-process number of sessions per second to <number>.
2253 Proxies will stop accepting connections when this limit is reached. It can be
2254 used to limit the global capacity regardless of each frontend capacity. It is
2255 important to note that this can only be used as a service protection measure,
2256 as there will not necessarily be a fair share between frontends when the
2257 limit is reached, so it's a good idea to also limit each frontend to some
2258 value close to its expected share. Also, lowering tune.maxaccept can improve
2259 fairness.
2260
Willy Tarreau403edff2012-09-06 11:58:37 +02002261maxsslconn <number>
2262 Sets the maximum per-process number of concurrent SSL connections to
2263 <number>. By default there is no SSL-specific limit, which means that the
2264 global maxconn setting will apply to all connections. Setting this limit
2265 avoids having openssl use too much memory and crash when malloc returns NULL
2266 (since it unfortunately does not reliably check for such conditions). Note
2267 that the limit applies both to incoming and outgoing connections, so one
2268 connection which is deciphered then ciphered accounts for 2 SSL connections.
Willy Tarreaud0256482015-01-15 21:45:22 +01002269 If this value is not set, but a memory limit is enforced, this value will be
2270 automatically computed based on the memory limit, maxconn, the buffer size,
2271 memory allocated to compression, SSL cache size, and use of SSL in either
2272 frontends, backends or both. If neither maxconn nor maxsslconn are specified
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002273 when there is a memory limit, HAProxy will automatically adjust these values
Willy Tarreaud0256482015-01-15 21:45:22 +01002274 so that 100% of the connections can be made over SSL with no risk, and will
2275 consider the sides where it is enabled (frontend, backend, both).
Willy Tarreau403edff2012-09-06 11:58:37 +02002276
Willy Tarreaue43d5322013-10-07 20:01:52 +02002277maxsslrate <number>
2278 Sets the maximum per-process number of SSL sessions per second to <number>.
2279 SSL listeners will stop accepting connections when this limit is reached. It
2280 can be used to limit the global SSL CPU usage regardless of each frontend
2281 capacity. It is important to note that this can only be used as a service
2282 protection measure, as there will not necessarily be a fair share between
2283 frontends when the limit is reached, so it's a good idea to also limit each
2284 frontend to some value close to its expected share. It is also important to
2285 note that the sessions are accounted before they enter the SSL stack and not
2286 after, which also protects the stack against bad handshakes. Also, lowering
2287 tune.maxaccept can improve fairness.
2288
William Lallemand9d5f5482012-11-07 16:12:57 +01002289maxzlibmem <number>
2290 Sets the maximum amount of RAM in megabytes per process usable by the zlib.
2291 When the maximum amount is reached, future sessions will not compress as long
2292 as RAM is unavailable. When sets to 0, there is no limit.
William Lallemande3a7d992012-11-20 11:25:20 +01002293 The default value is 0. The value is available in bytes on the UNIX socket
2294 with "show info" on the line "MaxZlibMemUsage", the memory used by zlib is
2295 "ZlibMemUsage" in bytes.
2296
Willy Tarreau6a06a402007-07-15 20:15:28 +02002297noepoll
2298 Disables the use of the "epoll" event polling system on Linux. It is
2299 equivalent to the command-line argument "-de". The next polling system
Willy Tarreaue9f49e72012-11-11 17:42:00 +01002300 used will generally be "poll". See also "nopoll".
Willy Tarreau6a06a402007-07-15 20:15:28 +02002301
2302nokqueue
2303 Disables the use of the "kqueue" event polling system on BSD. It is
2304 equivalent to the command-line argument "-dk". The next polling system
2305 used will generally be "poll". See also "nopoll".
2306
Emmanuel Hocdet0ba4f482019-04-08 16:53:32 +00002307noevports
2308 Disables the use of the event ports event polling system on SunOS systems
2309 derived from Solaris 10 and later. It is equivalent to the command-line
2310 argument "-dv". The next polling system used will generally be "poll". See
2311 also "nopoll".
2312
Willy Tarreau6a06a402007-07-15 20:15:28 +02002313nopoll
2314 Disables the use of the "poll" event polling system. It is equivalent to the
2315 command-line argument "-dp". The next polling system used will be "select".
Willy Tarreau0ba27502007-12-24 16:55:16 +01002316 It should never be needed to disable "poll" since it's available on all
Emmanuel Hocdet0ba4f482019-04-08 16:53:32 +00002317 platforms supported by HAProxy. See also "nokqueue", "noepoll" and
2318 "noevports".
Willy Tarreau6a06a402007-07-15 20:15:28 +02002319
Willy Tarreauff4f82d2009-02-06 11:28:13 +01002320nosplice
2321 Disables the use of kernel tcp splicing between sockets on Linux. It is
Davor Ocelice9ed2812017-12-25 17:49:28 +01002322 equivalent to the command line argument "-dS". Data will then be copied
Willy Tarreauff4f82d2009-02-06 11:28:13 +01002323 using conventional and more portable recv/send calls. Kernel tcp splicing is
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01002324 limited to some very recent instances of kernel 2.6. Most versions between
Willy Tarreauff4f82d2009-02-06 11:28:13 +01002325 2.6.25 and 2.6.28 are buggy and will forward corrupted data, so they must not
2326 be used. This option makes it easier to globally disable kernel splicing in
2327 case of doubt. See also "option splice-auto", "option splice-request" and
2328 "option splice-response".
2329
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03002330nogetaddrinfo
2331 Disables the use of getaddrinfo(3) for name resolving. It is equivalent to
2332 the command line argument "-dG". Deprecated gethostbyname(3) will be used.
2333
Lukas Tribusa0bcbdc2016-09-12 21:42:20 +00002334noreuseport
2335 Disables the use of SO_REUSEPORT - see socket(7). It is equivalent to the
2336 command line argument "-dR".
2337
Willy Tarreauca3afc22021-05-05 18:33:19 +02002338profiling.memory { on | off }
2339 Enables ('on') or disables ('off') per-function memory profiling. This will
2340 keep usage statistics of malloc/calloc/realloc/free calls anywhere in the
2341 process (including libraries) which will be reported on the CLI using the
2342 "show profiling" command. This is essentially meant to be used when an
2343 abnormal memory usage is observed that cannot be explained by the pools and
2344 other info are required. The performance hit will typically be around 1%,
2345 maybe a bit more on highly threaded machines, so it is normally suitable for
2346 use in production. The same may be achieved at run time on the CLI using the
2347 "set profiling memory" command, please consult the management manual.
2348
Willy Tarreaud2d33482019-04-25 17:09:07 +02002349profiling.tasks { auto | on | off }
2350 Enables ('on') or disables ('off') per-task CPU profiling. When set to 'auto'
2351 the profiling automatically turns on a thread when it starts to suffer from
2352 an average latency of 1000 microseconds or higher as reported in the
2353 "avg_loop_us" activity field, and automatically turns off when the latency
John Roeslerfb2fce12019-07-10 15:45:51 -05002354 returns below 990 microseconds (this value is an average over the last 1024
Willy Tarreaud2d33482019-04-25 17:09:07 +02002355 loops so it does not vary quickly and tends to significantly smooth short
2356 spikes). It may also spontaneously trigger from time to time on overloaded
2357 systems, containers, or virtual machines, or when the system swaps (which
2358 must absolutely never happen on a load balancer).
2359
2360 CPU profiling per task can be very convenient to report where the time is
2361 spent and which requests have what effect on which other request. Enabling
2362 it will typically affect the overall's performance by less than 1%, thus it
2363 is recommended to leave it to the default 'auto' value so that it only
2364 operates when a problem is identified. This feature requires a system
Willy Tarreau75c62c22018-11-22 11:02:09 +01002365 supporting the clock_gettime(2) syscall with clock identifiers
2366 CLOCK_MONOTONIC and CLOCK_THREAD_CPUTIME_ID, otherwise the reported time will
2367 be zero. This option may be changed at run time using "set profiling" on the
2368 CLI.
2369
Willy Tarreaufe255b72007-10-14 23:09:26 +02002370spread-checks <0..50, in percent>
Simon Hormand60d6912013-11-25 10:46:36 +09002371 Sometimes it is desirable to avoid sending agent and health checks to
2372 servers at exact intervals, for instance when many logical servers are
2373 located on the same physical server. With the help of this parameter, it
2374 becomes possible to add some randomness in the check interval between 0
2375 and +/- 50%. A value between 2 and 5 seems to show good results. The
2376 default value remains at 0.
Willy Tarreaufe255b72007-10-14 23:09:26 +02002377
Davor Ocelice9ed2812017-12-25 17:49:28 +01002378ssl-engine <name> [algo <comma-separated list of algorithms>]
Grant Zhang872f9c22017-01-21 01:10:18 +00002379 Sets the OpenSSL engine to <name>. List of valid values for <name> may be
Davor Ocelice9ed2812017-12-25 17:49:28 +01002380 obtained using the command "openssl engine". This statement may be used
Grant Zhang872f9c22017-01-21 01:10:18 +00002381 multiple times, it will simply enable multiple crypto engines. Referencing an
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002382 unsupported engine will prevent HAProxy from starting. Note that many engines
Grant Zhang872f9c22017-01-21 01:10:18 +00002383 will lead to lower HTTPS performance than pure software with recent
2384 processors. The optional command "algo" sets the default algorithms an ENGINE
2385 will supply using the OPENSSL function ENGINE_set_default_string(). A value
Davor Ocelice9ed2812017-12-25 17:49:28 +01002386 of "ALL" uses the engine for all cryptographic operations. If no list of
2387 algo is specified then the value of "ALL" is used. A comma-separated list
Grant Zhang872f9c22017-01-21 01:10:18 +00002388 of different algorithms may be specified, including: RSA, DSA, DH, EC, RAND,
2389 CIPHERS, DIGESTS, PKEY, PKEY_CRYPTO, PKEY_ASN1. This is the same format that
2390 openssl configuration file uses:
2391 https://www.openssl.org/docs/man1.0.2/apps/config.html
2392
Grant Zhangfa6c7ee2017-01-14 01:42:15 +00002393ssl-mode-async
2394 Adds SSL_MODE_ASYNC mode to the SSL context. This enables asynchronous TLS
Emeric Brun3854e012017-05-17 20:42:48 +02002395 I/O operations if asynchronous capable SSL engines are used. The current
Emeric Brunb5e42a82017-06-06 12:35:14 +00002396 implementation supports a maximum of 32 engines. The Openssl ASYNC API
2397 doesn't support moving read/write buffers and is not compliant with
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002398 HAProxy's buffer management. So the asynchronous mode is disabled on
John Roeslerfb2fce12019-07-10 15:45:51 -05002399 read/write operations (it is only enabled during initial and renegotiation
Emeric Brunb5e42a82017-06-06 12:35:14 +00002400 handshakes).
Grant Zhangfa6c7ee2017-01-14 01:42:15 +00002401
Willy Tarreau33cb0652014-12-23 22:52:37 +01002402tune.buffers.limit <number>
2403 Sets a hard limit on the number of buffers which may be allocated per process.
2404 The default value is zero which means unlimited. The minimum non-zero value
2405 will always be greater than "tune.buffers.reserve" and should ideally always
2406 be about twice as large. Forcing this value can be particularly useful to
2407 limit the amount of memory a process may take, while retaining a sane
Davor Ocelice9ed2812017-12-25 17:49:28 +01002408 behavior. When this limit is reached, sessions which need a buffer wait for
Willy Tarreau33cb0652014-12-23 22:52:37 +01002409 another one to be released by another session. Since buffers are dynamically
2410 allocated and released, the waiting time is very short and not perceptible
2411 provided that limits remain reasonable. In fact sometimes reducing the limit
2412 may even increase performance by increasing the CPU cache's efficiency. Tests
2413 have shown good results on average HTTP traffic with a limit to 1/10 of the
2414 expected global maxconn setting, which also significantly reduces memory
2415 usage. The memory savings come from the fact that a number of connections
2416 will not allocate 2*tune.bufsize. It is best not to touch this value unless
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002417 advised to do so by an HAProxy core developer.
Willy Tarreau33cb0652014-12-23 22:52:37 +01002418
Willy Tarreau1058ae72014-12-23 22:40:40 +01002419tune.buffers.reserve <number>
2420 Sets the number of buffers which are pre-allocated and reserved for use only
2421 during memory shortage conditions resulting in failed memory allocations. The
2422 minimum value is 2 and is also the default. There is no reason a user would
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002423 want to change this value, it's mostly aimed at HAProxy core developers.
Willy Tarreau1058ae72014-12-23 22:40:40 +01002424
Willy Tarreau27a674e2009-08-17 07:23:33 +02002425tune.bufsize <number>
2426 Sets the buffer size to this size (in bytes). Lower values allow more
2427 sessions to coexist in the same amount of RAM, and higher values allow some
2428 applications with very large cookies to work. The default value is 16384 and
2429 can be changed at build time. It is strongly recommended not to change this
2430 from the default value, as very low values will break some services such as
2431 statistics, and values larger than default size will increase memory usage,
2432 possibly causing the system to run out of memory. At least the global maxconn
Willy Tarreau45a66cc2017-11-24 11:28:00 +01002433 parameter should be decreased by the same factor as this one is increased. In
2434 addition, use of HTTP/2 mandates that this value must be 16384 or more. If an
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002435 HTTP request is larger than (tune.bufsize - tune.maxrewrite), HAProxy will
Dmitry Sivachenkof6f4f7b2012-10-21 18:10:25 +04002436 return HTTP 400 (Bad Request) error. Similarly if an HTTP response is larger
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002437 than this size, HAProxy will return HTTP 502 (Bad Gateway). Note that the
Willy Tarreauc77d3642018-12-12 06:19:42 +01002438 value set using this parameter will automatically be rounded up to the next
2439 multiple of 8 on 32-bit machines and 16 on 64-bit machines.
Willy Tarreau27a674e2009-08-17 07:23:33 +02002440
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +01002441tune.chksize <number> (deprecated)
2442 This option is deprecated and ignored.
Willy Tarreau43961d52010-10-04 20:39:20 +02002443
William Lallemandf3747832012-11-09 12:33:10 +01002444tune.comp.maxlevel <number>
2445 Sets the maximum compression level. The compression level affects CPU
2446 usage during compression. This value affects CPU usage during compression.
2447 Each session using compression initializes the compression algorithm with
2448 this value. The default value is 1.
2449
Willy Tarreauc299e1e2019-02-27 11:35:12 +01002450tune.fail-alloc
2451 If compiled with DEBUG_FAIL_ALLOC, gives the percentage of chances an
2452 allocation attempt fails. Must be between 0 (no failure) and 100 (no
2453 success). This is useful to debug and make sure memory failures are handled
2454 gracefully.
2455
Willy Tarreaubc52bec2020-06-18 08:58:47 +02002456tune.fd.edge-triggered { on | off } [ EXPERIMENTAL ]
2457 Enables ('on') or disables ('off') the edge-triggered polling mode for FDs
2458 that support it. This is currently only support with epoll. It may noticeably
2459 reduce the number of epoll_ctl() calls and slightly improve performance in
2460 certain scenarios. This is still experimental, it may result in frozen
2461 connections if bugs are still present, and is disabled by default.
2462
Willy Tarreaufe20e5b2017-07-27 11:42:14 +02002463tune.h2.header-table-size <number>
2464 Sets the HTTP/2 dynamic header table size. It defaults to 4096 bytes and
2465 cannot be larger than 65536 bytes. A larger value may help certain clients
2466 send more compact requests, depending on their capabilities. This amount of
2467 memory is consumed for each HTTP/2 connection. It is recommended not to
2468 change it.
2469
Willy Tarreaue6baec02017-07-27 11:45:11 +02002470tune.h2.initial-window-size <number>
2471 Sets the HTTP/2 initial window size, which is the number of bytes the client
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002472 can upload before waiting for an acknowledgment from HAProxy. This setting
Davor Ocelice9ed2812017-12-25 17:49:28 +01002473 only affects payload contents (i.e. the body of POST requests), not headers.
Willy Tarreaue6baec02017-07-27 11:45:11 +02002474 The default value is 65535, which roughly allows up to 5 Mbps of upload
2475 bandwidth per client over a network showing a 100 ms ping time, or 500 Mbps
2476 over a 1-ms local network. It can make sense to increase this value to allow
2477 faster uploads, or to reduce it to increase fairness when dealing with many
2478 clients. It doesn't affect resource usage.
2479
Willy Tarreau5242ef82017-07-27 11:47:28 +02002480tune.h2.max-concurrent-streams <number>
2481 Sets the HTTP/2 maximum number of concurrent streams per connection (ie the
2482 number of outstanding requests on a single connection). The default value is
2483 100. A larger one may slightly improve page load time for complex sites when
2484 visited over high latency networks, but increases the amount of resources a
2485 single client may allocate. A value of zero disables the limit so a single
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002486 client may create as many streams as allocatable by HAProxy. It is highly
Willy Tarreau5242ef82017-07-27 11:47:28 +02002487 recommended not to change this value.
2488
Willy Tarreaua24b35c2019-02-21 13:24:36 +01002489tune.h2.max-frame-size <number>
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002490 Sets the HTTP/2 maximum frame size that HAProxy announces it is willing to
Willy Tarreaua24b35c2019-02-21 13:24:36 +01002491 receive to its peers. The default value is the largest between 16384 and the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002492 buffer size (tune.bufsize). In any case, HAProxy will not announce support
Willy Tarreaua24b35c2019-02-21 13:24:36 +01002493 for frame sizes larger than buffers. The main purpose of this setting is to
2494 allow to limit the maximum frame size setting when using large buffers. Too
2495 large frame sizes might have performance impact or cause some peers to
2496 misbehave. It is highly recommended not to change this value.
2497
Willy Tarreau193b8c62012-11-22 00:17:38 +01002498tune.http.cookielen <number>
2499 Sets the maximum length of captured cookies. This is the maximum value that
2500 the "capture cookie xxx len yyy" will be allowed to take, and any upper value
2501 will automatically be truncated to this one. It is important not to set too
2502 high a value because all cookie captures still allocate this size whatever
2503 their configured value (they share a same pool). This value is per request
2504 per response, so the memory allocated is twice this value per connection.
2505 When not specified, the limit is set to 63 characters. It is recommended not
2506 to change this value.
2507
Stéphane Cottin23e9e932017-05-18 08:58:41 +02002508tune.http.logurilen <number>
Davor Ocelice9ed2812017-12-25 17:49:28 +01002509 Sets the maximum length of request URI in logs. This prevents truncating long
2510 request URIs with valuable query strings in log lines. This is not related
Stéphane Cottin23e9e932017-05-18 08:58:41 +02002511 to syslog limits. If you increase this limit, you may also increase the
Davor Ocelice9ed2812017-12-25 17:49:28 +01002512 'log ... len yyy' parameter. Your syslog daemon may also need specific
Stéphane Cottin23e9e932017-05-18 08:58:41 +02002513 configuration directives too.
2514 The default value is 1024.
2515
Willy Tarreauac1932d2011-10-24 19:14:41 +02002516tune.http.maxhdr <number>
2517 Sets the maximum number of headers in a request. When a request comes with a
2518 number of headers greater than this value (including the first line), it is
2519 rejected with a "400 Bad Request" status code. Similarly, too large responses
2520 are blocked with "502 Bad Gateway". The default value is 101, which is enough
2521 for all usages, considering that the widely deployed Apache server uses the
2522 same limit. It can be useful to push this limit further to temporarily allow
Christopher Faulet50174f32017-06-21 16:31:35 +02002523 a buggy application to work by the time it gets fixed. The accepted range is
2524 1..32767. Keep in mind that each new header consumes 32bits of memory for
2525 each session, so don't push this limit too high.
Willy Tarreauac1932d2011-10-24 19:14:41 +02002526
Willy Tarreau76cc6992020-07-01 18:49:24 +02002527tune.idle-pool.shared { on | off }
2528 Enables ('on') or disables ('off') sharing of idle connection pools between
2529 threads for a same server. The default is to share them between threads in
2530 order to minimize the number of persistent connections to a server, and to
2531 optimize the connection reuse rate. But to help with debugging or when
2532 suspecting a bug in HAProxy around connection reuse, it can be convenient to
2533 forcefully disable this idle pool sharing between multiple threads, and force
Willy Tarreau0784db82021-02-19 11:45:22 +01002534 this option to "off". The default is on. It is strongly recommended against
2535 disabling this option without setting a conservative value on "pool-low-conn"
2536 for all servers relying on connection reuse to achieve a high performance
2537 level, otherwise connections might be closed very often as the thread count
2538 increases.
Willy Tarreau76cc6992020-07-01 18:49:24 +02002539
Willy Tarreau7e312732014-02-12 16:35:14 +01002540tune.idletimer <timeout>
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002541 Sets the duration after which HAProxy will consider that an empty buffer is
Willy Tarreau7e312732014-02-12 16:35:14 +01002542 probably associated with an idle stream. This is used to optimally adjust
2543 some packet sizes while forwarding large and small data alternatively. The
2544 decision to use splice() or to send large buffers in SSL is modulated by this
2545 parameter. The value is in milliseconds between 0 and 65535. A value of zero
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002546 means that HAProxy will not try to detect idle streams. The default is 1000,
Davor Ocelice9ed2812017-12-25 17:49:28 +01002547 which seems to correctly detect end user pauses (e.g. read a page before
John Roeslerfb2fce12019-07-10 15:45:51 -05002548 clicking). There should be no reason for changing this value. Please check
Willy Tarreau7e312732014-02-12 16:35:14 +01002549 tune.ssl.maxrecord below.
2550
Willy Tarreau7ac908b2019-02-27 12:02:18 +01002551tune.listener.multi-queue { on | off }
2552 Enables ('on') or disables ('off') the listener's multi-queue accept which
2553 spreads the incoming traffic to all threads a "bind" line is allowed to run
2554 on instead of taking them for itself. This provides a smoother traffic
2555 distribution and scales much better, especially in environments where threads
2556 may be unevenly loaded due to external activity (network interrupts colliding
2557 with one thread for example). This option is enabled by default, but it may
2558 be forcefully disabled for troubleshooting or for situations where it is
2559 estimated that the operating system already provides a good enough
2560 distribution and connections are extremely short-lived.
2561
Thierry FOURNIER90da1912015-03-05 11:17:06 +01002562tune.lua.forced-yield <number>
2563 This directive forces the Lua engine to execute a yield each <number> of
Tim Düsterhus4896c442016-11-29 02:15:19 +01002564 instructions executed. This permits interrupting a long script and allows the
Thierry FOURNIER90da1912015-03-05 11:17:06 +01002565 HAProxy scheduler to process other tasks like accepting connections or
2566 forwarding traffic. The default value is 10000 instructions. If HAProxy often
Davor Ocelice9ed2812017-12-25 17:49:28 +01002567 executes some Lua code but more responsiveness is required, this value can be
Thierry FOURNIER90da1912015-03-05 11:17:06 +01002568 lowered. If the Lua code is quite long and its result is absolutely required
2569 to process the data, the <number> can be increased.
2570
Willy Tarreau32f61e22015-03-18 17:54:59 +01002571tune.lua.maxmem
2572 Sets the maximum amount of RAM in megabytes per process usable by Lua. By
2573 default it is zero which means unlimited. It is important to set a limit to
2574 ensure that a bug in a script will not result in the system running out of
2575 memory.
2576
Thierry FOURNIER90da1912015-03-05 11:17:06 +01002577tune.lua.session-timeout <timeout>
2578 This is the execution timeout for the Lua sessions. This is useful for
Thierry FOURNIER7dd784b2015-10-01 14:49:33 +02002579 preventing infinite loops or spending too much time in Lua. This timeout
2580 counts only the pure Lua runtime. If the Lua does a sleep, the sleep is
Davor Ocelice9ed2812017-12-25 17:49:28 +01002581 not taken in account. The default timeout is 4s.
Thierry FOURNIER90da1912015-03-05 11:17:06 +01002582
2583tune.lua.task-timeout <timeout>
2584 Purpose is the same as "tune.lua.session-timeout", but this timeout is
2585 dedicated to the tasks. By default, this timeout isn't set because a task may
2586 remain alive during of the lifetime of HAProxy. For example, a task used to
2587 check servers.
2588
Thierry FOURNIER7dd784b2015-10-01 14:49:33 +02002589tune.lua.service-timeout <timeout>
2590 This is the execution timeout for the Lua services. This is useful for
2591 preventing infinite loops or spending too much time in Lua. This timeout
2592 counts only the pure Lua runtime. If the Lua does a sleep, the sleep is
Davor Ocelice9ed2812017-12-25 17:49:28 +01002593 not taken in account. The default timeout is 4s.
Thierry FOURNIER7dd784b2015-10-01 14:49:33 +02002594
Willy Tarreaua0250ba2008-01-06 11:22:57 +01002595tune.maxaccept <number>
Willy Tarreau16a21472012-11-19 12:39:59 +01002596 Sets the maximum number of consecutive connections a process may accept in a
2597 row before switching to other work. In single process mode, higher numbers
Willy Tarreau66161322021-02-19 15:50:27 +01002598 used to give better performance at high connection rates, though this is not
2599 the case anymore with the multi-queue. This value applies individually to
2600 each listener, so that the number of processes a listener is bound to is
2601 taken into account. This value defaults to 4 which showed best results. If a
2602 significantly higher value was inherited from an ancient config, it might be
2603 worth removing it as it will both increase performance and lower response
2604 time. In multi-process mode, it is divided by twice the number of processes
2605 the listener is bound to. Setting this value to -1 completely disables the
2606 limitation. It should normally not be needed to tweak this value.
Willy Tarreaua0250ba2008-01-06 11:22:57 +01002607
2608tune.maxpollevents <number>
2609 Sets the maximum amount of events that can be processed at once in a call to
2610 the polling system. The default value is adapted to the operating system. It
2611 has been noticed that reducing it below 200 tends to slightly decrease
2612 latency at the expense of network bandwidth, and increasing it above 200
2613 tends to trade latency for slightly increased bandwidth.
2614
Willy Tarreau27a674e2009-08-17 07:23:33 +02002615tune.maxrewrite <number>
2616 Sets the reserved buffer space to this size in bytes. The reserved space is
2617 used for header rewriting or appending. The first reads on sockets will never
2618 fill more than bufsize-maxrewrite. Historically it has defaulted to half of
2619 bufsize, though that does not make much sense since there are rarely large
2620 numbers of headers to add. Setting it too high prevents processing of large
2621 requests or responses. Setting it too low prevents addition of new headers
2622 to already large requests or to POST requests. It is generally wise to set it
2623 to about 1024. It is automatically readjusted to half of bufsize if it is
2624 larger than that. This means you don't have to worry about it when changing
2625 bufsize.
2626
Willy Tarreauf3045d22015-04-29 16:24:50 +02002627tune.pattern.cache-size <number>
2628 Sets the size of the pattern lookup cache to <number> entries. This is an LRU
2629 cache which reminds previous lookups and their results. It is used by ACLs
2630 and maps on slow pattern lookups, namely the ones using the "sub", "reg",
2631 "dir", "dom", "end", "bin" match methods as well as the case-insensitive
2632 strings. It applies to pattern expressions which means that it will be able
2633 to memorize the result of a lookup among all the patterns specified on a
2634 configuration line (including all those loaded from files). It automatically
2635 invalidates entries which are updated using HTTP actions or on the CLI. The
2636 default cache size is set to 10000 entries, which limits its footprint to
Willy Tarreau403bfbb2019-10-23 06:59:31 +02002637 about 5 MB per process/thread on 32-bit systems and 8 MB per process/thread
2638 on 64-bit systems, as caches are thread/process local. There is a very low
Willy Tarreauf3045d22015-04-29 16:24:50 +02002639 risk of collision in this cache, which is in the order of the size of the
2640 cache divided by 2^64. Typically, at 10000 requests per second with the
2641 default cache size of 10000 entries, there's 1% chance that a brute force
2642 attack could cause a single collision after 60 years, or 0.1% after 6 years.
2643 This is considered much lower than the risk of a memory corruption caused by
2644 aging components. If this is not acceptable, the cache can be disabled by
2645 setting this parameter to 0.
2646
Willy Tarreaubd9a0a72011-10-23 21:14:29 +02002647tune.pipesize <number>
2648 Sets the kernel pipe buffer size to this size (in bytes). By default, pipes
2649 are the default size for the system. But sometimes when using TCP splicing,
2650 it can improve performance to increase pipe sizes, especially if it is
2651 suspected that pipes are not filled and that many calls to splice() are
2652 performed. This has an impact on the kernel's memory footprint, so this must
2653 not be changed if impacts are not understood.
2654
Olivier Houchard88698d92019-04-16 19:07:22 +02002655tune.pool-high-fd-ratio <number>
2656 This setting sets the max number of file descriptors (in percentage) used by
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002657 HAProxy globally against the maximum number of file descriptors HAProxy can
Olivier Houchard88698d92019-04-16 19:07:22 +02002658 use before we start killing idle connections when we can't reuse a connection
2659 and we have to create a new one. The default is 25 (one quarter of the file
2660 descriptor will mean that roughly half of the maximum front connections can
2661 keep an idle connection behind, anything beyond this probably doesn't make
John Roeslerfb2fce12019-07-10 15:45:51 -05002662 much sense in the general case when targeting connection reuse).
Olivier Houchard88698d92019-04-16 19:07:22 +02002663
Willy Tarreau83ca3052020-07-01 18:30:16 +02002664tune.pool-low-fd-ratio <number>
2665 This setting sets the max number of file descriptors (in percentage) used by
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002666 HAProxy globally against the maximum number of file descriptors HAProxy can
Willy Tarreau83ca3052020-07-01 18:30:16 +02002667 use before we stop putting connection into the idle pool for reuse. The
2668 default is 20.
2669
Willy Tarreaue803de22010-01-21 17:43:04 +01002670tune.rcvbuf.client <number>
2671tune.rcvbuf.server <number>
2672 Forces the kernel socket receive buffer size on the client or the server side
2673 to the specified value in bytes. This value applies to all TCP/HTTP frontends
2674 and backends. It should normally never be set, and the default size (0) lets
John Roeslerfb2fce12019-07-10 15:45:51 -05002675 the kernel auto-tune this value depending on the amount of available memory.
Davor Ocelice9ed2812017-12-25 17:49:28 +01002676 However it can sometimes help to set it to very low values (e.g. 4096) in
Willy Tarreaue803de22010-01-21 17:43:04 +01002677 order to save kernel memory by preventing it from buffering too large amounts
2678 of received data. Lower values will significantly increase CPU usage though.
2679
Willy Tarreaub22fc302015-12-14 12:04:35 +01002680tune.recv_enough <number>
Davor Ocelice9ed2812017-12-25 17:49:28 +01002681 HAProxy uses some hints to detect that a short read indicates the end of the
Willy Tarreaub22fc302015-12-14 12:04:35 +01002682 socket buffers. One of them is that a read returns more than <recv_enough>
2683 bytes, which defaults to 10136 (7 segments of 1448 each). This default value
2684 may be changed by this setting to better deal with workloads involving lots
2685 of short messages such as telnet or SSH sessions.
2686
Olivier Houchard1599b802018-05-24 18:59:04 +02002687tune.runqueue-depth <number>
John Roeslerfb2fce12019-07-10 15:45:51 -05002688 Sets the maximum amount of task that can be processed at once when running
Willy Tarreau060a7612021-03-10 11:06:26 +01002689 tasks. The default value depends on the number of threads but sits between 35
2690 and 280, which tend to show the highest request rates and lowest latencies.
2691 Increasing it may incur latency when dealing with I/Os, making it too small
2692 can incur extra overhead. Higher thread counts benefit from lower values.
2693 When experimenting with much larger values, it may be useful to also enable
2694 tune.sched.low-latency and possibly tune.fd.edge-triggered to limit the
2695 maximum latency to the lowest possible.
Willy Tarreaue7723bd2020-06-24 11:11:02 +02002696
2697tune.sched.low-latency { on | off }
2698 Enables ('on') or disables ('off') the low-latency task scheduler. By default
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002699 HAProxy processes tasks from several classes one class at a time as this is
Willy Tarreaue7723bd2020-06-24 11:11:02 +02002700 the most efficient. But when running with large values of tune.runqueue-depth
2701 this can have a measurable effect on request or connection latency. When this
2702 low-latency setting is enabled, tasks of lower priority classes will always
2703 be executed before other ones if they exist. This will permit to lower the
2704 maximum latency experienced by new requests or connections in the middle of
2705 massive traffic, at the expense of a higher impact on this large traffic.
2706 For regular usage it is better to leave this off. The default value is off.
Olivier Houchard1599b802018-05-24 18:59:04 +02002707
Willy Tarreaue803de22010-01-21 17:43:04 +01002708tune.sndbuf.client <number>
2709tune.sndbuf.server <number>
2710 Forces the kernel socket send buffer size on the client or the server side to
2711 the specified value in bytes. This value applies to all TCP/HTTP frontends
2712 and backends. It should normally never be set, and the default size (0) lets
John Roeslerfb2fce12019-07-10 15:45:51 -05002713 the kernel auto-tune this value depending on the amount of available memory.
Davor Ocelice9ed2812017-12-25 17:49:28 +01002714 However it can sometimes help to set it to very low values (e.g. 4096) in
Willy Tarreaue803de22010-01-21 17:43:04 +01002715 order to save kernel memory by preventing it from buffering too large amounts
2716 of received data. Lower values will significantly increase CPU usage though.
2717 Another use case is to prevent write timeouts with extremely slow clients due
2718 to the kernel waiting for a large part of the buffer to be read before
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002719 notifying HAProxy again.
Willy Tarreaue803de22010-01-21 17:43:04 +01002720
Willy Tarreau6ec58db2012-11-16 16:32:15 +01002721tune.ssl.cachesize <number>
Emeric Brunaf9619d2012-11-28 18:47:52 +01002722 Sets the size of the global SSL session cache, in a number of blocks. A block
William Dauchy9a4bbfe2021-02-12 15:58:46 +01002723 is large enough to contain an encoded session without peer certificate. An
2724 encoded session with peer certificate is stored in multiple blocks depending
2725 on the size of the peer certificate. A block uses approximately 200 bytes of
2726 memory (based on `sizeof(struct sh_ssl_sess_hdr) + SHSESS_BLOCK_MIN_SIZE`
2727 calculation used for `shctx_init` function). The default value may be forced
2728 at build time, otherwise defaults to 20000. When the cache is full, the most
2729 idle entries are purged and reassigned. Higher values reduce the occurrence
2730 of such a purge, hence the number of CPU-intensive SSL handshakes by ensuring
2731 that all users keep their session as long as possible. All entries are
2732 pre-allocated upon startup and are shared between all processes if "nbproc"
2733 is greater than 1. Setting this value to 0 disables the SSL session cache.
Willy Tarreau6ec58db2012-11-16 16:32:15 +01002734
Emeric Brun8dc60392014-05-09 13:52:00 +02002735tune.ssl.force-private-cache
Lukas Tribus27935782018-10-01 02:00:16 +02002736 This option disables SSL session cache sharing between all processes. It
Emeric Brun8dc60392014-05-09 13:52:00 +02002737 should normally not be used since it will force many renegotiations due to
2738 clients hitting a random process. But it may be required on some operating
2739 systems where none of the SSL cache synchronization method may be used. In
2740 this case, adding a first layer of hash-based load balancing before the SSL
2741 layer might limit the impact of the lack of session sharing.
2742
William Lallemand7d42ef52020-07-06 11:41:30 +02002743tune.ssl.keylog { on | off }
2744 This option activates the logging of the TLS keys. It should be used with
2745 care as it will consume more memory per SSL session and could decrease
2746 performances. This is disabled by default.
2747
2748 These sample fetches should be used to generate the SSLKEYLOGFILE that is
2749 required to decipher traffic with wireshark.
2750
2751 https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/Key_Log_Format
2752
2753 The SSLKEYLOG is a series of lines which are formatted this way:
2754
2755 <Label> <space> <ClientRandom> <space> <Secret>
2756
2757 The ClientRandom is provided by the %[ssl_fc_client_random,hex] sample
2758 fetch, the secret and the Label could be find in the array below. You need
2759 to generate a SSLKEYLOGFILE with all the labels in this array.
2760
2761 The following sample fetches are hexadecimal strings and does not need to be
2762 converted.
2763
2764 SSLKEYLOGFILE Label | Sample fetches for the Secrets
2765 --------------------------------|-----------------------------------------
2766 CLIENT_EARLY_TRAFFIC_SECRET | %[ssl_fc_client_early_traffic_secret]
2767 CLIENT_HANDSHAKE_TRAFFIC_SECRET | %[ssl_fc_client_handshake_traffic_secret]
2768 SERVER_HANDSHAKE_TRAFFIC_SECRET | %[ssl_fc_server_handshake_traffic_secret]
2769 CLIENT_TRAFFIC_SECRET_0 | %[ssl_fc_client_traffic_secret_0]
2770 SERVER_TRAFFIC_SECRET_0 | %[ssl_fc_server_traffic_secret_0]
William Lallemandd742b6c2020-07-07 10:14:56 +02002771 EXPORTER_SECRET | %[ssl_fc_exporter_secret]
2772 EARLY_EXPORTER_SECRET | %[ssl_fc_early_exporter_secret]
William Lallemand7d42ef52020-07-06 11:41:30 +02002773
2774 This is only available with OpenSSL 1.1.1, and useful with TLS1.3 session.
2775
2776 If you want to generate the content of a SSLKEYLOGFILE with TLS < 1.3, you
2777 only need this line:
2778
2779 "CLIENT_RANDOM %[ssl_fc_client_random,hex] %[ssl_fc_session_key,hex]"
2780
Emeric Brun4f65bff2012-11-16 15:11:00 +01002781tune.ssl.lifetime <timeout>
2782 Sets how long a cached SSL session may remain valid. This time is expressed
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03002783 in seconds and defaults to 300 (5 min). It is important to understand that it
Emeric Brun4f65bff2012-11-16 15:11:00 +01002784 does not guarantee that sessions will last that long, because if the cache is
2785 full, the longest idle sessions will be purged despite their configured
2786 lifetime. The real usefulness of this setting is to prevent sessions from
2787 being used for too long.
2788
Willy Tarreaubfd59462013-02-21 07:46:09 +01002789tune.ssl.maxrecord <number>
2790 Sets the maximum amount of bytes passed to SSL_write() at a time. Default
2791 value 0 means there is no limit. Over SSL/TLS, the client can decipher the
2792 data only once it has received a full record. With large records, it means
2793 that clients might have to download up to 16kB of data before starting to
2794 process them. Limiting the value can improve page load times on browsers
2795 located over high latency or low bandwidth networks. It is suggested to find
2796 optimal values which fit into 1 or 2 TCP segments (generally 1448 bytes over
2797 Ethernet with TCP timestamps enabled, or 1460 when timestamps are disabled),
2798 keeping in mind that SSL/TLS add some overhead. Typical values of 1419 and
2799 2859 gave good results during tests. Use "strace -e trace=write" to find the
Davor Ocelice9ed2812017-12-25 17:49:28 +01002800 best value. HAProxy will automatically switch to this setting after an idle
Willy Tarreau7e312732014-02-12 16:35:14 +01002801 stream has been detected (see tune.idletimer above).
Willy Tarreaubfd59462013-02-21 07:46:09 +01002802
Remi Gacognef46cd6e2014-06-12 14:58:40 +02002803tune.ssl.default-dh-param <number>
2804 Sets the maximum size of the Diffie-Hellman parameters used for generating
2805 the ephemeral/temporary Diffie-Hellman key in case of DHE key exchange. The
2806 final size will try to match the size of the server's RSA (or DSA) key (e.g,
2807 a 2048 bits temporary DH key for a 2048 bits RSA key), but will not exceed
Willy Tarreau3ba77d22020-05-08 09:31:18 +02002808 this maximum value. Default value if 2048. Only 1024 or higher values are
Remi Gacognef46cd6e2014-06-12 14:58:40 +02002809 allowed. Higher values will increase the CPU load, and values greater than
2810 1024 bits are not supported by Java 7 and earlier clients. This value is not
Remi Gacogne47783ef2015-05-29 15:53:22 +02002811 used if static Diffie-Hellman parameters are supplied either directly
2812 in the certificate file or by using the ssl-dh-param-file parameter.
Remi Gacognef46cd6e2014-06-12 14:58:40 +02002813
Christopher Faulet31af49d2015-06-09 17:29:50 +02002814tune.ssl.ssl-ctx-cache-size <number>
2815 Sets the size of the cache used to store generated certificates to <number>
2816 entries. This is a LRU cache. Because generating a SSL certificate
2817 dynamically is expensive, they are cached. The default cache size is set to
2818 1000 entries.
2819
Thierry FOURNIER5bf77322017-02-25 12:45:22 +01002820tune.ssl.capture-cipherlist-size <number>
2821 Sets the maximum size of the buffer used for capturing client-hello cipher
2822 list. If the value is 0 (default value) the capture is disabled, otherwise
2823 a buffer is allocated for each SSL/TLS connection.
2824
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02002825tune.vars.global-max-size <size>
Christopher Fauletff2613e2016-11-09 11:36:17 +01002826tune.vars.proc-max-size <size>
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02002827tune.vars.reqres-max-size <size>
2828tune.vars.sess-max-size <size>
2829tune.vars.txn-max-size <size>
Christopher Fauletff2613e2016-11-09 11:36:17 +01002830 These five tunes help to manage the maximum amount of memory used by the
2831 variables system. "global" limits the overall amount of memory available for
2832 all scopes. "proc" limits the memory for the process scope, "sess" limits the
2833 memory for the session scope, "txn" for the transaction scope, and "reqres"
2834 limits the memory for each request or response processing.
2835 Memory accounting is hierarchical, meaning more coarse grained limits include
2836 the finer grained ones: "proc" includes "sess", "sess" includes "txn", and
2837 "txn" includes "reqres".
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02002838
Daniel Schneller0b547052016-03-21 20:46:57 +01002839 For example, when "tune.vars.sess-max-size" is limited to 100,
2840 "tune.vars.txn-max-size" and "tune.vars.reqres-max-size" cannot exceed
2841 100 either. If we create a variable "txn.var" that contains 100 bytes,
2842 all available space is consumed.
2843 Notice that exceeding the limits at runtime will not result in an error
2844 message, but values might be cut off or corrupted. So make sure to accurately
2845 plan for the amount of space needed to store all your variables.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02002846
William Lallemanda509e4c2012-11-07 16:54:34 +01002847tune.zlib.memlevel <number>
2848 Sets the memLevel parameter in zlib initialization for each session. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03002849 defines how much memory should be allocated for the internal compression
William Lallemanda509e4c2012-11-07 16:54:34 +01002850 state. A value of 1 uses minimum memory but is slow and reduces compression
Davor Ocelice9ed2812017-12-25 17:49:28 +01002851 ratio, a value of 9 uses maximum memory for optimal speed. Can be a value
William Lallemanda509e4c2012-11-07 16:54:34 +01002852 between 1 and 9. The default value is 8.
2853
2854tune.zlib.windowsize <number>
2855 Sets the window size (the size of the history buffer) as a parameter of the
2856 zlib initialization for each session. Larger values of this parameter result
Davor Ocelice9ed2812017-12-25 17:49:28 +01002857 in better compression at the expense of memory usage. Can be a value between
2858 8 and 15. The default value is 15.
Willy Tarreau6a06a402007-07-15 20:15:28 +02002859
Willy Tarreauc57f0e22009-05-10 13:12:33 +020028603.3. Debugging
2861--------------
Willy Tarreau6a06a402007-07-15 20:15:28 +02002862
Willy Tarreau6a06a402007-07-15 20:15:28 +02002863quiet
2864 Do not display any message during startup. It is equivalent to the command-
2865 line argument "-q".
2866
Willy Tarreau3eb10b82020-04-15 16:42:39 +02002867zero-warning
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002868 When this option is set, HAProxy will refuse to start if any warning was
Willy Tarreau3eb10b82020-04-15 16:42:39 +02002869 emitted while processing the configuration. It is highly recommended to set
2870 this option on configurations that are not changed often, as it helps detect
2871 subtle mistakes and keep the configuration clean and forward-compatible. Note
2872 that "haproxy -c" will also report errors in such a case. This option is
2873 equivalent to command line argument "-dW".
2874
Emeric Brunf099e792010-09-27 12:05:28 +02002875
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +010028763.4. Userlists
2877--------------
2878It is possible to control access to frontend/backend/listen sections or to
2879http stats by allowing only authenticated and authorized users. To do this,
2880it is required to create at least one userlist and to define users.
2881
2882userlist <listname>
Cyril Bonté78caf842010-03-10 22:41:43 +01002883 Creates new userlist with name <listname>. Many independent userlists can be
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002884 used to store authentication & authorization data for independent customers.
2885
2886group <groupname> [users <user>,<user>,(...)]
Cyril Bonté78caf842010-03-10 22:41:43 +01002887 Adds group <groupname> to the current userlist. It is also possible to
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002888 attach users to this group by using a comma separated list of names
2889 proceeded by "users" keyword.
2890
Cyril Bontéf0c60612010-02-06 14:44:47 +01002891user <username> [password|insecure-password <password>]
2892 [groups <group>,<group>,(...)]
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002893 Adds user <username> to the current userlist. Both secure (encrypted) and
2894 insecure (unencrypted) passwords can be used. Encrypted passwords are
Daniel Schnellerd06f31c2017-11-06 16:51:04 +01002895 evaluated using the crypt(3) function, so depending on the system's
2896 capabilities, different algorithms are supported. For example, modern Glibc
2897 based Linux systems support MD5, SHA-256, SHA-512, and, of course, the
2898 classic DES-based method of encrypting passwords.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002899
Daniel Schnellerd06f31c2017-11-06 16:51:04 +01002900 Attention: Be aware that using encrypted passwords might cause significantly
2901 increased CPU usage, depending on the number of requests, and the algorithm
2902 used. For any of the hashed variants, the password for each request must
2903 be processed through the chosen algorithm, before it can be compared to the
2904 value specified in the config file. Most current algorithms are deliberately
2905 designed to be expensive to compute to achieve resistance against brute
2906 force attacks. They do not simply salt/hash the clear text password once,
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002907 but thousands of times. This can quickly become a major factor in HAProxy's
Daniel Schnellerd06f31c2017-11-06 16:51:04 +01002908 overall CPU consumption!
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002909
2910 Example:
Cyril Bontéf0c60612010-02-06 14:44:47 +01002911 userlist L1
2912 group G1 users tiger,scott
2913 group G2 users xdb,scott
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002914
Cyril Bontéf0c60612010-02-06 14:44:47 +01002915 user tiger password $6$k6y3o.eP$JlKBx9za9667qe4(...)xHSwRv6J.C0/D7cV91
2916 user scott insecure-password elgato
2917 user xdb insecure-password hello
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002918
Cyril Bontéf0c60612010-02-06 14:44:47 +01002919 userlist L2
2920 group G1
2921 group G2
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002922
Cyril Bontéf0c60612010-02-06 14:44:47 +01002923 user tiger password $6$k6y3o.eP$JlKBx(...)xHSwRv6J.C0/D7cV91 groups G1
2924 user scott insecure-password elgato groups G1,G2
2925 user xdb insecure-password hello groups G2
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01002926
2927 Please note that both lists are functionally identical.
Willy Tarreau6a06a402007-07-15 20:15:28 +02002928
Emeric Brunf099e792010-09-27 12:05:28 +02002929
29303.5. Peers
Cyril Bontédc4d9032012-04-08 21:57:39 +02002931----------
Emeric Brun94900952015-06-11 18:25:54 +02002932It is possible to propagate entries of any data-types in stick-tables between
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002933several HAProxy instances over TCP connections in a multi-master fashion. Each
Emeric Brun94900952015-06-11 18:25:54 +02002934instance pushes its local updates and insertions to remote peers. The pushed
2935values overwrite remote ones without aggregation. Interrupted exchanges are
2936automatically detected and recovered from the last known point.
2937In addition, during a soft restart, the old process connects to the new one
2938using such a TCP connection to push all its entries before the new process
2939tries to connect to other peers. That ensures very fast replication during a
2940reload, it typically takes a fraction of a second even for large tables.
2941Note that Server IDs are used to identify servers remotely, so it is important
2942that configurations look similar or at least that the same IDs are forced on
2943each server on all participants.
Emeric Brunf099e792010-09-27 12:05:28 +02002944
2945peers <peersect>
Jamie Gloudon801a0a32012-08-25 00:18:33 -04002946 Creates a new peer list with name <peersect>. It is an independent section,
Emeric Brunf099e792010-09-27 12:05:28 +02002947 which is referenced by one or more stick-tables.
2948
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01002949bind [<address>]:<port_range> [, ...] [param*]
2950 Defines the binding parameters of the local peer of this "peers" section.
2951 Such lines are not supported with "peer" line in the same "peers" section.
2952
Willy Tarreau77e4bd12015-05-01 20:02:17 +02002953disabled
2954 Disables a peers section. It disables both listening and any synchronization
2955 related to this section. This is provided to disable synchronization of stick
2956 tables without having to comment out all "peers" references.
2957
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01002958default-bind [param*]
2959 Defines the binding parameters for the local peer, excepted its address.
2960
2961default-server [param*]
2962 Change default options for a server in a "peers" section.
2963
2964 Arguments:
2965 <param*> is a list of parameters for this server. The "default-server"
2966 keyword accepts an important number of options and has a complete
2967 section dedicated to it. Please refer to section 5 for more
2968 details.
2969
2970
2971 See also: "server" and section 5 about server options
2972
Willy Tarreau77e4bd12015-05-01 20:02:17 +02002973enable
2974 This re-enables a disabled peers section which was previously disabled.
2975
Jan Wagner3e678602020-12-17 22:22:32 +01002976log <address> [len <length>] [format <format>] [sample <ranges>:<sample_size>]
Frédéric Lécailleb6f759b2019-11-05 09:57:45 +01002977 <facility> [<level> [<minlevel>]]
2978 "peers" sections support the same "log" keyword as for the proxies to
2979 log information about the "peers" listener. See "log" option for proxies for
2980 more details.
2981
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01002982peer <peername> <ip>:<port> [param*]
Emeric Brunf099e792010-09-27 12:05:28 +02002983 Defines a peer inside a peers section.
2984 If <peername> is set to the local peer name (by default hostname, or forced
Dragan Dosen13cd54c2020-06-18 18:24:05 +02002985 using "-L" command line option or "localpeer" global configuration setting),
Daniel Corbett9f0843f2021-05-08 10:50:37 -04002986 HAProxy will listen for incoming remote peer connection on <ip>:<port>.
Dragan Dosen13cd54c2020-06-18 18:24:05 +02002987 Otherwise, <ip>:<port> defines where to connect to in order to join the
2988 remote peer, and <peername> is used at the protocol level to identify and
2989 validate the remote peer on the server side.
Emeric Brunf099e792010-09-27 12:05:28 +02002990
2991 During a soft restart, local peer <ip>:<port> is used by the old instance to
2992 connect the new one and initiate a complete replication (teaching process).
2993
2994 It is strongly recommended to have the exact same peers declaration on all
Dragan Dosen13cd54c2020-06-18 18:24:05 +02002995 peers and to only rely on the "-L" command line argument or the "localpeer"
2996 global configuration setting to change the local peer name. This makes it
2997 easier to maintain coherent configuration files across all peers.
Emeric Brunf099e792010-09-27 12:05:28 +02002998
William Lallemandb2f07452015-05-12 14:27:13 +02002999 You may want to reference some environment variables in the address
3000 parameter, see section 2.3 about environment variables.
Willy Tarreaudad36a32013-03-11 01:20:04 +01003001
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01003002 Note: "peer" keyword may transparently be replaced by "server" keyword (see
3003 "server" keyword explanation below).
3004
3005server <peername> [<ip>:<port>] [param*]
Michael Prokop4438c602019-05-24 10:25:45 +02003006 As previously mentioned, "peer" keyword may be replaced by "server" keyword
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01003007 with a support for all "server" parameters found in 5.2 paragraph.
3008 If the underlying peer is local, <ip>:<port> parameters must not be present.
3009 These parameters must be provided on a "bind" line (see "bind" keyword
3010 of this "peers" section).
3011 Some of these parameters are irrelevant for "peers" sections.
3012
3013
Cyril Bontédc4d9032012-04-08 21:57:39 +02003014 Example:
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01003015 # The old way.
Emeric Brunf099e792010-09-27 12:05:28 +02003016 peers mypeers
Willy Tarreauf7b30a92010-12-06 22:59:17 +01003017 peer haproxy1 192.168.0.1:1024
3018 peer haproxy2 192.168.0.2:1024
3019 peer haproxy3 10.2.0.1:1024
Emeric Brunf099e792010-09-27 12:05:28 +02003020
3021 backend mybackend
3022 mode tcp
3023 balance roundrobin
3024 stick-table type ip size 20k peers mypeers
3025 stick on src
3026
Willy Tarreauf7b30a92010-12-06 22:59:17 +01003027 server srv1 192.168.0.30:80
3028 server srv2 192.168.0.31:80
Emeric Brunf099e792010-09-27 12:05:28 +02003029
Frédéric Lécaille2f167b32019-01-11 14:13:54 +01003030 Example:
3031 peers mypeers
3032 bind 127.0.0.11:10001 ssl crt mycerts/pem
3033 default-server ssl verify none
3034 server hostA 127.0.0.10:10000
3035 server hostB #local peer
Emeric Brunf099e792010-09-27 12:05:28 +02003036
Frédéric Lécaille4f5b77c2019-03-18 14:05:58 +01003037
3038table <tablename> type {ip | integer | string [len <length>] | binary [len <length>]}
3039 size <size> [expire <expire>] [nopurge] [store <data_type>]*
3040
3041 Configure a stickiness table for the current section. This line is parsed
3042 exactly the same way as the "stick-table" keyword in others section, except
John Roeslerfb2fce12019-07-10 15:45:51 -05003043 for the "peers" argument which is not required here and with an additional
Frédéric Lécaille4f5b77c2019-03-18 14:05:58 +01003044 mandatory first parameter to designate the stick-table. Contrary to others
3045 sections, there may be several "table" lines in "peers" sections (see also
3046 "stick-table" keyword).
3047
3048 Also be aware of the fact that "peers" sections have their own stick-table
3049 namespaces to avoid collisions between stick-table names identical in
3050 different "peers" section. This is internally handled prepending the "peers"
3051 sections names to the name of the stick-tables followed by a '/' character.
3052 If somewhere else in the configuration file you have to refer to such
3053 stick-tables declared in "peers" sections you must use the prefixed version
3054 of the stick-table name as follows:
3055
3056 peers mypeers
3057 peer A ...
3058 peer B ...
3059 table t1 ...
3060
3061 frontend fe1
3062 tcp-request content track-sc0 src table mypeers/t1
3063
3064 This is also this prefixed version of the stick-table names which must be
3065 used to refer to stick-tables through the CLI.
3066
3067 About "peers" protocol, as only "peers" belonging to the same section may
3068 communicate with each others, there is no need to do such a distinction.
3069 Several "peers" sections may declare stick-tables with the same name.
3070 This is shorter version of the stick-table name which is sent over the network.
3071 There is only a '/' character as prefix to avoid stick-table name collisions between
3072 stick-tables declared as backends and stick-table declared in "peers" sections
3073 as follows in this weird but supported configuration:
3074
3075 peers mypeers
3076 peer A ...
3077 peer B ...
3078 table t1 type string size 10m store gpc0
3079
3080 backend t1
3081 stick-table type string size 10m store gpc0 peers mypeers
3082
Daniel Corbett67a82712020-07-06 23:01:19 -04003083 Here "t1" table declared in "mypeers" section has "mypeers/t1" as global name.
Frédéric Lécaille4f5b77c2019-03-18 14:05:58 +01003084 "t1" table declared as a backend as "t1" as global name. But at peer protocol
3085 level the former table is named "/t1", the latter is again named "t1".
3086
Simon Horman51a1cf62015-02-03 13:00:44 +090030873.6. Mailers
3088------------
3089It is possible to send email alerts when the state of servers changes.
3090If configured email alerts are sent to each mailer that is configured
3091in a mailers section. Email is sent to mailers using SMTP.
3092
Pieter Baauw386a1272015-08-16 15:26:24 +02003093mailers <mailersect>
Simon Horman51a1cf62015-02-03 13:00:44 +09003094 Creates a new mailer list with the name <mailersect>. It is an
3095 independent section which is referenced by one or more proxies.
3096
3097mailer <mailername> <ip>:<port>
3098 Defines a mailer inside a mailers section.
3099
3100 Example:
3101 mailers mymailers
3102 mailer smtp1 192.168.0.1:587
3103 mailer smtp2 192.168.0.2:587
3104
3105 backend mybackend
3106 mode tcp
3107 balance roundrobin
3108
3109 email-alert mailers mymailers
3110 email-alert from test1@horms.org
3111 email-alert to test2@horms.org
3112
3113 server srv1 192.168.0.30:80
3114 server srv2 192.168.0.31:80
3115
Pieter Baauw235fcfc2016-02-13 15:33:40 +01003116timeout mail <time>
3117 Defines the time available for a mail/connection to be made and send to
3118 the mail-server. If not defined the default value is 10 seconds. To allow
3119 for at least two SYN-ACK packets to be send during initial TCP handshake it
3120 is advised to keep this value above 4 seconds.
3121
3122 Example:
3123 mailers mymailers
3124 timeout mail 20s
3125 mailer smtp1 192.168.0.1:587
Simon Horman51a1cf62015-02-03 13:00:44 +09003126
William Lallemandc9515522019-06-12 16:32:11 +020031273.7. Programs
3128-------------
3129In master-worker mode, it is possible to launch external binaries with the
3130master, these processes are called programs. These programs are launched and
3131managed the same way as the workers.
3132
3133During a reload of HAProxy, those processes are dealing with the same
3134sequence as a worker:
3135
3136 - the master is re-executed
3137 - the master sends a SIGUSR1 signal to the program
3138 - if "option start-on-reload" is not disabled, the master launches a new
3139 instance of the program
3140
3141During a stop, or restart, a SIGTERM is sent to the programs.
3142
3143program <name>
3144 This is a new program section, this section will create an instance <name>
3145 which is visible in "show proc" on the master CLI. (See "9.4. Master CLI" in
3146 the management guide).
3147
3148command <command> [arguments*]
3149 Define the command to start with optional arguments. The command is looked
3150 up in the current PATH if it does not include an absolute path. This is a
3151 mandatory option of the program section. Arguments containing spaces must
3152 be enclosed in quotes or double quotes or be prefixed by a backslash.
3153
Andrew Heberle97236962019-07-12 11:50:26 +08003154user <user name>
3155 Changes the executed command user ID to the <user name> from /etc/passwd.
3156 See also "group".
3157
3158group <group name>
3159 Changes the executed command group ID to the <group name> from /etc/group.
3160 See also "user".
3161
William Lallemandc9515522019-06-12 16:32:11 +02003162option start-on-reload
3163no option start-on-reload
3164 Start (or not) a new instance of the program upon a reload of the master.
3165 The default is to start a new instance. This option may only be used in a
3166 program section.
3167
3168
Christopher Faulet76edc0f2020-01-13 15:52:01 +010031693.8. HTTP-errors
3170----------------
3171
3172It is possible to globally declare several groups of HTTP errors, to be
3173imported afterwards in any proxy section. Same group may be referenced at
3174several places and can be fully or partially imported.
3175
3176http-errors <name>
3177 Create a new http-errors group with the name <name>. It is an independent
3178 section that may be referenced by one or more proxies using its name.
3179
3180errorfile <code> <file>
3181 Associate a file contents to an HTTP error code
3182
3183 Arguments :
3184 <code> is the HTTP status code. Currently, HAProxy is capable of
Christopher Faulet612f2ea2020-05-27 09:57:28 +02003185 generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
Christopher Faulete095f312020-12-07 11:22:24 +01003186 425, 429, 500, 501, 502, 503, and 504.
Christopher Faulet76edc0f2020-01-13 15:52:01 +01003187
3188 <file> designates a file containing the full HTTP response. It is
3189 recommended to follow the common practice of appending ".http" to
3190 the filename so that people do not confuse the response with HTML
3191 error pages, and to use absolute paths, since files are read
3192 before any chroot is performed.
3193
3194 Please referrers to "errorfile" keyword in section 4 for details.
3195
3196 Example:
3197 http-errors website-1
3198 errorfile 400 /etc/haproxy/errorfiles/site1/400.http
3199 errorfile 404 /etc/haproxy/errorfiles/site1/404.http
3200 errorfile 408 /dev/null # work around Chrome pre-connect bug
3201
3202 http-errors website-2
3203 errorfile 400 /etc/haproxy/errorfiles/site2/400.http
3204 errorfile 404 /etc/haproxy/errorfiles/site2/404.http
3205 errorfile 408 /dev/null # work around Chrome pre-connect bug
3206
Emeric Brun99c453d2020-05-25 15:01:04 +020032073.9. Rings
3208----------
3209
3210It is possible to globally declare ring-buffers, to be used as target for log
3211servers or traces.
3212
3213ring <ringname>
3214 Creates a new ring-buffer with name <ringname>.
3215
3216description <text>
Daniel Corbett67a82712020-07-06 23:01:19 -04003217 The description is an optional description string of the ring. It will
Emeric Brun99c453d2020-05-25 15:01:04 +02003218 appear on CLI. By default, <name> is reused to fill this field.
3219
3220format <format>
3221 Format used to store events into the ring buffer.
3222
3223 Arguments:
3224 <format> is the log format used when generating syslog messages. It may be
3225 one of the following :
3226
3227 iso A message containing only the ISO date, followed by the text.
3228 The PID, process name and system name are omitted. This is
3229 designed to be used with a local log server.
3230
Emeric Brun0237c4e2020-11-27 16:24:34 +01003231 local Analog to rfc3164 syslog message format except that hostname
3232 field is stripped. This is the default.
3233 Note: option "log-send-hostname" switches the default to
3234 rfc3164.
3235
Emeric Brun99c453d2020-05-25 15:01:04 +02003236 raw A message containing only the text. The level, PID, date, time,
3237 process name and system name are omitted. This is designed to be
3238 used in containers or during development, where the severity
3239 only depends on the file descriptor used (stdout/stderr). This
3240 is the default.
3241
Emeric Brun0237c4e2020-11-27 16:24:34 +01003242 rfc3164 The RFC3164 syslog message format.
Emeric Brun99c453d2020-05-25 15:01:04 +02003243 (https://tools.ietf.org/html/rfc3164)
3244
3245 rfc5424 The RFC5424 syslog message format.
3246 (https://tools.ietf.org/html/rfc5424)
3247
3248 short A message containing only a level between angle brackets such as
3249 '<3>', followed by the text. The PID, date, time, process name
3250 and system name are omitted. This is designed to be used with a
3251 local log server. This format is compatible with what the systemd
3252 logger consumes.
3253
Emeric Brun54648852020-07-06 15:54:06 +02003254 priority A message containing only a level plus syslog facility between angle
3255 brackets such as '<63>', followed by the text. The PID, date, time,
3256 process name and system name are omitted. This is designed to be used
3257 with a local log server.
3258
Emeric Brun99c453d2020-05-25 15:01:04 +02003259 timed A message containing only a level between angle brackets such as
3260 '<3>', followed by ISO date and by the text. The PID, process
3261 name and system name are omitted. This is designed to be
3262 used with a local log server.
3263
3264maxlen <length>
3265 The maximum length of an event message stored into the ring,
3266 including formatted header. If an event message is longer than
3267 <length>, it will be truncated to this length.
3268
Emeric Brun494c5052020-05-28 11:13:15 +02003269server <name> <address> [param*]
3270 Used to configure a syslog tcp server to forward messages from ring buffer.
3271 This supports for all "server" parameters found in 5.2 paragraph. Some of
3272 these parameters are irrelevant for "ring" sections. Important point: there
3273 is little reason to add more than one server to a ring, because all servers
3274 will receive the exact same copy of the ring contents, and as such the ring
3275 will progress at the speed of the slowest server. If one server does not
3276 respond, it will prevent old messages from being purged and may block new
3277 messages from being inserted into the ring. The proper way to send messages
3278 to multiple servers is to use one distinct ring per log server, not to
Emeric Brun97556472020-05-30 01:42:45 +02003279 attach multiple servers to the same ring. Note that specific server directive
3280 "log-proto" is used to set the protocol used to send messages.
Emeric Brun494c5052020-05-28 11:13:15 +02003281
Emeric Brun99c453d2020-05-25 15:01:04 +02003282size <size>
3283 This is the optional size in bytes for the ring-buffer. Default value is
3284 set to BUFSIZE.
3285
Emeric Brun494c5052020-05-28 11:13:15 +02003286timeout connect <timeout>
3287 Set the maximum time to wait for a connection attempt to a server to succeed.
3288
3289 Arguments :
3290 <timeout> is the timeout value specified in milliseconds by default, but
3291 can be in any other unit if the number is suffixed by the unit,
3292 as explained at the top of this document.
3293
3294timeout server <timeout>
3295 Set the maximum time for pending data staying into output buffer.
3296
3297 Arguments :
3298 <timeout> is the timeout value specified in milliseconds by default, but
3299 can be in any other unit if the number is suffixed by the unit,
3300 as explained at the top of this document.
3301
Emeric Brun99c453d2020-05-25 15:01:04 +02003302 Example:
3303 global
3304 log ring@myring local7
3305
3306 ring myring
3307 description "My local buffer"
3308 format rfc3164
3309 maxlen 1200
3310 size 32764
Emeric Brun494c5052020-05-28 11:13:15 +02003311 timeout connect 5s
3312 timeout server 10s
Emeric Brun97556472020-05-30 01:42:45 +02003313 server mysyslogsrv 127.0.0.1:6514 log-proto octet-count
Emeric Brun99c453d2020-05-25 15:01:04 +02003314
Emeric Brun12941c82020-07-07 14:19:42 +020033153.10. Log forwarding
3316-------------------
3317
3318It is possible to declare one or multiple log forwarding section,
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003319HAProxy will forward all received log messages to a log servers list.
Emeric Brun12941c82020-07-07 14:19:42 +02003320
3321log-forward <name>
3322 Creates a new log forwarder proxy identified as <name>.
3323
Emeric Bruncbb7bf72020-10-05 14:39:35 +02003324backlog <conns>
3325 Give hints to the system about the approximate listen backlog desired size
3326 on connections accept.
3327
3328bind <addr> [param*]
3329 Used to configure a stream log listener to receive messages to forward.
Emeric Brunda46c1c2020-10-08 08:39:02 +02003330 This supports the "bind" parameters found in 5.1 paragraph including
3331 those about ssl but some statements such as "alpn" may be irrelevant for
3332 syslog protocol over TCP.
3333 Those listeners support both "Octet Counting" and "Non-Transparent-Framing"
Emeric Bruncbb7bf72020-10-05 14:39:35 +02003334 modes as defined in rfc-6587.
3335
Willy Tarreau76aaa7f2020-09-16 15:07:22 +02003336dgram-bind <addr> [param*]
Emeric Bruncbb7bf72020-10-05 14:39:35 +02003337 Used to configure a datagram log listener to receive messages to forward.
3338 Addresses must be in IPv4 or IPv6 form,followed by a port. This supports
3339 for some of the "bind" parameters found in 5.1 paragraph among which
3340 "interface", "namespace" or "transparent", the other ones being
Willy Tarreau26ff5da2020-09-16 15:22:19 +02003341 silently ignored as irrelevant for UDP/syslog case.
Emeric Brun12941c82020-07-07 14:19:42 +02003342
3343log global
Jan Wagner3e678602020-12-17 22:22:32 +01003344log <address> [len <length>] [format <format>] [sample <ranges>:<sample_size>]
Emeric Brun12941c82020-07-07 14:19:42 +02003345 <facility> [<level> [<minlevel>]]
3346 Used to configure target log servers. See more details on proxies
3347 documentation.
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003348 If no format specified, HAProxy tries to keep the incoming log format.
Emeric Brun12941c82020-07-07 14:19:42 +02003349 Configured facility is ignored, except if incoming message does not
3350 present a facility but one is mandatory on the outgoing format.
3351 If there is no timestamp available in the input format, but the field
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003352 exists in output format, HAProxy will use the local date.
Emeric Brun12941c82020-07-07 14:19:42 +02003353
3354 Example:
3355 global
3356 log stderr format iso local7
3357
3358 ring myring
3359 description "My local buffer"
3360 format rfc5424
3361 maxlen 1200
3362 size 32764
3363 timeout connect 5s
3364 timeout server 10s
3365 # syslog tcp server
3366 server mysyslogsrv 127.0.0.1:514 log-proto octet-count
3367
3368 log-forward sylog-loadb
Emeric Bruncbb7bf72020-10-05 14:39:35 +02003369 dgram-bind 127.0.0.1:1514
3370 bind 127.0.0.1:1514
Emeric Brun12941c82020-07-07 14:19:42 +02003371 # all messages on stderr
3372 log global
3373 # all messages on local tcp syslog server
3374 log ring@myring local0
3375 # load balance messages on 4 udp syslog servers
3376 log 127.0.0.1:10001 sample 1:4 local0
3377 log 127.0.0.1:10002 sample 2:4 local0
3378 log 127.0.0.1:10003 sample 3:4 local0
3379 log 127.0.0.1:10004 sample 4:4 local0
Christopher Faulet76edc0f2020-01-13 15:52:01 +01003380
Emeric Bruncbb7bf72020-10-05 14:39:35 +02003381maxconn <conns>
3382 Fix the maximum number of concurrent connections on a log forwarder.
3383 10 is the default.
3384
3385timeout client <timeout>
3386 Set the maximum inactivity time on the client side.
3387
Willy Tarreauc57f0e22009-05-10 13:12:33 +020033884. Proxies
Willy Tarreau6a06a402007-07-15 20:15:28 +02003389----------
Willy Tarreau0ba27502007-12-24 16:55:16 +01003390
Willy Tarreau6a06a402007-07-15 20:15:28 +02003391Proxy configuration can be located in a set of sections :
Willy Tarreau7c0b4d82021-02-12 14:58:08 +01003392 - defaults [<name>] [ from <defaults_name> ]
3393 - frontend <name> [ from <defaults_name> ]
3394 - backend <name> [ from <defaults_name> ]
3395 - listen <name> [ from <defaults_name> ]
Willy Tarreau6a06a402007-07-15 20:15:28 +02003396
3397A "frontend" section describes a set of listening sockets accepting client
3398connections.
3399
3400A "backend" section describes a set of servers to which the proxy will connect
3401to forward incoming connections.
3402
3403A "listen" section defines a complete proxy with its frontend and backend
3404parts combined in one section. It is generally useful for TCP-only traffic.
3405
Willy Tarreau7c0b4d82021-02-12 14:58:08 +01003406A "defaults" section resets all settings to the documented ones and presets new
3407ones for use by subsequent sections. All of "frontend", "backend" and "listen"
3408sections always take their initial settings from a defaults section, by default
3409the latest one that appears before the newly created section. It is possible to
3410explicitly designate a specific "defaults" section to load the initial settings
3411from by indicating its name on the section line after the optional keyword
3412"from". While "defaults" section do not impose a name, this use is encouraged
3413for better readability. It is also the only way to designate a specific section
3414to use instead of the default previous one. Since "defaults" section names are
3415optional, by default a very permissive check is applied on their name and these
3416are even permitted to overlap. However if a "defaults" section is referenced by
3417any other section, its name must comply with the syntax imposed on all proxy
3418names, and this name must be unique among the defaults sections. Please note
3419that regardless of what is currently permitted, it is recommended to avoid
3420duplicate section names in general and to respect the same syntax as for proxy
3421names. This rule might be enforced in a future version.
3422
3423Note that it is even possible for a defaults section to take its initial
3424settings from another one, and as such, inherit settings across multiple levels
3425of defaults sections. This can be convenient to establish certain configuration
3426profiles to carry groups of default settings (e.g. TCP vs HTTP or short vs long
3427timeouts) but can quickly become confusing to follow.
3428
Willy Tarreau0ba27502007-12-24 16:55:16 +01003429All proxy names must be formed from upper and lower case letters, digits,
3430'-' (dash), '_' (underscore) , '.' (dot) and ':' (colon). ACL names are
3431case-sensitive, which means that "www" and "WWW" are two different proxies.
3432
3433Historically, all proxy names could overlap, it just caused troubles in the
3434logs. Since the introduction of content switching, it is mandatory that two
3435proxies with overlapping capabilities (frontend/backend) have different names.
3436However, it is still permitted that a frontend and a backend share the same
3437name, as this configuration seems to be commonly encountered.
3438
3439Right now, two major proxy modes are supported : "tcp", also known as layer 4,
3440and "http", also known as layer 7. In layer 4 mode, HAProxy simply forwards
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01003441bidirectional traffic between two sides. In layer 7 mode, HAProxy analyzes the
Willy Tarreau0ba27502007-12-24 16:55:16 +01003442protocol, and can interact with it by allowing, blocking, switching, adding,
3443modifying, or removing arbitrary contents in requests or responses, based on
3444arbitrary criteria.
3445
Willy Tarreau70dffda2014-01-30 03:07:23 +01003446In HTTP mode, the processing applied to requests and responses flowing over
3447a connection depends in the combination of the frontend's HTTP options and
Julien Pivotto21ad3152019-12-10 13:11:17 +01003448the backend's. HAProxy supports 3 connection modes :
Willy Tarreau70dffda2014-01-30 03:07:23 +01003449
3450 - KAL : keep alive ("option http-keep-alive") which is the default mode : all
3451 requests and responses are processed, and connections remain open but idle
3452 between responses and new requests.
3453
Willy Tarreau70dffda2014-01-30 03:07:23 +01003454 - SCL: server close ("option http-server-close") : the server-facing
3455 connection is closed after the end of the response is received, but the
3456 client-facing connection remains open.
3457
Christopher Faulet315b39c2018-09-21 16:26:19 +02003458 - CLO: close ("option httpclose"): the connection is closed after the end of
3459 the response and "Connection: close" appended in both directions.
Willy Tarreau70dffda2014-01-30 03:07:23 +01003460
3461The effective mode that will be applied to a connection passing through a
3462frontend and a backend can be determined by both proxy modes according to the
3463following matrix, but in short, the modes are symmetric, keep-alive is the
Christopher Faulet315b39c2018-09-21 16:26:19 +02003464weakest option and close is the strongest.
Willy Tarreau70dffda2014-01-30 03:07:23 +01003465
Christopher Faulet315b39c2018-09-21 16:26:19 +02003466 Backend mode
Willy Tarreau70dffda2014-01-30 03:07:23 +01003467
Christopher Faulet315b39c2018-09-21 16:26:19 +02003468 | KAL | SCL | CLO
3469 ----+-----+-----+----
3470 KAL | KAL | SCL | CLO
3471 ----+-----+-----+----
Christopher Faulet315b39c2018-09-21 16:26:19 +02003472 mode SCL | SCL | SCL | CLO
3473 ----+-----+-----+----
3474 CLO | CLO | CLO | CLO
Willy Tarreau70dffda2014-01-30 03:07:23 +01003475
Christopher Faulet4d37e532021-03-26 14:44:00 +01003476It is possible to chain a TCP frontend to an HTTP backend. It is pointless if
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003477only HTTP traffic is handled. But it may be used to handle several protocols
3478within the same frontend. In this case, the client's connection is first handled
Christopher Faulet4d37e532021-03-26 14:44:00 +01003479as a raw tcp connection before being upgraded to HTTP. Before the upgrade, the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003480content processings are performend on raw data. Once upgraded, data is parsed
Christopher Faulet4d37e532021-03-26 14:44:00 +01003481and stored using an internal representation called HTX and it is no longer
3482possible to rely on raw representation. There is no way to go back.
Willy Tarreau0ba27502007-12-24 16:55:16 +01003483
Christopher Faulet4d37e532021-03-26 14:44:00 +01003484There are two kind of upgrades, in-place upgrades and destructive upgrades. The
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003485first ones involves a TCP to HTTP/1 upgrade. In HTTP/1, the request
Christopher Faulet4d37e532021-03-26 14:44:00 +01003486processings are serialized, thus the applicative stream can be preserved. The
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003487second one involves a TCP to HTTP/2 upgrade. Because it is a multiplexed
Christopher Faulet4d37e532021-03-26 14:44:00 +01003488protocol, the applicative stream cannot be associated to any HTTP/2 stream and
3489is destroyed. New applicative streams are then created when HAProxy receives
3490new HTTP/2 streams at the lower level, in the H2 multiplexer. It is important
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003491to understand this difference because that drastically changes the way to
Christopher Faulet4d37e532021-03-26 14:44:00 +01003492process data. When an HTTP/1 upgrade is performed, the content processings
3493already performed on raw data are neither lost nor reexecuted while for an
3494HTTP/2 upgrade, applicative streams are distinct and all frontend rules are
3495evaluated systematically on each one. And as said, the first stream, the TCP
3496one, is destroyed, but only after the frontend rules were evaluated.
3497
3498There is another importnat point to understand when HTTP processings are
3499performed from a TCP proxy. While HAProxy is able to parse HTTP/1 in-fly from
3500tcp-request content rules, it is not possible for HTTP/2. Only the HTTP/2
3501preface can be parsed. This is a huge limitation regarding the HTTP content
3502analysis in TCP. Concretely it is only possible to know if received data are
3503HTTP. For instance, it is not possible to choose a backend based on the Host
3504header value while it is trivial in HTTP/1. Hopefully, there is a solution to
3505mitigate this drawback.
3506
Daniel Corbett9f0843f2021-05-08 10:50:37 -04003507There are two ways to perform an HTTP upgrade. The first one, the historical
Christopher Faulet4d37e532021-03-26 14:44:00 +01003508method, is to select an HTTP backend. The upgrade happens when the backend is
3509set. Thus, for in-place upgrades, only the backend configuration is considered
3510in the HTTP data processing. For destructive upgrades, the applicative stream
3511is destroyed, thus its processing is stopped. With this method, possibilities
3512to choose a backend with an HTTP/2 connection are really limited, as mentioned
3513above, and a bit useless because the stream is destroyed. The second method is
3514to upgrade during the tcp-request content rules evaluation, thanks to the
3515"switch-mode http" action. In this case, the upgrade is performed in the
3516frontend context and it is possible to define HTTP directives in this
3517frontend. For in-place upgrades, it offers all the power of the HTTP analysis
3518as soon as possible. It is not that far from an HTTP frontend. For destructive
3519upgrades, it does not change anything except it is useless to choose a backend
3520on limited information. It is of course the recommended method. Thus, testing
3521the request protocol from the tcp-request content rules to perform an HTTP
3522upgrade is enough. All the remaining HTTP manipulation may be moved to the
3523frontend http-request ruleset. But keep in mind that tcp-request content rules
3524remains evaluated on each streams, that can't be changed.
Willy Tarreau70dffda2014-01-30 03:07:23 +01003525
Willy Tarreauc57f0e22009-05-10 13:12:33 +020035264.1. Proxy keywords matrix
3527--------------------------
Willy Tarreau0ba27502007-12-24 16:55:16 +01003528
Willy Tarreauc57f0e22009-05-10 13:12:33 +02003529The following list of keywords is supported. Most of them may only be used in a
3530limited set of section types. Some of them are marked as "deprecated" because
3531they are inherited from an old syntax which may be confusing or functionally
3532limited, and there are new recommended keywords to replace them. Keywords
Davor Ocelice9ed2812017-12-25 17:49:28 +01003533marked with "(*)" can be optionally inverted using the "no" prefix, e.g. "no
Willy Tarreauc57f0e22009-05-10 13:12:33 +02003534option contstats". This makes sense when the option has been enabled by default
Willy Tarreau3842f002009-06-14 11:39:52 +02003535and must be disabled for a specific instance. Such options may also be prefixed
3536with "default" in order to restore default settings regardless of what has been
3537specified in a previous "defaults" section.
Willy Tarreau0ba27502007-12-24 16:55:16 +01003538
Willy Tarreau6a06a402007-07-15 20:15:28 +02003539
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003540 keyword defaults frontend listen backend
3541------------------------------------+----------+----------+---------+---------
3542acl - X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003543backlog X X X -
3544balance X - X X
3545bind - X X -
3546bind-process X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003547capture cookie - X X -
3548capture request header - X X -
3549capture response header - X X -
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09003550clitcpka-cnt X X X -
3551clitcpka-idle X X X -
3552clitcpka-intvl X X X -
William Lallemand82fe75c2012-10-23 10:25:10 +02003553compression X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003554cookie X - X X
Thierry FOURNIERa0a1b752015-05-26 17:44:32 +02003555declare capture - X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003556default-server X - X X
3557default_backend X X X -
3558description - X X X
3559disabled X X X X
3560dispatch - - X X
Simon Horman51a1cf62015-02-03 13:00:44 +09003561email-alert from X X X X
Simon Horman64e34162015-02-06 11:11:57 +09003562email-alert level X X X X
Simon Horman51a1cf62015-02-03 13:00:44 +09003563email-alert mailers X X X X
3564email-alert myhostname X X X X
3565email-alert to X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003566enabled X X X X
3567errorfile X X X X
Christopher Faulet76edc0f2020-01-13 15:52:01 +01003568errorfiles X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003569errorloc X X X X
3570errorloc302 X X X X
3571-- keyword -------------------------- defaults - frontend - listen -- backend -
3572errorloc303 X X X X
Cyril Bonté4288c5a2018-03-12 22:02:59 +01003573force-persist - - X X
Christopher Fauletc3fe5332016-04-07 15:30:10 +02003574filter - X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003575fullconn X - X X
3576grace X X X X
3577hash-type X - X X
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01003578http-after-response - X X X
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02003579http-check comment X - X X
Christopher Faulete5870d82020-04-15 11:32:03 +02003580http-check connect X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003581http-check disable-on-404 X - X X
Christopher Faulete5870d82020-04-15 11:32:03 +02003582http-check expect X - X X
Peter Gervai8912ae62020-06-11 18:26:36 +02003583http-check send X - X X
Willy Tarreau7ab6aff2010-10-12 06:30:16 +02003584http-check send-state X - X X
Christopher Faulete5870d82020-04-15 11:32:03 +02003585http-check set-var X - X X
3586http-check unset-var X - X X
Christopher Faulet3b967c12020-05-15 15:47:44 +02003587http-error X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003588http-request - X X X
Willy Tarreaue365c0b2013-06-11 16:06:12 +02003589http-response - X X X
Willy Tarreau30631952015-08-06 15:05:24 +02003590http-reuse X - X X
Baptiste Assmann2c42ef52013-10-09 21:57:02 +02003591http-send-name-header - - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003592id - X X X
Cyril Bonté4288c5a2018-03-12 22:02:59 +01003593ignore-persist - - X X
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02003594load-server-state-from-file X - X X
William Lallemand0f99e342011-10-12 17:50:54 +02003595log (*) X X X X
Willy Tarreaufb4e7ea2015-01-07 14:55:17 +01003596log-format X X X -
Dragan Dosen7ad31542015-09-28 17:16:47 +02003597log-format-sd X X X -
Willy Tarreau094af4e2015-01-07 15:03:42 +01003598log-tag X X X X
Willy Tarreauc35362a2014-04-25 13:58:37 +02003599max-keep-alive-queue X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003600maxconn X X X -
3601mode X X X X
3602monitor fail - X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003603monitor-uri X X X -
3604option abortonclose (*) X - X X
3605option accept-invalid-http-request (*) X X X -
3606option accept-invalid-http-response (*) X - X X
3607option allbackups (*) X - X X
3608option checkcache (*) X - X X
3609option clitcpka (*) X X X -
3610option contstats (*) X X X -
Christopher Faulet89aed322020-06-02 17:33:56 +02003611option disable-h2-upgrade (*) X X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003612option dontlog-normal (*) X X X -
3613option dontlognull (*) X X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003614-- keyword -------------------------- defaults - frontend - listen -- backend -
3615option forwardfor X X X X
Christopher Faulet98fbe952019-07-22 16:18:24 +02003616option h1-case-adjust-bogus-client (*) X X X -
3617option h1-case-adjust-bogus-server (*) X - X X
Willy Tarreau9fbe18e2015-05-01 22:42:08 +02003618option http-buffer-request (*) X X X X
Willy Tarreau82649f92015-05-01 22:40:51 +02003619option http-ignore-probes (*) X X X -
Willy Tarreau16bfb022010-01-16 19:48:41 +01003620option http-keep-alive (*) X X X X
Willy Tarreau96e31212011-05-30 18:10:30 +02003621option http-no-delay (*) X X X X
Christopher Faulet98db9762018-09-21 10:25:19 +02003622option http-pretend-keepalive (*) X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003623option http-server-close (*) X X X X
3624option http-use-proxy-header (*) X X X -
3625option httpchk X - X X
3626option httpclose (*) X X X X
Freddy Spierenburge88b7732019-03-25 14:35:17 +01003627option httplog X X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003628option http_proxy (*) X X X X
Jamie Gloudon801a0a32012-08-25 00:18:33 -04003629option independent-streams (*) X X X X
Gabor Lekenyb4c81e42010-09-29 18:17:05 +02003630option ldap-check X - X X
Simon Horman98637e52014-06-20 12:30:16 +09003631option external-check X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003632option log-health-checks (*) X - X X
3633option log-separate-errors (*) X X X -
3634option logasap (*) X X X -
3635option mysql-check X - X X
3636option nolinger (*) X X X X
3637option originalto X X X X
3638option persist (*) X - X X
Baptiste Assmann809e22a2015-10-12 20:22:55 +02003639option pgsql-check X - X X
3640option prefer-last-server (*) X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003641option redispatch (*) X - X X
Hervé COMMOWICKec032d62011-08-05 16:23:48 +02003642option redis-check X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003643option smtpchk X - X X
3644option socket-stats (*) X X X -
3645option splice-auto (*) X X X X
3646option splice-request (*) X X X X
3647option splice-response (*) X X X X
Christopher Fauletba7bc162016-11-07 21:07:38 +01003648option spop-check - - - X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003649option srvtcpka (*) X - X X
3650option ssl-hello-chk X - X X
3651-- keyword -------------------------- defaults - frontend - listen -- backend -
Willy Tarreaued179852013-12-16 01:07:00 +01003652option tcp-check X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003653option tcp-smart-accept (*) X X X -
3654option tcp-smart-connect (*) X - X X
3655option tcpka X X X X
3656option tcplog X X X X
3657option transparent (*) X - X X
Simon Horman98637e52014-06-20 12:30:16 +09003658external-check command X - X X
3659external-check path X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003660persist rdp-cookie X - X X
3661rate-limit sessions X X X -
3662redirect - X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003663-- keyword -------------------------- defaults - frontend - listen -- backend -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003664retries X - X X
Olivier Houcharda254a372019-04-05 15:30:12 +02003665retry-on X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003666server - - X X
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02003667server-state-file-name X - X X
Frédéric Lécaillecb4502e2017-04-20 13:36:25 +02003668server-template - - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003669source X - X X
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09003670srvtcpka-cnt X - X X
3671srvtcpka-idle X - X X
3672srvtcpka-intvl X - X X
Baptiste Assmann5a549212015-10-12 20:30:24 +02003673stats admin - X X X
3674stats auth X X X X
3675stats enable X X X X
3676stats hide-version X X X X
3677stats http-request - X X X
3678stats realm X X X X
3679stats refresh X X X X
3680stats scope X X X X
3681stats show-desc X X X X
3682stats show-legends X X X X
3683stats show-node X X X X
3684stats uri X X X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003685-- keyword -------------------------- defaults - frontend - listen -- backend -
3686stick match - - X X
3687stick on - - X X
3688stick store-request - - X X
Willy Tarreaud8dc99f2011-07-01 11:33:25 +02003689stick store-response - - X X
Adam Spiers68af3c12017-04-06 16:31:39 +01003690stick-table - X X X
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02003691tcp-check comment X - X X
Christopher Faulet404f9192020-04-09 23:13:54 +02003692tcp-check connect X - X X
3693tcp-check expect X - X X
3694tcp-check send X - X X
Christopher Fauletb50b3e62020-05-05 18:43:43 +02003695tcp-check send-lf X - X X
Christopher Faulet404f9192020-04-09 23:13:54 +02003696tcp-check send-binary X - X X
Christopher Fauletb50b3e62020-05-05 18:43:43 +02003697tcp-check send-binary-lf X - X X
Christopher Faulet404f9192020-04-09 23:13:54 +02003698tcp-check set-var X - X X
3699tcp-check unset-var X - X X
Willy Tarreaue9656522010-08-17 15:40:09 +02003700tcp-request connection - X X -
3701tcp-request content - X X X
Willy Tarreaua56235c2010-09-14 11:31:36 +02003702tcp-request inspect-delay - X X X
Willy Tarreau4f614292016-10-21 17:49:36 +02003703tcp-request session - X X -
Emeric Brun0a3b67f2010-09-24 15:34:53 +02003704tcp-response content - - X X
3705tcp-response inspect-delay - - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003706timeout check X - X X
3707timeout client X X X -
Willy Tarreau05cdd962014-05-10 14:30:07 +02003708timeout client-fin X X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003709timeout connect X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003710timeout http-keep-alive X X X X
3711timeout http-request X X X X
3712timeout queue X - X X
3713timeout server X - X X
Willy Tarreau05cdd962014-05-10 14:30:07 +02003714timeout server-fin X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003715timeout tarpit X X X X
Willy Tarreauce887fd2012-05-12 12:50:00 +02003716timeout tunnel X - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003717transparent (deprecated) X - X X
William Lallemanda73203e2012-03-12 12:48:57 +01003718unique-id-format X X X -
3719unique-id-header X X X -
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003720use_backend - X X -
Christopher Fauletb30b3102019-09-12 23:03:09 +02003721use-fcgi-app - - X X
Willy Tarreau4a5cade2012-04-05 21:09:48 +02003722use-server - - X X
Willy Tarreau5c6f7b32010-02-26 13:34:29 +01003723------------------------------------+----------+----------+---------+---------
3724 keyword defaults frontend listen backend
Willy Tarreau6a06a402007-07-15 20:15:28 +02003725
Willy Tarreau0ba27502007-12-24 16:55:16 +01003726
Willy Tarreauc57f0e22009-05-10 13:12:33 +020037274.2. Alphabetically sorted keywords reference
3728---------------------------------------------
Willy Tarreau0ba27502007-12-24 16:55:16 +01003729
3730This section provides a description of each keyword and its usage.
3731
3732
3733acl <aclname> <criterion> [flags] [operator] <value> ...
3734 Declare or complete an access list.
3735 May be used in sections : defaults | frontend | listen | backend
3736 no | yes | yes | yes
3737 Example:
3738 acl invalid_src src 0.0.0.0/7 224.0.0.0/3
3739 acl invalid_src src_port 0:1023
3740 acl local_dst hdr(host) -i localhost
3741
Willy Tarreauc57f0e22009-05-10 13:12:33 +02003742 See section 7 about ACL usage.
Willy Tarreau0ba27502007-12-24 16:55:16 +01003743
3744
Willy Tarreauc73ce2b2008-01-06 10:55:10 +01003745backlog <conns>
3746 Give hints to the system about the approximate listen backlog desired size
3747 May be used in sections : defaults | frontend | listen | backend
3748 yes | yes | yes | no
3749 Arguments :
3750 <conns> is the number of pending connections. Depending on the operating
3751 system, it may represent the number of already acknowledged
Cyril Bontédc4d9032012-04-08 21:57:39 +02003752 connections, of non-acknowledged ones, or both.
Willy Tarreauc73ce2b2008-01-06 10:55:10 +01003753
3754 In order to protect against SYN flood attacks, one solution is to increase
3755 the system's SYN backlog size. Depending on the system, sometimes it is just
3756 tunable via a system parameter, sometimes it is not adjustable at all, and
3757 sometimes the system relies on hints given by the application at the time of
3758 the listen() syscall. By default, HAProxy passes the frontend's maxconn value
3759 to the listen() syscall. On systems which can make use of this value, it can
3760 sometimes be useful to be able to specify a different value, hence this
3761 backlog parameter.
3762
3763 On Linux 2.4, the parameter is ignored by the system. On Linux 2.6, it is
3764 used as a hint and the system accepts up to the smallest greater power of
3765 two, and never more than some limits (usually 32768).
3766
3767 See also : "maxconn" and the target operating system's tuning guide.
3768
3769
Willy Tarreau0ba27502007-12-24 16:55:16 +01003770balance <algorithm> [ <arguments> ]
Willy Tarreau226071e2014-04-10 11:55:45 +02003771balance url_param <param> [check_post]
Willy Tarreau0ba27502007-12-24 16:55:16 +01003772 Define the load balancing algorithm to be used in a backend.
3773 May be used in sections : defaults | frontend | listen | backend
3774 yes | no | yes | yes
3775 Arguments :
3776 <algorithm> is the algorithm used to select a server when doing load
3777 balancing. This only applies when no persistence information
3778 is available, or when a connection is redispatched to another
3779 server. <algorithm> may be one of the following :
3780
3781 roundrobin Each server is used in turns, according to their weights.
3782 This is the smoothest and fairest algorithm when the server's
3783 processing time remains equally distributed. This algorithm
3784 is dynamic, which means that server weights may be adjusted
Willy Tarreau9757a382009-10-03 12:56:50 +02003785 on the fly for slow starts for instance. It is limited by
Godbacha34bdc02013-07-22 07:44:53 +08003786 design to 4095 active servers per backend. Note that in some
Willy Tarreau9757a382009-10-03 12:56:50 +02003787 large farms, when a server becomes up after having been down
3788 for a very short time, it may sometimes take a few hundreds
3789 requests for it to be re-integrated into the farm and start
3790 receiving traffic. This is normal, though very rare. It is
3791 indicated here in case you would have the chance to observe
3792 it, so that you don't worry.
3793
3794 static-rr Each server is used in turns, according to their weights.
3795 This algorithm is as similar to roundrobin except that it is
3796 static, which means that changing a server's weight on the
3797 fly will have no effect. On the other hand, it has no design
3798 limitation on the number of servers, and when a server goes
3799 up, it is always immediately reintroduced into the farm, once
3800 the full map is recomputed. It also uses slightly less CPU to
3801 run (around -1%).
Willy Tarreau0ba27502007-12-24 16:55:16 +01003802
Willy Tarreau2d2a7f82008-03-17 12:07:56 +01003803 leastconn The server with the lowest number of connections receives the
3804 connection. Round-robin is performed within groups of servers
3805 of the same load to ensure that all servers will be used. Use
3806 of this algorithm is recommended where very long sessions are
3807 expected, such as LDAP, SQL, TSE, etc... but is not very well
3808 suited for protocols using short sessions such as HTTP. This
3809 algorithm is dynamic, which means that server weights may be
Willy Tarreau8c855f62020-10-22 17:41:45 +02003810 adjusted on the fly for slow starts for instance. It will
3811 also consider the number of queued connections in addition to
3812 the established ones in order to minimize queuing.
Willy Tarreau2d2a7f82008-03-17 12:07:56 +01003813
Willy Tarreauf09c6602012-02-13 17:12:08 +01003814 first The first server with available connection slots receives the
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03003815 connection. The servers are chosen from the lowest numeric
Willy Tarreauf09c6602012-02-13 17:12:08 +01003816 identifier to the highest (see server parameter "id"), which
3817 defaults to the server's position in the farm. Once a server
Willy Tarreau64559c52012-04-07 09:08:45 +02003818 reaches its maxconn value, the next server is used. It does
Willy Tarreauf09c6602012-02-13 17:12:08 +01003819 not make sense to use this algorithm without setting maxconn.
3820 The purpose of this algorithm is to always use the smallest
3821 number of servers so that extra servers can be powered off
3822 during non-intensive hours. This algorithm ignores the server
3823 weight, and brings more benefit to long session such as RDP
Willy Tarreau64559c52012-04-07 09:08:45 +02003824 or IMAP than HTTP, though it can be useful there too. In
3825 order to use this algorithm efficiently, it is recommended
3826 that a cloud controller regularly checks server usage to turn
3827 them off when unused, and regularly checks backend queue to
3828 turn new servers on when the queue inflates. Alternatively,
3829 using "http-check send-state" may inform servers on the load.
Willy Tarreauf09c6602012-02-13 17:12:08 +01003830
Willy Tarreau0ba27502007-12-24 16:55:16 +01003831 source The source IP address is hashed and divided by the total
3832 weight of the running servers to designate which server will
3833 receive the request. This ensures that the same client IP
3834 address will always reach the same server as long as no
3835 server goes down or up. If the hash result changes due to the
3836 number of running servers changing, many clients will be
3837 directed to a different server. This algorithm is generally
3838 used in TCP mode where no cookie may be inserted. It may also
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01003839 be used on the Internet to provide a best-effort stickiness
Willy Tarreau0ba27502007-12-24 16:55:16 +01003840 to clients which refuse session cookies. This algorithm is
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02003841 static by default, which means that changing a server's
3842 weight on the fly will have no effect, but this can be
3843 changed using "hash-type".
Willy Tarreau0ba27502007-12-24 16:55:16 +01003844
Oskar Stolc8dc41842012-05-19 10:19:54 +01003845 uri This algorithm hashes either the left part of the URI (before
3846 the question mark) or the whole URI (if the "whole" parameter
3847 is present) and divides the hash value by the total weight of
3848 the running servers. The result designates which server will
3849 receive the request. This ensures that the same URI will
3850 always be directed to the same server as long as no server
3851 goes up or down. This is used with proxy caches and
3852 anti-virus proxies in order to maximize the cache hit rate.
3853 Note that this algorithm may only be used in an HTTP backend.
3854 This algorithm is static by default, which means that
3855 changing a server's weight on the fly will have no effect,
3856 but this can be changed using "hash-type".
Willy Tarreau0ba27502007-12-24 16:55:16 +01003857
Oskar Stolc8dc41842012-05-19 10:19:54 +01003858 This algorithm supports two optional parameters "len" and
Marek Majkowski9c30fc12008-04-27 23:25:55 +02003859 "depth", both followed by a positive integer number. These
3860 options may be helpful when it is needed to balance servers
3861 based on the beginning of the URI only. The "len" parameter
3862 indicates that the algorithm should only consider that many
3863 characters at the beginning of the URI to compute the hash.
3864 Note that having "len" set to 1 rarely makes sense since most
3865 URIs start with a leading "/".
3866
3867 The "depth" parameter indicates the maximum directory depth
3868 to be used to compute the hash. One level is counted for each
3869 slash in the request. If both parameters are specified, the
3870 evaluation stops when either is reached.
3871
Willy Tarreau57a37412020-09-23 08:56:29 +02003872 A "path-only" parameter indicates that the hashing key starts
3873 at the first '/' of the path. This can be used to ignore the
3874 authority part of absolute URIs, and to make sure that HTTP/1
3875 and HTTP/2 URIs will provide the same hash.
3876
Willy Tarreau0ba27502007-12-24 16:55:16 +01003877 url_param The URL parameter specified in argument will be looked up in
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003878 the query string of each HTTP GET request.
3879
3880 If the modifier "check_post" is used, then an HTTP POST
Cyril Bontédc4d9032012-04-08 21:57:39 +02003881 request entity will be searched for the parameter argument,
3882 when it is not found in a query string after a question mark
Willy Tarreau226071e2014-04-10 11:55:45 +02003883 ('?') in the URL. The message body will only start to be
3884 analyzed once either the advertised amount of data has been
3885 received or the request buffer is full. In the unlikely event
3886 that chunked encoding is used, only the first chunk is
Cyril Bontédc4d9032012-04-08 21:57:39 +02003887 scanned. Parameter values separated by a chunk boundary, may
Willy Tarreau226071e2014-04-10 11:55:45 +02003888 be randomly balanced if at all. This keyword used to support
3889 an optional <max_wait> parameter which is now ignored.
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003890
3891 If the parameter is found followed by an equal sign ('=') and
3892 a value, then the value is hashed and divided by the total
3893 weight of the running servers. The result designates which
3894 server will receive the request.
3895
3896 This is used to track user identifiers in requests and ensure
3897 that a same user ID will always be sent to the same server as
3898 long as no server goes up or down. If no value is found or if
3899 the parameter is not found, then a round robin algorithm is
3900 applied. Note that this algorithm may only be used in an HTTP
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02003901 backend. This algorithm is static by default, which means
3902 that changing a server's weight on the fly will have no
3903 effect, but this can be changed using "hash-type".
Willy Tarreau0ba27502007-12-24 16:55:16 +01003904
Cyril Bontédc4d9032012-04-08 21:57:39 +02003905 hdr(<name>) The HTTP header <name> will be looked up in each HTTP
3906 request. Just as with the equivalent ACL 'hdr()' function,
3907 the header name in parenthesis is not case sensitive. If the
3908 header is absent or if it does not contain any value, the
3909 roundrobin algorithm is applied instead.
Benoitaffb4812009-03-25 13:02:10 +01003910
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01003911 An optional 'use_domain_only' parameter is available, for
Benoitaffb4812009-03-25 13:02:10 +01003912 reducing the hash algorithm to the main domain part with some
3913 specific headers such as 'Host'. For instance, in the Host
3914 value "haproxy.1wt.eu", only "1wt" will be considered.
3915
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02003916 This algorithm is static by default, which means that
3917 changing a server's weight on the fly will have no effect,
3918 but this can be changed using "hash-type".
3919
Willy Tarreau21c741a2019-01-14 18:14:27 +01003920 random
3921 random(<draws>)
3922 A random number will be used as the key for the consistent
Willy Tarreau760e81d2018-05-03 07:20:40 +02003923 hashing function. This means that the servers' weights are
3924 respected, dynamic weight changes immediately take effect, as
3925 well as new server additions. Random load balancing can be
3926 useful with large farms or when servers are frequently added
Willy Tarreau21c741a2019-01-14 18:14:27 +01003927 or removed as it may avoid the hammering effect that could
3928 result from roundrobin or leastconn in this situation. The
3929 hash-balance-factor directive can be used to further improve
3930 fairness of the load balancing, especially in situations
3931 where servers show highly variable response times. When an
3932 argument <draws> is present, it must be an integer value one
3933 or greater, indicating the number of draws before selecting
3934 the least loaded of these servers. It was indeed demonstrated
3935 that picking the least loaded of two servers is enough to
3936 significantly improve the fairness of the algorithm, by
3937 always avoiding to pick the most loaded server within a farm
3938 and getting rid of any bias that could be induced by the
3939 unfair distribution of the consistent list. Higher values N
3940 will take away N-1 of the highest loaded servers at the
3941 expense of performance. With very high values, the algorithm
3942 will converge towards the leastconn's result but much slower.
3943 The default value is 2, which generally shows very good
3944 distribution and performance. This algorithm is also known as
3945 the Power of Two Random Choices and is described here :
3946 http://www.eecs.harvard.edu/~michaelm/postscripts/handbook2001.pdf
Willy Tarreau760e81d2018-05-03 07:20:40 +02003947
Emeric Brun736aa232009-06-30 17:56:00 +02003948 rdp-cookie
Hervé COMMOWICKa3eb39c2011-08-05 18:48:51 +02003949 rdp-cookie(<name>)
Emeric Brun736aa232009-06-30 17:56:00 +02003950 The RDP cookie <name> (or "mstshash" if omitted) will be
3951 looked up and hashed for each incoming TCP request. Just as
3952 with the equivalent ACL 'req_rdp_cookie()' function, the name
3953 is not case-sensitive. This mechanism is useful as a degraded
3954 persistence mode, as it makes it possible to always send the
3955 same user (or the same session ID) to the same server. If the
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01003956 cookie is not found, the normal roundrobin algorithm is
Emeric Brun736aa232009-06-30 17:56:00 +02003957 used instead.
3958
3959 Note that for this to work, the frontend must ensure that an
3960 RDP cookie is already present in the request buffer. For this
3961 you must use 'tcp-request content accept' rule combined with
3962 a 'req_rdp_cookie_cnt' ACL.
3963
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02003964 This algorithm is static by default, which means that
3965 changing a server's weight on the fly will have no effect,
3966 but this can be changed using "hash-type".
3967
Cyril Bontédc4d9032012-04-08 21:57:39 +02003968 See also the rdp_cookie pattern fetch function.
Simon Hormanab814e02011-06-24 14:50:20 +09003969
Willy Tarreau0ba27502007-12-24 16:55:16 +01003970 <arguments> is an optional list of arguments which may be needed by some
Marek Majkowski9c30fc12008-04-27 23:25:55 +02003971 algorithms. Right now, only "url_param" and "uri" support an
3972 optional argument.
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003973
Willy Tarreau3cd9af22009-03-15 14:06:41 +01003974 The load balancing algorithm of a backend is set to roundrobin when no other
3975 algorithm, mode nor option have been set. The algorithm may only be set once
3976 for each backend.
Willy Tarreau0ba27502007-12-24 16:55:16 +01003977
Lukas Tribus80512b12018-10-27 20:07:40 +02003978 With authentication schemes that require the same connection like NTLM, URI
John Roeslerfb2fce12019-07-10 15:45:51 -05003979 based algorithms must not be used, as they would cause subsequent requests
Lukas Tribus80512b12018-10-27 20:07:40 +02003980 to be routed to different backend servers, breaking the invalid assumptions
3981 NTLM relies on.
3982
Willy Tarreau0ba27502007-12-24 16:55:16 +01003983 Examples :
3984 balance roundrobin
3985 balance url_param userid
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003986 balance url_param session_id check_post 64
Benoitaffb4812009-03-25 13:02:10 +01003987 balance hdr(User-Agent)
3988 balance hdr(host)
3989 balance hdr(Host) use_domain_only
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003990
3991 Note: the following caveats and limitations on using the "check_post"
3992 extension with "url_param" must be considered :
3993
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01003994 - all POST requests are eligible for consideration, because there is no way
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003995 to determine if the parameters will be found in the body or entity which
3996 may contain binary data. Therefore another method may be required to
3997 restrict consideration of POST requests that have no URL parameters in
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02003998 the body. (see acl http_end)
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02003999
4000 - using a <max_wait> value larger than the request buffer size does not
4001 make sense and is useless. The buffer size is set at build time, and
4002 defaults to 16 kB.
4003
4004 - Content-Encoding is not supported, the parameter search will probably
4005 fail; and load balancing will fall back to Round Robin.
4006
4007 - Expect: 100-continue is not supported, load balancing will fall back to
4008 Round Robin.
4009
Lukas Tribus23953682017-04-28 13:24:30 +00004010 - Transfer-Encoding (RFC7230 3.3.1) is only supported in the first chunk.
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02004011 If the entire parameter value is not present in the first chunk, the
4012 selection of server is undefined (actually, defined by how little
4013 actually appeared in the first chunk).
4014
4015 - This feature does not support generation of a 100, 411 or 501 response.
4016
4017 - In some cases, requesting "check_post" MAY attempt to scan the entire
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01004018 contents of a message body. Scanning normally terminates when linear
matt.farnsworth@nokia.com1c2ab962008-04-14 20:47:37 +02004019 white space or control characters are found, indicating the end of what
4020 might be a URL parameter list. This is probably not a concern with SGML
4021 type message bodies.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004022
Willy Tarreau294d0f02015-08-10 19:40:12 +02004023 See also : "dispatch", "cookie", "transparent", "hash-type" and "http_proxy".
Willy Tarreau0ba27502007-12-24 16:55:16 +01004024
4025
Willy Tarreaub6205fd2012-09-24 12:27:33 +02004026bind [<address>]:<port_range> [, ...] [param*]
4027bind /<path> [, ...] [param*]
Willy Tarreau0ba27502007-12-24 16:55:16 +01004028 Define one or several listening addresses and/or ports in a frontend.
4029 May be used in sections : defaults | frontend | listen | backend
4030 no | yes | yes | no
4031 Arguments :
Willy Tarreaub1e52e82008-01-13 14:49:51 +01004032 <address> is optional and can be a host name, an IPv4 address, an IPv6
4033 address, or '*'. It designates the address the frontend will
4034 listen on. If unset, all IPv4 addresses of the system will be
4035 listened on. The same will apply for '*' or the system's
David du Colombier9c938da2011-03-17 10:40:27 +01004036 special address "0.0.0.0". The IPv6 equivalent is '::'.
Willy Tarreau24709282013-03-10 21:32:12 +01004037 Optionally, an address family prefix may be used before the
4038 address to force the family regardless of the address format,
4039 which can be useful to specify a path to a unix socket with
4040 no slash ('/'). Currently supported prefixes are :
4041 - 'ipv4@' -> address is always IPv4
4042 - 'ipv6@' -> address is always IPv6
Emeric Brun3835c0d2020-07-07 09:46:09 +02004043 - 'udp@' -> address is resolved as IPv4 or IPv6 and
Emeric Brun12941c82020-07-07 14:19:42 +02004044 protocol UDP is used. Currently those listeners are
4045 supported only in log-forward sections.
Emeric Brun3835c0d2020-07-07 09:46:09 +02004046 - 'udp4@' -> address is always IPv4 and protocol UDP
Emeric Brun12941c82020-07-07 14:19:42 +02004047 is used. Currently those listeners are supported
4048 only in log-forward sections.
Emeric Brun3835c0d2020-07-07 09:46:09 +02004049 - 'udp6@' -> address is always IPv6 and protocol UDP
Emeric Brun12941c82020-07-07 14:19:42 +02004050 is used. Currently those listeners are supported
4051 only in log-forward sections.
Willy Tarreau24709282013-03-10 21:32:12 +01004052 - 'unix@' -> address is a path to a local unix socket
Willy Tarreau70f72e02014-07-08 00:37:50 +02004053 - 'abns@' -> address is in abstract namespace (Linux only).
4054 Note: since abstract sockets are not "rebindable", they
4055 do not cope well with multi-process mode during
4056 soft-restart, so it is better to avoid them if
4057 nbproc is greater than 1. The effect is that if the
4058 new process fails to start, only one of the old ones
4059 will be able to rebind to the socket.
Willy Tarreau40aa0702013-03-10 23:51:38 +01004060 - 'fd@<n>' -> use file descriptor <n> inherited from the
4061 parent. The fd must be bound and may or may not already
4062 be listening.
William Lallemand2fe7dd02018-09-11 16:51:29 +02004063 - 'sockpair@<n>'-> like fd@ but you must use the fd of a
4064 connected unix socket or of a socketpair. The bind waits
4065 to receive a FD over the unix socket and uses it as if it
4066 was the FD of an accept(). Should be used carefully.
William Lallemandb2f07452015-05-12 14:27:13 +02004067 You may want to reference some environment variables in the
4068 address parameter, see section 2.3 about environment
4069 variables.
Willy Tarreaub1e52e82008-01-13 14:49:51 +01004070
Willy Tarreauc5011ca2010-03-22 11:53:56 +01004071 <port_range> is either a unique TCP port, or a port range for which the
4072 proxy will accept connections for the IP address specified
Willy Tarreauceb24bc2010-11-09 12:46:41 +01004073 above. The port is mandatory for TCP listeners. Note that in
4074 the case of an IPv6 address, the port is always the number
4075 after the last colon (':'). A range can either be :
Willy Tarreauc5011ca2010-03-22 11:53:56 +01004076 - a numerical port (ex: '80')
4077 - a dash-delimited ports range explicitly stating the lower
4078 and upper bounds (ex: '2000-2100') which are included in
4079 the range.
4080
4081 Particular care must be taken against port ranges, because
4082 every <address:port> couple consumes one socket (= a file
4083 descriptor), so it's easy to consume lots of descriptors
4084 with a simple range, and to run out of sockets. Also, each
4085 <address:port> couple must be used only once among all
4086 instances running on a same system. Please note that binding
4087 to ports lower than 1024 generally require particular
Jamie Gloudon801a0a32012-08-25 00:18:33 -04004088 privileges to start the program, which are independent of
Willy Tarreauc5011ca2010-03-22 11:53:56 +01004089 the 'uid' parameter.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004090
Willy Tarreauceb24bc2010-11-09 12:46:41 +01004091 <path> is a UNIX socket path beginning with a slash ('/'). This is
Davor Ocelice9ed2812017-12-25 17:49:28 +01004092 alternative to the TCP listening port. HAProxy will then
Willy Tarreauceb24bc2010-11-09 12:46:41 +01004093 receive UNIX connections on the socket located at this place.
4094 The path must begin with a slash and by default is absolute.
4095 It can be relative to the prefix defined by "unix-bind" in
4096 the global section. Note that the total length of the prefix
4097 followed by the socket path cannot exceed some system limits
4098 for UNIX sockets, which commonly are set to 107 characters.
4099
Willy Tarreaub6205fd2012-09-24 12:27:33 +02004100 <param*> is a list of parameters common to all sockets declared on the
4101 same line. These numerous parameters depend on OS and build
4102 options and have a complete section dedicated to them. Please
4103 refer to section 5 to for more details.
Willy Tarreaua0ee1d02012-09-10 09:01:23 +02004104
Willy Tarreau0ba27502007-12-24 16:55:16 +01004105 It is possible to specify a list of address:port combinations delimited by
4106 commas. The frontend will then listen on all of these addresses. There is no
4107 fixed limit to the number of addresses and ports which can be listened on in
4108 a frontend, as well as there is no limit to the number of "bind" statements
4109 in a frontend.
4110
4111 Example :
4112 listen http_proxy
4113 bind :80,:443
4114 bind 10.0.0.1:10080,10.0.0.1:10443
Willy Tarreauceb24bc2010-11-09 12:46:41 +01004115 bind /var/run/ssl-frontend.sock user root mode 600 accept-proxy
Willy Tarreau0ba27502007-12-24 16:55:16 +01004116
Willy Tarreaua0ee1d02012-09-10 09:01:23 +02004117 listen http_https_proxy
4118 bind :80
Cyril Bonté0d44fc62012-10-09 22:45:33 +02004119 bind :443 ssl crt /etc/haproxy/site.pem
Willy Tarreaua0ee1d02012-09-10 09:01:23 +02004120
Willy Tarreau24709282013-03-10 21:32:12 +01004121 listen http_https_proxy_explicit
4122 bind ipv6@:80
4123 bind ipv4@public_ssl:443 ssl crt /etc/haproxy/site.pem
4124 bind unix@ssl-frontend.sock user root mode 600 accept-proxy
4125
Willy Tarreaudad36a32013-03-11 01:20:04 +01004126 listen external_bind_app1
William Lallemandb2f07452015-05-12 14:27:13 +02004127 bind "fd@${FD_APP1}"
Willy Tarreaudad36a32013-03-11 01:20:04 +01004128
Willy Tarreau55dcaf62015-09-27 15:03:15 +02004129 Note: regarding Linux's abstract namespace sockets, HAProxy uses the whole
4130 sun_path length is used for the address length. Some other programs
4131 such as socat use the string length only by default. Pass the option
4132 ",unix-tightsocklen=0" to any abstract socket definition in socat to
4133 make it compatible with HAProxy's.
4134
Willy Tarreauceb24bc2010-11-09 12:46:41 +01004135 See also : "source", "option forwardfor", "unix-bind" and the PROXY protocol
Willy Tarreaub6205fd2012-09-24 12:27:33 +02004136 documentation, and section 5 about bind options.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004137
4138
Christopher Fauletff4121f2017-11-22 16:38:49 +01004139bind-process [ all | odd | even | <process_num>[-[<process_num>]] ] ...
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004140 Limit visibility of an instance to a certain set of processes numbers.
4141 May be used in sections : defaults | frontend | listen | backend
4142 yes | yes | yes | yes
4143 Arguments :
4144 all All process will see this instance. This is the default. It
4145 may be used to override a default value.
4146
Willy Tarreaua9db57e2013-01-18 11:29:29 +01004147 odd This instance will be enabled on processes 1,3,5,...63. This
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004148 option may be combined with other numbers.
4149
Willy Tarreaua9db57e2013-01-18 11:29:29 +01004150 even This instance will be enabled on processes 2,4,6,...64. This
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004151 option may be combined with other numbers. Do not use it
4152 with less than 2 processes otherwise some instances might be
4153 missing from all processes.
4154
Christopher Fauletff4121f2017-11-22 16:38:49 +01004155 process_num The instance will be enabled on this process number or range,
Willy Tarreaua9db57e2013-01-18 11:29:29 +01004156 whose values must all be between 1 and 32 or 64 depending on
Christopher Fauletff4121f2017-11-22 16:38:49 +01004157 the machine's word size. Ranges can be partially defined. The
4158 higher bound can be omitted. In such case, it is replaced by
4159 the corresponding maximum value. If a proxy is bound to
4160 process numbers greater than the configured global.nbproc, it
4161 will either be forced to process #1 if a single process was
Willy Tarreau102df612014-05-07 23:56:38 +02004162 specified, or to all processes otherwise.
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004163
4164 This keyword limits binding of certain instances to certain processes. This
4165 is useful in order not to have too many processes listening to the same
4166 ports. For instance, on a dual-core machine, it might make sense to set
4167 'nbproc 2' in the global section, then distributes the listeners among 'odd'
4168 and 'even' instances.
4169
Willy Tarreaua9db57e2013-01-18 11:29:29 +01004170 At the moment, it is not possible to reference more than 32 or 64 processes
4171 using this keyword, but this should be more than enough for most setups.
4172 Please note that 'all' really means all processes regardless of the machine's
4173 word size, and is not limited to the first 32 or 64.
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004174
Willy Tarreau6ae1ba62014-05-07 19:01:58 +02004175 Each "bind" line may further be limited to a subset of the proxy's processes,
4176 please consult the "process" bind keyword in section 5.1.
4177
Willy Tarreaub369a042014-09-16 13:21:03 +02004178 When a frontend has no explicit "bind-process" line, it tries to bind to all
4179 the processes referenced by its "bind" lines. That means that frontends can
4180 easily adapt to their listeners' processes.
4181
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004182 If some backends are referenced by frontends bound to other processes, the
4183 backend automatically inherits the frontend's processes.
4184
4185 Example :
4186 listen app_ip1
4187 bind 10.0.0.1:80
Willy Tarreaubfcd3112010-10-23 11:22:08 +02004188 bind-process odd
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004189
4190 listen app_ip2
4191 bind 10.0.0.2:80
Willy Tarreaubfcd3112010-10-23 11:22:08 +02004192 bind-process even
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004193
4194 listen management
4195 bind 10.0.0.3:80
Willy Tarreaubfcd3112010-10-23 11:22:08 +02004196 bind-process 1 2 3 4
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004197
Willy Tarreau110ecc12012-11-15 17:50:01 +01004198 listen management
4199 bind 10.0.0.4:80
4200 bind-process 1-4
4201
Willy Tarreau6ae1ba62014-05-07 19:01:58 +02004202 See also : "nbproc" in global section, and "process" in section 5.1.
Willy Tarreau0b9c02c2009-02-04 22:05:05 +01004203
4204
Willy Tarreau0ba27502007-12-24 16:55:16 +01004205capture cookie <name> len <length>
4206 Capture and log a cookie in the request and in the response.
4207 May be used in sections : defaults | frontend | listen | backend
4208 no | yes | yes | no
4209 Arguments :
4210 <name> is the beginning of the name of the cookie to capture. In order
4211 to match the exact name, simply suffix the name with an equal
4212 sign ('='). The full name will appear in the logs, which is
4213 useful with application servers which adjust both the cookie name
Davor Ocelice9ed2812017-12-25 17:49:28 +01004214 and value (e.g. ASPSESSIONXXX).
Willy Tarreau0ba27502007-12-24 16:55:16 +01004215
4216 <length> is the maximum number of characters to report in the logs, which
4217 include the cookie name, the equal sign and the value, all in the
4218 standard "name=value" form. The string will be truncated on the
4219 right if it exceeds <length>.
4220
4221 Only the first cookie is captured. Both the "cookie" request headers and the
4222 "set-cookie" response headers are monitored. This is particularly useful to
4223 check for application bugs causing session crossing or stealing between
4224 users, because generally the user's cookies can only change on a login page.
4225
4226 When the cookie was not presented by the client, the associated log column
4227 will report "-". When a request does not cause a cookie to be assigned by the
4228 server, a "-" is reported in the response column.
4229
4230 The capture is performed in the frontend only because it is necessary that
4231 the log format does not change for a given frontend depending on the
4232 backends. This may change in the future. Note that there can be only one
Willy Tarreau193b8c62012-11-22 00:17:38 +01004233 "capture cookie" statement in a frontend. The maximum capture length is set
4234 by the global "tune.http.cookielen" setting and defaults to 63 characters. It
4235 is not possible to specify a capture in a "defaults" section.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004236
4237 Example:
4238 capture cookie ASPSESSION len 32
4239
4240 See also : "capture request header", "capture response header" as well as
Willy Tarreauc57f0e22009-05-10 13:12:33 +02004241 section 8 about logging.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004242
4243
4244capture request header <name> len <length>
Willy Tarreau4460d032012-11-21 23:37:37 +01004245 Capture and log the last occurrence of the specified request header.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004246 May be used in sections : defaults | frontend | listen | backend
4247 no | yes | yes | no
4248 Arguments :
4249 <name> is the name of the header to capture. The header names are not
Willy Tarreaud2a4aa22008-01-31 15:28:22 +01004250 case-sensitive, but it is a common practice to write them as they
Willy Tarreau0ba27502007-12-24 16:55:16 +01004251 appear in the requests, with the first letter of each word in
4252 upper case. The header name will not appear in the logs, only the
4253 value is reported, but the position in the logs is respected.
4254
4255 <length> is the maximum number of characters to extract from the value and
4256 report in the logs. The string will be truncated on the right if
4257 it exceeds <length>.
4258
Willy Tarreau4460d032012-11-21 23:37:37 +01004259 The complete value of the last occurrence of the header is captured. The
Willy Tarreau0ba27502007-12-24 16:55:16 +01004260 value will be added to the logs between braces ('{}'). If multiple headers
4261 are captured, they will be delimited by a vertical bar ('|') and will appear
Willy Tarreaucc6c8912009-02-22 10:53:55 +01004262 in the same order they were declared in the configuration. Non-existent
4263 headers will be logged just as an empty string. Common uses for request
4264 header captures include the "Host" field in virtual hosting environments, the
4265 "Content-length" when uploads are supported, "User-agent" to quickly
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01004266 differentiate between real users and robots, and "X-Forwarded-For" in proxied
Willy Tarreaucc6c8912009-02-22 10:53:55 +01004267 environments to find where the request came from.
4268
4269 Note that when capturing headers such as "User-agent", some spaces may be
4270 logged, making the log analysis more difficult. Thus be careful about what
4271 you log if you know your log parser is not smart enough to rely on the
4272 braces.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004273
Willy Tarreau0900abb2012-11-22 00:21:46 +01004274 There is no limit to the number of captured request headers nor to their
4275 length, though it is wise to keep them low to limit memory usage per session.
4276 In order to keep log format consistent for a same frontend, header captures
4277 can only be declared in a frontend. It is not possible to specify a capture
4278 in a "defaults" section.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004279
4280 Example:
4281 capture request header Host len 15
4282 capture request header X-Forwarded-For len 15
Cyril Bontéd1b0f7c2015-10-26 22:37:39 +01004283 capture request header Referer len 15
Willy Tarreau0ba27502007-12-24 16:55:16 +01004284
Willy Tarreauc57f0e22009-05-10 13:12:33 +02004285 See also : "capture cookie", "capture response header" as well as section 8
Willy Tarreau0ba27502007-12-24 16:55:16 +01004286 about logging.
4287
4288
4289capture response header <name> len <length>
Willy Tarreau4460d032012-11-21 23:37:37 +01004290 Capture and log the last occurrence of the specified response header.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004291 May be used in sections : defaults | frontend | listen | backend
4292 no | yes | yes | no
4293 Arguments :
4294 <name> is the name of the header to capture. The header names are not
Willy Tarreaud2a4aa22008-01-31 15:28:22 +01004295 case-sensitive, but it is a common practice to write them as they
Willy Tarreau0ba27502007-12-24 16:55:16 +01004296 appear in the response, with the first letter of each word in
4297 upper case. The header name will not appear in the logs, only the
4298 value is reported, but the position in the logs is respected.
4299
4300 <length> is the maximum number of characters to extract from the value and
4301 report in the logs. The string will be truncated on the right if
4302 it exceeds <length>.
4303
Willy Tarreau4460d032012-11-21 23:37:37 +01004304 The complete value of the last occurrence of the header is captured. The
Willy Tarreau0ba27502007-12-24 16:55:16 +01004305 result will be added to the logs between braces ('{}') after the captured
4306 request headers. If multiple headers are captured, they will be delimited by
4307 a vertical bar ('|') and will appear in the same order they were declared in
Willy Tarreaucc6c8912009-02-22 10:53:55 +01004308 the configuration. Non-existent headers will be logged just as an empty
4309 string. Common uses for response header captures include the "Content-length"
4310 header which indicates how many bytes are expected to be returned, the
4311 "Location" header to track redirections.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004312
Willy Tarreau0900abb2012-11-22 00:21:46 +01004313 There is no limit to the number of captured response headers nor to their
4314 length, though it is wise to keep them low to limit memory usage per session.
4315 In order to keep log format consistent for a same frontend, header captures
4316 can only be declared in a frontend. It is not possible to specify a capture
4317 in a "defaults" section.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004318
4319 Example:
4320 capture response header Content-length len 9
4321 capture response header Location len 15
4322
Willy Tarreauc57f0e22009-05-10 13:12:33 +02004323 See also : "capture cookie", "capture request header" as well as section 8
Willy Tarreau0ba27502007-12-24 16:55:16 +01004324 about logging.
4325
4326
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09004327clitcpka-cnt <count>
4328 Sets the maximum number of keepalive probes TCP should send before dropping
4329 the connection on the client side.
4330 May be used in sections : defaults | frontend | listen | backend
4331 yes | yes | yes | no
4332 Arguments :
4333 <count> is the maximum number of keepalive probes.
4334
4335 This keyword corresponds to the socket option TCP_KEEPCNT. If this keyword
4336 is not specified, system-wide TCP parameter (tcp_keepalive_probes) is used.
Willy Tarreau52543212020-07-09 05:58:51 +02004337 The availability of this setting depends on the operating system. It is
4338 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09004339
4340 See also : "option clitcpka", "clitcpka-idle", "clitcpka-intvl".
4341
4342
4343clitcpka-idle <timeout>
4344 Sets the time the connection needs to remain idle before TCP starts sending
4345 keepalive probes, if enabled the sending of TCP keepalive packets on the
4346 client side.
4347 May be used in sections : defaults | frontend | listen | backend
4348 yes | yes | yes | no
4349 Arguments :
4350 <timeout> is the time the connection needs to remain idle before TCP starts
4351 sending keepalive probes. It is specified in seconds by default,
4352 but can be in any other unit if the number is suffixed by the
4353 unit, as explained at the top of this document.
4354
4355 This keyword corresponds to the socket option TCP_KEEPIDLE. If this keyword
4356 is not specified, system-wide TCP parameter (tcp_keepalive_time) is used.
Willy Tarreau52543212020-07-09 05:58:51 +02004357 The availability of this setting depends on the operating system. It is
4358 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09004359
4360 See also : "option clitcpka", "clitcpka-cnt", "clitcpka-intvl".
4361
4362
4363clitcpka-intvl <timeout>
4364 Sets the time between individual keepalive probes on the client side.
4365 May be used in sections : defaults | frontend | listen | backend
4366 yes | yes | yes | no
4367 Arguments :
4368 <timeout> is the time between individual keepalive probes. It is specified
4369 in seconds by default, but can be in any other unit if the number
4370 is suffixed by the unit, as explained at the top of this
4371 document.
4372
4373 This keyword corresponds to the socket option TCP_KEEPINTVL. If this keyword
4374 is not specified, system-wide TCP parameter (tcp_keepalive_intvl) is used.
Willy Tarreau52543212020-07-09 05:58:51 +02004375 The availability of this setting depends on the operating system. It is
4376 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +09004377
4378 See also : "option clitcpka", "clitcpka-cnt", "clitcpka-idle".
4379
4380
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004381compression algo <algorithm> ...
4382compression type <mime type> ...
Willy Tarreau70737d12012-10-27 00:34:28 +02004383compression offload
William Lallemand82fe75c2012-10-23 10:25:10 +02004384 Enable HTTP compression.
4385 May be used in sections : defaults | frontend | listen | backend
4386 yes | yes | yes | yes
4387 Arguments :
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004388 algo is followed by the list of supported compression algorithms.
4389 type is followed by the list of MIME types that will be compressed.
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004390 offload makes HAProxy work as a compression offloader only (see notes).
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004391
4392 The currently supported algorithms are :
Willy Tarreauc91840a2015-03-28 17:00:39 +01004393 identity this is mostly for debugging, and it was useful for developing
4394 the compression feature. Identity does not apply any change on
4395 data.
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004396
Willy Tarreauc91840a2015-03-28 17:00:39 +01004397 gzip applies gzip compression. This setting is only available when
Baptiste Assmannf085d632015-12-21 17:57:32 +01004398 support for zlib or libslz was built in.
Willy Tarreauc91840a2015-03-28 17:00:39 +01004399
4400 deflate same as "gzip", but with deflate algorithm and zlib format.
4401 Note that this algorithm has ambiguous support on many
4402 browsers and no support at all from recent ones. It is
4403 strongly recommended not to use it for anything else than
4404 experimentation. This setting is only available when support
Baptiste Assmannf085d632015-12-21 17:57:32 +01004405 for zlib or libslz was built in.
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004406
Willy Tarreauc91840a2015-03-28 17:00:39 +01004407 raw-deflate same as "deflate" without the zlib wrapper, and used as an
4408 alternative when the browser wants "deflate". All major
4409 browsers understand it and despite violating the standards,
4410 it is known to work better than "deflate", at least on MSIE
4411 and some versions of Safari. Do not use it in conjunction
4412 with "deflate", use either one or the other since both react
4413 to the same Accept-Encoding token. This setting is only
Baptiste Assmannf085d632015-12-21 17:57:32 +01004414 available when support for zlib or libslz was built in.
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004415
Dmitry Sivachenko87c208b2012-11-22 20:03:26 +04004416 Compression will be activated depending on the Accept-Encoding request
Cyril Bonté316a8cf2012-11-11 13:38:27 +01004417 header. With identity, it does not take care of that header.
Dmitry Sivachenkoc9f3b452012-11-28 17:47:11 +04004418 If backend servers support HTTP compression, these directives
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004419 will be no-op: HAProxy will see the compressed response and will not
Dmitry Sivachenkoc9f3b452012-11-28 17:47:11 +04004420 compress again. If backend servers do not support HTTP compression and
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004421 there is Accept-Encoding header in request, HAProxy will compress the
Dmitry Sivachenkoc9f3b452012-11-28 17:47:11 +04004422 matching response.
Willy Tarreau70737d12012-10-27 00:34:28 +02004423
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004424 The "offload" setting makes HAProxy remove the Accept-Encoding header to
Willy Tarreau70737d12012-10-27 00:34:28 +02004425 prevent backend servers from compressing responses. It is strongly
4426 recommended not to do this because this means that all the compression work
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004427 will be done on the single point where HAProxy is located. However in some
4428 deployment scenarios, HAProxy may be installed in front of a buggy gateway
Dmitry Sivachenkoc9f3b452012-11-28 17:47:11 +04004429 with broken HTTP compression implementation which can't be turned off.
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004430 In that case HAProxy can be used to prevent that gateway from emitting
Dmitry Sivachenkoc9f3b452012-11-28 17:47:11 +04004431 invalid payloads. In this case, simply removing the header in the
4432 configuration does not work because it applies before the header is parsed,
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004433 so that prevents HAProxy from compressing. The "offload" setting should
Willy Tarreauffea9fd2014-07-12 16:37:02 +02004434 then be used for such scenarios. Note: for now, the "offload" setting is
4435 ignored when set in a defaults section.
William Lallemand82fe75c2012-10-23 10:25:10 +02004436
William Lallemand05097442012-11-20 12:14:28 +01004437 Compression is disabled when:
Baptiste Assmann650d53d2013-01-05 15:44:44 +01004438 * the request does not advertise a supported compression algorithm in the
4439 "Accept-Encoding" header
Julien Pivottoff80c822021-03-29 12:41:40 +02004440 * the response message is not HTTP/1.1 or above
Tim Duesterhusbb48c9a2019-01-30 23:46:04 +01004441 * HTTP status code is not one of 200, 201, 202, or 203
Baptiste Assmann650d53d2013-01-05 15:44:44 +01004442 * response contain neither a "Content-Length" header nor a
4443 "Transfer-Encoding" whose last value is "chunked"
4444 * response contains a "Content-Type" header whose first value starts with
4445 "multipart"
4446 * the response contains the "no-transform" value in the "Cache-control"
4447 header
4448 * User-Agent matches "Mozilla/4" unless it is MSIE 6 with XP SP2, or MSIE 7
4449 and later
4450 * The response contains a "Content-Encoding" header, indicating that the
4451 response is already compressed (see compression offload)
Tim Duesterhusbb48c9a2019-01-30 23:46:04 +01004452 * The response contains an invalid "ETag" header or multiple ETag headers
William Lallemand05097442012-11-20 12:14:28 +01004453
Tim Duesterhusb229f012019-01-29 16:38:56 +01004454 Note: The compression does not emit the Warning header.
William Lallemand05097442012-11-20 12:14:28 +01004455
William Lallemand82fe75c2012-10-23 10:25:10 +02004456 Examples :
4457 compression algo gzip
4458 compression type text/html text/plain
Willy Tarreau0ba27502007-12-24 16:55:16 +01004459
Christopher Fauletc3fe5332016-04-07 15:30:10 +02004460
Willy Tarreau55165fe2009-05-10 12:02:55 +02004461cookie <name> [ rewrite | insert | prefix ] [ indirect ] [ nocache ]
Willy Tarreau4992dd22012-05-31 21:02:17 +02004462 [ postonly ] [ preserve ] [ httponly ] [ secure ]
4463 [ domain <domain> ]* [ maxidle <idle> ] [ maxlife <life> ]
Christopher Faulet2f533902020-01-21 11:06:48 +01004464 [ dynamic ] [ attr <value> ]*
Willy Tarreau0ba27502007-12-24 16:55:16 +01004465 Enable cookie-based persistence in a backend.
4466 May be used in sections : defaults | frontend | listen | backend
4467 yes | no | yes | yes
4468 Arguments :
4469 <name> is the name of the cookie which will be monitored, modified or
4470 inserted in order to bring persistence. This cookie is sent to
4471 the client via a "Set-Cookie" header in the response, and is
4472 brought back by the client in a "Cookie" header in all requests.
4473 Special care should be taken to choose a name which does not
4474 conflict with any likely application cookie. Also, if the same
Davor Ocelice9ed2812017-12-25 17:49:28 +01004475 backends are subject to be used by the same clients (e.g.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004476 HTTP/HTTPS), care should be taken to use different cookie names
4477 between all backends if persistence between them is not desired.
4478
4479 rewrite This keyword indicates that the cookie will be provided by the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004480 server and that HAProxy will have to modify its value to set the
Willy Tarreau0ba27502007-12-24 16:55:16 +01004481 server's identifier in it. This mode is handy when the management
4482 of complex combinations of "Set-cookie" and "Cache-control"
4483 headers is left to the application. The application can then
4484 decide whether or not it is appropriate to emit a persistence
Lukas Tribusf01a9cd2016-02-03 18:09:37 +01004485 cookie. Since all responses should be monitored, this mode
4486 doesn't work in HTTP tunnel mode. Unless the application
Davor Ocelice9ed2812017-12-25 17:49:28 +01004487 behavior is very complex and/or broken, it is advised not to
Lukas Tribusf01a9cd2016-02-03 18:09:37 +01004488 start with this mode for new deployments. This keyword is
4489 incompatible with "insert" and "prefix".
Willy Tarreau0ba27502007-12-24 16:55:16 +01004490
4491 insert This keyword indicates that the persistence cookie will have to
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004492 be inserted by HAProxy in server responses if the client did not
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004493
Willy Tarreaua79094d2010-08-31 22:54:15 +02004494 already have a cookie that would have permitted it to access this
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004495 server. When used without the "preserve" option, if the server
Michael Prokop4438c602019-05-24 10:25:45 +02004496 emits a cookie with the same name, it will be removed before
Davor Ocelice9ed2812017-12-25 17:49:28 +01004497 processing. For this reason, this mode can be used to upgrade
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004498 existing configurations running in the "rewrite" mode. The cookie
4499 will only be a session cookie and will not be stored on the
4500 client's disk. By default, unless the "indirect" option is added,
4501 the server will see the cookies emitted by the client. Due to
4502 caching effects, it is generally wise to add the "nocache" or
4503 "postonly" keywords (see below). The "insert" keyword is not
4504 compatible with "rewrite" and "prefix".
Willy Tarreau0ba27502007-12-24 16:55:16 +01004505
4506 prefix This keyword indicates that instead of relying on a dedicated
4507 cookie for the persistence, an existing one will be completed.
4508 This may be needed in some specific environments where the client
4509 does not support more than one single cookie and the application
4510 already needs it. In this case, whenever the server sets a cookie
4511 named <name>, it will be prefixed with the server's identifier
4512 and a delimiter. The prefix will be removed from all client
4513 requests so that the server still finds the cookie it emitted.
4514 Since all requests and responses are subject to being modified,
Lukas Tribusf01a9cd2016-02-03 18:09:37 +01004515 this mode doesn't work with tunnel mode. The "prefix" keyword is
Willy Tarreau37229df2011-10-17 12:24:55 +02004516 not compatible with "rewrite" and "insert". Note: it is highly
4517 recommended not to use "indirect" with "prefix", otherwise server
4518 cookie updates would not be sent to clients.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004519
Willy Tarreaua79094d2010-08-31 22:54:15 +02004520 indirect When this option is specified, no cookie will be emitted to a
4521 client which already has a valid one for the server which has
4522 processed the request. If the server sets such a cookie itself,
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004523 it will be removed, unless the "preserve" option is also set. In
4524 "insert" mode, this will additionally remove cookies from the
4525 requests transmitted to the server, making the persistence
4526 mechanism totally transparent from an application point of view.
Willy Tarreau37229df2011-10-17 12:24:55 +02004527 Note: it is highly recommended not to use "indirect" with
4528 "prefix", otherwise server cookie updates would not be sent to
4529 clients.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004530
4531 nocache This option is recommended in conjunction with the insert mode
4532 when there is a cache between the client and HAProxy, as it
4533 ensures that a cacheable response will be tagged non-cacheable if
4534 a cookie needs to be inserted. This is important because if all
4535 persistence cookies are added on a cacheable home page for
4536 instance, then all customers will then fetch the page from an
4537 outer cache and will all share the same persistence cookie,
4538 leading to one server receiving much more traffic than others.
4539 See also the "insert" and "postonly" options.
4540
4541 postonly This option ensures that cookie insertion will only be performed
4542 on responses to POST requests. It is an alternative to the
4543 "nocache" option, because POST responses are not cacheable, so
4544 this ensures that the persistence cookie will never get cached.
4545 Since most sites do not need any sort of persistence before the
4546 first POST which generally is a login request, this is a very
4547 efficient method to optimize caching without risking to find a
4548 persistence cookie in the cache.
4549 See also the "insert" and "nocache" options.
4550
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004551 preserve This option may only be used with "insert" and/or "indirect". It
4552 allows the server to emit the persistence cookie itself. In this
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004553 case, if a cookie is found in the response, HAProxy will leave it
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004554 untouched. This is useful in order to end persistence after a
4555 logout request for instance. For this, the server just has to
Davor Ocelice9ed2812017-12-25 17:49:28 +01004556 emit a cookie with an invalid value (e.g. empty) or with a date in
Willy Tarreauba4c5be2010-10-23 12:46:42 +02004557 the past. By combining this mechanism with the "disable-on-404"
4558 check option, it is possible to perform a completely graceful
4559 shutdown because users will definitely leave the server after
4560 they logout.
4561
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004562 httponly This option tells HAProxy to add an "HttpOnly" cookie attribute
Willy Tarreau4992dd22012-05-31 21:02:17 +02004563 when a cookie is inserted. This attribute is used so that a
4564 user agent doesn't share the cookie with non-HTTP components.
4565 Please check RFC6265 for more information on this attribute.
4566
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004567 secure This option tells HAProxy to add a "Secure" cookie attribute when
Willy Tarreau4992dd22012-05-31 21:02:17 +02004568 a cookie is inserted. This attribute is used so that a user agent
4569 never emits this cookie over non-secure channels, which means
4570 that a cookie learned with this flag will be presented only over
4571 SSL/TLS connections. Please check RFC6265 for more information on
4572 this attribute.
4573
Krzysztof Piotr Oledzkiefe3b6f2008-05-23 23:49:32 +02004574 domain This option allows to specify the domain at which a cookie is
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01004575 inserted. It requires exactly one parameter: a valid domain
Willy Tarreau68a897b2009-12-03 23:28:34 +01004576 name. If the domain begins with a dot, the browser is allowed to
4577 use it for any host ending with that name. It is also possible to
4578 specify several domain names by invoking this option multiple
4579 times. Some browsers might have small limits on the number of
4580 domains, so be careful when doing that. For the record, sending
4581 10 domains to MSIE 6 or Firefox 2 works as expected.
Krzysztof Piotr Oledzkiefe3b6f2008-05-23 23:49:32 +02004582
Willy Tarreau996a92c2010-10-13 19:30:47 +02004583 maxidle This option allows inserted cookies to be ignored after some idle
4584 time. It only works with insert-mode cookies. When a cookie is
4585 sent to the client, the date this cookie was emitted is sent too.
4586 Upon further presentations of this cookie, if the date is older
4587 than the delay indicated by the parameter (in seconds), it will
4588 be ignored. Otherwise, it will be refreshed if needed when the
4589 response is sent to the client. This is particularly useful to
4590 prevent users who never close their browsers from remaining for
Davor Ocelice9ed2812017-12-25 17:49:28 +01004591 too long on the same server (e.g. after a farm size change). When
Willy Tarreau996a92c2010-10-13 19:30:47 +02004592 this option is set and a cookie has no date, it is always
4593 accepted, but gets refreshed in the response. This maintains the
4594 ability for admins to access their sites. Cookies that have a
4595 date in the future further than 24 hours are ignored. Doing so
4596 lets admins fix timezone issues without risking kicking users off
4597 the site.
4598
4599 maxlife This option allows inserted cookies to be ignored after some life
4600 time, whether they're in use or not. It only works with insert
4601 mode cookies. When a cookie is first sent to the client, the date
4602 this cookie was emitted is sent too. Upon further presentations
4603 of this cookie, if the date is older than the delay indicated by
4604 the parameter (in seconds), it will be ignored. If the cookie in
4605 the request has no date, it is accepted and a date will be set.
4606 Cookies that have a date in the future further than 24 hours are
4607 ignored. Doing so lets admins fix timezone issues without risking
4608 kicking users off the site. Contrary to maxidle, this value is
4609 not refreshed, only the first visit date counts. Both maxidle and
4610 maxlife may be used at the time. This is particularly useful to
4611 prevent users who never close their browsers from remaining for
Davor Ocelice9ed2812017-12-25 17:49:28 +01004612 too long on the same server (e.g. after a farm size change). This
Willy Tarreau996a92c2010-10-13 19:30:47 +02004613 is stronger than the maxidle method in that it forces a
4614 redispatch after some absolute delay.
4615
Olivier Houchard4e694042017-03-14 20:01:29 +01004616 dynamic Activate dynamic cookies. When used, a session cookie is
4617 dynamically created for each server, based on the IP and port
4618 of the server, and a secret key, specified in the
4619 "dynamic-cookie-key" backend directive.
4620 The cookie will be regenerated each time the IP address change,
4621 and is only generated for IPv4/IPv6.
4622
Daniel Corbett9f0843f2021-05-08 10:50:37 -04004623 attr This option tells HAProxy to add an extra attribute when a
Christopher Faulet2f533902020-01-21 11:06:48 +01004624 cookie is inserted. The attribute value can contain any
4625 characters except control ones or ";". This option may be
4626 repeated.
4627
Willy Tarreau0ba27502007-12-24 16:55:16 +01004628 There can be only one persistence cookie per HTTP backend, and it can be
4629 declared in a defaults section. The value of the cookie will be the value
4630 indicated after the "cookie" keyword in a "server" statement. If no cookie
4631 is declared for a given server, the cookie is not set.
Willy Tarreau6a06a402007-07-15 20:15:28 +02004632
Willy Tarreau0ba27502007-12-24 16:55:16 +01004633 Examples :
4634 cookie JSESSIONID prefix
4635 cookie SRV insert indirect nocache
4636 cookie SRV insert postonly indirect
Willy Tarreau996a92c2010-10-13 19:30:47 +02004637 cookie SRV insert indirect nocache maxidle 30m maxlife 8h
Willy Tarreau0ba27502007-12-24 16:55:16 +01004638
Willy Tarreau294d0f02015-08-10 19:40:12 +02004639 See also : "balance source", "capture cookie", "server" and "ignore-persist".
Willy Tarreau0ba27502007-12-24 16:55:16 +01004640
Willy Tarreau983e01e2010-01-11 18:42:06 +01004641
Thierry FOURNIERa0a1b752015-05-26 17:44:32 +02004642declare capture [ request | response ] len <length>
4643 Declares a capture slot.
4644 May be used in sections : defaults | frontend | listen | backend
4645 no | yes | yes | no
4646 Arguments:
4647 <length> is the length allowed for the capture.
4648
4649 This declaration is only available in the frontend or listen section, but the
4650 reserved slot can be used in the backends. The "request" keyword allocates a
4651 capture slot for use in the request, and "response" allocates a capture slot
4652 for use in the response.
4653
4654 See also: "capture-req", "capture-res" (sample converters),
Baptiste Assmann5ac425c2015-10-21 23:13:46 +02004655 "capture.req.hdr", "capture.res.hdr" (sample fetches),
Thierry FOURNIERa0a1b752015-05-26 17:44:32 +02004656 "http-request capture" and "http-response capture".
4657
4658
Krzysztof Piotr Oledzkic6df0662010-01-05 16:38:49 +01004659default-server [param*]
4660 Change default options for a server in a backend
4661 May be used in sections : defaults | frontend | listen | backend
4662 yes | no | yes | yes
4663 Arguments:
Willy Tarreau983e01e2010-01-11 18:42:06 +01004664 <param*> is a list of parameters for this server. The "default-server"
4665 keyword accepts an important number of options and has a complete
4666 section dedicated to it. Please refer to section 5 for more
4667 details.
Krzysztof Piotr Oledzkic6df0662010-01-05 16:38:49 +01004668
Willy Tarreau983e01e2010-01-11 18:42:06 +01004669 Example :
Krzysztof Piotr Oledzkic6df0662010-01-05 16:38:49 +01004670 default-server inter 1000 weight 13
4671
4672 See also: "server" and section 5 about server options
Willy Tarreau0ba27502007-12-24 16:55:16 +01004673
Willy Tarreau983e01e2010-01-11 18:42:06 +01004674
Willy Tarreau0ba27502007-12-24 16:55:16 +01004675default_backend <backend>
4676 Specify the backend to use when no "use_backend" rule has been matched.
4677 May be used in sections : defaults | frontend | listen | backend
4678 yes | yes | yes | no
4679 Arguments :
4680 <backend> is the name of the backend to use.
4681
4682 When doing content-switching between frontend and backends using the
4683 "use_backend" keyword, it is often useful to indicate which backend will be
4684 used when no rule has matched. It generally is the dynamic backend which
4685 will catch all undetermined requests.
4686
Willy Tarreau0ba27502007-12-24 16:55:16 +01004687 Example :
4688
4689 use_backend dynamic if url_dyn
4690 use_backend static if url_css url_img extension_img
4691 default_backend dynamic
4692
Willy Tarreau98d04852015-05-26 12:18:29 +02004693 See also : "use_backend"
Willy Tarreau2769aa02007-12-27 18:26:09 +01004694
Willy Tarreau0ba27502007-12-24 16:55:16 +01004695
Baptiste Assmann27f51342013-10-09 06:51:49 +02004696description <string>
4697 Describe a listen, frontend or backend.
4698 May be used in sections : defaults | frontend | listen | backend
4699 no | yes | yes | yes
4700 Arguments : string
4701
4702 Allows to add a sentence to describe the related object in the HAProxy HTML
4703 stats page. The description will be printed on the right of the object name
4704 it describes.
4705 No need to backslash spaces in the <string> arguments.
4706
4707
Willy Tarreau0ba27502007-12-24 16:55:16 +01004708disabled
4709 Disable a proxy, frontend or backend.
4710 May be used in sections : defaults | frontend | listen | backend
4711 yes | yes | yes | yes
4712 Arguments : none
4713
4714 The "disabled" keyword is used to disable an instance, mainly in order to
4715 liberate a listening port or to temporarily disable a service. The instance
4716 will still be created and its configuration will be checked, but it will be
4717 created in the "stopped" state and will appear as such in the statistics. It
4718 will not receive any traffic nor will it send any health-checks or logs. It
4719 is possible to disable many instances at once by adding the "disabled"
4720 keyword in a "defaults" section.
4721
4722 See also : "enabled"
4723
4724
Willy Tarreau5ce94572010-06-07 14:35:41 +02004725dispatch <address>:<port>
4726 Set a default server address
4727 May be used in sections : defaults | frontend | listen | backend
4728 no | no | yes | yes
Cyril Bonté108cf6e2012-04-21 23:30:29 +02004729 Arguments :
Willy Tarreau5ce94572010-06-07 14:35:41 +02004730
4731 <address> is the IPv4 address of the default server. Alternatively, a
4732 resolvable hostname is supported, but this name will be resolved
4733 during start-up.
4734
4735 <ports> is a mandatory port specification. All connections will be sent
4736 to this port, and it is not permitted to use port offsets as is
4737 possible with normal servers.
4738
Willy Tarreau787aed52011-04-15 06:45:37 +02004739 The "dispatch" keyword designates a default server for use when no other
Willy Tarreau5ce94572010-06-07 14:35:41 +02004740 server can take the connection. In the past it was used to forward non
4741 persistent connections to an auxiliary load balancer. Due to its simple
4742 syntax, it has also been used for simple TCP relays. It is recommended not to
4743 use it for more clarity, and to use the "server" directive instead.
4744
4745 See also : "server"
4746
Olivier Houchard4e694042017-03-14 20:01:29 +01004747
4748dynamic-cookie-key <string>
4749 Set the dynamic cookie secret key for a backend.
4750 May be used in sections : defaults | frontend | listen | backend
4751 yes | no | yes | yes
4752 Arguments : The secret key to be used.
4753
4754 When dynamic cookies are enabled (see the "dynamic" directive for cookie),
Davor Ocelice9ed2812017-12-25 17:49:28 +01004755 a dynamic cookie is created for each server (unless one is explicitly
Olivier Houchard4e694042017-03-14 20:01:29 +01004756 specified on the "server" line), using a hash of the IP address of the
4757 server, the TCP port, and the secret key.
Davor Ocelice9ed2812017-12-25 17:49:28 +01004758 That way, we can ensure session persistence across multiple load-balancers,
Olivier Houchard4e694042017-03-14 20:01:29 +01004759 even if servers are dynamically added or removed.
Willy Tarreau5ce94572010-06-07 14:35:41 +02004760
Willy Tarreau0ba27502007-12-24 16:55:16 +01004761enabled
4762 Enable a proxy, frontend or backend.
4763 May be used in sections : defaults | frontend | listen | backend
4764 yes | yes | yes | yes
4765 Arguments : none
4766
4767 The "enabled" keyword is used to explicitly enable an instance, when the
4768 defaults has been set to "disabled". This is very rarely used.
4769
4770 See also : "disabled"
4771
4772
4773errorfile <code> <file>
4774 Return a file contents instead of errors generated by HAProxy
4775 May be used in sections : defaults | frontend | listen | backend
4776 yes | yes | yes | yes
4777 Arguments :
4778 <code> is the HTTP status code. Currently, HAProxy is capable of
Christopher Faulet612f2ea2020-05-27 09:57:28 +02004779 generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
Christopher Faulete095f312020-12-07 11:22:24 +01004780 413, 425, 429, 500, 501, 502, 503, and 504.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004781
4782 <file> designates a file containing the full HTTP response. It is
Willy Tarreaud2a4aa22008-01-31 15:28:22 +01004783 recommended to follow the common practice of appending ".http" to
Willy Tarreau0ba27502007-12-24 16:55:16 +01004784 the filename so that people do not confuse the response with HTML
Willy Tarreau59140a22009-02-22 12:02:30 +01004785 error pages, and to use absolute paths, since files are read
4786 before any chroot is performed.
Willy Tarreau0ba27502007-12-24 16:55:16 +01004787
4788 It is important to understand that this keyword is not meant to rewrite
4789 errors returned by the server, but errors detected and returned by HAProxy.
4790 This is why the list of supported errors is limited to a small set.
4791
Willy Tarreauae94d4d2011-05-11 16:28:49 +02004792 Code 200 is emitted in response to requests matching a "monitor-uri" rule.
4793
Christopher Faulet70170672020-05-18 17:42:48 +02004794 The files are parsed when HAProxy starts and must be valid according to the
4795 HTTP specification. They should not exceed the configured buffer size
4796 (BUFSIZE), which generally is 16 kB, otherwise an internal error will be
4797 returned. It is also wise not to put any reference to local contents
4798 (e.g. images) in order to avoid loops between the client and HAProxy when all
4799 servers are down, causing an error to be returned instead of an
4800 image. Finally, The response cannot exceed (tune.bufsize - tune.maxrewrite)
4801 so that "http-after-response" rules still have room to operate (see
4802 "tune.maxrewrite").
Willy Tarreau59140a22009-02-22 12:02:30 +01004803
Willy Tarreau0ba27502007-12-24 16:55:16 +01004804 The files are read at the same time as the configuration and kept in memory.
4805 For this reason, the errors continue to be returned even when the process is
4806 chrooted, and no file change is considered while the process is running. A
Willy Tarreauc27debf2008-01-06 08:57:02 +01004807 simple method for developing those files consists in associating them to the
Willy Tarreau0ba27502007-12-24 16:55:16 +01004808 403 status code and interrogating a blocked URL.
4809
Christopher Faulet3b967c12020-05-15 15:47:44 +02004810 See also : "http-error", "errorloc", "errorloc302", "errorloc303"
Willy Tarreau0ba27502007-12-24 16:55:16 +01004811
Willy Tarreau59140a22009-02-22 12:02:30 +01004812 Example :
4813 errorfile 400 /etc/haproxy/errorfiles/400badreq.http
Willy Tarreau989222a2016-01-15 10:26:26 +01004814 errorfile 408 /dev/null # work around Chrome pre-connect bug
Willy Tarreau59140a22009-02-22 12:02:30 +01004815 errorfile 403 /etc/haproxy/errorfiles/403forbid.http
4816 errorfile 503 /etc/haproxy/errorfiles/503sorry.http
4817
Willy Tarreau2769aa02007-12-27 18:26:09 +01004818
Christopher Faulet76edc0f2020-01-13 15:52:01 +01004819errorfiles <name> [<code> ...]
4820 Import, fully or partially, the error files defined in the <name> http-errors
4821 section.
4822 May be used in sections : defaults | frontend | listen | backend
4823 yes | yes | yes | yes
4824 Arguments :
4825 <name> is the name of an existing http-errors section.
4826
4827 <code> is a HTTP status code. Several status code may be listed.
Christopher Faulet612f2ea2020-05-27 09:57:28 +02004828 Currently, HAProxy is capable of generating codes 200, 400, 401,
Christopher Faulete095f312020-12-07 11:22:24 +01004829 403, 404, 405, 407, 408, 410, 413, 425, 429, 500, 501, 502, 503,
4830 and 504.
Christopher Faulet76edc0f2020-01-13 15:52:01 +01004831
4832 Errors defined in the http-errors section with the name <name> are imported
4833 in the current proxy. If no status code is specified, all error files of the
4834 http-errors section are imported. Otherwise, only error files associated to
4835 the listed status code are imported. Those error files override the already
4836 defined custom errors for the proxy. And they may be overridden by following
Daniel Corbett67a82712020-07-06 23:01:19 -04004837 ones. Functionally, it is exactly the same as declaring all error files by
Christopher Faulet76edc0f2020-01-13 15:52:01 +01004838 hand using "errorfile" directives.
4839
Christopher Faulet3b967c12020-05-15 15:47:44 +02004840 See also : "http-error", "errorfile", "errorloc", "errorloc302" ,
4841 "errorloc303" and section 3.8 about http-errors.
Christopher Faulet76edc0f2020-01-13 15:52:01 +01004842
4843 Example :
4844 errorfiles generic
4845 errorfiles site-1 403 404
4846
4847
Willy Tarreau2769aa02007-12-27 18:26:09 +01004848errorloc <code> <url>
4849errorloc302 <code> <url>
4850 Return an HTTP redirection to a URL instead of errors generated by HAProxy
4851 May be used in sections : defaults | frontend | listen | backend
4852 yes | yes | yes | yes
4853 Arguments :
4854 <code> is the HTTP status code. Currently, HAProxy is capable of
Christopher Faulet612f2ea2020-05-27 09:57:28 +02004855 generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
Christopher Faulete095f312020-12-07 11:22:24 +01004856 413, 425, 429, 500, 501, 502, 503, and 504.
Willy Tarreau2769aa02007-12-27 18:26:09 +01004857
4858 <url> it is the exact contents of the "Location" header. It may contain
4859 either a relative URI to an error page hosted on the same site,
4860 or an absolute URI designating an error page on another site.
4861 Special care should be given to relative URIs to avoid redirect
Davor Ocelice9ed2812017-12-25 17:49:28 +01004862 loops if the URI itself may generate the same error (e.g. 500).
Willy Tarreau2769aa02007-12-27 18:26:09 +01004863
4864 It is important to understand that this keyword is not meant to rewrite
4865 errors returned by the server, but errors detected and returned by HAProxy.
4866 This is why the list of supported errors is limited to a small set.
4867
Willy Tarreauae94d4d2011-05-11 16:28:49 +02004868 Code 200 is emitted in response to requests matching a "monitor-uri" rule.
4869
Willy Tarreau2769aa02007-12-27 18:26:09 +01004870 Note that both keyword return the HTTP 302 status code, which tells the
4871 client to fetch the designated URL using the same HTTP method. This can be
4872 quite problematic in case of non-GET methods such as POST, because the URL
4873 sent to the client might not be allowed for something other than GET. To
Willy Tarreau989222a2016-01-15 10:26:26 +01004874 work around this problem, please use "errorloc303" which send the HTTP 303
Willy Tarreau2769aa02007-12-27 18:26:09 +01004875 status code, indicating to the client that the URL must be fetched with a GET
4876 request.
4877
Christopher Faulet3b967c12020-05-15 15:47:44 +02004878 See also : "http-error", "errorfile", "errorloc303"
Willy Tarreau2769aa02007-12-27 18:26:09 +01004879
4880
4881errorloc303 <code> <url>
4882 Return an HTTP redirection to a URL instead of errors generated by HAProxy
4883 May be used in sections : defaults | frontend | listen | backend
4884 yes | yes | yes | yes
4885 Arguments :
4886 <code> is the HTTP status code. Currently, HAProxy is capable of
Christopher Faulet612f2ea2020-05-27 09:57:28 +02004887 generating codes 200, 400, 401, 403, 404, 405, 407, 408, 410,
Christopher Faulete095f312020-12-07 11:22:24 +01004888 413, 425, 429, 500, 501, 502, 503, and 504.
Willy Tarreau2769aa02007-12-27 18:26:09 +01004889
4890 <url> it is the exact contents of the "Location" header. It may contain
4891 either a relative URI to an error page hosted on the same site,
4892 or an absolute URI designating an error page on another site.
4893 Special care should be given to relative URIs to avoid redirect
Davor Ocelice9ed2812017-12-25 17:49:28 +01004894 loops if the URI itself may generate the same error (e.g. 500).
Willy Tarreau2769aa02007-12-27 18:26:09 +01004895
4896 It is important to understand that this keyword is not meant to rewrite
4897 errors returned by the server, but errors detected and returned by HAProxy.
4898 This is why the list of supported errors is limited to a small set.
4899
Willy Tarreauae94d4d2011-05-11 16:28:49 +02004900 Code 200 is emitted in response to requests matching a "monitor-uri" rule.
4901
Willy Tarreau2769aa02007-12-27 18:26:09 +01004902 Note that both keyword return the HTTP 303 status code, which tells the
4903 client to fetch the designated URL using the same HTTP GET method. This
4904 solves the usual problems associated with "errorloc" and the 302 code. It is
4905 possible that some very old browsers designed before HTTP/1.1 do not support
Willy Tarreaud2a4aa22008-01-31 15:28:22 +01004906 it, but no such problem has been reported till now.
Willy Tarreau2769aa02007-12-27 18:26:09 +01004907
Christopher Faulet3b967c12020-05-15 15:47:44 +02004908 See also : "http-error", "errorfile", "errorloc", "errorloc302"
Willy Tarreau2769aa02007-12-27 18:26:09 +01004909
4910
Simon Horman51a1cf62015-02-03 13:00:44 +09004911email-alert from <emailaddr>
4912 Declare the from email address to be used in both the envelope and header
Davor Ocelice9ed2812017-12-25 17:49:28 +01004913 of email alerts. This is the address that email alerts are sent from.
Simon Horman51a1cf62015-02-03 13:00:44 +09004914 May be used in sections: defaults | frontend | listen | backend
4915 yes | yes | yes | yes
4916
4917 Arguments :
4918
4919 <emailaddr> is the from email address to use when sending email alerts
4920
4921 Also requires "email-alert mailers" and "email-alert to" to be set
4922 and if so sending email alerts is enabled for the proxy.
4923
Simon Horman64e34162015-02-06 11:11:57 +09004924 See also : "email-alert level", "email-alert mailers",
Cyril Bonté307ee1e2015-09-28 23:16:06 +02004925 "email-alert myhostname", "email-alert to", section 3.6 about
4926 mailers.
Simon Horman64e34162015-02-06 11:11:57 +09004927
4928
4929email-alert level <level>
4930 Declare the maximum log level of messages for which email alerts will be
4931 sent. This acts as a filter on the sending of email alerts.
4932 May be used in sections: defaults | frontend | listen | backend
4933 yes | yes | yes | yes
4934
4935 Arguments :
4936
4937 <level> One of the 8 syslog levels:
4938 emerg alert crit err warning notice info debug
4939 The above syslog levels are ordered from lowest to highest.
4940
4941 By default level is alert
4942
4943 Also requires "email-alert from", "email-alert mailers" and
4944 "email-alert to" to be set and if so sending email alerts is enabled
4945 for the proxy.
4946
Simon Horman1421e212015-04-30 13:10:35 +09004947 Alerts are sent when :
4948
4949 * An un-paused server is marked as down and <level> is alert or lower
4950 * A paused server is marked as down and <level> is notice or lower
4951 * A server is marked as up or enters the drain state and <level>
4952 is notice or lower
4953 * "option log-health-checks" is enabled, <level> is info or lower,
4954 and a health check status update occurs
4955
Simon Horman64e34162015-02-06 11:11:57 +09004956 See also : "email-alert from", "email-alert mailers",
4957 "email-alert myhostname", "email-alert to",
Simon Horman51a1cf62015-02-03 13:00:44 +09004958 section 3.6 about mailers.
4959
4960
4961email-alert mailers <mailersect>
4962 Declare the mailers to be used when sending email alerts
4963 May be used in sections: defaults | frontend | listen | backend
4964 yes | yes | yes | yes
4965
4966 Arguments :
4967
4968 <mailersect> is the name of the mailers section to send email alerts.
4969
4970 Also requires "email-alert from" and "email-alert to" to be set
4971 and if so sending email alerts is enabled for the proxy.
4972
Simon Horman64e34162015-02-06 11:11:57 +09004973 See also : "email-alert from", "email-alert level", "email-alert myhostname",
4974 "email-alert to", section 3.6 about mailers.
Simon Horman51a1cf62015-02-03 13:00:44 +09004975
4976
4977email-alert myhostname <hostname>
4978 Declare the to hostname address to be used when communicating with
4979 mailers.
4980 May be used in sections: defaults | frontend | listen | backend
4981 yes | yes | yes | yes
4982
4983 Arguments :
4984
Baptiste Assmann738bad92015-12-21 15:27:53 +01004985 <hostname> is the hostname to use when communicating with mailers
Simon Horman51a1cf62015-02-03 13:00:44 +09004986
4987 By default the systems hostname is used.
4988
4989 Also requires "email-alert from", "email-alert mailers" and
4990 "email-alert to" to be set and if so sending email alerts is enabled
4991 for the proxy.
4992
Simon Horman64e34162015-02-06 11:11:57 +09004993 See also : "email-alert from", "email-alert level", "email-alert mailers",
4994 "email-alert to", section 3.6 about mailers.
Simon Horman51a1cf62015-02-03 13:00:44 +09004995
4996
4997email-alert to <emailaddr>
Davor Ocelice9ed2812017-12-25 17:49:28 +01004998 Declare both the recipient address in the envelope and to address in the
Simon Horman51a1cf62015-02-03 13:00:44 +09004999 header of email alerts. This is the address that email alerts are sent to.
5000 May be used in sections: defaults | frontend | listen | backend
5001 yes | yes | yes | yes
5002
5003 Arguments :
5004
5005 <emailaddr> is the to email address to use when sending email alerts
5006
5007 Also requires "email-alert mailers" and "email-alert to" to be set
5008 and if so sending email alerts is enabled for the proxy.
5009
Simon Horman64e34162015-02-06 11:11:57 +09005010 See also : "email-alert from", "email-alert level", "email-alert mailers",
Simon Horman51a1cf62015-02-03 13:00:44 +09005011 "email-alert myhostname", section 3.6 about mailers.
5012
5013
Willy Tarreau4de91492010-01-22 19:10:05 +01005014force-persist { if | unless } <condition>
5015 Declare a condition to force persistence on down servers
5016 May be used in sections: defaults | frontend | listen | backend
Cyril Bonté4288c5a2018-03-12 22:02:59 +01005017 no | no | yes | yes
Willy Tarreau4de91492010-01-22 19:10:05 +01005018
5019 By default, requests are not dispatched to down servers. It is possible to
5020 force this using "option persist", but it is unconditional and redispatches
5021 to a valid server if "option redispatch" is set. That leaves with very little
5022 possibilities to force some requests to reach a server which is artificially
5023 marked down for maintenance operations.
5024
5025 The "force-persist" statement allows one to declare various ACL-based
5026 conditions which, when met, will cause a request to ignore the down status of
5027 a server and still try to connect to it. That makes it possible to start a
5028 server, still replying an error to the health checks, and run a specially
5029 configured browser to test the service. Among the handy methods, one could
5030 use a specific source IP address, or a specific cookie. The cookie also has
5031 the advantage that it can easily be added/removed on the browser from a test
5032 page. Once the service is validated, it is then possible to open the service
5033 to the world by returning a valid response to health checks.
5034
5035 The forced persistence is enabled when an "if" condition is met, or unless an
5036 "unless" condition is met. The final redispatch is always disabled when this
5037 is used.
5038
Cyril Bonté0d4bf012010-04-25 23:21:46 +02005039 See also : "option redispatch", "ignore-persist", "persist",
Cyril Bontéa8e7bbc2010-04-25 22:29:29 +02005040 and section 7 about ACL usage.
Willy Tarreau4de91492010-01-22 19:10:05 +01005041
Christopher Fauletc3fe5332016-04-07 15:30:10 +02005042
5043filter <name> [param*]
5044 Add the filter <name> in the filter list attached to the proxy.
5045 May be used in sections : defaults | frontend | listen | backend
5046 no | yes | yes | yes
5047 Arguments :
5048 <name> is the name of the filter. Officially supported filters are
5049 referenced in section 9.
5050
Tim Düsterhus4896c442016-11-29 02:15:19 +01005051 <param*> is a list of parameters accepted by the filter <name>. The
Christopher Fauletc3fe5332016-04-07 15:30:10 +02005052 parsing of these parameters are the responsibility of the
Tim Düsterhus4896c442016-11-29 02:15:19 +01005053 filter. Please refer to the documentation of the corresponding
5054 filter (section 9) for all details on the supported parameters.
Christopher Fauletc3fe5332016-04-07 15:30:10 +02005055
5056 Multiple occurrences of the filter line can be used for the same proxy. The
5057 same filter can be referenced many times if needed.
5058
5059 Example:
5060 listen
5061 bind *:80
5062
5063 filter trace name BEFORE-HTTP-COMP
5064 filter compression
5065 filter trace name AFTER-HTTP-COMP
5066
5067 compression algo gzip
5068 compression offload
5069
5070 server srv1 192.168.0.1:80
5071
5072 See also : section 9.
5073
Willy Tarreau4de91492010-01-22 19:10:05 +01005074
Willy Tarreau2769aa02007-12-27 18:26:09 +01005075fullconn <conns>
5076 Specify at what backend load the servers will reach their maxconn
5077 May be used in sections : defaults | frontend | listen | backend
5078 yes | no | yes | yes
5079 Arguments :
5080 <conns> is the number of connections on the backend which will make the
5081 servers use the maximal number of connections.
5082
Willy Tarreau198a7442008-01-17 12:05:32 +01005083 When a server has a "maxconn" parameter specified, it means that its number
Willy Tarreau2769aa02007-12-27 18:26:09 +01005084 of concurrent connections will never go higher. Additionally, if it has a
Willy Tarreau198a7442008-01-17 12:05:32 +01005085 "minconn" parameter, it indicates a dynamic limit following the backend's
Willy Tarreau2769aa02007-12-27 18:26:09 +01005086 load. The server will then always accept at least <minconn> connections,
5087 never more than <maxconn>, and the limit will be on the ramp between both
5088 values when the backend has less than <conns> concurrent connections. This
5089 makes it possible to limit the load on the servers during normal loads, but
5090 push it further for important loads without overloading the servers during
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01005091 exceptional loads.
Willy Tarreau2769aa02007-12-27 18:26:09 +01005092
Daniel Corbett9f0843f2021-05-08 10:50:37 -04005093 Since it's hard to get this value right, HAProxy automatically sets it to
Willy Tarreaufbb78422011-06-05 15:38:35 +02005094 10% of the sum of the maxconns of all frontends that may branch to this
Bertrand Jacquin702d44f2013-11-19 11:43:06 +01005095 backend (based on "use_backend" and "default_backend" rules). That way it's
5096 safe to leave it unset. However, "use_backend" involving dynamic names are
5097 not counted since there is no way to know if they could match or not.
Willy Tarreaufbb78422011-06-05 15:38:35 +02005098
Willy Tarreau2769aa02007-12-27 18:26:09 +01005099 Example :
5100 # The servers will accept between 100 and 1000 concurrent connections each
5101 # and the maximum of 1000 will be reached when the backend reaches 10000
5102 # connections.
5103 backend dynamic
5104 fullconn 10000
5105 server srv1 dyn1:80 minconn 100 maxconn 1000
5106 server srv2 dyn2:80 minconn 100 maxconn 1000
5107
5108 See also : "maxconn", "server"
5109
5110
Willy Tarreauab0a5192020-10-09 19:07:01 +02005111grace <time> (deprecated)
Willy Tarreau2769aa02007-12-27 18:26:09 +01005112 Maintain a proxy operational for some time after a soft stop
5113 May be used in sections : defaults | frontend | listen | backend
Cyril Bonté99ed3272010-01-24 23:29:44 +01005114 yes | yes | yes | yes
Willy Tarreau2769aa02007-12-27 18:26:09 +01005115 Arguments :
5116 <time> is the time (by default in milliseconds) for which the instance
5117 will remain operational with the frontend sockets still listening
5118 when a soft-stop is received via the SIGUSR1 signal.
5119
5120 This may be used to ensure that the services disappear in a certain order.
5121 This was designed so that frontends which are dedicated to monitoring by an
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01005122 external equipment fail immediately while other ones remain up for the time
Willy Tarreau2769aa02007-12-27 18:26:09 +01005123 needed by the equipment to detect the failure.
5124
5125 Note that currently, there is very little benefit in using this parameter,
5126 and it may in fact complicate the soft-reconfiguration process more than
5127 simplify it.
5128
Willy Tarreau0ba27502007-12-24 16:55:16 +01005129
Andrew Rodland17be45e2016-10-25 17:04:12 -04005130hash-balance-factor <factor>
5131 Specify the balancing factor for bounded-load consistent hashing
5132 May be used in sections : defaults | frontend | listen | backend
5133 yes | no | no | yes
5134 Arguments :
5135 <factor> is the control for the maximum number of concurrent requests to
5136 send to a server, expressed as a percentage of the average number
Frédéric Lécaille93d33162019-03-06 09:35:59 +01005137 of concurrent requests across all of the active servers.
Andrew Rodland17be45e2016-10-25 17:04:12 -04005138
5139 Specifying a "hash-balance-factor" for a server with "hash-type consistent"
5140 enables an algorithm that prevents any one server from getting too many
5141 requests at once, even if some hash buckets receive many more requests than
5142 others. Setting <factor> to 0 (the default) disables the feature. Otherwise,
5143 <factor> is a percentage greater than 100. For example, if <factor> is 150,
5144 then no server will be allowed to have a load more than 1.5 times the average.
5145 If server weights are used, they will be respected.
5146
5147 If the first-choice server is disqualified, the algorithm will choose another
5148 server based on the request hash, until a server with additional capacity is
5149 found. A higher <factor> allows more imbalance between the servers, while a
5150 lower <factor> means that more servers will be checked on average, affecting
5151 performance. Reasonable values are from 125 to 200.
5152
Willy Tarreau760e81d2018-05-03 07:20:40 +02005153 This setting is also used by "balance random" which internally relies on the
5154 consistent hashing mechanism.
5155
Andrew Rodland17be45e2016-10-25 17:04:12 -04005156 See also : "balance" and "hash-type".
5157
5158
Bhaskar Maddalab6c0ac92013-11-05 11:54:02 -05005159hash-type <method> <function> <modifier>
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02005160 Specify a method to use for mapping hashes to servers
5161 May be used in sections : defaults | frontend | listen | backend
5162 yes | no | yes | yes
5163 Arguments :
Bhaskar98634f02013-10-29 23:30:51 -04005164 <method> is the method used to select a server from the hash computed by
5165 the <function> :
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02005166
Bhaskar98634f02013-10-29 23:30:51 -04005167 map-based the hash table is a static array containing all alive servers.
5168 The hashes will be very smooth, will consider weights, but
5169 will be static in that weight changes while a server is up
5170 will be ignored. This means that there will be no slow start.
5171 Also, since a server is selected by its position in the array,
5172 most mappings are changed when the server count changes. This
5173 means that when a server goes up or down, or when a server is
5174 added to a farm, most connections will be redistributed to
5175 different servers. This can be inconvenient with caches for
5176 instance.
Willy Tarreau798a39c2010-11-24 15:04:29 +01005177
Bhaskar98634f02013-10-29 23:30:51 -04005178 consistent the hash table is a tree filled with many occurrences of each
5179 server. The hash key is looked up in the tree and the closest
5180 server is chosen. This hash is dynamic, it supports changing
5181 weights while the servers are up, so it is compatible with the
5182 slow start feature. It has the advantage that when a server
5183 goes up or down, only its associations are moved. When a
5184 server is added to the farm, only a few part of the mappings
5185 are redistributed, making it an ideal method for caches.
5186 However, due to its principle, the distribution will never be
5187 very smooth and it may sometimes be necessary to adjust a
5188 server's weight or its ID to get a more balanced distribution.
5189 In order to get the same distribution on multiple load
5190 balancers, it is important that all servers have the exact
Bhaskar Maddalab6c0ac92013-11-05 11:54:02 -05005191 same IDs. Note: consistent hash uses sdbm and avalanche if no
5192 hash function is specified.
Bhaskar98634f02013-10-29 23:30:51 -04005193
5194 <function> is the hash function to be used :
5195
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03005196 sdbm this function was created initially for sdbm (a public-domain
Bhaskar98634f02013-10-29 23:30:51 -04005197 reimplementation of ndbm) database library. It was found to do
5198 well in scrambling bits, causing better distribution of the keys
5199 and fewer splits. It also happens to be a good general hashing
Bhaskar Maddalab6c0ac92013-11-05 11:54:02 -05005200 function with good distribution, unless the total server weight
5201 is a multiple of 64, in which case applying the avalanche
5202 modifier may help.
Bhaskar98634f02013-10-29 23:30:51 -04005203
5204 djb2 this function was first proposed by Dan Bernstein many years ago
5205 on comp.lang.c. Studies have shown that for certain workload this
Bhaskar Maddalab6c0ac92013-11-05 11:54:02 -05005206 function provides a better distribution than sdbm. It generally
5207 works well with text-based inputs though it can perform extremely
5208 poorly with numeric-only input or when the total server weight is
5209 a multiple of 33, unless the avalanche modifier is also used.
5210
Daniel Corbett9f0843f2021-05-08 10:50:37 -04005211 wt6 this function was designed for HAProxy while testing other
Willy Tarreaua0f42712013-11-14 14:30:35 +01005212 functions in the past. It is not as smooth as the other ones, but
5213 is much less sensible to the input data set or to the number of
5214 servers. It can make sense as an alternative to sdbm+avalanche or
5215 djb2+avalanche for consistent hashing or when hashing on numeric
5216 data such as a source IP address or a visitor identifier in a URL
5217 parameter.
5218
Willy Tarreau324f07f2015-01-20 19:44:50 +01005219 crc32 this is the most common CRC32 implementation as used in Ethernet,
5220 gzip, PNG, etc. It is slower than the other ones but may provide
5221 a better distribution or less predictable results especially when
5222 used on strings.
5223
Bhaskar Maddalab6c0ac92013-11-05 11:54:02 -05005224 <modifier> indicates an optional method applied after hashing the key :
5225
5226 avalanche This directive indicates that the result from the hash
5227 function above should not be used in its raw form but that
5228 a 4-byte full avalanche hash must be applied first. The
5229 purpose of this step is to mix the resulting bits from the
5230 previous hash in order to avoid any undesired effect when
5231 the input contains some limited values or when the number of
5232 servers is a multiple of one of the hash's components (64
5233 for SDBM, 33 for DJB2). Enabling avalanche tends to make the
5234 result less predictable, but it's also not as smooth as when
5235 using the original function. Some testing might be needed
5236 with some workloads. This hash is one of the many proposed
5237 by Bob Jenkins.
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02005238
Bhaskar98634f02013-10-29 23:30:51 -04005239 The default hash type is "map-based" and is recommended for most usages. The
5240 default function is "sdbm", the selection of a function should be based on
5241 the range of the values being hashed.
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02005242
Andrew Rodland17be45e2016-10-25 17:04:12 -04005243 See also : "balance", "hash-balance-factor", "server"
Willy Tarreau6b2e11b2009-10-01 07:52:15 +02005244
5245
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005246http-after-response <action> <options...> [ { if | unless } <condition> ]
5247 Access control for all Layer 7 responses (server, applet/service and internal
5248 ones).
5249
5250 May be used in sections: defaults | frontend | listen | backend
5251 no | yes | yes | yes
5252
5253 The http-after-response statement defines a set of rules which apply to layer
5254 7 processing. The rules are evaluated in their declaration order when they
5255 are met in a frontend, listen or backend section. Any rule may optionally be
5256 followed by an ACL-based condition, in which case it will only be evaluated
5257 if the condition is true. Since these rules apply on responses, the backend
5258 rules are applied first, followed by the frontend's rules.
5259
5260 Unlike http-response rules, these ones are applied on all responses, the
5261 server ones but also to all responses generated by HAProxy. These rules are
5262 evaluated at the end of the responses analysis, before the data forwarding.
5263
5264 The first keyword is the rule's action. The supported actions are described
5265 below.
5266
5267 There is no limit to the number of http-after-response statements per
5268 instance.
5269
Christopher Fauletd5ac6de2020-12-02 08:40:14 +01005270 Note: Errors emitted in early stage of the request parsing are handled by the
5271 multiplexer at a lower level, before any http analysis. Thus no
5272 http-after-response ruleset is evaluated on these errors.
5273
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005274 Example:
5275 http-after-response set-header Strict-Transport-Security "max-age=31536000"
5276 http-after-response set-header Cache-Control "no-store,no-cache,private"
5277 http-after-response set-header Pragma "no-cache"
5278
5279http-after-response add-header <name> <fmt> [ { if | unless } <condition> ]
5280
5281 This appends an HTTP header field whose name is specified in <name> and whose
5282 value is defined by <fmt> which follows the log-format rules (see Custom Log
5283 Format in section 8.2.4). This may be used to send a cookie to a client for
5284 example, or to pass some internal information.
5285 This rule is not final, so it is possible to add other similar rules.
5286 Note that header addition is performed immediately, so one rule might reuse
5287 the resulting header from a previous rule.
5288
5289http-after-response allow [ { if | unless } <condition> ]
5290
5291 This stops the evaluation of the rules and lets the response pass the check.
5292 No further "http-after-response" rules are evaluated.
5293
Maciej Zdebebdd4c52020-11-20 13:58:48 +00005294http-after-response del-header <name> [ -m <meth> ] [ { if | unless } <condition> ]
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005295
Maciej Zdebebdd4c52020-11-20 13:58:48 +00005296 This removes all HTTP header fields whose name is specified in <name>. <meth>
5297 is the matching method, applied on the header name. Supported matching methods
5298 are "str" (exact match), "beg" (prefix match), "end" (suffix match), "sub"
5299 (substring match) and "reg" (regex match). If not specified, exact matching
5300 method is used.
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005301
5302http-after-response replace-header <name> <regex-match> <replace-fmt>
5303 [ { if | unless } <condition> ]
5304
5305 This works like "http-response replace-header".
5306
5307 Example:
5308 http-after-response replace-header Set-Cookie (C=[^;]*);(.*) \1;ip=%bi;\2
5309
5310 # applied to:
5311 Set-Cookie: C=1; expires=Tue, 14-Jun-2016 01:40:45 GMT
5312
5313 # outputs:
5314 Set-Cookie: C=1;ip=192.168.1.20; expires=Tue, 14-Jun-2016 01:40:45 GMT
5315
5316 # assuming the backend IP is 192.168.1.20.
5317
5318http-after-response replace-value <name> <regex-match> <replace-fmt>
5319 [ { if | unless } <condition> ]
5320
5321 This works like "http-response replace-value".
5322
5323 Example:
5324 http-after-response replace-value Cache-control ^public$ private
5325
5326 # applied to:
5327 Cache-Control: max-age=3600, public
5328
5329 # outputs:
5330 Cache-Control: max-age=3600, private
5331
5332http-after-response set-header <name> <fmt> [ { if | unless } <condition> ]
5333
5334 This does the same as "add-header" except that the header name is first
5335 removed if it existed. This is useful when passing security information to
5336 the server, where the header must not be manipulated by external users.
5337
5338http-after-response set-status <status> [reason <str>]
5339 [ { if | unless } <condition> ]
5340
5341 This replaces the response status code with <status> which must be an integer
5342 between 100 and 999. Optionally, a custom reason text can be provided defined
5343 by <str>, or the default reason for the specified code will be used as a
5344 fallback.
5345
5346 Example:
5347 # return "431 Request Header Fields Too Large"
5348 http-response set-status 431
5349 # return "503 Slow Down", custom reason
5350 http-response set-status 503 reason "Slow Down"
5351
5352http-after-response set-var(<var-name>) <expr> [ { if | unless } <condition> ]
5353
5354 This is used to set the contents of a variable. The variable is declared
5355 inline.
5356
5357 Arguments:
5358 <var-name> The name of the variable starts with an indication about its
5359 scope. The scopes allowed are:
5360 "proc" : the variable is shared with the whole process
5361 "sess" : the variable is shared with the whole session
5362 "txn" : the variable is shared with the transaction
5363 (request and response)
5364 "req" : the variable is shared only during request
5365 processing
5366 "res" : the variable is shared only during response
5367 processing
5368 This prefix is followed by a name. The separator is a '.'.
5369 The name may only contain characters 'a-z', 'A-Z', '0-9', '.'
5370 and '_'.
5371
5372 <expr> Is a standard HAProxy expression formed by a sample-fetch
5373 followed by some converters.
5374
5375 Example:
5376 http-after-response set-var(sess.last_redir) res.hdr(location)
5377
5378http-after-response strict-mode { on | off }
5379
5380 This enables or disables the strict rewriting mode for following rules. It
5381 does not affect rules declared before it and it is only applicable on rules
5382 performing a rewrite on the responses. When the strict mode is enabled, any
5383 rewrite failure triggers an internal error. Otherwise, such errors are
5384 silently ignored. The purpose of the strict rewriting mode is to make some
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05005385 rewrites optional while others must be performed to continue the response
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005386 processing.
5387
5388 By default, the strict rewriting mode is enabled. Its value is also reset
5389 when a ruleset evaluation ends. So, for instance, if you change the mode on
Daniel Corbett67a82712020-07-06 23:01:19 -04005390 the backend, the default mode is restored when HAProxy starts the frontend
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005391 rules evaluation.
5392
5393http-after-response unset-var(<var-name>) [ { if | unless } <condition> ]
5394
5395 This is used to unset a variable. See "http-after-response set-var" for
5396 details about <var-name>.
5397
5398 Example:
5399 http-after-response unset-var(sess.last_redir)
5400
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005401
5402http-check comment <string>
5403 Defines a comment for the following the http-check rule, reported in logs if
5404 it fails.
5405 May be used in sections : defaults | frontend | listen | backend
5406 yes | no | yes | yes
5407
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005408 Arguments :
5409 <string> is the comment message to add in logs if the following http-check
5410 rule fails.
5411
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005412 It only works for connect, send and expect rules. It is useful to make
5413 user-friendly error reporting.
5414
Daniel Corbett67a82712020-07-06 23:01:19 -04005415 See also : "option httpchk", "http-check connect", "http-check send" and
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005416 "http-check expect".
5417
5418
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005419http-check connect [default] [port <expr>] [addr <ip>] [send-proxy]
5420 [via-socks4] [ssl] [sni <sni>] [alpn <alpn>] [linger]
Christopher Fauletedc6ed92020-04-23 16:27:59 +02005421 [proto <name>] [comment <msg>]
Christopher Faulete5870d82020-04-15 11:32:03 +02005422 Opens a new connection to perform an HTTP health check
5423 May be used in sections : defaults | frontend | listen | backend
5424 yes | no | yes | yes
5425
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005426 Arguments :
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005427 comment <msg> defines a message to report if the rule evaluation fails.
5428
Christopher Faulete5870d82020-04-15 11:32:03 +02005429 default Use default options of the server line to do the health
Daniel Corbett67a82712020-07-06 23:01:19 -04005430 checks. The server options are used only if not redefined.
Christopher Faulete5870d82020-04-15 11:32:03 +02005431
5432 port <expr> if not set, check port or server port is used.
5433 It tells HAProxy where to open the connection to.
5434 <port> must be a valid TCP port source integer, from 1 to
5435 65535 or an sample-fetch expression.
5436
5437 addr <ip> defines the IP address to do the health check.
5438
5439 send-proxy send a PROXY protocol string
5440
5441 via-socks4 enables outgoing health checks using upstream socks4 proxy.
5442
5443 ssl opens a ciphered connection
5444
5445 sni <sni> specifies the SNI to use to do health checks over SSL.
5446
5447 alpn <alpn> defines which protocols to advertise with ALPN. The protocol
5448 list consists in a comma-delimited list of protocol names,
5449 for instance: "h2,http/1.1". If it is not set, the server ALPN
5450 is used.
5451
Christopher Fauletedc6ed92020-04-23 16:27:59 +02005452 proto <name> forces the multiplexer's protocol to use for this connection.
5453 It must be an HTTP mux protocol and it must be usable on the
5454 backend side. The list of available protocols is reported in
5455 haproxy -vv.
5456
Christopher Faulete5870d82020-04-15 11:32:03 +02005457 linger cleanly close the connection instead of using a single RST.
5458
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005459 Just like tcp-check health checks, it is possible to configure the connection
5460 to use to perform HTTP health check. This directive should also be used to
5461 describe a scenario involving several request/response exchanges, possibly on
5462 different ports or with different servers.
5463
5464 When there are no TCP port configured on the server line neither server port
5465 directive, then the first step of the http-check sequence must be to specify
5466 the port with a "http-check connect".
5467
5468 In an http-check ruleset a 'connect' is required, it is also mandatory to start
5469 the ruleset with a 'connect' rule. Purpose is to ensure admin know what they
5470 do.
5471
5472 When a connect must start the ruleset, if may still be preceded by set-var,
5473 unset-var or comment rules.
5474
5475 Examples :
Christopher Faulete5870d82020-04-15 11:32:03 +02005476 # check HTTP and HTTPs services on a server.
5477 # first open port 80 thanks to server line port directive, then
5478 # tcp-check opens port 443, ciphered and run a request on it:
5479 option httpchk
5480
5481 http-check connect
Christopher Fauleta5c14ef2020-04-29 14:19:13 +02005482 http-check send meth GET uri / ver HTTP/1.1 hdr host haproxy.1wt.eu
Christopher Faulet8021a5f2020-04-24 13:53:12 +02005483 http-check expect status 200-399
Christopher Faulete5870d82020-04-15 11:32:03 +02005484 http-check connect port 443 ssl sni haproxy.1wt.eu
Christopher Fauleta5c14ef2020-04-29 14:19:13 +02005485 http-check send meth GET uri / ver HTTP/1.1 hdr host haproxy.1wt.eu
Christopher Faulet8021a5f2020-04-24 13:53:12 +02005486 http-check expect status 200-399
Christopher Faulete5870d82020-04-15 11:32:03 +02005487
5488 server www 10.0.0.1 check port 80
5489
5490 See also : "option httpchk", "http-check send", "http-check expect"
Christopher Faulet6d0c3df2020-01-22 09:26:35 +01005491
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005492
Willy Tarreau0ba27502007-12-24 16:55:16 +01005493http-check disable-on-404
5494 Enable a maintenance mode upon HTTP/404 response to health-checks
5495 May be used in sections : defaults | frontend | listen | backend
Willy Tarreau2769aa02007-12-27 18:26:09 +01005496 yes | no | yes | yes
Willy Tarreau0ba27502007-12-24 16:55:16 +01005497 Arguments : none
5498
5499 When this option is set, a server which returns an HTTP code 404 will be
5500 excluded from further load-balancing, but will still receive persistent
5501 connections. This provides a very convenient method for Web administrators
5502 to perform a graceful shutdown of their servers. It is also important to note
5503 that a server which is detected as failed while it was in this mode will not
5504 generate an alert, just a notice. If the server responds 2xx or 3xx again, it
5505 will immediately be reinserted into the farm. The status on the stats page
5506 reports "NOLB" for a server in this mode. It is important to note that this
Willy Tarreaubd741542010-03-16 18:46:54 +01005507 option only works in conjunction with the "httpchk" option. If this option
5508 is used with "http-check expect", then it has precedence over it so that 404
Christopher Fauletfa8b89a2020-11-20 18:54:13 +01005509 responses will still be considered as soft-stop. Note also that a stopped
5510 server will stay stopped even if it replies 404s. This option is only
5511 evaluated for running servers.
Willy Tarreaubd741542010-03-16 18:46:54 +01005512
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005513 See also : "option httpchk" and "http-check expect".
Willy Tarreaubd741542010-03-16 18:46:54 +01005514
5515
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005516http-check expect [min-recv <int>] [comment <msg>]
Christopher Faulete5870d82020-04-15 11:32:03 +02005517 [ok-status <st>] [error-status <st>] [tout-status <st>]
5518 [on-success <fmt>] [on-error <fmt>] [status-code <expr>]
5519 [!] <match> <pattern>
Jamie Gloudonaaa21002012-08-25 00:18:33 -04005520 Make HTTP health checks consider response contents or specific status codes
Willy Tarreaubd741542010-03-16 18:46:54 +01005521 May be used in sections : defaults | frontend | listen | backend
Willy Tarreau1ee51a62011-08-19 20:04:17 +02005522 yes | no | yes | yes
Christopher Faulete5870d82020-04-15 11:32:03 +02005523
Willy Tarreaubd741542010-03-16 18:46:54 +01005524 Arguments :
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005525 comment <msg> defines a message to report if the rule evaluation fails.
5526
Christopher Faulete5870d82020-04-15 11:32:03 +02005527 min-recv is optional and can define the minimum amount of data required to
5528 evaluate the current expect rule. If the number of received bytes
5529 is under this limit, the check will wait for more data. This
5530 option can be used to resolve some ambiguous matching rules or to
5531 avoid executing costly regex matches on content known to be still
5532 incomplete. If an exact string is used, the minimum between the
5533 string length and this parameter is used. This parameter is
5534 ignored if it is set to -1. If the expect rule does not match,
5535 the check will wait for more data. If set to 0, the evaluation
5536 result is always conclusive.
5537
5538 ok-status <st> is optional and can be used to set the check status if
5539 the expect rule is successfully evaluated and if it is
5540 the last rule in the tcp-check ruleset. "L7OK", "L7OKC",
Christopher Fauletd888f0f2020-05-07 07:40:17 +02005541 "L6OK" and "L4OK" are supported :
5542 - L7OK : check passed on layer 7
Christopher Faulet83662b52020-11-20 17:47:47 +01005543 - L7OKC : check conditionally passed on layer 7, set
5544 server to NOLB state.
Christopher Fauletd888f0f2020-05-07 07:40:17 +02005545 - L6OK : check passed on layer 6
5546 - L4OK : check passed on layer 4
5547 By default "L7OK" is used.
Christopher Faulete5870d82020-04-15 11:32:03 +02005548
5549 error-status <st> is optional and can be used to set the check status if
5550 an error occurred during the expect rule evaluation.
Christopher Faulet83662b52020-11-20 17:47:47 +01005551 "L7OKC", "L7RSP", "L7STS", "L6RSP" and "L4CON" are
5552 supported :
5553 - L7OKC : check conditionally passed on layer 7, set
5554 server to NOLB state.
Christopher Fauletd888f0f2020-05-07 07:40:17 +02005555 - L7RSP : layer 7 invalid response - protocol error
5556 - L7STS : layer 7 response error, for example HTTP 5xx
5557 - L6RSP : layer 6 invalid response - protocol error
5558 - L4CON : layer 1-4 connection problem
5559 By default "L7RSP" is used.
Christopher Faulete5870d82020-04-15 11:32:03 +02005560
5561 tout-status <st> is optional and can be used to set the check status if
5562 a timeout occurred during the expect rule evaluation.
Christopher Fauletd888f0f2020-05-07 07:40:17 +02005563 "L7TOUT", "L6TOUT", and "L4TOUT" are supported :
5564 - L7TOUT : layer 7 (HTTP/SMTP) timeout
5565 - L6TOUT : layer 6 (SSL) timeout
5566 - L4TOUT : layer 1-4 timeout
Christopher Faulete5870d82020-04-15 11:32:03 +02005567 By default "L7TOUT" is used.
5568
5569 on-success <fmt> is optional and can be used to customize the
5570 informational message reported in logs if the expect
5571 rule is successfully evaluated and if it is the last rule
5572 in the tcp-check ruleset. <fmt> is a log-format string.
5573
5574 on-error <fmt> is optional and can be used to customize the
5575 informational message reported in logs if an error
5576 occurred during the expect rule evaluation. <fmt> is a
5577 log-format string.
5578
Willy Tarreaubd741542010-03-16 18:46:54 +01005579 <match> is a keyword indicating how to look for a specific pattern in the
Christopher Fauletb5594262020-05-05 20:23:13 +02005580 response. The keyword may be one of "status", "rstatus", "hdr",
5581 "fhdr", "string", or "rstring". The keyword may be preceded by an
Willy Tarreaubd741542010-03-16 18:46:54 +01005582 exclamation mark ("!") to negate the match. Spaces are allowed
5583 between the exclamation mark and the keyword. See below for more
5584 details on the supported keywords.
5585
Christopher Faulet39708192020-05-05 10:47:36 +02005586 <pattern> is the pattern to look for. It may be a string, a regular
5587 expression or a more complex pattern with several arguments. If
5588 the string pattern contains spaces, they must be escaped with the
5589 usual backslash ('\').
Willy Tarreaubd741542010-03-16 18:46:54 +01005590
5591 By default, "option httpchk" considers that response statuses 2xx and 3xx
5592 are valid, and that others are invalid. When "http-check expect" is used,
5593 it defines what is considered valid or invalid. Only one "http-check"
5594 statement is supported in a backend. If a server fails to respond or times
5595 out, the check obviously fails. The available matches are :
5596
Christopher Faulet8021a5f2020-04-24 13:53:12 +02005597 status <codes> : test the status codes found parsing <codes> string. it
5598 must be a comma-separated list of status codes or range
5599 codes. A health check response will be considered as
5600 valid if the response's status code matches any status
5601 code or is inside any range of the list. If the "status"
5602 keyword is prefixed with "!", then the response will be
5603 considered invalid if the status code matches.
Willy Tarreaubd741542010-03-16 18:46:54 +01005604
5605 rstatus <regex> : test a regular expression for the HTTP status code.
Jamie Gloudonaaa21002012-08-25 00:18:33 -04005606 A health check response will be considered valid if the
Willy Tarreaubd741542010-03-16 18:46:54 +01005607 response's status code matches the expression. If the
5608 "rstatus" keyword is prefixed with "!", then the response
5609 will be considered invalid if the status code matches.
5610 This is mostly used to check for multiple codes.
5611
Christopher Fauletb5594262020-05-05 20:23:13 +02005612 hdr { name | name-lf } [ -m <meth> ] <name>
5613 [ { value | value-lf } [ -m <meth> ] <value> :
Christopher Faulet39708192020-05-05 10:47:36 +02005614 test the specified header pattern on the HTTP response
5615 headers. The name pattern is mandatory but the value
5616 pattern is optional. If not specified, only the header
5617 presence is verified. <meth> is the matching method,
5618 applied on the header name or the header value. Supported
5619 matching methods are "str" (exact match), "beg" (prefix
5620 match), "end" (suffix match), "sub" (substring match) or
5621 "reg" (regex match). If not specified, exact matching
Christopher Fauletb5594262020-05-05 20:23:13 +02005622 method is used. If the "name-lf" parameter is used,
5623 <name> is evaluated as a log-format string. If "value-lf"
5624 parameter is used, <value> is evaluated as a log-format
5625 string. These parameters cannot be used with the regex
5626 matching method. Finally, the header value is considered
5627 as comma-separated list. Note that matchings are case
5628 insensitive on the header names.
5629
5630 fhdr { name | name-lf } [ -m <meth> ] <name>
5631 [ { value | value-lf } [ -m <meth> ] <value> :
5632 test the specified full header pattern on the HTTP
5633 response headers. It does exactly the same than "hdr"
5634 keyword, except the full header value is tested, commas
5635 are not considered as delimiters.
Christopher Faulet39708192020-05-05 10:47:36 +02005636
Willy Tarreaubd741542010-03-16 18:46:54 +01005637 string <string> : test the exact string match in the HTTP response body.
Jamie Gloudonaaa21002012-08-25 00:18:33 -04005638 A health check response will be considered valid if the
Willy Tarreaubd741542010-03-16 18:46:54 +01005639 response's body contains this exact string. If the
5640 "string" keyword is prefixed with "!", then the response
5641 will be considered invalid if the body contains this
5642 string. This can be used to look for a mandatory word at
5643 the end of a dynamic page, or to detect a failure when a
Davor Ocelice9ed2812017-12-25 17:49:28 +01005644 specific error appears on the check page (e.g. a stack
Willy Tarreaubd741542010-03-16 18:46:54 +01005645 trace).
5646
5647 rstring <regex> : test a regular expression on the HTTP response body.
Jamie Gloudonaaa21002012-08-25 00:18:33 -04005648 A health check response will be considered valid if the
Willy Tarreaubd741542010-03-16 18:46:54 +01005649 response's body matches this expression. If the "rstring"
5650 keyword is prefixed with "!", then the response will be
5651 considered invalid if the body matches the expression.
5652 This can be used to look for a mandatory word at the end
5653 of a dynamic page, or to detect a failure when a specific
Davor Ocelice9ed2812017-12-25 17:49:28 +01005654 error appears on the check page (e.g. a stack trace).
Willy Tarreaubd741542010-03-16 18:46:54 +01005655
Christopher Fauletaaab0832020-05-05 15:54:22 +02005656 string-lf <fmt> : test a log-format string match in the HTTP response body.
5657 A health check response will be considered valid if the
5658 response's body contains the string resulting of the
5659 evaluation of <fmt>, which follows the log-format rules.
5660 If prefixed with "!", then the response will be
5661 considered invalid if the body contains the string.
5662
Willy Tarreaubd741542010-03-16 18:46:54 +01005663 It is important to note that the responses will be limited to a certain size
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +01005664 defined by the global "tune.bufsize" option, which defaults to 16384 bytes.
Willy Tarreaubd741542010-03-16 18:46:54 +01005665 Thus, too large responses may not contain the mandatory pattern when using
5666 "string" or "rstring". If a large response is absolutely required, it is
5667 possible to change the default max size by setting the global variable.
5668 However, it is worth keeping in mind that parsing very large responses can
5669 waste some CPU cycles, especially when regular expressions are used, and that
5670 it is always better to focus the checks on smaller resources.
5671
Christopher Faulete5870d82020-04-15 11:32:03 +02005672 In an http-check ruleset, the last expect rule may be implicit. If no expect
5673 rule is specified after the last "http-check send", an implicit expect rule
5674 is defined to match on 2xx or 3xx status codes. It means this rule is also
5675 defined if there is no "http-check" rule at all, when only "option httpchk"
5676 is set.
Cyril Bonté32602d22015-01-30 00:07:07 +01005677
Willy Tarreaubd741542010-03-16 18:46:54 +01005678 Last, if "http-check expect" is combined with "http-check disable-on-404",
5679 then this last one has precedence when the server responds with 404.
5680
5681 Examples :
5682 # only accept status 200 as valid
Christopher Faulet8021a5f2020-04-24 13:53:12 +02005683 http-check expect status 200,201,300-310
Willy Tarreaubd741542010-03-16 18:46:54 +01005684
Christopher Faulet39708192020-05-05 10:47:36 +02005685 # be sure a sessid coookie is set
5686 http-check expect header name "set-cookie" value -m beg "sessid="
5687
Willy Tarreaubd741542010-03-16 18:46:54 +01005688 # consider SQL errors as errors
Willy Tarreau8f2a1e72011-01-06 16:36:10 +01005689 http-check expect ! string SQL\ Error
Willy Tarreaubd741542010-03-16 18:46:54 +01005690
5691 # consider status 5xx only as errors
Willy Tarreau8f2a1e72011-01-06 16:36:10 +01005692 http-check expect ! rstatus ^5
Willy Tarreaubd741542010-03-16 18:46:54 +01005693
5694 # check that we have a correct hexadecimal tag before /html
Jarno Huuskonene5ae7022017-04-03 14:36:21 +03005695 http-check expect rstring <!--tag:[0-9a-f]*--></html>
Willy Tarreau0ba27502007-12-24 16:55:16 +01005696
Christopher Faulete5870d82020-04-15 11:32:03 +02005697 See also : "option httpchk", "http-check connect", "http-check disable-on-404"
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005698 and "http-check send".
Willy Tarreau2769aa02007-12-27 18:26:09 +01005699
5700
Christopher Faulet7c95f5f2020-05-06 15:06:34 +02005701http-check send [meth <method>] [{ uri <uri> | uri-lf <fmt> }>] [ver <version>]
Christopher Faulet574e7bd2020-05-06 15:38:58 +02005702 [hdr <name> <fmt>]* [{ body <string> | body-lf <fmt> }]
5703 [comment <msg>]
Christopher Faulet8acb1282020-04-09 08:44:06 +02005704 Add a possible list of headers and/or a body to the request sent during HTTP
5705 health checks.
5706 May be used in sections : defaults | frontend | listen | backend
5707 yes | no | yes | yes
5708 Arguments :
Christopher Faulet4f5c2e22020-04-23 15:22:33 +02005709 comment <msg> defines a message to report if the rule evaluation fails.
5710
Christopher Faulete5870d82020-04-15 11:32:03 +02005711 meth <method> is the optional HTTP method used with the requests. When not
5712 set, the "OPTIONS" method is used, as it generally requires
5713 low server processing and is easy to filter out from the
5714 logs. Any method may be used, though it is not recommended
5715 to invent non-standard ones.
5716
Christopher Faulet7c95f5f2020-05-06 15:06:34 +02005717 uri <uri> is optional and set the URI referenced in the HTTP requests
5718 to the string <uri>. It defaults to "/" which is accessible
5719 by default on almost any server, but may be changed to any
5720 other URI. Query strings are permitted.
5721
5722 uri-lf <fmt> is optional and set the URI referenced in the HTTP requests
5723 using the log-format string <fmt>. It defaults to "/" which
5724 is accessible by default on almost any server, but may be
5725 changed to any other URI. Query strings are permitted.
Christopher Faulet8acb1282020-04-09 08:44:06 +02005726
Christopher Faulet907701b2020-04-28 09:37:00 +02005727 ver <version> is the optional HTTP version string. It defaults to
Christopher Faulete5870d82020-04-15 11:32:03 +02005728 "HTTP/1.0" but some servers might behave incorrectly in HTTP
Daniel Corbett67a82712020-07-06 23:01:19 -04005729 1.0, so turning it to HTTP/1.1 may sometimes help. Note that
Christopher Faulete5870d82020-04-15 11:32:03 +02005730 the Host field is mandatory in HTTP/1.1, use "hdr" argument
5731 to add it.
5732
5733 hdr <name> <fmt> adds the HTTP header field whose name is specified in
5734 <name> and whose value is defined by <fmt>, which follows
5735 to the log-format rules.
5736
5737 body <string> add the body defined by <string> to the request sent during
5738 HTTP health checks. If defined, the "Content-Length" header
5739 is thus automatically added to the request.
Christopher Faulet8acb1282020-04-09 08:44:06 +02005740
Christopher Faulet574e7bd2020-05-06 15:38:58 +02005741 body-lf <fmt> add the body defined by the log-format string <fmt> to the
5742 request sent during HTTP health checks. If defined, the
5743 "Content-Length" header is thus automatically added to the
5744 request.
5745
Christopher Faulet8acb1282020-04-09 08:44:06 +02005746 In addition to the request line defined by the "option httpchk" directive,
5747 this one is the valid way to add some headers and optionally a body to the
5748 request sent during HTTP health checks. If a body is defined, the associate
Christopher Faulet9df910c2020-04-29 14:20:47 +02005749 "Content-Length" header is automatically added. Thus, this header or
5750 "Transfer-encoding" header should not be present in the request provided by
5751 "http-check send". If so, it will be ignored. The old trick consisting to add
5752 headers after the version string on the "option httpchk" line is now
Amaury Denoyelle6d975f02020-12-22 14:08:52 +01005753 deprecated.
Christopher Faulet8acb1282020-04-09 08:44:06 +02005754
Christopher Faulete5870d82020-04-15 11:32:03 +02005755 Also "http-check send" doesn't support HTTP keep-alive. Keep in mind that it
Amaury Denoyelle6d975f02020-12-22 14:08:52 +01005756 will automatically append a "Connection: close" header, unless a Connection
5757 header has already already been configured via a hdr entry.
Christopher Faulet9df910c2020-04-29 14:20:47 +02005758
5759 Note that the Host header and the request authority, when both defined, are
5760 automatically synchronized. It means when the HTTP request is sent, when a
5761 Host is inserted in the request, the request authority is accordingly
5762 updated. Thus, don't be surprised if the Host header value overwrites the
5763 configured request authority.
5764
5765 Note also for now, no Host header is automatically added in HTTP/1.1 or above
5766 requests. You should add it explicitly.
Christopher Faulete5870d82020-04-15 11:32:03 +02005767
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005768 See also : "option httpchk", "http-check send-state" and "http-check expect".
Christopher Faulet8acb1282020-04-09 08:44:06 +02005769
5770
Willy Tarreauef781042010-01-27 11:53:01 +01005771http-check send-state
5772 Enable emission of a state header with HTTP health checks
5773 May be used in sections : defaults | frontend | listen | backend
5774 yes | no | yes | yes
5775 Arguments : none
5776
Daniel Corbett9f0843f2021-05-08 10:50:37 -04005777 When this option is set, HAProxy will systematically send a special header
Willy Tarreauef781042010-01-27 11:53:01 +01005778 "X-Haproxy-Server-State" with a list of parameters indicating to each server
Daniel Corbett9f0843f2021-05-08 10:50:37 -04005779 how they are seen by HAProxy. This can be used for instance when a server is
5780 manipulated without access to HAProxy and the operator needs to know whether
5781 HAProxy still sees it up or not, or if the server is the last one in a farm.
Willy Tarreauef781042010-01-27 11:53:01 +01005782
5783 The header is composed of fields delimited by semi-colons, the first of which
5784 is a word ("UP", "DOWN", "NOLB"), possibly followed by a number of valid
5785 checks on the total number before transition, just as appears in the stats
5786 interface. Next headers are in the form "<variable>=<value>", indicating in
5787 no specific order some values available in the stats interface :
Joseph Lynch514061c2015-01-15 17:52:59 -08005788 - a variable "address", containing the address of the backend server.
5789 This corresponds to the <address> field in the server declaration. For
5790 unix domain sockets, it will read "unix".
5791
5792 - a variable "port", containing the port of the backend server. This
5793 corresponds to the <port> field in the server declaration. For unix
5794 domain sockets, it will read "unix".
5795
Willy Tarreauef781042010-01-27 11:53:01 +01005796 - a variable "name", containing the name of the backend followed by a slash
5797 ("/") then the name of the server. This can be used when a server is
5798 checked in multiple backends.
5799
Daniel Corbett9f0843f2021-05-08 10:50:37 -04005800 - a variable "node" containing the name of the HAProxy node, as set in the
Willy Tarreauef781042010-01-27 11:53:01 +01005801 global "node" variable, otherwise the system's hostname if unspecified.
5802
5803 - a variable "weight" indicating the weight of the server, a slash ("/")
5804 and the total weight of the farm (just counting usable servers). This
5805 helps to know if other servers are available to handle the load when this
5806 one fails.
5807
5808 - a variable "scur" indicating the current number of concurrent connections
5809 on the server, followed by a slash ("/") then the total number of
5810 connections on all servers of the same backend.
5811
5812 - a variable "qcur" indicating the current number of requests in the
5813 server's queue.
5814
5815 Example of a header received by the application server :
5816 >>> X-Haproxy-Server-State: UP 2/3; name=bck/srv2; node=lb1; weight=1/2; \
5817 scur=13/22; qcur=0
5818
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005819 See also : "option httpchk", "http-check disable-on-404" and
5820 "http-check send".
Willy Tarreauef781042010-01-27 11:53:01 +01005821
Christopher Faulete5870d82020-04-15 11:32:03 +02005822
5823http-check set-var(<var-name>) <expr>
Christopher Faulete5870d82020-04-15 11:32:03 +02005824 This operation sets the content of a variable. The variable is declared inline.
Christopher Faulete5870d82020-04-15 11:32:03 +02005825 May be used in sections: defaults | frontend | listen | backend
5826 yes | no | yes | yes
5827
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005828 Arguments :
Christopher Faulete5870d82020-04-15 11:32:03 +02005829 <var-name> The name of the variable starts with an indication about its
5830 scope. The scopes allowed for http-check are:
5831 "proc" : the variable is shared with the whole process.
5832 "sess" : the variable is shared with the tcp-check session.
5833 "check": the variable is declared for the lifetime of the tcp-check.
5834 This prefix is followed by a name. The separator is a '.'.
5835 The name may only contain characters 'a-z', 'A-Z', '0-9', '.',
5836 and '-'.
5837
5838 <expr> Is a sample-fetch expression potentially followed by converters.
5839
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005840 Examples :
5841 http-check set-var(check.port) int(1234)
Christopher Faulete5870d82020-04-15 11:32:03 +02005842
5843
5844http-check unset-var(<var-name>)
Christopher Faulete5870d82020-04-15 11:32:03 +02005845 Free a reference to a variable within its scope.
Christopher Faulete5870d82020-04-15 11:32:03 +02005846 May be used in sections: defaults | frontend | listen | backend
5847 yes | no | yes | yes
5848
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005849 Arguments :
Christopher Faulete5870d82020-04-15 11:32:03 +02005850 <var-name> The name of the variable starts with an indication about its
5851 scope. The scopes allowed for http-check are:
5852 "proc" : the variable is shared with the whole process.
5853 "sess" : the variable is shared with the tcp-check session.
5854 "check": the variable is declared for the lifetime of the tcp-check.
5855 This prefix is followed by a name. The separator is a '.'.
5856 The name may only contain characters 'a-z', 'A-Z', '0-9', '.',
5857 and '-'.
5858
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02005859 Examples :
5860 http-check unset-var(check.port)
Christopher Faulete5870d82020-04-15 11:32:03 +02005861
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005862
Christopher Faulet3b967c12020-05-15 15:47:44 +02005863http-error status <code> [content-type <type>]
5864 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
5865 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
5866 [ hdr <name> <fmt> ]*
5867 Defines a custom error message to use instead of errors generated by HAProxy.
5868 May be used in sections : defaults | frontend | listen | backend
5869 yes | yes | yes | yes
5870 Arguments :
Ilya Shipitsin11057a32020-06-21 21:18:27 +05005871 status <code> is the HTTP status code. It must be specified.
Christopher Faulet3b967c12020-05-15 15:47:44 +02005872 Currently, HAProxy is capable of generating codes
Anthonin Bonnefoy85048f82020-06-22 09:17:01 +02005873 200, 400, 401, 403, 404, 405, 407, 408, 410, 413, 425,
Christopher Faulete095f312020-12-07 11:22:24 +01005874 429, 500, 501, 502, 503, and 504.
Christopher Faulet3b967c12020-05-15 15:47:44 +02005875
5876 content-type <type> is the response content type, for instance
5877 "text/plain". This parameter is ignored and should be
5878 omitted when an errorfile is configured or when the
5879 payload is empty. Otherwise, it must be defined.
5880
5881 default-errorfiles Reset the previously defined error message for current
5882 proxy for the status <code>. If used on a backend, the
5883 frontend error message is used, if defined. If used on
5884 a frontend, the default error message is used.
5885
5886 errorfile <file> designates a file containing the full HTTP response.
5887 It is recommended to follow the common practice of
5888 appending ".http" to the filename so that people do
5889 not confuse the response with HTML error pages, and to
5890 use absolute paths, since files are read before any
5891 chroot is performed.
5892
5893 errorfiles <name> designates the http-errors section to use to import
5894 the error message with the status code <code>. If no
5895 such message is found, the proxy's error messages are
5896 considered.
5897
5898 file <file> specifies the file to use as response payload. If the
5899 file is not empty, its content-type must be set as
5900 argument to "content-type", otherwise, any
5901 "content-type" argument is ignored. <file> is
5902 considered as a raw string.
5903
5904 string <str> specifies the raw string to use as response payload.
5905 The content-type must always be set as argument to
5906 "content-type".
5907
5908 lf-file <file> specifies the file to use as response payload. If the
5909 file is not empty, its content-type must be set as
5910 argument to "content-type", otherwise, any
5911 "content-type" argument is ignored. <file> is
5912 evaluated as a log-format string.
5913
5914 lf-string <str> specifies the log-format string to use as response
5915 payload. The content-type must always be set as
5916 argument to "content-type".
5917
5918 hdr <name> <fmt> adds to the response the HTTP header field whose name
5919 is specified in <name> and whose value is defined by
5920 <fmt>, which follows to the log-format rules.
5921 This parameter is ignored if an errorfile is used.
5922
5923 This directive may be used instead of "errorfile", to define a custom error
5924 message. As "errorfile" directive, it is used for errors detected and
5925 returned by HAProxy. If an errorfile is defined, it is parsed when HAProxy
5926 starts and must be valid according to the HTTP standards. The generated
5927 response must not exceed the configured buffer size (BUFFSIZE), otherwise an
5928 internal error will be returned. Finally, if you consider to use some
5929 http-after-response rules to rewrite these errors, the reserved buffer space
5930 should be available (see "tune.maxrewrite").
5931
5932 The files are read at the same time as the configuration and kept in memory.
5933 For this reason, the errors continue to be returned even when the process is
5934 chrooted, and no file change is considered while the process is running.
5935
Christopher Fauletd5ac6de2020-12-02 08:40:14 +01005936 Note: 400/408/500 errors emitted in early stage of the request parsing are
5937 handled by the multiplexer at a lower level. No custom formatting is
5938 supported at this level. Thus only static error messages, defined with
5939 "errorfile" directive, are supported. However, this limitation only
5940 exists during the request headers parsing or between two transactions.
5941
Christopher Faulet3b967c12020-05-15 15:47:44 +02005942 See also : "errorfile", "errorfiles", "errorloc", "errorloc302",
5943 "errorloc303" and section 3.8 about http-errors.
5944
5945
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005946http-request <action> [options...] [ { if | unless } <condition> ]
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01005947 Access control for Layer 7 requests
5948
5949 May be used in sections: defaults | frontend | listen | backend
5950 no | yes | yes | yes
5951
Willy Tarreau20b0de52012-12-24 15:45:22 +01005952 The http-request statement defines a set of rules which apply to layer 7
5953 processing. The rules are evaluated in their declaration order when they are
5954 met in a frontend, listen or backend section. Any rule may optionally be
5955 followed by an ACL-based condition, in which case it will only be evaluated
5956 if the condition is true.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01005957
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005958 The first keyword is the rule's action. The supported actions are described
5959 below.
Willy Tarreau20b0de52012-12-24 15:45:22 +01005960
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005961 There is no limit to the number of http-request statements per instance.
Willy Tarreau20b0de52012-12-24 15:45:22 +01005962
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005963 Example:
5964 acl nagios src 192.168.129.3
5965 acl local_net src 192.168.0.0/16
5966 acl auth_ok http_auth(L1)
Willy Tarreau20b0de52012-12-24 15:45:22 +01005967
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005968 http-request allow if nagios
5969 http-request allow if local_net auth_ok
5970 http-request auth realm Gimme if local_net auth_ok
5971 http-request deny
Willy Tarreau81499eb2012-12-27 12:19:02 +01005972
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005973 Example:
5974 acl key req.hdr(X-Add-Acl-Key) -m found
5975 acl add path /addacl
5976 acl del path /delacl
Willy Tarreau20b0de52012-12-24 15:45:22 +01005977
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005978 acl myhost hdr(Host) -f myhost.lst
Willy Tarreau20b0de52012-12-24 15:45:22 +01005979
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005980 http-request add-acl(myhost.lst) %[req.hdr(X-Add-Acl-Key)] if key add
5981 http-request del-acl(myhost.lst) %[req.hdr(X-Add-Acl-Key)] if key del
Thierry FOURNIERdad3d1d2014-04-22 18:07:25 +02005982
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005983 Example:
5984 acl value req.hdr(X-Value) -m found
5985 acl setmap path /setmap
5986 acl delmap path /delmap
Sasha Pachev218f0642014-06-16 12:05:59 -06005987
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005988 use_backend bk_appli if { hdr(Host),map_str(map.lst) -m found }
Sasha Pachev218f0642014-06-16 12:05:59 -06005989
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005990 http-request set-map(map.lst) %[src] %[req.hdr(X-Value)] if setmap value
5991 http-request del-map(map.lst) %[src] if delmap
Sasha Pachev218f0642014-06-16 12:05:59 -06005992
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005993 See also : "stats http-request", section 3.4 about userlists and section 7
5994 about ACL usage.
Sasha Pachev218f0642014-06-16 12:05:59 -06005995
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005996http-request add-acl(<file-name>) <key fmt> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06005997
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02005998 This is used to add a new entry into an ACL. The ACL must be loaded from a
5999 file (even a dummy empty file). The file name of the ACL to be updated is
6000 passed between parentheses. It takes one argument: <key fmt>, which follows
6001 log-format rules, to collect content of the new entry. It performs a lookup
6002 in the ACL before insertion, to avoid duplicated (or more) values. This
6003 lookup is done by a linear search and can be expensive with large lists!
6004 It is the equivalent of the "add acl" command from the stats socket, but can
6005 be triggered by an HTTP request.
Sasha Pachev218f0642014-06-16 12:05:59 -06006006
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006007http-request add-header <name> <fmt> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06006008
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006009 This appends an HTTP header field whose name is specified in <name> and
6010 whose value is defined by <fmt> which follows the log-format rules (see
6011 Custom Log Format in section 8.2.4). This is particularly useful to pass
6012 connection-specific information to the server (e.g. the client's SSL
6013 certificate), or to combine several headers into one. This rule is not
6014 final, so it is possible to add other similar rules. Note that header
6015 addition is performed immediately, so one rule might reuse the resulting
6016 header from a previous rule.
Sasha Pachev218f0642014-06-16 12:05:59 -06006017
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006018http-request allow [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06006019
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006020 This stops the evaluation of the rules and lets the request pass the check.
6021 No further "http-request" rules are evaluated.
Sasha Pachev218f0642014-06-16 12:05:59 -06006022
Sasha Pachev218f0642014-06-16 12:05:59 -06006023
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006024http-request auth [realm <realm>] [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06006025
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006026 This stops the evaluation of the rules and immediately responds with an
6027 HTTP 401 or 407 error code to invite the user to present a valid user name
6028 and password. No further "http-request" rules are evaluated. An optional
6029 "realm" parameter is supported, it sets the authentication realm that is
6030 returned with the response (typically the application's name).
Sasha Pachev218f0642014-06-16 12:05:59 -06006031
Christopher Faulet612f2ea2020-05-27 09:57:28 +02006032 The corresponding proxy's error message is used. It may be customized using
6033 an "errorfile" or an "http-error" directive. For 401 responses, all
6034 occurrences of the WWW-Authenticate header are removed and replaced by a new
6035 one with a basic authentication challenge for realm "<realm>". For 407
6036 responses, the same is done on the Proxy-Authenticate header. If the error
6037 message must not be altered, consider to use "http-request return" rule
6038 instead.
6039
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006040 Example:
6041 acl auth_ok http_auth_group(L1) G1
6042 http-request auth unless auth_ok
Sasha Pachev218f0642014-06-16 12:05:59 -06006043
Jarno Huuskonen251a6b72019-01-04 14:05:02 +02006044http-request cache-use <name> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06006045
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02006046 See section 6.2 about cache setup.
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006047
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006048http-request capture <sample> [ len <length> | id <id> ]
6049 [ { if | unless } <condition> ]
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006050
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006051 This captures sample expression <sample> from the request buffer, and
6052 converts it to a string of at most <len> characters. The resulting string is
6053 stored into the next request "capture" slot, so it will possibly appear next
6054 to some captured HTTP headers. It will then automatically appear in the logs,
6055 and it will be possible to extract it using sample fetch rules to feed it
6056 into headers or anything. The length should be limited given that this size
6057 will be allocated for each capture during the whole session life.
6058 Please check section 7.3 (Fetching samples) and "capture request header" for
6059 more information.
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006060
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006061 If the keyword "id" is used instead of "len", the action tries to store the
6062 captured string in a previously declared capture slot. This is useful to run
6063 captures in backends. The slot id can be declared by a previous directive
Baptiste Assmann19a69b32020-01-16 14:34:22 +01006064 "http-request capture" or with the "declare capture" keyword.
6065
6066 When using this action in a backend, double check that the relevant
6067 frontend(s) have the required capture slots otherwise, this rule will be
6068 ignored at run time. This can't be detected at configuration parsing time
6069 due to HAProxy's ability to dynamically resolve backend name at runtime.
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006070
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006071http-request del-acl(<file-name>) <key fmt> [ { if | unless } <condition> ]
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006072
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006073 This is used to delete an entry from an ACL. The ACL must be loaded from a
6074 file (even a dummy empty file). The file name of the ACL to be updated is
6075 passed between parentheses. It takes one argument: <key fmt>, which follows
6076 log-format rules, to collect content of the entry to delete.
6077 It is the equivalent of the "del acl" command from the stats socket, but can
6078 be triggered by an HTTP request.
Willy Tarreaua0dc23f2015-01-22 20:46:11 +01006079
Maciej Zdebebdd4c52020-11-20 13:58:48 +00006080http-request del-header <name> [ -m <meth> ] [ { if | unless } <condition> ]
Willy Tarreauf4c43c12013-06-11 17:01:13 +02006081
Maciej Zdebebdd4c52020-11-20 13:58:48 +00006082 This removes all HTTP header fields whose name is specified in <name>. <meth>
6083 is the matching method, applied on the header name. Supported matching methods
6084 are "str" (exact match), "beg" (prefix match), "end" (suffix match), "sub"
6085 (substring match) and "reg" (regex match). If not specified, exact matching
6086 method is used.
Willy Tarreau9a355ec2013-06-11 17:45:46 +02006087
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006088http-request del-map(<file-name>) <key fmt> [ { if | unless } <condition> ]
Willy Tarreau42cf39e2013-06-11 18:51:32 +02006089
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006090 This is used to delete an entry from a MAP. The MAP must be loaded from a
6091 file (even a dummy empty file). The file name of the MAP to be updated is
6092 passed between parentheses. It takes one argument: <key fmt>, which follows
6093 log-format rules, to collect content of the entry to delete.
6094 It takes one argument: "file name" It is the equivalent of the "del map"
6095 command from the stats socket, but can be triggered by an HTTP request.
Willy Tarreau51347ed2013-06-11 19:34:13 +02006096
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006097http-request deny [deny_status <status>] [ { if | unless } <condition> ]
6098http-request deny [ { status | deny_status } <code>] [content-type <type>]
6099 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
6100 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
6101 [ hdr <name> <fmt> ]*
6102 [ { if | unless } <condition> ]
Patrick Hemmer268a7072018-05-11 12:52:31 -04006103
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006104 This stops the evaluation of the rules and immediately rejects the request.
6105 By default an HTTP 403 error is returned. But the response may be customized
6106 using same syntax than "http-request return" rules. Thus, see "http-request
Ilya Shipitsin11057a32020-06-21 21:18:27 +05006107 return" for details. For compatibility purpose, when no argument is defined,
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006108 or only "deny_status", the argument "default-errorfiles" is implied. It means
6109 "http-request deny [deny_status <status>]" is an alias of
6110 "http-request deny [status <status>] default-errorfiles".
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006111 No further "http-request" rules are evaluated.
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006112 See also "http-request return".
Patrick Hemmer268a7072018-05-11 12:52:31 -04006113
Olivier Houchard602bf7d2019-05-10 13:59:15 +02006114http-request disable-l7-retry [ { if | unless } <condition> ]
6115 This disables any attempt to retry the request if it fails for any other
6116 reason than a connection failure. This can be useful for example to make
6117 sure POST requests aren't retried on failure.
6118
Baptiste Assmann333939c2019-01-21 08:34:50 +01006119http-request do-resolve(<var>,<resolvers>,[ipv4,ipv6]) <expr> :
6120
6121 This action performs a DNS resolution of the output of <expr> and stores
6122 the result in the variable <var>. It uses the DNS resolvers section
6123 pointed by <resolvers>.
6124 It is possible to choose a resolution preference using the optional
6125 arguments 'ipv4' or 'ipv6'.
6126 When performing the DNS resolution, the client side connection is on
6127 pause waiting till the end of the resolution.
6128 If an IP address can be found, it is stored into <var>. If any kind of
6129 error occurs, then <var> is not set.
6130 One can use this action to discover a server IP address at run time and
6131 based on information found in the request (IE a Host header).
6132 If this action is used to find the server's IP address (using the
6133 "set-dst" action), then the server IP address in the backend must be set
6134 to 0.0.0.0.
6135
6136 Example:
6137 resolvers mydns
6138 nameserver local 127.0.0.53:53
6139 nameserver google 8.8.8.8:53
6140 timeout retry 1s
6141 hold valid 10s
6142 hold nx 3s
6143 hold other 3s
6144 hold obsolete 0s
6145 accepted_payload_size 8192
6146
6147 frontend fe
6148 bind 10.42.0.1:80
6149 http-request do-resolve(txn.myip,mydns,ipv4) hdr(Host),lower
6150 http-request capture var(txn.myip) len 40
6151
6152 # return 503 when the variable is not set,
6153 # which mean DNS resolution error
6154 use_backend b_503 unless { var(txn.myip) -m found }
6155
6156 default_backend be
6157
6158 backend b_503
6159 # dummy backend used to return 503.
6160 # one can use the errorfile directive to send a nice
6161 # 503 error page to end users
6162
6163 backend be
6164 # rule to prevent HAProxy from reconnecting to services
6165 # on the local network (forged DNS name used to scan the network)
6166 http-request deny if { var(txn.myip) -m ip 127.0.0.0/8 10.0.0.0/8 }
6167 http-request set-dst var(txn.myip)
6168 server clear 0.0.0.0:0
6169
6170 NOTE: Don't forget to set the "protection" rules to ensure HAProxy won't
6171 be used to scan the network or worst won't loop over itself...
6172
Frédéric Lécaille06f5b642018-11-12 11:01:10 +01006173http-request early-hint <name> <fmt> [ { if | unless } <condition> ]
6174
6175 This is used to build an HTTP 103 Early Hints response prior to any other one.
6176 This appends an HTTP header field to this response whose name is specified in
6177 <name> and whose value is defined by <fmt> which follows the log-format rules
6178 (see Custom Log Format in section 8.2.4). This is particularly useful to pass
Frédéric Lécaille3aac1062018-11-13 09:42:13 +01006179 to the client some Link headers to preload resources required to render the
6180 HTML documents.
Frédéric Lécaille06f5b642018-11-12 11:01:10 +01006181
6182 See RFC 8297 for more information.
6183
Tim Duesterhusd371e992021-04-15 21:45:58 +02006184http-request normalize-uri <normalizer> [ { if | unless } <condition> ]
Tim Duesterhusdec1c362021-05-10 17:28:26 +02006185http-request normalize-uri fragment-encode [ { if | unless } <condition> ]
Tim Duesterhusc9e05ab2021-05-10 17:28:25 +02006186http-request normalize-uri fragment-strip [ { if | unless } <condition> ]
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006187http-request normalize-uri path-merge-slashes [ { if | unless } <condition> ]
Maximilian Maderff3bb8b2021-04-21 00:22:50 +02006188http-request normalize-uri path-strip-dot [ { if | unless } <condition> ]
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006189http-request normalize-uri path-strip-dotdot [ full ] [ { if | unless } <condition> ]
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006190http-request normalize-uri percent-decode-unreserved [ strict ] [ { if | unless } <condition> ]
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006191http-request normalize-uri percent-to-uppercase [ strict ] [ { if | unless } <condition> ]
6192http-request normalize-uri query-sort-by-name [ { if | unless } <condition> ]
Tim Duesterhusd371e992021-04-15 21:45:58 +02006193
Tim Duesterhusb918a4a2021-04-16 23:52:29 +02006194 Performs normalization of the request's URI.
6195
Tim Duesterhus2963fd32021-04-17 00:24:56 +02006196 URI normalization in HAProxy 2.4 is currently available as an experimental
Amaury Denoyellea9e639a2021-05-06 15:50:12 +02006197 technical preview. As such, it requires the global directive
6198 'expose-experimental-directives' first to be able to invoke it. You should be
6199 prepared that the behavior of normalizers might change to fix possible
6200 issues, possibly breaking proper request processing in your infrastructure.
Tim Duesterhus2963fd32021-04-17 00:24:56 +02006201
Tim Duesterhusb918a4a2021-04-16 23:52:29 +02006202 Each normalizer handles a single type of normalization to allow for a
6203 fine-grained selection of the level of normalization that is appropriate for
6204 the supported backend.
6205
6206 As an example the "path-strip-dotdot" normalizer might be useful for a static
6207 fileserver that directly maps the requested URI to the path within the local
6208 filesystem. However it might break routing of an API that expects a specific
6209 number of segments in the path.
6210
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006211 It is important to note that some normalizers might result in unsafe
6212 transformations for broken URIs. It might also be possible that a combination
6213 of normalizers that are safe by themselves results in unsafe transformations
6214 when improperly combined.
6215
6216 As an example the "percent-decode-unreserved" normalizer might result in
6217 unexpected results when a broken URI includes bare percent characters. One
6218 such a broken URI is "/%%36%36" which would be decoded to "/%66" which in
6219 turn is equivalent to "/f". By specifying the "strict" option requests to
6220 such a broken URI would safely be rejected.
6221
Tim Duesterhusb918a4a2021-04-16 23:52:29 +02006222 The following normalizers are available:
Tim Duesterhusd371e992021-04-15 21:45:58 +02006223
Tim Duesterhusdec1c362021-05-10 17:28:26 +02006224 - fragment-encode: Encodes "#" as "%23".
6225
6226 The "fragment-strip" normalizer should be preferred, unless it is known
6227 that broken clients do not correctly encode '#' within the path component.
6228
6229 Example:
6230 - /#foo -> /%23foo
6231
Tim Duesterhusc9e05ab2021-05-10 17:28:25 +02006232 - fragment-strip: Removes the URI's "fragment" component.
6233
6234 According to RFC 3986#3.5 the "fragment" component of an URI should not
6235 be sent, but handled by the User Agent after retrieving a resource.
6236
6237 This normalizer should be applied first to ensure that the fragment is
6238 not interpreted as part of the request's path component.
6239
6240 Example:
6241 - /#foo -> /
6242
Tim Duesterhusd6d33de2021-04-21 21:20:35 +02006243 - path-strip-dot: Removes "/./" segments within the "path" component
6244 (RFC 3986#6.2.2.3).
Maximilian Maderff3bb8b2021-04-21 00:22:50 +02006245
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006246 Segments including percent encoded dots ("%2E") will not be detected. Use
6247 the "percent-decode-unreserved" normalizer first if this is undesired.
6248
Tim Duesterhus7a95f412021-04-21 21:20:33 +02006249 Example:
6250 - /. -> /
6251 - /./bar/ -> /bar/
6252 - /a/./a -> /a/a
6253 - /.well-known/ -> /.well-known/ (no change)
Maximilian Maderff3bb8b2021-04-21 00:22:50 +02006254
Tim Duesterhusd6d33de2021-04-21 21:20:35 +02006255 - path-strip-dotdot: Normalizes "/../" segments within the "path" component
6256 (RFC 3986#6.2.2.3).
6257
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006258 This merges segments that attempt to access the parent directory with
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006259 their preceding segment.
6260
6261 Empty segments do not receive special treatment. Use the "merge-slashes"
6262 normalizer first if this is undesired.
6263
6264 Segments including percent encoded dots ("%2E") will not be detected. Use
6265 the "percent-decode-unreserved" normalizer first if this is undesired.
Tim Duesterhus9982fc22021-04-15 21:45:59 +02006266
6267 Example:
6268 - /foo/../ -> /
6269 - /foo/../bar/ -> /bar/
6270 - /foo/bar/../ -> /foo/
6271 - /../bar/ -> /../bar/
Tim Duesterhus560e1a62021-04-15 21:46:00 +02006272 - /bar/../../ -> /../
Tim Duesterhus9982fc22021-04-15 21:45:59 +02006273 - /foo//../ -> /foo/
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006274 - /foo/%2E%2E/ -> /foo/%2E%2E/
Tim Duesterhus9982fc22021-04-15 21:45:59 +02006275
Tim Duesterhus560e1a62021-04-15 21:46:00 +02006276 If the "full" option is specified then "../" at the beginning will be
6277 removed as well:
6278
6279 Example:
6280 - /../bar/ -> /bar/
6281 - /bar/../../ -> /
6282
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006283 - path-merge-slashes: Merges adjacent slashes within the "path" component
6284 into a single slash.
Tim Duesterhusd371e992021-04-15 21:45:58 +02006285
6286 Example:
6287 - // -> /
6288 - /foo//bar -> /foo/bar
6289
Tim Duesterhus2e4a18e2021-04-21 21:20:36 +02006290 - percent-decode-unreserved: Decodes unreserved percent encoded characters to
6291 their representation as a regular character (RFC 3986#6.2.2.2).
6292
6293 The set of unreserved characters includes all letters, all digits, "-",
6294 ".", "_", and "~".
6295
6296 Example:
6297 - /%61dmin -> /admin
6298 - /foo%3Fbar=baz -> /foo%3Fbar=baz (no change)
6299 - /%%36%36 -> /%66 (unsafe)
6300 - /%ZZ -> /%ZZ
6301
6302 If the "strict" option is specified then invalid sequences will result
6303 in a HTTP 400 Bad Request being returned.
6304
6305 Example:
6306 - /%%36%36 -> HTTP 400
6307 - /%ZZ -> HTTP 400
6308
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006309 - percent-to-uppercase: Uppercases letters within percent-encoded sequences
Tim Duesterhusc315efd2021-04-21 21:20:34 +02006310 (RFC 3986#6.2.2.1).
Tim Duesterhusa4071932021-04-15 21:46:02 +02006311
6312 Example:
6313 - /%6f -> /%6F
6314 - /%zz -> /%zz
6315
6316 If the "strict" option is specified then invalid sequences will result
6317 in a HTTP 400 Bad Request being returned.
6318
6319 Example:
6320 - /%zz -> HTTP 400
6321
Tim Duesterhus5be6ab22021-04-17 11:21:10 +02006322 - query-sort-by-name: Sorts the query string parameters by parameter name.
Tim Duesterhusd7b89be2021-04-15 21:46:01 +02006323 Parameters are assumed to be delimited by '&'. Shorter names sort before
6324 longer names and identical parameter names maintain their relative order.
6325
6326 Example:
6327 - /?c=3&a=1&b=2 -> /?a=1&b=2&c=3
6328 - /?aaa=3&a=1&aa=2 -> /?a=1&aa=2&aaa=3
6329 - /?a=3&b=4&a=1&b=5&a=2 -> /?a=3&a=1&a=2&b=4&b=5
6330
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006331http-request redirect <rule> [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006332
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006333 This performs an HTTP redirection based on a redirect rule. This is exactly
6334 the same as the "redirect" statement except that it inserts a redirect rule
6335 which can be processed in the middle of other "http-request" rules and that
6336 these rules use the "log-format" strings. See the "redirect" keyword for the
6337 rule's syntax.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006338
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006339http-request reject [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006340
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006341 This stops the evaluation of the rules and immediately closes the connection
6342 without sending any response. It acts similarly to the
6343 "tcp-request content reject" rules. It can be useful to force an immediate
6344 connection closure on HTTP/2 connections.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006345
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006346http-request replace-header <name> <match-regex> <replace-fmt>
6347 [ { if | unless } <condition> ]
Willy Tarreaua9083d02015-05-08 15:27:59 +02006348
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05006349 This matches the value of all occurrences of header field <name> against
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006350 <match-regex>. Matching is performed case-sensitively. Matching values are
6351 completely replaced by <replace-fmt>. Format characters are allowed in
6352 <replace-fmt> and work like <fmt> arguments in "http-request add-header".
6353 Standard back-references using the backslash ('\') followed by a number are
6354 supported.
Thierry FOURNIER82bf70d2015-05-26 17:58:29 +02006355
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006356 This action acts on whole header lines, regardless of the number of values
6357 they may contain. Thus it is well-suited to process headers naturally
6358 containing commas in their value, such as If-Modified-Since. Headers that
6359 contain a comma-separated list of values, such as Accept, should be processed
6360 using "http-request replace-value".
William Lallemand86d0df02017-11-24 21:36:45 +01006361
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006362 Example:
6363 http-request replace-header Cookie foo=([^;]*);(.*) foo=\1;ip=%bi;\2
6364
6365 # applied to:
6366 Cookie: foo=foobar; expires=Tue, 14-Jun-2016 01:40:45 GMT;
6367
6368 # outputs:
6369 Cookie: foo=foobar;ip=192.168.1.20; expires=Tue, 14-Jun-2016 01:40:45 GMT;
6370
6371 # assuming the backend IP is 192.168.1.20
Willy Tarreau09448f72014-06-25 18:12:15 +02006372
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006373 http-request replace-header User-Agent curl foo
6374
6375 # applied to:
6376 User-Agent: curl/7.47.0
Willy Tarreau09448f72014-06-25 18:12:15 +02006377
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006378 # outputs:
6379 User-Agent: foo
Willy Tarreau09448f72014-06-25 18:12:15 +02006380
Willy Tarreau262c3f12019-12-17 06:52:51 +01006381http-request replace-path <match-regex> <replace-fmt>
6382 [ { if | unless } <condition> ]
6383
6384 This works like "replace-header" except that it works on the request's path
6385 component instead of a header. The path component starts at the first '/'
Christopher Faulet82c83322020-09-02 14:16:59 +02006386 after an optional scheme+authority and ends before the question mark. Thus,
6387 the replacement does not modify the scheme, the authority and the
6388 query-string.
Willy Tarreau262c3f12019-12-17 06:52:51 +01006389
6390 It is worth noting that regular expressions may be more expensive to evaluate
6391 than certain ACLs, so rare replacements may benefit from a condition to avoid
6392 performing the evaluation at all if it does not match.
6393
6394 Example:
6395 # prefix /foo : turn /bar?q=1 into /foo/bar?q=1 :
6396 http-request replace-path (.*) /foo\1
6397
Willy Tarreau262c3f12019-12-17 06:52:51 +01006398 # strip /foo : turn /foo/bar?q=1 into /bar?q=1
6399 http-request replace-path /foo/(.*) /\1
6400 # or more efficient if only some requests match :
6401 http-request replace-path /foo/(.*) /\1 if { url_beg /foo/ }
6402
Christopher Faulet312294f2020-09-02 17:17:44 +02006403http-request replace-pathq <match-regex> <replace-fmt>
6404 [ { if | unless } <condition> ]
6405
6406 This does the same as "http-request replace-path" except that the path
6407 contains the query-string if any is present. Thus, the path and the
6408 query-string are replaced.
6409
6410 Example:
6411 # suffix /foo : turn /bar?q=1 into /bar/foo?q=1 :
6412 http-request replace-pathq ([^?]*)(\?(.*))? \1/foo\2
6413
Willy Tarreau33810222019-06-12 17:44:02 +02006414http-request replace-uri <match-regex> <replace-fmt>
6415 [ { if | unless } <condition> ]
6416
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006417 This works like "replace-header" except that it works on the request's URI part
6418 instead of a header. The URI part may contain an optional scheme, authority or
6419 query string. These are considered to be part of the value that is matched
6420 against.
6421
6422 It is worth noting that regular expressions may be more expensive to evaluate
6423 than certain ACLs, so rare replacements may benefit from a condition to avoid
6424 performing the evaluation at all if it does not match.
Willy Tarreau33810222019-06-12 17:44:02 +02006425
Willy Tarreau62b59132019-12-17 06:51:20 +01006426 IMPORTANT NOTE: historically in HTTP/1.x, the vast majority of requests sent
6427 by browsers use the "origin form", which differs from the "absolute form" in
6428 that they do not contain a scheme nor authority in the URI portion. Mostly
6429 only requests sent to proxies, those forged by hand and some emitted by
6430 certain applications use the absolute form. As such, "replace-uri" usually
6431 works fine most of the time in HTTP/1.x with rules starting with a "/". But
6432 with HTTP/2, clients are encouraged to send absolute URIs only, which look
6433 like the ones HTTP/1 clients use to talk to proxies. Such partial replace-uri
6434 rules may then fail in HTTP/2 when they work in HTTP/1. Either the rules need
Willy Tarreau262c3f12019-12-17 06:52:51 +01006435 to be adapted to optionally match a scheme and authority, or replace-path
6436 should be used.
Willy Tarreau33810222019-06-12 17:44:02 +02006437
Willy Tarreau62b59132019-12-17 06:51:20 +01006438 Example:
6439 # rewrite all "http" absolute requests to "https":
6440 http-request replace-uri ^http://(.*) https://\1
Willy Tarreau33810222019-06-12 17:44:02 +02006441
Willy Tarreau62b59132019-12-17 06:51:20 +01006442 # prefix /foo : turn /bar?q=1 into /foo/bar?q=1 :
6443 http-request replace-uri ([^/:]*://[^/]*)?(.*) \1/foo\2
Willy Tarreau33810222019-06-12 17:44:02 +02006444
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006445http-request replace-value <name> <match-regex> <replace-fmt>
6446 [ { if | unless } <condition> ]
Willy Tarreau09448f72014-06-25 18:12:15 +02006447
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006448 This works like "replace-header" except that it matches the regex against
6449 every comma-delimited value of the header field <name> instead of the
6450 entire header. This is suited for all headers which are allowed to carry
6451 more than one value. An example could be the Accept header.
Willy Tarreau09448f72014-06-25 18:12:15 +02006452
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006453 Example:
6454 http-request replace-value X-Forwarded-For ^192\.168\.(.*)$ 172.16.\1
Thierry FOURNIER236657b2015-08-19 08:25:14 +02006455
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006456 # applied to:
6457 X-Forwarded-For: 192.168.10.1, 192.168.13.24, 10.0.0.37
Thierry FOURNIERe0627bd2015-08-04 08:20:33 +02006458
Tim Duesterhus2252beb2019-10-29 00:05:13 +01006459 # outputs:
6460 X-Forwarded-For: 172.16.10.1, 172.16.13.24, 10.0.0.37
Frédéric Lécaille6778b272018-01-29 15:22:53 +01006461
Christopher Faulet24231ab2020-01-24 17:44:23 +01006462http-request return [status <code>] [content-type <type>]
6463 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
6464 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
Christopher Faulet4a2c1422020-01-31 17:36:01 +01006465 [ hdr <name> <fmt> ]*
Christopher Faulet24231ab2020-01-24 17:44:23 +01006466 [ { if | unless } <condition> ]
6467
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05006468 This stops the evaluation of the rules and immediately returns a response. The
Christopher Faulet24231ab2020-01-24 17:44:23 +01006469 default status code used for the response is 200. It can be optionally
6470 specified as an arguments to "status". The response content-type may also be
Daniel Corbett67a82712020-07-06 23:01:19 -04006471 specified as an argument to "content-type". Finally the response itself may
Sébastien Grossab877122020-10-08 10:06:03 +02006472 be defined. It can be a full HTTP response specifying the errorfile to use,
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05006473 or the response payload specifying the file or the string to use. These rules
Christopher Faulet24231ab2020-01-24 17:44:23 +01006474 are followed to create the response :
6475
6476 * If neither the errorfile nor the payload to use is defined, a dummy
6477 response is returned. Only the "status" argument is considered. It can be
6478 any code in the range [200, 599]. The "content-type" argument, if any, is
6479 ignored.
6480
6481 * If "default-errorfiles" argument is set, the proxy's errorfiles are
6482 considered. If the "status" argument is defined, it must be one of the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04006483 status code handled by HAProxy (200, 400, 403, 404, 405, 408, 410, 413,
Christopher Faulete095f312020-12-07 11:22:24 +01006484 425, 429, 500, 501, 502, 503, and 504). The "content-type" argument, if
6485 any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01006486
6487 * If a specific errorfile is defined, with an "errorfile" argument, the
6488 corresponding file, containing a full HTTP response, is returned. Only the
6489 "status" argument is considered. It must be one of the status code handled
Daniel Corbett9f0843f2021-05-08 10:50:37 -04006490 by HAProxy (200, 400, 403, 404, 405, 408, 410, 413, 425, 429, 500, 501,
Christopher Faulete095f312020-12-07 11:22:24 +01006491 502, 503, and 504). The "content-type" argument, if any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01006492
6493 * If an http-errors section is defined, with an "errorfiles" argument, the
6494 corresponding file in the specified http-errors section, containing a full
6495 HTTP response, is returned. Only the "status" argument is considered. It
Daniel Corbett9f0843f2021-05-08 10:50:37 -04006496 must be one of the status code handled by HAProxy (200, 400, 403, 404, 405,
Christopher Faulete095f312020-12-07 11:22:24 +01006497 408, 410, 413, 425, 429, 500, 501, 502, 503, and 504). The "content-type"
Anthonin Bonnefoy85048f82020-06-22 09:17:01 +02006498 argument, if any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01006499
6500 * If a "file" or a "lf-file" argument is specified, the file's content is
6501 used as the response payload. If the file is not empty, its content-type
6502 must be set as argument to "content-type". Otherwise, any "content-type"
6503 argument is ignored. With a "lf-file" argument, the file's content is
6504 evaluated as a log-format string. With a "file" argument, it is considered
6505 as a raw content.
6506
6507 * If a "string" or "lf-string" argument is specified, the defined string is
6508 used as the response payload. The content-type must always be set as
6509 argument to "content-type". With a "lf-string" argument, the string is
6510 evaluated as a log-format string. With a "string" argument, it is
6511 considered as a raw string.
6512
Sébastien Grossab877122020-10-08 10:06:03 +02006513 When the response is not based on an errorfile, it is possible to append HTTP
Christopher Faulet4a2c1422020-01-31 17:36:01 +01006514 header fields to the response using "hdr" arguments. Otherwise, all "hdr"
6515 arguments are ignored. For each one, the header name is specified in <name>
6516 and its value is defined by <fmt> which follows the log-format rules.
6517
Christopher Faulet24231ab2020-01-24 17:44:23 +01006518 Note that the generated response must be smaller than a buffer. And to avoid
6519 any warning, when an errorfile or a raw file is loaded, the buffer space
Sébastien Grossab877122020-10-08 10:06:03 +02006520 reserved for the headers rewriting should also be free.
Christopher Faulet24231ab2020-01-24 17:44:23 +01006521
6522 No further "http-request" rules are evaluated.
6523
6524 Example:
Daniel Corbett67a82712020-07-06 23:01:19 -04006525 http-request return errorfile /etc/haproxy/errorfiles/200.http \
Christopher Faulet24231ab2020-01-24 17:44:23 +01006526 if { path /ping }
6527
6528 http-request return content-type image/x-icon file /var/www/favicon.ico \
6529 if { path /favicon.ico }
6530
6531 http-request return status 403 content-type text/plain \
6532 lf-string "Access denied. IP %[src] is blacklisted." \
6533 if { src -f /etc/haproxy/blacklist.lst }
6534
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006535http-request sc-inc-gpc0(<sc-id>) [ { if | unless } <condition> ]
6536http-request sc-inc-gpc1(<sc-id>) [ { if | unless } <condition> ]
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02006537
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006538 This actions increments the GPC0 or GPC1 counter according with the sticky
6539 counter designated by <sc-id>. If an error occurs, this action silently fails
6540 and the actions evaluation continues.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02006541
Cédric Dufour0d7712d2019-11-06 18:38:53 +01006542http-request sc-set-gpt0(<sc-id>) { <int> | <expr> }
6543 [ { if | unless } <condition> ]
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02006544
Cédric Dufour0d7712d2019-11-06 18:38:53 +01006545 This action sets the 32-bit unsigned GPT0 tag according to the sticky counter
6546 designated by <sc-id> and the value of <int>/<expr>. The expected result is a
6547 boolean. If an error occurs, this action silently fails and the actions
6548 evaluation continues.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02006549
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006550http-request set-dst <expr> [ { if | unless } <condition> ]
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02006551
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006552 This is used to set the destination IP address to the value of specified
6553 expression. Useful when a proxy in front of HAProxy rewrites destination IP,
6554 but provides the correct IP in a HTTP header; or you want to mask the IP for
6555 privacy. If you want to connect to the new address/port, use '0.0.0.0:0' as a
6556 server address in the backend.
Christopher Faulet85d79c92016-11-09 16:54:56 +01006557
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006558 Arguments:
6559 <expr> Is a standard HAProxy expression formed by a sample-fetch followed
6560 by some converters.
Christopher Faulet85d79c92016-11-09 16:54:56 +01006561
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006562 Example:
6563 http-request set-dst hdr(x-dst)
6564 http-request set-dst dst,ipmask(24)
Christopher Faulet85d79c92016-11-09 16:54:56 +01006565
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006566 When possible, set-dst preserves the original destination port as long as the
6567 address family allows it, otherwise the destination port is set to 0.
Adis Nezirovic2fbcafc2015-07-06 15:44:30 +02006568
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006569http-request set-dst-port <expr> [ { if | unless } <condition> ]
Adis Nezirovic2fbcafc2015-07-06 15:44:30 +02006570
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006571 This is used to set the destination port address to the value of specified
6572 expression. If you want to connect to the new address/port, use '0.0.0.0:0'
6573 as a server address in the backend.
Adis Nezirovic2fbcafc2015-07-06 15:44:30 +02006574
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006575 Arguments:
6576 <expr> Is a standard HAProxy expression formed by a sample-fetch
6577 followed by some converters.
Adis Nezirovic2fbcafc2015-07-06 15:44:30 +02006578
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006579 Example:
6580 http-request set-dst-port hdr(x-port)
6581 http-request set-dst-port int(4000)
Adis Nezirovic2fbcafc2015-07-06 15:44:30 +02006582
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006583 When possible, set-dst-port preserves the original destination address as
6584 long as the address family supports a port, otherwise it forces the
6585 destination address to IPv4 "0.0.0.0" before rewriting the port.
William Lallemand44be6402016-05-25 01:51:35 +02006586
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006587http-request set-header <name> <fmt> [ { if | unless } <condition> ]
William Lallemand44be6402016-05-25 01:51:35 +02006588
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006589 This does the same as "http-request add-header" except that the header name
6590 is first removed if it existed. This is useful when passing security
6591 information to the server, where the header must not be manipulated by
6592 external users. Note that the new value is computed before the removal so it
6593 is possible to concatenate a value to an existing header.
William Lallemand44be6402016-05-25 01:51:35 +02006594
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006595 Example:
6596 http-request set-header X-Haproxy-Current-Date %T
6597 http-request set-header X-SSL %[ssl_fc]
6598 http-request set-header X-SSL-Session_ID %[ssl_fc_session_id,hex]
6599 http-request set-header X-SSL-Client-Verify %[ssl_c_verify]
6600 http-request set-header X-SSL-Client-DN %{+Q}[ssl_c_s_dn]
6601 http-request set-header X-SSL-Client-CN %{+Q}[ssl_c_s_dn(cn)]
6602 http-request set-header X-SSL-Issuer %{+Q}[ssl_c_i_dn]
6603 http-request set-header X-SSL-Client-NotBefore %{+Q}[ssl_c_notbefore]
6604 http-request set-header X-SSL-Client-NotAfter %{+Q}[ssl_c_notafter]
William Lallemand44be6402016-05-25 01:51:35 +02006605
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006606http-request set-log-level <level> [ { if | unless } <condition> ]
William Lallemand44be6402016-05-25 01:51:35 +02006607
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006608 This is used to change the log level of the current request when a certain
6609 condition is met. Valid levels are the 8 syslog levels (see the "log"
6610 keyword) plus the special level "silent" which disables logging for this
6611 request. This rule is not final so the last matching rule wins. This rule
6612 can be useful to disable health checks coming from another equipment.
William Lallemand13e9b0c2016-05-25 02:34:07 +02006613
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006614http-request set-map(<file-name>) <key fmt> <value fmt>
6615 [ { if | unless } <condition> ]
William Lallemand13e9b0c2016-05-25 02:34:07 +02006616
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006617 This is used to add a new entry into a MAP. The MAP must be loaded from a
6618 file (even a dummy empty file). The file name of the MAP to be updated is
6619 passed between parentheses. It takes 2 arguments: <key fmt>, which follows
6620 log-format rules, used to collect MAP key, and <value fmt>, which follows
6621 log-format rules, used to collect content for the new entry.
6622 It performs a lookup in the MAP before insertion, to avoid duplicated (or
6623 more) values. This lookup is done by a linear search and can be expensive
6624 with large lists! It is the equivalent of the "set map" command from the
6625 stats socket, but can be triggered by an HTTP request.
William Lallemand13e9b0c2016-05-25 02:34:07 +02006626
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006627http-request set-mark <mark> [ { if | unless } <condition> ]
William Lallemand13e9b0c2016-05-25 02:34:07 +02006628
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006629 This is used to set the Netfilter MARK on all packets sent to the client to
6630 the value passed in <mark> on platforms which support it. This value is an
6631 unsigned 32 bit value which can be matched by netfilter and by the routing
6632 table. It can be expressed both in decimal or hexadecimal format (prefixed by
6633 "0x"). This can be useful to force certain packets to take a different route
6634 (for example a cheaper network path for bulk downloads). This works on Linux
6635 kernels 2.6.32 and above and requires admin privileges.
Willy Tarreau00005ce2016-10-21 15:07:45 +02006636
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006637http-request set-method <fmt> [ { if | unless } <condition> ]
William Lallemand13e9b0c2016-05-25 02:34:07 +02006638
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006639 This rewrites the request method with the result of the evaluation of format
6640 string <fmt>. There should be very few valid reasons for having to do so as
6641 this is more likely to break something than to fix it.
William Lallemand13e9b0c2016-05-25 02:34:07 +02006642
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006643http-request set-nice <nice> [ { if | unless } <condition> ]
William Lallemand13e9b0c2016-05-25 02:34:07 +02006644
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006645 This sets the "nice" factor of the current request being processed. It only
6646 has effect against the other requests being processed at the same time.
6647 The default value is 0, unless altered by the "nice" setting on the "bind"
6648 line. The accepted range is -1024..1024. The higher the value, the nicest
6649 the request will be. Lower values will make the request more important than
6650 other ones. This can be useful to improve the speed of some requests, or
6651 lower the priority of non-important requests. Using this setting without
6652 prior experimentation can cause some major slowdown.
William Lallemand13e9b0c2016-05-25 02:34:07 +02006653
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006654http-request set-path <fmt> [ { if | unless } <condition> ]
Willy Tarreau00005ce2016-10-21 15:07:45 +02006655
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006656 This rewrites the request path with the result of the evaluation of format
6657 string <fmt>. The query string, if any, is left intact. If a scheme and
6658 authority is found before the path, they are left intact as well. If the
6659 request doesn't have a path ("*"), this one is replaced with the format.
6660 This can be used to prepend a directory component in front of a path for
6661 example. See also "http-request set-query" and "http-request set-uri".
Willy Tarreau2d392c22015-08-24 01:43:45 +02006662
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006663 Example :
6664 # prepend the host name before the path
6665 http-request set-path /%[hdr(host)]%[path]
Christopher Faulet76c09ef2017-09-21 11:03:52 +02006666
Christopher Faulet312294f2020-09-02 17:17:44 +02006667http-request set-pathq <fmt> [ { if | unless } <condition> ]
6668
6669 This does the same as "http-request set-path" except that the query-string is
6670 also rewritten. It may be used to remove the query-string, including the
6671 question mark (it is not possible using "http-request set-query").
6672
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006673http-request set-priority-class <expr> [ { if | unless } <condition> ]
Olivier Houchardccaa7de2017-10-02 11:51:03 +02006674
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006675 This is used to set the queue priority class of the current request.
6676 The value must be a sample expression which converts to an integer in the
6677 range -2047..2047. Results outside this range will be truncated.
6678 The priority class determines the order in which queued requests are
6679 processed. Lower values have higher priority.
Christopher Faulet76c09ef2017-09-21 11:03:52 +02006680
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006681http-request set-priority-offset <expr> [ { if | unless } <condition> ]
Christopher Faulet76c09ef2017-09-21 11:03:52 +02006682
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006683 This is used to set the queue priority timestamp offset of the current
6684 request. The value must be a sample expression which converts to an integer
6685 in the range -524287..524287. Results outside this range will be truncated.
6686 When a request is queued, it is ordered first by the priority class, then by
6687 the current timestamp adjusted by the given offset in milliseconds. Lower
6688 values have higher priority.
6689 Note that the resulting timestamp is is only tracked with enough precision
6690 for 524,287ms (8m44s287ms). If the request is queued long enough to where the
6691 adjusted timestamp exceeds this value, it will be misidentified as highest
6692 priority. Thus it is important to set "timeout queue" to a value, where when
6693 combined with the offset, does not exceed this limit.
Christopher Faulet76c09ef2017-09-21 11:03:52 +02006694
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006695http-request set-query <fmt> [ { if | unless } <condition> ]
Willy Tarreau20b0de52012-12-24 15:45:22 +01006696
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006697 This rewrites the request's query string which appears after the first
6698 question mark ("?") with the result of the evaluation of format string <fmt>.
6699 The part prior to the question mark is left intact. If the request doesn't
6700 contain a question mark and the new value is not empty, then one is added at
6701 the end of the URI, followed by the new value. If a question mark was
6702 present, it will never be removed even if the value is empty. This can be
6703 used to add or remove parameters from the query string.
Ruoshan Huangeb5a3632015-12-08 21:00:23 +08006704
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006705 See also "http-request set-query" and "http-request set-uri".
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01006706
6707 Example:
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006708 # replace "%3D" with "=" in the query string
6709 http-request set-query %[query,regsub(%3D,=,g)]
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01006710
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006711http-request set-src <expr> [ { if | unless } <condition> ]
6712 This is used to set the source IP address to the value of specified
6713 expression. Useful when a proxy in front of HAProxy rewrites source IP, but
6714 provides the correct IP in a HTTP header; or you want to mask source IP for
Olivier Doucet56e31202020-04-21 09:32:56 +02006715 privacy. All subsequent calls to "src" fetch will return this value
6716 (see example).
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006717
6718 Arguments :
6719 <expr> Is a standard HAProxy expression formed by a sample-fetch followed
6720 by some converters.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01006721
Olivier Doucet56e31202020-04-21 09:32:56 +02006722 See also "option forwardfor".
6723
Cyril Bonté78caf842010-03-10 22:41:43 +01006724 Example:
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006725 http-request set-src hdr(x-forwarded-for)
6726 http-request set-src src,ipmask(24)
6727
Olivier Doucet56e31202020-04-21 09:32:56 +02006728 # After the masking this will track connections
6729 # based on the IP address with the last byte zeroed out.
6730 http-request track-sc0 src
6731
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006732 When possible, set-src preserves the original source port as long as the
6733 address family allows it, otherwise the source port is set to 0.
6734
6735http-request set-src-port <expr> [ { if | unless } <condition> ]
6736
6737 This is used to set the source port address to the value of specified
6738 expression.
6739
6740 Arguments:
6741 <expr> Is a standard HAProxy expression formed by a sample-fetch followed
6742 by some converters.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +01006743
Willy Tarreau20b0de52012-12-24 15:45:22 +01006744 Example:
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006745 http-request set-src-port hdr(x-port)
6746 http-request set-src-port int(4000)
6747
6748 When possible, set-src-port preserves the original source address as long as
6749 the address family supports a port, otherwise it forces the source address to
6750 IPv4 "0.0.0.0" before rewriting the port.
6751
Alex59c53352021-04-27 12:57:07 +02006752http-request set-timeout { server | tunnel } { <timeout> | <expr> }
Amaury Denoyelle8d228232020-12-10 13:43:54 +01006753 [ { if | unless } <condition> ]
6754
6755 This action overrides the specified "server" or "tunnel" timeout for the
6756 current stream only. The timeout can be specified in millisecond or with any
6757 other unit if the number is suffixed by the unit as explained at the top of
6758 this document. It is also possible to write an expression which must returns
6759 a number interpreted as a timeout in millisecond.
6760
6761 Note that the server/tunnel timeouts are only relevant on the backend side
6762 and thus this rule is only available for the proxies with backend
6763 capabilities. Also the timeout value must be non-null to obtain the expected
6764 results.
6765
6766 Example:
Alex59c53352021-04-27 12:57:07 +02006767 http-request set-timeout tunnel 5s
6768 http-request set-timeout server req.hdr(host),map_int(host.lst)
Amaury Denoyelle8d228232020-12-10 13:43:54 +01006769
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006770http-request set-tos <tos> [ { if | unless } <condition> ]
6771
6772 This is used to set the TOS or DSCP field value of packets sent to the client
6773 to the value passed in <tos> on platforms which support this. This value
6774 represents the whole 8 bits of the IP TOS field, and can be expressed both in
6775 decimal or hexadecimal format (prefixed by "0x"). Note that only the 6 higher
6776 bits are used in DSCP or TOS, and the two lower bits are always 0. This can
6777 be used to adjust some routing behavior on border routers based on some
6778 information from the request.
6779
6780 See RFC 2474, 2597, 3260 and 4594 for more information.
6781
6782http-request set-uri <fmt> [ { if | unless } <condition> ]
6783
6784 This rewrites the request URI with the result of the evaluation of format
6785 string <fmt>. The scheme, authority, path and query string are all replaced
6786 at once. This can be used to rewrite hosts in front of proxies, or to
6787 perform complex modifications to the URI such as moving parts between the
6788 path and the query string.
6789 See also "http-request set-path" and "http-request set-query".
6790
6791http-request set-var(<var-name>) <expr> [ { if | unless } <condition> ]
6792
6793 This is used to set the contents of a variable. The variable is declared
6794 inline.
6795
6796 Arguments:
6797 <var-name> The name of the variable starts with an indication about its
6798 scope. The scopes allowed are:
6799 "proc" : the variable is shared with the whole process
6800 "sess" : the variable is shared with the whole session
6801 "txn" : the variable is shared with the transaction
6802 (request and response)
6803 "req" : the variable is shared only during request
6804 processing
6805 "res" : the variable is shared only during response
6806 processing
6807 This prefix is followed by a name. The separator is a '.'.
6808 The name may only contain characters 'a-z', 'A-Z', '0-9'
6809 and '_'.
6810
6811 <expr> Is a standard HAProxy expression formed by a sample-fetch
6812 followed by some converters.
Willy Tarreau20b0de52012-12-24 15:45:22 +01006813
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006814 Example:
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006815 http-request set-var(req.my_var) req.fhdr(user-agent),lower
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006816
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006817http-request send-spoe-group <engine-name> <group-name>
6818 [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006819
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006820 This action is used to trigger sending of a group of SPOE messages. To do so,
6821 the SPOE engine used to send messages must be defined, as well as the SPOE
6822 group to send. Of course, the SPOE engine must refer to an existing SPOE
6823 filter. If not engine name is provided on the SPOE filter line, the SPOE
6824 agent name must be used.
6825
6826 Arguments:
6827 <engine-name> The SPOE engine name.
6828
6829 <group-name> The SPOE group name as specified in the engine
6830 configuration.
6831
6832http-request silent-drop [ { if | unless } <condition> ]
6833
6834 This stops the evaluation of the rules and makes the client-facing connection
6835 suddenly disappear using a system-dependent way that tries to prevent the
6836 client from being notified. The effect it then that the client still sees an
6837 established connection while there's none on HAProxy. The purpose is to
6838 achieve a comparable effect to "tarpit" except that it doesn't use any local
6839 resource at all on the machine running HAProxy. It can resist much higher
6840 loads than "tarpit", and slow down stronger attackers. It is important to
6841 understand the impact of using this mechanism. All stateful equipment placed
6842 between the client and HAProxy (firewalls, proxies, load balancers) will also
6843 keep the established connection for a long time and may suffer from this
6844 action.
6845 On modern Linux systems running with enough privileges, the TCP_REPAIR socket
6846 option is used to block the emission of a TCP reset. On other systems, the
6847 socket's TTL is reduced to 1 so that the TCP reset doesn't pass the first
6848 router, though it's still delivered to local networks. Do not use it unless
6849 you fully understand how it works.
6850
Christopher Faulet46f95542019-12-20 10:07:22 +01006851http-request strict-mode { on | off }
6852
6853 This enables or disables the strict rewriting mode for following rules. It
6854 does not affect rules declared before it and it is only applicable on rules
6855 performing a rewrite on the requests. When the strict mode is enabled, any
6856 rewrite failure triggers an internal error. Otherwise, such errors are
6857 silently ignored. The purpose of the strict rewriting mode is to make some
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05006858 rewrites optional while others must be performed to continue the request
Christopher Faulet46f95542019-12-20 10:07:22 +01006859 processing.
6860
Christopher Faulet1aea50e2020-01-17 16:03:53 +01006861 By default, the strict rewriting mode is enabled. Its value is also reset
Christopher Faulet46f95542019-12-20 10:07:22 +01006862 when a ruleset evaluation ends. So, for instance, if you change the mode on
6863 the frontend, the default mode is restored when HAProxy starts the backend
6864 rules evaluation.
6865
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006866http-request tarpit [deny_status <status>] [ { if | unless } <condition> ]
6867http-request tarpit [ { status | deny_status } <code>] [content-type <type>]
6868 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
6869 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
6870 [ hdr <name> <fmt> ]*
6871 [ { if | unless } <condition> ]
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006872
6873 This stops the evaluation of the rules and immediately blocks the request
6874 without responding for a delay specified by "timeout tarpit" or
6875 "timeout connect" if the former is not set. After that delay, if the client
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006876 is still connected, a response is returned so that the client does not
6877 suspect it has been tarpitted. Logs will report the flags "PT". The goal of
6878 the tarpit rule is to slow down robots during an attack when they're limited
6879 on the number of concurrent requests. It can be very efficient against very
6880 dumb robots, and will significantly reduce the load on firewalls compared to
6881 a "deny" rule. But when facing "correctly" developed robots, it can make
Daniel Corbett9f0843f2021-05-08 10:50:37 -04006882 things worse by forcing HAProxy and the front firewall to support insane
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006883 number of concurrent connections. By default an HTTP error 500 is returned.
6884 But the response may be customized using same syntax than
6885 "http-request return" rules. Thus, see "http-request return" for details.
Ilya Shipitsin11057a32020-06-21 21:18:27 +05006886 For compatibility purpose, when no argument is defined, or only "deny_status",
Christopher Faulet5cb513a2020-05-13 17:56:56 +02006887 the argument "default-errorfiles" is implied. It means
6888 "http-request tarpit [deny_status <status>]" is an alias of
6889 "http-request tarpit [status <status>] default-errorfiles".
6890 No further "http-request" rules are evaluated.
6891 See also "http-request return" and "http-request silent-drop".
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006892
6893http-request track-sc0 <key> [table <table>] [ { if | unless } <condition> ]
6894http-request track-sc1 <key> [table <table>] [ { if | unless } <condition> ]
6895http-request track-sc2 <key> [table <table>] [ { if | unless } <condition> ]
6896
6897 This enables tracking of sticky counters from current request. These rules do
6898 not stop evaluation and do not change default action. The number of counters
6899 that may be simultaneously tracked by the same connection is set in
6900 MAX_SESS_STKCTR at build time (reported in haproxy -vv) which defaults to 3,
Matteo Contrini1857b8c2020-10-16 17:35:54 +02006901 so the track-sc number is between 0 and (MAX_SESS_STKCTR-1). The first
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006902 "track-sc0" rule executed enables tracking of the counters of the specified
6903 table as the first set. The first "track-sc1" rule executed enables tracking
6904 of the counters of the specified table as the second set. The first
6905 "track-sc2" rule executed enables tracking of the counters of the specified
6906 table as the third set. It is a recommended practice to use the first set of
6907 counters for the per-frontend counters and the second set for the per-backend
6908 ones. But this is just a guideline, all may be used everywhere.
6909
6910 Arguments :
6911 <key> is mandatory, and is a sample expression rule as described in
6912 section 7.3. It describes what elements of the incoming request or
6913 connection will be analyzed, extracted, combined, and used to
6914 select which table entry to update the counters.
6915
6916 <table> is an optional table to be used instead of the default one, which
6917 is the stick-table declared in the current proxy. All the counters
6918 for the matches and updates for the key will then be performed in
6919 that table until the session ends.
6920
6921 Once a "track-sc*" rule is executed, the key is looked up in the table and if
6922 it is not found, an entry is allocated for it. Then a pointer to that entry
6923 is kept during all the session's life, and this entry's counters are updated
6924 as often as possible, every time the session's counters are updated, and also
6925 systematically when the session ends. Counters are only updated for events
6926 that happen after the tracking has been started. As an exception, connection
6927 counters and request counters are systematically updated so that they reflect
6928 useful information.
6929
6930 If the entry tracks concurrent connection counters, one connection is counted
6931 for as long as the entry is tracked, and the entry will not expire during
6932 that time. Tracking counters also provides a performance advantage over just
6933 checking the keys, because only one table lookup is performed for all ACL
6934 checks that make use of it.
6935
6936http-request unset-var(<var-name>) [ { if | unless } <condition> ]
6937
6938 This is used to unset a variable. See above for details about <var-name>.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006939
6940 Example:
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006941 http-request unset-var(req.my_var)
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006942
Christopher Faulet579d83b2019-11-22 15:34:17 +01006943http-request use-service <service-name> [ { if | unless } <condition> ]
6944
6945 This directive executes the configured HTTP service to reply to the request
6946 and stops the evaluation of the rules. An HTTP service may choose to reply by
6947 sending any valid HTTP response or it may immediately close the connection
6948 without sending any response. Outside natives services, for instance the
6949 Prometheus exporter, it is possible to write your own services in Lua. No
6950 further "http-request" rules are evaluated.
6951
6952 Arguments :
6953 <service-name> is mandatory. It is the service to call
6954
6955 Example:
6956 http-request use-service prometheus-exporter if { path /metrics }
6957
Christopher Faulet021a8e42021-03-29 10:46:38 +02006958http-request wait-for-body time <time> [ at-least <bytes> ]
6959 [ { if | unless } <condition> ]
6960
6961 This will delay the processing of the request waiting for the payload for at
6962 most <time> milliseconds. if "at-least" argument is specified, HAProxy stops
6963 to wait the payload when the first <bytes> bytes are received. 0 means no
6964 limit, it is the default value. Regardless the "at-least" argument value,
6965 HAProxy stops to wait if the whole payload is received or if the request
6966 buffer is full. This action may be used as a replacement to "option
6967 http-buffer-request".
6968
6969 Arguments :
6970
6971 <time> is mandatory. It is the maximum time to wait for the body. It
6972 follows the HAProxy time format and is expressed in milliseconds.
6973
6974 <bytes> is optional. It is the minimum payload size to receive to stop to
Ilya Shipitsinb2be9a12021-04-24 13:25:42 +05006975 wait. It follows the HAProxy size format and is expressed in
Christopher Faulet021a8e42021-03-29 10:46:38 +02006976 bytes.
6977
6978 Example:
6979 http-request wait-for-body time 1s at-least 1k if METH_POST
6980
6981 See also : "option http-buffer-request"
6982
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006983http-request wait-for-handshake [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006984
Cyril Bontéc6ad23b2018-10-17 00:14:50 +02006985 This will delay the processing of the request until the SSL handshake
6986 happened. This is mostly useful to delay processing early data until we're
6987 sure they are valid.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02006988
Willy Tarreauef781042010-01-27 11:53:01 +01006989
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02006990http-response <action> <options...> [ { if | unless } <condition> ]
Willy Tarreaue365c0b2013-06-11 16:06:12 +02006991 Access control for Layer 7 responses
6992
6993 May be used in sections: defaults | frontend | listen | backend
6994 no | yes | yes | yes
6995
6996 The http-response statement defines a set of rules which apply to layer 7
6997 processing. The rules are evaluated in their declaration order when they are
6998 met in a frontend, listen or backend section. Any rule may optionally be
6999 followed by an ACL-based condition, in which case it will only be evaluated
7000 if the condition is true. Since these rules apply on responses, the backend
7001 rules are applied first, followed by the frontend's rules.
7002
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007003 The first keyword is the rule's action. The supported actions are described
7004 below.
Willy Tarreaue365c0b2013-06-11 16:06:12 +02007005
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007006 There is no limit to the number of http-response statements per instance.
Willy Tarreaue365c0b2013-06-11 16:06:12 +02007007
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007008 Example:
7009 acl key_acl res.hdr(X-Acl-Key) -m found
Thierry FOURNIERdad3d1d2014-04-22 18:07:25 +02007010
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007011 acl myhost hdr(Host) -f myhost.lst
Sasha Pachev218f0642014-06-16 12:05:59 -06007012
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007013 http-response add-acl(myhost.lst) %[res.hdr(X-Acl-Key)] if key_acl
7014 http-response del-acl(myhost.lst) %[res.hdr(X-Acl-Key)] if key_acl
Sasha Pachev218f0642014-06-16 12:05:59 -06007015
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007016 Example:
7017 acl value res.hdr(X-Value) -m found
Sasha Pachev218f0642014-06-16 12:05:59 -06007018
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007019 use_backend bk_appli if { hdr(Host),map_str(map.lst) -m found }
Sasha Pachev218f0642014-06-16 12:05:59 -06007020
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007021 http-response set-map(map.lst) %[src] %[res.hdr(X-Value)] if value
7022 http-response del-map(map.lst) %[src] if ! value
Sasha Pachev218f0642014-06-16 12:05:59 -06007023
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007024 See also : "http-request", section 3.4 about userlists and section 7 about
7025 ACL usage.
Sasha Pachev218f0642014-06-16 12:05:59 -06007026
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007027http-response add-acl(<file-name>) <key fmt> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06007028
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007029 This is used to add a new entry into an ACL. The ACL must be loaded from a
7030 file (even a dummy empty file). The file name of the ACL to be updated is
7031 passed between parentheses. It takes one argument: <key fmt>, which follows
7032 log-format rules, to collect content of the new entry. It performs a lookup
7033 in the ACL before insertion, to avoid duplicated (or more) values.
7034 This lookup is done by a linear search and can be expensive with large lists!
7035 It is the equivalent of the "add acl" command from the stats socket, but can
7036 be triggered by an HTTP response.
Sasha Pachev218f0642014-06-16 12:05:59 -06007037
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007038http-response add-header <name> <fmt> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06007039
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007040 This appends an HTTP header field whose name is specified in <name> and whose
7041 value is defined by <fmt> which follows the log-format rules (see Custom Log
7042 Format in section 8.2.4). This may be used to send a cookie to a client for
7043 example, or to pass some internal information.
7044 This rule is not final, so it is possible to add other similar rules.
7045 Note that header addition is performed immediately, so one rule might reuse
7046 the resulting header from a previous rule.
Sasha Pachev218f0642014-06-16 12:05:59 -06007047
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007048http-response allow [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06007049
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007050 This stops the evaluation of the rules and lets the response pass the check.
7051 No further "http-response" rules are evaluated for the current section.
Sasha Pachev218f0642014-06-16 12:05:59 -06007052
Jarno Huuskonen251a6b72019-01-04 14:05:02 +02007053http-response cache-store <name> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06007054
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02007055 See section 6.2 about cache setup.
Sasha Pachev218f0642014-06-16 12:05:59 -06007056
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007057http-response capture <sample> id <id> [ { if | unless } <condition> ]
Sasha Pachev218f0642014-06-16 12:05:59 -06007058
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007059 This captures sample expression <sample> from the response buffer, and
7060 converts it to a string. The resulting string is stored into the next request
7061 "capture" slot, so it will possibly appear next to some captured HTTP
7062 headers. It will then automatically appear in the logs, and it will be
7063 possible to extract it using sample fetch rules to feed it into headers or
7064 anything. Please check section 7.3 (Fetching samples) and
7065 "capture response header" for more information.
Thierry FOURNIER35d70ef2015-08-26 16:21:56 +02007066
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007067 The keyword "id" is the id of the capture slot which is used for storing the
7068 string. The capture slot must be defined in an associated frontend.
7069 This is useful to run captures in backends. The slot id can be declared by a
7070 previous directive "http-response capture" or with the "declare capture"
7071 keyword.
Baptiste Assmann19a69b32020-01-16 14:34:22 +01007072
7073 When using this action in a backend, double check that the relevant
7074 frontend(s) have the required capture slots otherwise, this rule will be
7075 ignored at run time. This can't be detected at configuration parsing time
7076 due to HAProxy's ability to dynamically resolve backend name at runtime.
Thierry FOURNIER35d70ef2015-08-26 16:21:56 +02007077
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007078http-response del-acl(<file-name>) <key fmt> [ { if | unless } <condition> ]
Thierry FOURNIER35d70ef2015-08-26 16:21:56 +02007079
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007080 This is used to delete an entry from an ACL. The ACL must be loaded from a
7081 file (even a dummy empty file). The file name of the ACL to be updated is
7082 passed between parentheses. It takes one argument: <key fmt>, which follows
7083 log-format rules, to collect content of the entry to delete.
7084 It is the equivalent of the "del acl" command from the stats socket, but can
7085 be triggered by an HTTP response.
Willy Tarreauf4c43c12013-06-11 17:01:13 +02007086
Maciej Zdebebdd4c52020-11-20 13:58:48 +00007087http-response del-header <name> [ -m <meth> ] [ { if | unless } <condition> ]
Willy Tarreau9a355ec2013-06-11 17:45:46 +02007088
Maciej Zdebebdd4c52020-11-20 13:58:48 +00007089 This removes all HTTP header fields whose name is specified in <name>. <meth>
7090 is the matching method, applied on the header name. Supported matching methods
7091 are "str" (exact match), "beg" (prefix match), "end" (suffix match), "sub"
7092 (substring match) and "reg" (regex match). If not specified, exact matching
7093 method is used.
Willy Tarreau42cf39e2013-06-11 18:51:32 +02007094
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007095http-response del-map(<file-name>) <key fmt> [ { if | unless } <condition> ]
Willy Tarreau51347ed2013-06-11 19:34:13 +02007096
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007097 This is used to delete an entry from a MAP. The MAP must be loaded from a
7098 file (even a dummy empty file). The file name of the MAP to be updated is
7099 passed between parentheses. It takes one argument: <key fmt>, which follows
7100 log-format rules, to collect content of the entry to delete.
7101 It takes one argument: "file name" It is the equivalent of the "del map"
7102 command from the stats socket, but can be triggered by an HTTP response.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007103
Christopher Faulet5cb513a2020-05-13 17:56:56 +02007104http-response deny [deny_status <status>] [ { if | unless } <condition> ]
7105http-response deny [ { status | deny_status } <code>] [content-type <type>]
7106 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
7107 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
7108 [ hdr <name> <fmt> ]*
7109 [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007110
Christopher Faulet5cb513a2020-05-13 17:56:56 +02007111 This stops the evaluation of the rules and immediately rejects the response.
7112 By default an HTTP 502 error is returned. But the response may be customized
7113 using same syntax than "http-response return" rules. Thus, see
Ilya Shipitsin11057a32020-06-21 21:18:27 +05007114 "http-response return" for details. For compatibility purpose, when no
Christopher Faulet5cb513a2020-05-13 17:56:56 +02007115 argument is defined, or only "deny_status", the argument "default-errorfiles"
7116 is implied. It means "http-response deny [deny_status <status>]" is an alias
7117 of "http-response deny [status <status>] default-errorfiles".
Christopher Faulet040c8cd2020-01-13 16:43:45 +01007118 No further "http-response" rules are evaluated.
Christopher Faulet5cb513a2020-05-13 17:56:56 +02007119 See also "http-response return".
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007120
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007121http-response redirect <rule> [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007122
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007123 This performs an HTTP redirection based on a redirect rule.
7124 This supports a format string similarly to "http-request redirect" rules,
7125 with the exception that only the "location" type of redirect is possible on
7126 the response. See the "redirect" keyword for the rule's syntax. When a
7127 redirect rule is applied during a response, connections to the server are
7128 closed so that no data can be forwarded from the server to the client.
Thierry FOURNIERe80fada2015-05-26 18:06:31 +02007129
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007130http-response replace-header <name> <regex-match> <replace-fmt>
7131 [ { if | unless } <condition> ]
Thierry FOURNIERe80fada2015-05-26 18:06:31 +02007132
Tim Duesterhus2252beb2019-10-29 00:05:13 +01007133 This works like "http-request replace-header" except that it works on the
7134 server's response instead of the client's request.
William Lallemand86d0df02017-11-24 21:36:45 +01007135
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007136 Example:
7137 http-response replace-header Set-Cookie (C=[^;]*);(.*) \1;ip=%bi;\2
Willy Tarreau51d861a2015-05-22 17:30:48 +02007138
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007139 # applied to:
7140 Set-Cookie: C=1; expires=Tue, 14-Jun-2016 01:40:45 GMT
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02007141
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007142 # outputs:
7143 Set-Cookie: C=1;ip=192.168.1.20; expires=Tue, 14-Jun-2016 01:40:45 GMT
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02007144
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007145 # assuming the backend IP is 192.168.1.20.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02007146
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007147http-response replace-value <name> <regex-match> <replace-fmt>
7148 [ { if | unless } <condition> ]
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02007149
Tim Duesterhus6bd909b2020-01-17 15:53:18 +01007150 This works like "http-request replace-value" except that it works on the
Tim Duesterhus2252beb2019-10-29 00:05:13 +01007151 server's response instead of the client's request.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +02007152
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007153 Example:
7154 http-response replace-value Cache-control ^public$ private
Christopher Faulet85d79c92016-11-09 16:54:56 +01007155
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007156 # applied to:
7157 Cache-Control: max-age=3600, public
Christopher Faulet85d79c92016-11-09 16:54:56 +01007158
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007159 # outputs:
7160 Cache-Control: max-age=3600, private
Christopher Faulet85d79c92016-11-09 16:54:56 +01007161
Christopher Faulet24231ab2020-01-24 17:44:23 +01007162http-response return [status <code>] [content-type <type>]
7163 [ { default-errorfiles | errorfile <file> | errorfiles <name> |
7164 file <file> | lf-file <file> | string <str> | lf-string <fmt> } ]
Christopher Faulet4a2c1422020-01-31 17:36:01 +01007165 [ hdr <name> <value> ]*
Christopher Faulet24231ab2020-01-24 17:44:23 +01007166 [ { if | unless } <condition> ]
7167
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05007168 This stops the evaluation of the rules and immediately returns a response. The
Christopher Faulet24231ab2020-01-24 17:44:23 +01007169 default status code used for the response is 200. It can be optionally
7170 specified as an arguments to "status". The response content-type may also be
Daniel Corbett67a82712020-07-06 23:01:19 -04007171 specified as an argument to "content-type". Finally the response itself may
Christopher Faulet24231ab2020-01-24 17:44:23 +01007172 be defined. If can be a full HTTP response specifying the errorfile to use,
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05007173 or the response payload specifying the file or the string to use. These rules
Christopher Faulet24231ab2020-01-24 17:44:23 +01007174 are followed to create the response :
7175
7176 * If neither the errorfile nor the payload to use is defined, a dummy
7177 response is returned. Only the "status" argument is considered. It can be
7178 any code in the range [200, 599]. The "content-type" argument, if any, is
7179 ignored.
7180
7181 * If "default-errorfiles" argument is set, the proxy's errorfiles are
7182 considered. If the "status" argument is defined, it must be one of the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007183 status code handled by HAProxy (200, 400, 403, 404, 405, 408, 410, 413,
Christopher Faulete095f312020-12-07 11:22:24 +01007184 425, 429, 500, 501, 502, 503, and 504). The "content-type" argument, if
7185 any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01007186
7187 * If a specific errorfile is defined, with an "errorfile" argument, the
7188 corresponding file, containing a full HTTP response, is returned. Only the
7189 "status" argument is considered. It must be one of the status code handled
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007190 by HAProxy (200, 400, 403, 404, 405, 408, 410, 413, 425, 429, 500, 501,
Christopher Faulete095f312020-12-07 11:22:24 +01007191 502, 503, and 504). The "content-type" argument, if any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01007192
7193 * If an http-errors section is defined, with an "errorfiles" argument, the
7194 corresponding file in the specified http-errors section, containing a full
7195 HTTP response, is returned. Only the "status" argument is considered. It
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007196 must be one of the status code handled by HAProxy (200, 400, 403, 404, 405,
Christopher Faulete095f312020-12-07 11:22:24 +01007197 408, 410, 413, 425, 429, 500, 501, 502, 503, and 504). The "content-type"
Anthonin Bonnefoy85048f82020-06-22 09:17:01 +02007198 argument, if any, is ignored.
Christopher Faulet24231ab2020-01-24 17:44:23 +01007199
7200 * If a "file" or a "lf-file" argument is specified, the file's content is
7201 used as the response payload. If the file is not empty, its content-type
7202 must be set as argument to "content-type". Otherwise, any "content-type"
7203 argument is ignored. With a "lf-file" argument, the file's content is
7204 evaluated as a log-format string. With a "file" argument, it is considered
7205 as a raw content.
7206
7207 * If a "string" or "lf-string" argument is specified, the defined string is
7208 used as the response payload. The content-type must always be set as
7209 argument to "content-type". With a "lf-string" argument, the string is
7210 evaluated as a log-format string. With a "string" argument, it is
7211 considered as a raw string.
7212
Christopher Faulet4a2c1422020-01-31 17:36:01 +01007213 When the response is not based an errorfile, it is possible to appends HTTP
7214 header fields to the response using "hdr" arguments. Otherwise, all "hdr"
7215 arguments are ignored. For each one, the header name is specified in <name>
7216 and its value is defined by <fmt> which follows the log-format rules.
7217
Christopher Faulet24231ab2020-01-24 17:44:23 +01007218 Note that the generated response must be smaller than a buffer. And to avoid
7219 any warning, when an errorfile or a raw file is loaded, the buffer space
Ilya Shipitsin11057a32020-06-21 21:18:27 +05007220 reserved to the headers rewriting should also be free.
Christopher Faulet24231ab2020-01-24 17:44:23 +01007221
7222 No further "http-response" rules are evaluated.
7223
7224 Example:
Daniel Corbett67a82712020-07-06 23:01:19 -04007225 http-response return errorfile /etc/haproxy/errorfiles/200.http \
Christopher Faulet24231ab2020-01-24 17:44:23 +01007226 if { status eq 404 }
7227
7228 http-response return content-type text/plain \
7229 string "This is the end !" \
7230 if { status eq 500 }
7231
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007232http-response sc-inc-gpc0(<sc-id>) [ { if | unless } <condition> ]
7233http-response sc-inc-gpc1(<sc-id>) [ { if | unless } <condition> ]
Ruoshan Huange4edc6b2016-07-14 15:07:45 +08007234
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007235 This action increments the GPC0 or GPC1 counter according with the sticky
7236 counter designated by <sc-id>. If an error occurs, this action silently fails
7237 and the actions evaluation continues.
Thierry FOURNIER236657b2015-08-19 08:25:14 +02007238
Cédric Dufour0d7712d2019-11-06 18:38:53 +01007239http-response sc-set-gpt0(<sc-id>) { <int> | <expr> }
7240 [ { if | unless } <condition> ]
Thierry FOURNIERe0627bd2015-08-04 08:20:33 +02007241
Cédric Dufour0d7712d2019-11-06 18:38:53 +01007242 This action sets the 32-bit unsigned GPT0 tag according to the sticky counter
7243 designated by <sc-id> and the value of <int>/<expr>. The expected result is a
7244 boolean. If an error occurs, this action silently fails and the actions
7245 evaluation continues.
Frédéric Lécaille6778b272018-01-29 15:22:53 +01007246
Christopher Faulet68fc3a12021-08-12 09:32:07 +02007247http-response send-spoe-group <engine-name> <group-name>
7248 [ { if | unless } <condition> ]
Willy Tarreau2d392c22015-08-24 01:43:45 +02007249
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007250 This action is used to trigger sending of a group of SPOE messages. To do so,
7251 the SPOE engine used to send messages must be defined, as well as the SPOE
7252 group to send. Of course, the SPOE engine must refer to an existing SPOE
7253 filter. If not engine name is provided on the SPOE filter line, the SPOE
7254 agent name must be used.
Christopher Faulet76c09ef2017-09-21 11:03:52 +02007255
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007256 Arguments:
7257 <engine-name> The SPOE engine name.
Christopher Faulet76c09ef2017-09-21 11:03:52 +02007258
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007259 <group-name> The SPOE group name as specified in the engine
7260 configuration.
Christopher Faulet76c09ef2017-09-21 11:03:52 +02007261
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007262http-response set-header <name> <fmt> [ { if | unless } <condition> ]
Willy Tarreaue365c0b2013-06-11 16:06:12 +02007263
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007264 This does the same as "add-header" except that the header name is first
7265 removed if it existed. This is useful when passing security information to
7266 the server, where the header must not be manipulated by external users.
Willy Tarreaue365c0b2013-06-11 16:06:12 +02007267
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007268http-response set-log-level <level> [ { if | unless } <condition> ]
7269
7270 This is used to change the log level of the current request when a certain
7271 condition is met. Valid levels are the 8 syslog levels (see the "log"
7272 keyword) plus the special level "silent" which disables logging for this
7273 request. This rule is not final so the last matching rule wins. This rule can
7274 be useful to disable health checks coming from another equipment.
7275
7276http-response set-map(<file-name>) <key fmt> <value fmt>
7277
7278 This is used to add a new entry into a MAP. The MAP must be loaded from a
7279 file (even a dummy empty file). The file name of the MAP to be updated is
7280 passed between parentheses. It takes 2 arguments: <key fmt>, which follows
7281 log-format rules, used to collect MAP key, and <value fmt>, which follows
7282 log-format rules, used to collect content for the new entry. It performs a
7283 lookup in the MAP before insertion, to avoid duplicated (or more) values.
7284 This lookup is done by a linear search and can be expensive with large lists!
7285 It is the equivalent of the "set map" command from the stats socket, but can
7286 be triggered by an HTTP response.
7287
7288http-response set-mark <mark> [ { if | unless } <condition> ]
7289
7290 This is used to set the Netfilter MARK on all packets sent to the client to
7291 the value passed in <mark> on platforms which support it. This value is an
7292 unsigned 32 bit value which can be matched by netfilter and by the routing
7293 table. It can be expressed both in decimal or hexadecimal format (prefixed
7294 by "0x"). This can be useful to force certain packets to take a different
7295 route (for example a cheaper network path for bulk downloads). This works on
7296 Linux kernels 2.6.32 and above and requires admin privileges.
7297
7298http-response set-nice <nice> [ { if | unless } <condition> ]
7299
7300 This sets the "nice" factor of the current request being processed.
7301 It only has effect against the other requests being processed at the same
7302 time. The default value is 0, unless altered by the "nice" setting on the
7303 "bind" line. The accepted range is -1024..1024. The higher the value, the
7304 nicest the request will be. Lower values will make the request more important
7305 than other ones. This can be useful to improve the speed of some requests, or
7306 lower the priority of non-important requests. Using this setting without
7307 prior experimentation can cause some major slowdown.
7308
7309http-response set-status <status> [reason <str>]
7310 [ { if | unless } <condition> ]
7311
7312 This replaces the response status code with <status> which must be an integer
7313 between 100 and 999. Optionally, a custom reason text can be provided defined
7314 by <str>, or the default reason for the specified code will be used as a
7315 fallback.
Ruoshan Huangeb5a3632015-12-08 21:00:23 +08007316
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007317 Example:
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007318 # return "431 Request Header Fields Too Large"
7319 http-response set-status 431
7320 # return "503 Slow Down", custom reason
7321 http-response set-status 503 reason "Slow Down".
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007322
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007323http-response set-tos <tos> [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007324
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007325 This is used to set the TOS or DSCP field value of packets sent to the client
7326 to the value passed in <tos> on platforms which support this.
7327 This value represents the whole 8 bits of the IP TOS field, and can be
7328 expressed both in decimal or hexadecimal format (prefixed by "0x"). Note that
7329 only the 6 higher bits are used in DSCP or TOS, and the two lower bits are
7330 always 0. This can be used to adjust some routing behavior on border routers
7331 based on some information from the request.
7332
7333 See RFC 2474, 2597, 3260 and 4594 for more information.
7334
7335http-response set-var(<var-name>) <expr> [ { if | unless } <condition> ]
7336
7337 This is used to set the contents of a variable. The variable is declared
7338 inline.
7339
7340 Arguments:
7341 <var-name> The name of the variable starts with an indication about its
7342 scope. The scopes allowed are:
7343 "proc" : the variable is shared with the whole process
7344 "sess" : the variable is shared with the whole session
7345 "txn" : the variable is shared with the transaction
7346 (request and response)
7347 "req" : the variable is shared only during request
7348 processing
7349 "res" : the variable is shared only during response
7350 processing
7351 This prefix is followed by a name. The separator is a '.'.
7352 The name may only contain characters 'a-z', 'A-Z', '0-9', '.'
7353 and '_'.
7354
7355 <expr> Is a standard HAProxy expression formed by a sample-fetch
7356 followed by some converters.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007357
7358 Example:
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007359 http-response set-var(sess.last_redir) res.hdr(location)
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007360
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007361http-response silent-drop [ { if | unless } <condition> ]
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007362
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007363 This stops the evaluation of the rules and makes the client-facing connection
7364 suddenly disappear using a system-dependent way that tries to prevent the
7365 client from being notified. The effect it then that the client still sees an
7366 established connection while there's none on HAProxy. The purpose is to
7367 achieve a comparable effect to "tarpit" except that it doesn't use any local
7368 resource at all on the machine running HAProxy. It can resist much higher
7369 loads than "tarpit", and slow down stronger attackers. It is important to
7370 understand the impact of using this mechanism. All stateful equipment placed
7371 between the client and HAProxy (firewalls, proxies, load balancers) will also
7372 keep the established connection for a long time and may suffer from this
7373 action.
7374 On modern Linux systems running with enough privileges, the TCP_REPAIR socket
7375 option is used to block the emission of a TCP reset. On other systems, the
7376 socket's TTL is reduced to 1 so that the TCP reset doesn't pass the first
7377 router, though it's still delivered to local networks. Do not use it unless
7378 you fully understand how it works.
Baptiste Assmannfabcbe02014-04-24 22:16:59 +02007379
Christopher Faulet46f95542019-12-20 10:07:22 +01007380http-response strict-mode { on | off }
7381
7382 This enables or disables the strict rewriting mode for following rules. It
7383 does not affect rules declared before it and it is only applicable on rules
7384 performing a rewrite on the responses. When the strict mode is enabled, any
7385 rewrite failure triggers an internal error. Otherwise, such errors are
7386 silently ignored. The purpose of the strict rewriting mode is to make some
Ilya Shipitsin8525fd92020-02-29 12:34:59 +05007387 rewrites optional while others must be performed to continue the response
Christopher Faulet46f95542019-12-20 10:07:22 +01007388 processing.
7389
Christopher Faulet1aea50e2020-01-17 16:03:53 +01007390 By default, the strict rewriting mode is enabled. Its value is also reset
Christopher Faulet46f95542019-12-20 10:07:22 +01007391 when a ruleset evaluation ends. So, for instance, if you change the mode on
Daniel Corbett67a82712020-07-06 23:01:19 -04007392 the backend, the default mode is restored when HAProxy starts the frontend
Christopher Faulet46f95542019-12-20 10:07:22 +01007393 rules evaluation.
7394
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007395http-response track-sc0 <key> [table <table>] [ { if | unless } <condition> ]
7396http-response track-sc1 <key> [table <table>] [ { if | unless } <condition> ]
7397http-response track-sc2 <key> [table <table>] [ { if | unless } <condition> ]
Willy Tarreaue365c0b2013-06-11 16:06:12 +02007398
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007399 This enables tracking of sticky counters from current response. Please refer
7400 to "http-request track-sc" for a complete description. The only difference
7401 from "http-request track-sc" is the <key> sample expression can only make use
7402 of samples in response (e.g. res.*, status etc.) and samples below Layer 6
7403 (e.g. SSL-related samples, see section 7.3.4). If the sample is not
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007404 supported, HAProxy will fail and warn while parsing the config.
Cyril Bonté6c81d5f2018-10-17 00:14:51 +02007405
7406http-response unset-var(<var-name>) [ { if | unless } <condition> ]
7407
7408 This is used to unset a variable. See "http-response set-var" for details
7409 about <var-name>.
7410
7411 Example:
7412 http-response unset-var(sess.last_redir)
7413
Christopher Faulet021a8e42021-03-29 10:46:38 +02007414http-response wait-for-body time <time> [ at-least <bytes> ]
7415 [ { if | unless } <condition> ]
7416
7417 This will delay the processing of the response waiting for the payload for at
7418 most <time> milliseconds. if "at-least" argument is specified, HAProxy stops
7419 to wait the payload when the first <bytes> bytes are received. 0 means no
7420 limit, it is the default value. Regardless the "at-least" argument value,
7421 HAProxy stops to wait if the whole payload is received or if the response
7422 buffer is full.
7423
7424 Arguments :
7425
7426 <time> is mandatory. It is the maximum time to wait for the body. It
7427 follows the HAProxy time format and is expressed in milliseconds.
7428
7429 <bytes> is optional. It is the minimum payload size to receive to stop to
Ilya Shipitsinb2be9a12021-04-24 13:25:42 +05007430 wait. It follows the HAProxy size format and is expressed in
Christopher Faulet021a8e42021-03-29 10:46:38 +02007431 bytes.
7432
7433 Example:
7434 http-response wait-for-body time 1s at-least 10k
Baptiste Assmann5ecb77f2013-10-06 23:24:13 +02007435
Willy Tarreau30631952015-08-06 15:05:24 +02007436http-reuse { never | safe | aggressive | always }
7437 Declare how idle HTTP connections may be shared between requests
7438
7439 May be used in sections: defaults | frontend | listen | backend
7440 yes | no | yes | yes
7441
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007442 By default, a connection established between HAProxy and the backend server
Olivier Houchard86006a52018-12-14 19:37:49 +01007443 which is considered safe for reuse is moved back to the server's idle
7444 connections pool so that any other request can make use of it. This is the
7445 "safe" strategy below.
Willy Tarreau30631952015-08-06 15:05:24 +02007446
7447 The argument indicates the desired connection reuse strategy :
7448
Olivier Houchard86006a52018-12-14 19:37:49 +01007449 - "never" : idle connections are never shared between sessions. This mode
7450 may be enforced to cancel a different strategy inherited from
7451 a defaults section or for troubleshooting. For example, if an
7452 old bogus application considers that multiple requests over
7453 the same connection come from the same client and it is not
7454 possible to fix the application, it may be desirable to
7455 disable connection sharing in a single backend. An example of
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007456 such an application could be an old HAProxy using cookie
Olivier Houchard86006a52018-12-14 19:37:49 +01007457 insertion in tunnel mode and not checking any request past the
7458 first one.
Willy Tarreau30631952015-08-06 15:05:24 +02007459
Olivier Houchard86006a52018-12-14 19:37:49 +01007460 - "safe" : this is the default and the recommended strategy. The first
7461 request of a session is always sent over its own connection,
7462 and only subsequent requests may be dispatched over other
7463 existing connections. This ensures that in case the server
7464 closes the connection when the request is being sent, the
7465 browser can decide to silently retry it. Since it is exactly
7466 equivalent to regular keep-alive, there should be no side
Amaury Denoyelle27179652020-10-14 18:17:12 +02007467 effects. There is also a special handling for the connections
7468 using protocols subject to Head-of-line blocking (backend with
7469 h2 or fcgi). In this case, when at least one stream is
7470 processed, the used connection is reserved to handle streams
7471 of the same session. When no more streams are processed, the
7472 connection is released and can be reused.
Willy Tarreau30631952015-08-06 15:05:24 +02007473
7474 - "aggressive" : this mode may be useful in webservices environments where
7475 all servers are not necessarily known and where it would be
7476 appreciable to deliver most first requests over existing
7477 connections. In this case, first requests are only delivered
7478 over existing connections that have been reused at least once,
7479 proving that the server correctly supports connection reuse.
7480 It should only be used when it's sure that the client can
7481 retry a failed request once in a while and where the benefit
Michael Prokop4438c602019-05-24 10:25:45 +02007482 of aggressive connection reuse significantly outweighs the
Willy Tarreau30631952015-08-06 15:05:24 +02007483 downsides of rare connection failures.
7484
7485 - "always" : this mode is only recommended when the path to the server is
7486 known for never breaking existing connections quickly after
7487 releasing them. It allows the first request of a session to be
7488 sent to an existing connection. This can provide a significant
7489 performance increase over the "safe" strategy when the backend
7490 is a cache farm, since such components tend to show a
Davor Ocelice9ed2812017-12-25 17:49:28 +01007491 consistent behavior and will benefit from the connection
Willy Tarreau30631952015-08-06 15:05:24 +02007492 sharing. It is recommended that the "http-keep-alive" timeout
7493 remains low in this mode so that no dead connections remain
7494 usable. In most cases, this will lead to the same performance
7495 gains as "aggressive" but with more risks. It should only be
7496 used when it improves the situation over "aggressive".
7497
7498 When http connection sharing is enabled, a great care is taken to respect the
Amaury Denoyelled773a4e2021-01-29 15:18:49 +01007499 connection properties and compatibility. Indeed, some properties are specific
7500 and it is not possibly to reuse it blindly. Those are the SSL SNI, source
7501 and destination address and proxy protocol block. A connection is reused only
7502 if it shares the same set of properties with the request.
Willy Tarreau30631952015-08-06 15:05:24 +02007503
Amaury Denoyelled773a4e2021-01-29 15:18:49 +01007504 Also note that connections with certain bogus authentication schemes (relying
7505 on the connection) like NTLM are marked private and never shared.
Willy Tarreau30631952015-08-06 15:05:24 +02007506
Lukas Tribuse8adfeb2019-11-06 11:50:25 +01007507 A connection pool is involved and configurable with "pool-max-conn".
Willy Tarreau30631952015-08-06 15:05:24 +02007508
7509 Note: connection reuse improves the accuracy of the "server maxconn" setting,
7510 because almost no new connection will be established while idle connections
7511 remain available. This is particularly true with the "always" strategy.
7512
7513 See also : "option http-keep-alive", "server maxconn"
7514
7515
Mark Lamourinec2247f02012-01-04 13:02:01 -05007516http-send-name-header [<header>]
7517 Add the server name to a request. Use the header string given by <header>
Mark Lamourinec2247f02012-01-04 13:02:01 -05007518 May be used in sections: defaults | frontend | listen | backend
7519 yes | no | yes | yes
Mark Lamourinec2247f02012-01-04 13:02:01 -05007520 Arguments :
Mark Lamourinec2247f02012-01-04 13:02:01 -05007521 <header> The header string to use to send the server name
7522
Willy Tarreau81bef7e2019-10-07 14:58:02 +02007523 The "http-send-name-header" statement causes the header field named <header>
7524 to be set to the name of the target server at the moment the request is about
7525 to be sent on the wire. Any existing occurrences of this header are removed.
7526 Upon retries and redispatches, the header field is updated to always reflect
7527 the server being attempted to connect to. Given that this header is modified
7528 very late in the connection setup, it may have unexpected effects on already
7529 modified headers. For example using it with transport-level header such as
7530 connection, content-length, transfer-encoding and so on will likely result in
7531 invalid requests being sent to the server. Additionally it has been reported
7532 that this directive is currently being used as a way to overwrite the Host
7533 header field in outgoing requests; while this trick has been known to work
7534 as a side effect of the feature for some time, it is not officially supported
7535 and might possibly not work anymore in a future version depending on the
7536 technical difficulties this feature induces. A long-term solution instead
7537 consists in fixing the application which required this trick so that it binds
7538 to the correct host name.
Mark Lamourinec2247f02012-01-04 13:02:01 -05007539
7540 See also : "server"
7541
Krzysztof Piotr Oledzkif58a9622008-02-23 01:19:10 +01007542id <value>
Willy Tarreau53fb4ae2009-10-04 23:04:08 +02007543 Set a persistent ID to a proxy.
7544 May be used in sections : defaults | frontend | listen | backend
7545 no | yes | yes | yes
7546 Arguments : none
7547
7548 Set a persistent ID for the proxy. This ID must be unique and positive.
7549 An unused ID will automatically be assigned if unset. The first assigned
7550 value will be 1. This ID is currently only returned in statistics.
Krzysztof Piotr Oledzkif58a9622008-02-23 01:19:10 +01007551
7552
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007553ignore-persist { if | unless } <condition>
7554 Declare a condition to ignore persistence
7555 May be used in sections: defaults | frontend | listen | backend
Cyril Bonté4288c5a2018-03-12 22:02:59 +01007556 no | no | yes | yes
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007557
7558 By default, when cookie persistence is enabled, every requests containing
7559 the cookie are unconditionally persistent (assuming the target server is up
7560 and running).
7561
7562 The "ignore-persist" statement allows one to declare various ACL-based
7563 conditions which, when met, will cause a request to ignore persistence.
7564 This is sometimes useful to load balance requests for static files, which
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03007565 often don't require persistence. This can also be used to fully disable
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007566 persistence for a specific User-Agent (for example, some web crawler bots).
7567
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007568 The persistence is ignored when an "if" condition is met, or unless an
7569 "unless" condition is met.
7570
Jarno Huuskonene5ae7022017-04-03 14:36:21 +03007571 Example:
7572 acl url_static path_beg /static /images /img /css
7573 acl url_static path_end .gif .png .jpg .css .js
7574 ignore-persist if url_static
7575
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007576 See also : "force-persist", "cookie", and section 7 about ACL usage.
7577
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007578load-server-state-from-file { global | local | none }
7579 Allow seamless reload of HAProxy
7580 May be used in sections: defaults | frontend | listen | backend
7581 yes | no | yes | yes
7582
7583 This directive points HAProxy to a file where server state from previous
7584 running process has been saved. That way, when starting up, before handling
7585 traffic, the new process can apply old states to servers exactly has if no
Davor Ocelice9ed2812017-12-25 17:49:28 +01007586 reload occurred. The purpose of the "load-server-state-from-file" directive is
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007587 to tell HAProxy which file to use. For now, only 2 arguments to either prevent
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007588 loading state or load states from a file containing all backends and servers.
7589 The state file can be generated by running the command "show servers state"
7590 over the stats socket and redirect output.
7591
Davor Ocelice9ed2812017-12-25 17:49:28 +01007592 The format of the file is versioned and is very specific. To understand it,
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007593 please read the documentation of the "show servers state" command (chapter
Willy Tarreau1af20c72017-06-23 16:01:14 +02007594 9.3 of Management Guide).
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007595
7596 Arguments:
7597 global load the content of the file pointed by the global directive
7598 named "server-state-file".
7599
7600 local load the content of the file pointed by the directive
7601 "server-state-file-name" if set. If not set, then the backend
7602 name is used as a file name.
7603
7604 none don't load any stat for this backend
7605
7606 Notes:
Willy Tarreaue5a60682016-11-09 14:54:53 +01007607 - server's IP address is preserved across reloads by default, but the
7608 order can be changed thanks to the server's "init-addr" setting. This
7609 means that an IP address change performed on the CLI at run time will
Davor Ocelice9ed2812017-12-25 17:49:28 +01007610 be preserved, and that any change to the local resolver (e.g. /etc/hosts)
Willy Tarreaue5a60682016-11-09 14:54:53 +01007611 will possibly not have any effect if the state file is in use.
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007612
7613 - server's weight is applied from previous running process unless it has
7614 has changed between previous and new configuration files.
7615
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007616 Example: Minimal configuration
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007617
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007618 global
7619 stats socket /tmp/socket
7620 server-state-file /tmp/server_state
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007621
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007622 defaults
7623 load-server-state-from-file global
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007624
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007625 backend bk
7626 server s1 127.0.0.1:22 check weight 11
7627 server s2 127.0.0.1:22 check weight 12
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007628
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007629
7630 Then one can run :
7631
7632 socat /tmp/socket - <<< "show servers state" > /tmp/server_state
7633
7634 Content of the file /tmp/server_state would be like this:
7635
7636 1
7637 # <field names skipped for the doc example>
7638 1 bk 1 s1 127.0.0.1 2 0 11 11 4 6 3 4 6 0 0
7639 1 bk 2 s2 127.0.0.1 2 0 12 12 4 6 3 4 6 0 0
7640
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007641 Example: Minimal configuration
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007642
7643 global
7644 stats socket /tmp/socket
7645 server-state-base /etc/haproxy/states
7646
7647 defaults
7648 load-server-state-from-file local
7649
7650 backend bk
7651 server s1 127.0.0.1:22 check weight 11
7652 server s2 127.0.0.1:22 check weight 12
7653
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02007654
Baptiste Assmann01c6cc32015-08-23 11:45:29 +02007655 Then one can run :
7656
7657 socat /tmp/socket - <<< "show servers state bk" > /etc/haproxy/states/bk
7658
7659 Content of the file /etc/haproxy/states/bk would be like this:
7660
7661 1
7662 # <field names skipped for the doc example>
7663 1 bk 1 s1 127.0.0.1 2 0 11 11 4 6 3 4 6 0 0
7664 1 bk 2 s2 127.0.0.1 2 0 12 12 4 6 3 4 6 0 0
7665
7666 See also: "server-state-file", "server-state-file-name", and
7667 "show servers state"
7668
Cyril Bonté0d4bf012010-04-25 23:21:46 +02007669
Willy Tarreau2769aa02007-12-27 18:26:09 +01007670log global
Jan Wagner3e678602020-12-17 22:22:32 +01007671log <address> [len <length>] [format <format>] [sample <ranges>:<sample_size>]
Frédéric Lécailled690dfa2019-04-25 10:52:17 +02007672 <facility> [<level> [<minlevel>]]
William Lallemand0f99e342011-10-12 17:50:54 +02007673no log
Willy Tarreau2769aa02007-12-27 18:26:09 +01007674 Enable per-instance logging of events and traffic.
7675 May be used in sections : defaults | frontend | listen | backend
7676 yes | yes | yes | yes
William Lallemand0f99e342011-10-12 17:50:54 +02007677
7678 Prefix :
7679 no should be used when the logger list must be flushed. For example,
7680 if you don't want to inherit from the default logger list. This
7681 prefix does not allow arguments.
7682
Willy Tarreau2769aa02007-12-27 18:26:09 +01007683 Arguments :
7684 global should be used when the instance's logging parameters are the
7685 same as the global ones. This is the most common usage. "global"
7686 replaces <address>, <facility> and <level> with those of the log
7687 entries found in the "global" section. Only one "log global"
7688 statement may be used per instance, and this form takes no other
7689 parameter.
7690
7691 <address> indicates where to send the logs. It takes the same format as
7692 for the "global" section's logs, and can be one of :
7693
7694 - An IPv4 address optionally followed by a colon (':') and a UDP
7695 port. If no port is specified, 514 is used by default (the
7696 standard syslog port).
7697
David du Colombier24bb5f52011-03-17 10:40:23 +01007698 - An IPv6 address followed by a colon (':') and optionally a UDP
7699 port. If no port is specified, 514 is used by default (the
7700 standard syslog port).
7701
Willy Tarreau2769aa02007-12-27 18:26:09 +01007702 - A filesystem path to a UNIX domain socket, keeping in mind
7703 considerations for chroot (be sure the path is accessible
7704 inside the chroot) and uid/gid (be sure the path is
Davor Ocelice9ed2812017-12-25 17:49:28 +01007705 appropriately writable).
Willy Tarreau2769aa02007-12-27 18:26:09 +01007706
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01007707 - A file descriptor number in the form "fd@<number>", which may
7708 point to a pipe, terminal, or socket. In this case unbuffered
7709 logs are used and one writev() call per log is performed. This
7710 is a bit expensive but acceptable for most workloads. Messages
7711 sent this way will not be truncated but may be dropped, in
7712 which case the DroppedLogs counter will be incremented. The
7713 writev() call is atomic even on pipes for messages up to
7714 PIPE_BUF size, which POSIX recommends to be at least 512 and
7715 which is 4096 bytes on most modern operating systems. Any
7716 larger message may be interleaved with messages from other
7717 processes. Exceptionally for debugging purposes the file
7718 descriptor may also be directed to a file, but doing so will
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007719 significantly slow HAProxy down as non-blocking calls will be
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01007720 ignored. Also there will be no way to purge nor rotate this
7721 file without restarting the process. Note that the configured
7722 syslog format is preserved, so the output is suitable for use
Willy Tarreauc1b06452018-11-12 11:57:56 +01007723 with a TCP syslog server. See also the "short" and "raw"
7724 formats below.
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01007725
7726 - "stdout" / "stderr", which are respectively aliases for "fd@1"
7727 and "fd@2", see above.
7728
Willy Tarreauc046d162019-08-30 15:24:59 +02007729 - A ring buffer in the form "ring@<name>", which will correspond
7730 to an in-memory ring buffer accessible over the CLI using the
7731 "show events" command, which will also list existing rings and
7732 their sizes. Such buffers are lost on reload or restart but
7733 when used as a complement this can help troubleshooting by
7734 having the logs instantly available.
7735
Emeric Brun94aab062021-04-02 10:41:36 +02007736 - An explicit stream address prefix such as "tcp@","tcp6@",
7737 "tcp4@" or "uxst@" will allocate an implicit ring buffer with
7738 a stream forward server targeting the given address.
7739
Willy Tarreau5a32ecc2018-11-12 07:34:59 +01007740 You may want to reference some environment variables in the
7741 address parameter, see section 2.3 about environment variables.
Willy Tarreaudad36a32013-03-11 01:20:04 +01007742
Willy Tarreau18324f52014-06-27 18:10:07 +02007743 <length> is an optional maximum line length. Log lines larger than this
7744 value will be truncated before being sent. The reason is that
7745 syslog servers act differently on log line length. All servers
7746 support the default value of 1024, but some servers simply drop
7747 larger lines while others do log them. If a server supports long
7748 lines, it may make sense to set this value here in order to avoid
7749 truncating long lines. Similarly, if a server drops long lines,
7750 it is preferable to truncate them before sending them. Accepted
7751 values are 80 to 65535 inclusive. The default value of 1024 is
7752 generally fine for all standard usages. Some specific cases of
Davor Ocelice9ed2812017-12-25 17:49:28 +01007753 long captures or JSON-formatted logs may require larger values.
Willy Tarreau18324f52014-06-27 18:10:07 +02007754
Frédéric Lécailled690dfa2019-04-25 10:52:17 +02007755 <ranges> A list of comma-separated ranges to identify the logs to sample.
7756 This is used to balance the load of the logs to send to the log
7757 server. The limits of the ranges cannot be null. They are numbered
7758 from 1. The size or period (in number of logs) of the sample must
7759 be set with <sample_size> parameter.
7760
7761 <sample_size>
7762 The size of the sample in number of logs to consider when balancing
7763 their logging loads. It is used to balance the load of the logs to
7764 send to the syslog server. This size must be greater or equal to the
7765 maximum of the high limits of the ranges.
7766 (see also <ranges> parameter).
7767
Willy Tarreauadb345d2018-11-12 07:56:13 +01007768 <format> is the log format used when generating syslog messages. It may be
7769 one of the following :
7770
Emeric Brun0237c4e2020-11-27 16:24:34 +01007771 local Analog to rfc3164 syslog message format except that hostname
7772 field is stripped. This is the default.
7773 Note: option "log-send-hostname" switches the default to
7774 rfc3164.
7775
7776 rfc3164 The RFC3164 syslog message format.
Willy Tarreauadb345d2018-11-12 07:56:13 +01007777 (https://tools.ietf.org/html/rfc3164)
7778
7779 rfc5424 The RFC5424 syslog message format.
7780 (https://tools.ietf.org/html/rfc5424)
7781
Emeric Brun54648852020-07-06 15:54:06 +02007782 priority A message containing only a level plus syslog facility between
7783 angle brackets such as '<63>', followed by the text. The PID,
7784 date, time, process name and system name are omitted. This is
7785 designed to be used with a local log server.
7786
Willy Tarreaue8746a02018-11-12 08:45:00 +01007787 short A message containing only a level between angle brackets such as
7788 '<3>', followed by the text. The PID, date, time, process name
7789 and system name are omitted. This is designed to be used with a
7790 local log server. This format is compatible with what the
7791 systemd logger consumes.
7792
Emeric Brun54648852020-07-06 15:54:06 +02007793 timed A message containing only a level between angle brackets such as
7794 '<3>', followed by ISO date and by the text. The PID, process
7795 name and system name are omitted. This is designed to be
7796 used with a local log server.
7797
7798 iso A message containing only the ISO date, followed by the text.
7799 The PID, process name and system name are omitted. This is
7800 designed to be used with a local log server.
7801
Willy Tarreauc1b06452018-11-12 11:57:56 +01007802 raw A message containing only the text. The level, PID, date, time,
7803 process name and system name are omitted. This is designed to
7804 be used in containers or during development, where the severity
7805 only depends on the file descriptor used (stdout/stderr).
7806
Willy Tarreau2769aa02007-12-27 18:26:09 +01007807 <facility> must be one of the 24 standard syslog facilities :
7808
Willy Tarreaue8746a02018-11-12 08:45:00 +01007809 kern user mail daemon auth syslog lpr news
7810 uucp cron auth2 ftp ntp audit alert cron2
7811 local0 local1 local2 local3 local4 local5 local6 local7
7812
Willy Tarreauc1b06452018-11-12 11:57:56 +01007813 Note that the facility is ignored for the "short" and "raw"
7814 formats, but still required as a positional field. It is
7815 recommended to use "daemon" in this case to make it clear that
7816 it's only supposed to be used locally.
Willy Tarreau2769aa02007-12-27 18:26:09 +01007817
7818 <level> is optional and can be specified to filter outgoing messages. By
7819 default, all messages are sent. If a level is specified, only
7820 messages with a severity at least as important as this level
Willy Tarreauf7edefa2009-05-10 17:20:05 +02007821 will be sent. An optional minimum level can be specified. If it
7822 is set, logs emitted with a more severe level than this one will
7823 be capped to this level. This is used to avoid sending "emerg"
7824 messages on all terminals on some default syslog configurations.
7825 Eight levels are known :
Willy Tarreau2769aa02007-12-27 18:26:09 +01007826
7827 emerg alert crit err warning notice info debug
7828
William Lallemand0f99e342011-10-12 17:50:54 +02007829 It is important to keep in mind that it is the frontend which decides what to
7830 log from a connection, and that in case of content switching, the log entries
7831 from the backend will be ignored. Connections are logged at level "info".
Willy Tarreaucc6c8912009-02-22 10:53:55 +01007832
7833 However, backend log declaration define how and where servers status changes
7834 will be logged. Level "notice" will be used to indicate a server going up,
7835 "warning" will be used for termination signals and definitive service
7836 termination, and "alert" will be used for when a server goes down.
7837
7838 Note : According to RFC3164, messages are truncated to 1024 bytes before
7839 being emitted.
Willy Tarreau2769aa02007-12-27 18:26:09 +01007840
7841 Example :
7842 log global
Willy Tarreauc1b06452018-11-12 11:57:56 +01007843 log stdout format short daemon # send log to systemd
7844 log stdout format raw daemon # send everything to stdout
7845 log stderr format raw daemon notice # send important events to stderr
Willy Tarreauf7edefa2009-05-10 17:20:05 +02007846 log 127.0.0.1:514 local0 notice # only send important events
Emeric Brun94aab062021-04-02 10:41:36 +02007847 log tcp@127.0.0.1:514 local0 notice notice # same but limit output
7848 # level and send in tcp
William Lallemandb2f07452015-05-12 14:27:13 +02007849 log "${LOCAL_SYSLOG}:514" local0 notice # send to local server
Willy Tarreaudad36a32013-03-11 01:20:04 +01007850
Willy Tarreau2769aa02007-12-27 18:26:09 +01007851
William Lallemand48940402012-01-30 16:47:22 +01007852log-format <string>
Willy Tarreaufb4e7ea2015-01-07 14:55:17 +01007853 Specifies the log format string to use for traffic logs
7854 May be used in sections: defaults | frontend | listen | backend
7855 yes | yes | yes | no
William Lallemand48940402012-01-30 16:47:22 +01007856
Willy Tarreaufb4e7ea2015-01-07 14:55:17 +01007857 This directive specifies the log format string that will be used for all logs
7858 resulting from traffic passing through the frontend using this line. If the
7859 directive is used in a defaults section, all subsequent frontends will use
7860 the same log format. Please see section 8.2.4 which covers the log format
7861 string in depth.
William Lallemand48940402012-01-30 16:47:22 +01007862
Guillaume de Lafond29f45602017-03-31 19:52:15 +02007863 "log-format" directive overrides previous "option tcplog", "log-format" and
7864 "option httplog" directives.
7865
Dragan Dosen7ad31542015-09-28 17:16:47 +02007866log-format-sd <string>
7867 Specifies the RFC5424 structured-data log format string
7868 May be used in sections: defaults | frontend | listen | backend
7869 yes | yes | yes | no
7870
7871 This directive specifies the RFC5424 structured-data log format string that
7872 will be used for all logs resulting from traffic passing through the frontend
7873 using this line. If the directive is used in a defaults section, all
7874 subsequent frontends will use the same log format. Please see section 8.2.4
7875 which covers the log format string in depth.
7876
7877 See https://tools.ietf.org/html/rfc5424#section-6.3 for more information
7878 about the RFC5424 structured-data part.
7879
7880 Note : This log format string will be used only for loggers that have set
7881 log format to "rfc5424".
7882
7883 Example :
7884 log-format-sd [exampleSDID@1234\ bytes=\"%B\"\ status=\"%ST\"]
7885
7886
Willy Tarreau094af4e2015-01-07 15:03:42 +01007887log-tag <string>
7888 Specifies the log tag to use for all outgoing logs
7889 May be used in sections: defaults | frontend | listen | backend
7890 yes | yes | yes | yes
7891
7892 Sets the tag field in the syslog header to this string. It defaults to the
7893 log-tag set in the global section, otherwise the program name as launched
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007894 from the command line, which usually is "HAProxy". Sometimes it can be useful
Willy Tarreau094af4e2015-01-07 15:03:42 +01007895 to differentiate between multiple processes running on the same host, or to
7896 differentiate customer instances running in the same process. In the backend,
7897 logs about servers up/down will use this tag. As a hint, it can be convenient
7898 to set a log-tag related to a hosted customer in a defaults section then put
7899 all the frontends and backends for that customer, then start another customer
7900 in a new defaults section. See also the global "log-tag" directive.
Willy Tarreau2769aa02007-12-27 18:26:09 +01007901
Willy Tarreauc35362a2014-04-25 13:58:37 +02007902max-keep-alive-queue <value>
7903 Set the maximum server queue size for maintaining keep-alive connections
7904 May be used in sections: defaults | frontend | listen | backend
7905 yes | no | yes | yes
7906
7907 HTTP keep-alive tries to reuse the same server connection whenever possible,
7908 but sometimes it can be counter-productive, for example if a server has a lot
7909 of connections while other ones are idle. This is especially true for static
7910 servers.
7911
7912 The purpose of this setting is to set a threshold on the number of queued
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007913 connections at which HAProxy stops trying to reuse the same server and prefers
Willy Tarreauc35362a2014-04-25 13:58:37 +02007914 to find another one. The default value, -1, means there is no limit. A value
7915 of zero means that keep-alive requests will never be queued. For very close
7916 servers which can be reached with a low latency and which are not sensible to
Davor Ocelice9ed2812017-12-25 17:49:28 +01007917 breaking keep-alive, a low value is recommended (e.g. local static server can
Willy Tarreauc35362a2014-04-25 13:58:37 +02007918 use a value of 10 or less). For remote servers suffering from a high latency,
7919 higher values might be needed to cover for the latency and/or the cost of
7920 picking a different server.
7921
7922 Note that this has no impact on responses which are maintained to the same
7923 server consecutively to a 401 response. They will still go to the same server
7924 even if they have to be queued.
7925
7926 See also : "option http-server-close", "option prefer-last-server", server
7927 "maxconn" and cookie persistence.
7928
Olivier Houcharda4d4fdf2018-12-14 19:27:06 +01007929max-session-srv-conns <nb>
7930 Set the maximum number of outgoing connections we can keep idling for a given
7931 client session. The default is 5 (it precisely equals MAX_SRV_LIST which is
7932 defined at build time).
Willy Tarreauc35362a2014-04-25 13:58:37 +02007933
Willy Tarreau2769aa02007-12-27 18:26:09 +01007934maxconn <conns>
7935 Fix the maximum number of concurrent connections on a frontend
7936 May be used in sections : defaults | frontend | listen | backend
7937 yes | yes | yes | no
7938 Arguments :
7939 <conns> is the maximum number of concurrent connections the frontend will
7940 accept to serve. Excess connections will be queued by the system
7941 in the socket's listen queue and will be served once a connection
7942 closes.
7943
7944 If the system supports it, it can be useful on big sites to raise this limit
Daniel Corbett9f0843f2021-05-08 10:50:37 -04007945 very high so that HAProxy manages connection queues, instead of leaving the
Willy Tarreau2769aa02007-12-27 18:26:09 +01007946 clients with unanswered connection attempts. This value should not exceed the
7947 global maxconn. Also, keep in mind that a connection contains two buffers
Baptiste Assmann79fb45d2016-03-06 23:34:31 +01007948 of tune.bufsize (16kB by default) each, as well as some other data resulting
7949 in about 33 kB of RAM being consumed per established connection. That means
7950 that a medium system equipped with 1GB of RAM can withstand around
7951 20000-25000 concurrent connections if properly tuned.
Willy Tarreau2769aa02007-12-27 18:26:09 +01007952
7953 Also, when <conns> is set to large values, it is possible that the servers
7954 are not sized to accept such loads, and for this reason it is generally wise
7955 to assign them some reasonable connection limits.
7956
Willy Tarreauc8d5b952019-02-27 17:25:52 +01007957 When this value is set to zero, which is the default, the global "maxconn"
7958 value is used.
Vincent Bernat6341be52012-06-27 17:18:30 +02007959
Willy Tarreau2769aa02007-12-27 18:26:09 +01007960 See also : "server", global section's "maxconn", "fullconn"
7961
7962
Willy Tarreau77e0dae2020-10-14 15:44:27 +02007963mode { tcp|http }
Willy Tarreau2769aa02007-12-27 18:26:09 +01007964 Set the running mode or protocol of the instance
7965 May be used in sections : defaults | frontend | listen | backend
7966 yes | yes | yes | yes
7967 Arguments :
7968 tcp The instance will work in pure TCP mode. A full-duplex connection
7969 will be established between clients and servers, and no layer 7
7970 examination will be performed. This is the default mode. It
7971 should be used for SSL, SSH, SMTP, ...
7972
7973 http The instance will work in HTTP mode. The client request will be
7974 analyzed in depth before connecting to any server. Any request
7975 which is not RFC-compliant will be rejected. Layer 7 filtering,
7976 processing and switching will be possible. This is the mode which
7977 brings HAProxy most of its value.
7978
Cyril Bonté108cf6e2012-04-21 23:30:29 +02007979 When doing content switching, it is mandatory that the frontend and the
7980 backend are in the same mode (generally HTTP), otherwise the configuration
7981 will be refused.
Willy Tarreau2769aa02007-12-27 18:26:09 +01007982
Cyril Bonté108cf6e2012-04-21 23:30:29 +02007983 Example :
Willy Tarreau2769aa02007-12-27 18:26:09 +01007984 defaults http_instances
7985 mode http
7986
Willy Tarreau0ba27502007-12-24 16:55:16 +01007987
Cyril Bontéf0c60612010-02-06 14:44:47 +01007988monitor fail { if | unless } <condition>
Willy Tarreau2769aa02007-12-27 18:26:09 +01007989 Add a condition to report a failure to a monitor HTTP request.
Willy Tarreau0ba27502007-12-24 16:55:16 +01007990 May be used in sections : defaults | frontend | listen | backend
7991 no | yes | yes | no
Willy Tarreau0ba27502007-12-24 16:55:16 +01007992 Arguments :
7993 if <cond> the monitor request will fail if the condition is satisfied,
7994 and will succeed otherwise. The condition should describe a
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01007995 combined test which must induce a failure if all conditions
Willy Tarreau0ba27502007-12-24 16:55:16 +01007996 are met, for instance a low number of servers both in a
7997 backend and its backup.
7998
7999 unless <cond> the monitor request will succeed only if the condition is
8000 satisfied, and will fail otherwise. Such a condition may be
8001 based on a test on the presence of a minimum number of active
8002 servers in a list of backends.
8003
8004 This statement adds a condition which can force the response to a monitor
8005 request to report a failure. By default, when an external component queries
8006 the URI dedicated to monitoring, a 200 response is returned. When one of the
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008007 conditions above is met, HAProxy will return 503 instead of 200. This is
Willy Tarreau0ba27502007-12-24 16:55:16 +01008008 very useful to report a site failure to an external component which may base
8009 routing advertisements between multiple sites on the availability reported by
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008010 HAProxy. In this case, one would rely on an ACL involving the "nbsrv"
Willy Tarreauae94d4d2011-05-11 16:28:49 +02008011 criterion. Note that "monitor fail" only works in HTTP mode. Both status
8012 messages may be tweaked using "errorfile" or "errorloc" if needed.
Willy Tarreau0ba27502007-12-24 16:55:16 +01008013
8014 Example:
8015 frontend www
Willy Tarreau2769aa02007-12-27 18:26:09 +01008016 mode http
Willy Tarreau0ba27502007-12-24 16:55:16 +01008017 acl site_dead nbsrv(dynamic) lt 2
8018 acl site_dead nbsrv(static) lt 2
8019 monitor-uri /site_alive
8020 monitor fail if site_dead
8021
Willy Tarreau9e9919d2020-10-14 15:55:23 +02008022 See also : "monitor-uri", "errorfile", "errorloc"
Willy Tarreau2769aa02007-12-27 18:26:09 +01008023
8024
Willy Tarreau2769aa02007-12-27 18:26:09 +01008025monitor-uri <uri>
8026 Intercept a URI used by external components' monitor requests
8027 May be used in sections : defaults | frontend | listen | backend
8028 yes | yes | yes | no
8029 Arguments :
8030 <uri> is the exact URI which we want to intercept to return HAProxy's
8031 health status instead of forwarding the request.
8032
8033 When an HTTP request referencing <uri> will be received on a frontend,
8034 HAProxy will not forward it nor log it, but instead will return either
8035 "HTTP/1.0 200 OK" or "HTTP/1.0 503 Service unavailable", depending on failure
8036 conditions defined with "monitor fail". This is normally enough for any
8037 front-end HTTP probe to detect that the service is UP and running without
8038 forwarding the request to a backend server. Note that the HTTP method, the
8039 version and all headers are ignored, but the request must at least be valid
8040 at the HTTP level. This keyword may only be used with an HTTP-mode frontend.
8041
Willy Tarreau721d8e02017-12-01 18:25:08 +01008042 Monitor requests are processed very early, just after the request is parsed
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02008043 and even before any "http-request". The only rulesets applied before are the
8044 tcp-request ones. They cannot be logged either, and it is the intended
8045 purpose. They are only used to report HAProxy's health to an upper component,
8046 nothing more. However, it is possible to add any number of conditions using
8047 "monitor fail" and ACLs so that the result can be adjusted to whatever check
8048 can be imagined (most often the number of available servers in a backend).
Willy Tarreau2769aa02007-12-27 18:26:09 +01008049
Christopher Faulet6072beb2020-02-18 15:34:58 +01008050 Note: if <uri> starts by a slash ('/'), the matching is performed against the
8051 request's path instead of the request's uri. It is a workaround to let
8052 the HTTP/2 requests match the monitor-uri. Indeed, in HTTP/2, clients
8053 are encouraged to send absolute URIs only.
8054
Willy Tarreau2769aa02007-12-27 18:26:09 +01008055 Example :
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008056 # Use /haproxy_test to report HAProxy's status
Willy Tarreau2769aa02007-12-27 18:26:09 +01008057 frontend www
8058 mode http
8059 monitor-uri /haproxy_test
8060
Willy Tarreau9e9919d2020-10-14 15:55:23 +02008061 See also : "monitor fail"
Willy Tarreau2769aa02007-12-27 18:26:09 +01008062
Willy Tarreau0ba27502007-12-24 16:55:16 +01008063
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008064option abortonclose
8065no option abortonclose
8066 Enable or disable early dropping of aborted requests pending in queues.
8067 May be used in sections : defaults | frontend | listen | backend
8068 yes | no | yes | yes
8069 Arguments : none
8070
8071 In presence of very high loads, the servers will take some time to respond.
8072 The per-instance connection queue will inflate, and the response time will
8073 increase respective to the size of the queue times the average per-session
8074 response time. When clients will wait for more than a few seconds, they will
Willy Tarreau198a7442008-01-17 12:05:32 +01008075 often hit the "STOP" button on their browser, leaving a useless request in
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008076 the queue, and slowing down other users, and the servers as well, because the
8077 request will eventually be served, then aborted at the first error
8078 encountered while delivering the response.
8079
8080 As there is no way to distinguish between a full STOP and a simple output
8081 close on the client side, HTTP agents should be conservative and consider
8082 that the client might only have closed its output channel while waiting for
8083 the response. However, this introduces risks of congestion when lots of users
8084 do the same, and is completely useless nowadays because probably no client at
8085 all will close the session while waiting for the response. Some HTTP agents
Davor Ocelice9ed2812017-12-25 17:49:28 +01008086 support this behavior (Squid, Apache, HAProxy), and others do not (TUX, most
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008087 hardware-based load balancers). So the probability for a closed input channel
Willy Tarreau198a7442008-01-17 12:05:32 +01008088 to represent a user hitting the "STOP" button is close to 100%, and the risk
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008089 of being the single component to break rare but valid traffic is extremely
8090 low, which adds to the temptation to be able to abort a session early while
8091 still not served and not pollute the servers.
8092
Davor Ocelice9ed2812017-12-25 17:49:28 +01008093 In HAProxy, the user can choose the desired behavior using the option
8094 "abortonclose". By default (without the option) the behavior is HTTP
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008095 compliant and aborted requests will be served. But when the option is
8096 specified, a session with an incoming channel closed will be aborted while
8097 it is still possible, either pending in the queue for a connection slot, or
8098 during the connection establishment if the server has not yet acknowledged
8099 the connection request. This considerably reduces the queue size and the load
8100 on saturated servers when users are tempted to click on STOP, which in turn
Willy Tarreaud72758d2010-01-12 10:42:19 +01008101 reduces the response time for other users.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008102
8103 If this option has been enabled in a "defaults" section, it can be disabled
8104 in a specific instance by prepending the "no" keyword before it.
8105
8106 See also : "timeout queue" and server's "maxconn" and "maxqueue" parameters
8107
8108
Willy Tarreau4076a152009-04-02 15:18:36 +02008109option accept-invalid-http-request
8110no option accept-invalid-http-request
8111 Enable or disable relaxing of HTTP request parsing
8112 May be used in sections : defaults | frontend | listen | backend
8113 yes | yes | yes | no
8114 Arguments : none
8115
Willy Tarreau91852eb2015-05-01 13:26:00 +02008116 By default, HAProxy complies with RFC7230 in terms of message parsing. This
Willy Tarreau4076a152009-04-02 15:18:36 +02008117 means that invalid characters in header names are not permitted and cause an
Davor Ocelice9ed2812017-12-25 17:49:28 +01008118 error to be returned to the client. This is the desired behavior as such
Willy Tarreau4076a152009-04-02 15:18:36 +02008119 forbidden characters are essentially used to build attacks exploiting server
8120 weaknesses, and bypass security filtering. Sometimes, a buggy browser or
8121 server will emit invalid header names for whatever reason (configuration,
8122 implementation) and the issue will not be immediately fixed. In such a case,
8123 it is possible to relax HAProxy's header name parser to accept any character
Willy Tarreau422246e2012-01-07 23:54:13 +01008124 even if that does not make sense, by specifying this option. Similarly, the
8125 list of characters allowed to appear in a URI is well defined by RFC3986, and
8126 chars 0-31, 32 (space), 34 ('"'), 60 ('<'), 62 ('>'), 92 ('\'), 94 ('^'), 96
8127 ('`'), 123 ('{'), 124 ('|'), 125 ('}'), 127 (delete) and anything above are
Davor Ocelice9ed2812017-12-25 17:49:28 +01008128 not allowed at all. HAProxy always blocks a number of them (0..32, 127). The
Willy Tarreau91852eb2015-05-01 13:26:00 +02008129 remaining ones are blocked by default unless this option is enabled. This
Willy Tarreau13317662015-05-01 13:47:08 +02008130 option also relaxes the test on the HTTP version, it allows HTTP/0.9 requests
8131 to pass through (no version specified) and multiple digits for both the major
8132 and the minor version.
Willy Tarreau4076a152009-04-02 15:18:36 +02008133
8134 This option should never be enabled by default as it hides application bugs
8135 and open security breaches. It should only be deployed after a problem has
8136 been confirmed.
8137
8138 When this option is enabled, erroneous header names will still be accepted in
8139 requests, but the complete request will be captured in order to permit later
Willy Tarreau422246e2012-01-07 23:54:13 +01008140 analysis using the "show errors" request on the UNIX stats socket. Similarly,
8141 requests containing invalid chars in the URI part will be logged. Doing this
Willy Tarreau4076a152009-04-02 15:18:36 +02008142 also helps confirming that the issue has been solved.
8143
8144 If this option has been enabled in a "defaults" section, it can be disabled
8145 in a specific instance by prepending the "no" keyword before it.
8146
8147 See also : "option accept-invalid-http-response" and "show errors" on the
8148 stats socket.
8149
8150
8151option accept-invalid-http-response
8152no option accept-invalid-http-response
8153 Enable or disable relaxing of HTTP response parsing
8154 May be used in sections : defaults | frontend | listen | backend
8155 yes | no | yes | yes
8156 Arguments : none
8157
Willy Tarreau91852eb2015-05-01 13:26:00 +02008158 By default, HAProxy complies with RFC7230 in terms of message parsing. This
Willy Tarreau4076a152009-04-02 15:18:36 +02008159 means that invalid characters in header names are not permitted and cause an
Davor Ocelice9ed2812017-12-25 17:49:28 +01008160 error to be returned to the client. This is the desired behavior as such
Willy Tarreau4076a152009-04-02 15:18:36 +02008161 forbidden characters are essentially used to build attacks exploiting server
8162 weaknesses, and bypass security filtering. Sometimes, a buggy browser or
8163 server will emit invalid header names for whatever reason (configuration,
8164 implementation) and the issue will not be immediately fixed. In such a case,
8165 it is possible to relax HAProxy's header name parser to accept any character
Willy Tarreau91852eb2015-05-01 13:26:00 +02008166 even if that does not make sense, by specifying this option. This option also
8167 relaxes the test on the HTTP version format, it allows multiple digits for
8168 both the major and the minor version.
Willy Tarreau4076a152009-04-02 15:18:36 +02008169
8170 This option should never be enabled by default as it hides application bugs
8171 and open security breaches. It should only be deployed after a problem has
8172 been confirmed.
8173
8174 When this option is enabled, erroneous header names will still be accepted in
8175 responses, but the complete response will be captured in order to permit
8176 later analysis using the "show errors" request on the UNIX stats socket.
8177 Doing this also helps confirming that the issue has been solved.
8178
8179 If this option has been enabled in a "defaults" section, it can be disabled
8180 in a specific instance by prepending the "no" keyword before it.
8181
8182 See also : "option accept-invalid-http-request" and "show errors" on the
8183 stats socket.
8184
8185
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008186option allbackups
8187no option allbackups
8188 Use either all backup servers at a time or only the first one
8189 May be used in sections : defaults | frontend | listen | backend
8190 yes | no | yes | yes
8191 Arguments : none
8192
8193 By default, the first operational backup server gets all traffic when normal
8194 servers are all down. Sometimes, it may be preferred to use multiple backups
8195 at once, because one will not be enough. When "option allbackups" is enabled,
8196 the load balancing will be performed among all backup servers when all normal
8197 ones are unavailable. The same load balancing algorithm will be used and the
8198 servers' weights will be respected. Thus, there will not be any priority
8199 order between the backup servers anymore.
8200
8201 This option is mostly used with static server farms dedicated to return a
8202 "sorry" page when an application is completely offline.
8203
8204 If this option has been enabled in a "defaults" section, it can be disabled
8205 in a specific instance by prepending the "no" keyword before it.
8206
8207
8208option checkcache
8209no option checkcache
Godbach7056a352013-12-11 20:01:07 +08008210 Analyze all server responses and block responses with cacheable cookies
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008211 May be used in sections : defaults | frontend | listen | backend
8212 yes | no | yes | yes
8213 Arguments : none
8214
8215 Some high-level frameworks set application cookies everywhere and do not
8216 always let enough control to the developer to manage how the responses should
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01008217 be cached. When a session cookie is returned on a cacheable object, there is a
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008218 high risk of session crossing or stealing between users traversing the same
8219 caches. In some situations, it is better to block the response than to let
Willy Tarreau3c92c5f2011-08-28 09:45:47 +02008220 some sensitive session information go in the wild.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008221
8222 The option "checkcache" enables deep inspection of all server responses for
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01008223 strict compliance with HTTP specification in terms of cacheability. It
Willy Tarreau198a7442008-01-17 12:05:32 +01008224 carefully checks "Cache-control", "Pragma" and "Set-cookie" headers in server
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008225 response to check if there's a risk of caching a cookie on a client-side
8226 proxy. When this option is enabled, the only responses which can be delivered
Willy Tarreau198a7442008-01-17 12:05:32 +01008227 to the client are :
Davor Ocelice9ed2812017-12-25 17:49:28 +01008228 - all those without "Set-Cookie" header;
Willy Tarreauc55ddce2017-12-21 11:41:38 +01008229 - all those with a return code other than 200, 203, 204, 206, 300, 301,
8230 404, 405, 410, 414, 501, provided that the server has not set a
Davor Ocelice9ed2812017-12-25 17:49:28 +01008231 "Cache-control: public" header field;
Willy Tarreau24ea0bc2017-12-21 11:32:55 +01008232 - all those that result from a request using a method other than GET, HEAD,
8233 OPTIONS, TRACE, provided that the server has not set a 'Cache-Control:
Davor Ocelice9ed2812017-12-25 17:49:28 +01008234 public' header field;
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008235 - those with a 'Pragma: no-cache' header
8236 - those with a 'Cache-control: private' header
8237 - those with a 'Cache-control: no-store' header
8238 - those with a 'Cache-control: max-age=0' header
8239 - those with a 'Cache-control: s-maxage=0' header
8240 - those with a 'Cache-control: no-cache' header
8241 - those with a 'Cache-control: no-cache="set-cookie"' header
8242 - those with a 'Cache-control: no-cache="set-cookie,' header
8243 (allowing other fields after set-cookie)
8244
8245 If a response doesn't respect these requirements, then it will be blocked
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02008246 just as if it was from an "http-response deny" rule, with an "HTTP 502 bad
8247 gateway". The session state shows "PH--" meaning that the proxy blocked the
8248 response during headers processing. Additionally, an alert will be sent in
8249 the logs so that admins are informed that there's something to be fixed.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008250
8251 Due to the high impact on the application, the application should be tested
8252 in depth with the option enabled before going to production. It is also a
Willy Tarreaud2a4aa22008-01-31 15:28:22 +01008253 good practice to always activate it during tests, even if it is not used in
Davor Ocelice9ed2812017-12-25 17:49:28 +01008254 production, as it will report potentially dangerous application behaviors.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008255
8256 If this option has been enabled in a "defaults" section, it can be disabled
8257 in a specific instance by prepending the "no" keyword before it.
8258
8259
8260option clitcpka
8261no option clitcpka
8262 Enable or disable the sending of TCP keepalive packets on the client side
8263 May be used in sections : defaults | frontend | listen | backend
8264 yes | yes | yes | no
8265 Arguments : none
8266
8267 When there is a firewall or any session-aware component between a client and
8268 a server, and when the protocol involves very long sessions with long idle
Davor Ocelice9ed2812017-12-25 17:49:28 +01008269 periods (e.g. remote desktops), there is a risk that one of the intermediate
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008270 components decides to expire a session which has remained idle for too long.
8271
8272 Enabling socket-level TCP keep-alives makes the system regularly send packets
8273 to the other end of the connection, leaving it active. The delay between
8274 keep-alive probes is controlled by the system only and depends both on the
8275 operating system and its tuning parameters.
8276
8277 It is important to understand that keep-alive packets are neither emitted nor
8278 received at the application level. It is only the network stacks which sees
8279 them. For this reason, even if one side of the proxy already uses keep-alives
8280 to maintain its connection alive, those keep-alive packets will not be
8281 forwarded to the other side of the proxy.
8282
8283 Please note that this has nothing to do with HTTP keep-alive.
8284
8285 Using option "clitcpka" enables the emission of TCP keep-alive probes on the
8286 client side of a connection, which should help when session expirations are
8287 noticed between HAProxy and a client.
8288
8289 If this option has been enabled in a "defaults" section, it can be disabled
8290 in a specific instance by prepending the "no" keyword before it.
8291
8292 See also : "option srvtcpka", "option tcpka"
8293
8294
Willy Tarreau0ba27502007-12-24 16:55:16 +01008295option contstats
8296 Enable continuous traffic statistics updates
8297 May be used in sections : defaults | frontend | listen | backend
8298 yes | yes | yes | no
8299 Arguments : none
8300
8301 By default, counters used for statistics calculation are incremented
8302 only when a session finishes. It works quite well when serving small
8303 objects, but with big ones (for example large images or archives) or
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008304 with A/V streaming, a graph generated from HAProxy counters looks like
Willy Tarreaudef0d222016-11-08 22:03:00 +01008305 a hedgehog. With this option enabled counters get incremented frequently
8306 along the session, typically every 5 seconds, which is often enough to
8307 produce clean graphs. Recounting touches a hotpath directly so it is not
8308 not enabled by default, as it can cause a lot of wakeups for very large
8309 session counts and cause a small performance drop.
Willy Tarreau0ba27502007-12-24 16:55:16 +01008310
Christopher Faulet89aed322020-06-02 17:33:56 +02008311option disable-h2-upgrade
8312no option disable-h2-upgrade
8313 Enable or disable the implicit HTTP/2 upgrade from an HTTP/1.x client
8314 connection.
8315 May be used in sections : defaults | frontend | listen | backend
8316 yes | yes | yes | no
8317 Arguments : none
8318
8319 By default, HAProxy is able to implicitly upgrade an HTTP/1.x client
8320 connection to an HTTP/2 connection if the first request it receives from a
8321 given HTTP connection matches the HTTP/2 connection preface (i.e. the string
8322 "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n"). This way, it is possible to support
Christopher Faulet982e17d2021-03-26 14:44:18 +01008323 HTTP/1.x and HTTP/2 clients on a non-SSL connections. This option must be
8324 used to disable the implicit upgrade. Note this implicit upgrade is only
8325 supported for HTTP proxies, thus this option too. Note also it is possible to
8326 force the HTTP/2 on clear connections by specifying "proto h2" on the bind
8327 line. Finally, this option is applied on all bind lines. To disable implicit
8328 HTTP/2 upgrades for a specific bind line, it is possible to use "proto h1".
Christopher Faulet89aed322020-06-02 17:33:56 +02008329
8330 If this option has been enabled in a "defaults" section, it can be disabled
8331 in a specific instance by prepending the "no" keyword before it.
Willy Tarreau0ba27502007-12-24 16:55:16 +01008332
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +02008333option dontlog-normal
8334no option dontlog-normal
8335 Enable or disable logging of normal, successful connections
8336 May be used in sections : defaults | frontend | listen | backend
8337 yes | yes | yes | no
8338 Arguments : none
8339
8340 There are large sites dealing with several thousand connections per second
8341 and for which logging is a major pain. Some of them are even forced to turn
8342 logs off and cannot debug production issues. Setting this option ensures that
8343 normal connections, those which experience no error, no timeout, no retry nor
8344 redispatch, will not be logged. This leaves disk space for anomalies. In HTTP
8345 mode, the response status code is checked and return codes 5xx will still be
8346 logged.
8347
8348 It is strongly discouraged to use this option as most of the time, the key to
8349 complex issues is in the normal logs which will not be logged here. If you
8350 need to separate logs, see the "log-separate-errors" option instead.
8351
Willy Tarreauc57f0e22009-05-10 13:12:33 +02008352 See also : "log", "dontlognull", "log-separate-errors" and section 8 about
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +02008353 logging.
8354
8355
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008356option dontlognull
8357no option dontlognull
8358 Enable or disable logging of null connections
8359 May be used in sections : defaults | frontend | listen | backend
8360 yes | yes | yes | no
8361 Arguments : none
8362
8363 In certain environments, there are components which will regularly connect to
8364 various systems to ensure that they are still alive. It can be the case from
8365 another load balancer as well as from monitoring systems. By default, even a
8366 simple port probe or scan will produce a log. If those connections pollute
8367 the logs too much, it is possible to enable option "dontlognull" to indicate
8368 that a connection on which no data has been transferred will not be logged,
Willy Tarreau0f228a02015-05-01 15:37:53 +02008369 which typically corresponds to those probes. Note that errors will still be
8370 returned to the client and accounted for in the stats. If this is not what is
8371 desired, option http-ignore-probes can be used instead.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008372
8373 It is generally recommended not to use this option in uncontrolled
Davor Ocelice9ed2812017-12-25 17:49:28 +01008374 environments (e.g. internet), otherwise scans and other malicious activities
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008375 would not be logged.
8376
8377 If this option has been enabled in a "defaults" section, it can be disabled
8378 in a specific instance by prepending the "no" keyword before it.
8379
Willy Tarreau9e9919d2020-10-14 15:55:23 +02008380 See also : "log", "http-ignore-probes", "monitor-uri", and
Willy Tarreau0f228a02015-05-01 15:37:53 +02008381 section 8 about logging.
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008382
Willy Tarreaubf1f8162007-12-28 17:42:56 +01008383
Willy Tarreau87cf5142011-08-19 22:57:24 +02008384option forwardfor [ except <network> ] [ header <name> ] [ if-none ]
Willy Tarreauc27debf2008-01-06 08:57:02 +01008385 Enable insertion of the X-Forwarded-For header to requests sent to servers
8386 May be used in sections : defaults | frontend | listen | backend
8387 yes | yes | yes | yes
8388 Arguments :
8389 <network> is an optional argument used to disable this option for sources
8390 matching <network>
Ross Westaf72a1d2008-08-03 10:51:45 +02008391 <name> an optional argument to specify a different "X-Forwarded-For"
Willy Tarreaud72758d2010-01-12 10:42:19 +01008392 header name.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008393
8394 Since HAProxy works in reverse-proxy mode, the servers see its IP address as
8395 their client address. This is sometimes annoying when the client's IP address
8396 is expected in server logs. To solve this problem, the well-known HTTP header
8397 "X-Forwarded-For" may be added by HAProxy to all requests sent to the server.
8398 This header contains a value representing the client's IP address. Since this
8399 header is always appended at the end of the existing header list, the server
8400 must be configured to always use the last occurrence of this header only. See
Ross Westaf72a1d2008-08-03 10:51:45 +02008401 the server's manual to find how to enable use of this standard header. Note
8402 that only the last occurrence of the header must be used, since it is really
8403 possible that the client has already brought one.
8404
Willy Tarreaud72758d2010-01-12 10:42:19 +01008405 The keyword "header" may be used to supply a different header name to replace
Ross Westaf72a1d2008-08-03 10:51:45 +02008406 the default "X-Forwarded-For". This can be useful where you might already
Davor Ocelice9ed2812017-12-25 17:49:28 +01008407 have a "X-Forwarded-For" header from a different application (e.g. stunnel),
Willy Tarreaud72758d2010-01-12 10:42:19 +01008408 and you need preserve it. Also if your backend server doesn't use the
Davor Ocelice9ed2812017-12-25 17:49:28 +01008409 "X-Forwarded-For" header and requires different one (e.g. Zeus Web Servers
Ross Westaf72a1d2008-08-03 10:51:45 +02008410 require "X-Cluster-Client-IP").
Willy Tarreauc27debf2008-01-06 08:57:02 +01008411
8412 Sometimes, a same HAProxy instance may be shared between a direct client
8413 access and a reverse-proxy access (for instance when an SSL reverse-proxy is
8414 used to decrypt HTTPS traffic). It is possible to disable the addition of the
8415 header for a known source address or network by adding the "except" keyword
8416 followed by the network address. In this case, any source IP matching the
8417 network will not cause an addition of this header. Most common uses are with
Christopher Faulet5d1def62021-02-26 09:19:15 +01008418 private networks or 127.0.0.1. IPv4 and IPv6 are both supported.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008419
Willy Tarreau87cf5142011-08-19 22:57:24 +02008420 Alternatively, the keyword "if-none" states that the header will only be
8421 added if it is not present. This should only be used in perfectly trusted
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008422 environment, as this might cause a security issue if headers reaching HAProxy
Willy Tarreau87cf5142011-08-19 22:57:24 +02008423 are under the control of the end-user.
8424
Willy Tarreauc27debf2008-01-06 08:57:02 +01008425 This option may be specified either in the frontend or in the backend. If at
Ross Westaf72a1d2008-08-03 10:51:45 +02008426 least one of them uses it, the header will be added. Note that the backend's
8427 setting of the header subargument takes precedence over the frontend's if
Willy Tarreau87cf5142011-08-19 22:57:24 +02008428 both are defined. In the case of the "if-none" argument, if at least one of
8429 the frontend or the backend does not specify it, it wants the addition to be
8430 mandatory, so it wins.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008431
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +02008432 Example :
Willy Tarreauc27debf2008-01-06 08:57:02 +01008433 # Public HTTP address also used by stunnel on the same machine
8434 frontend www
8435 mode http
8436 option forwardfor except 127.0.0.1 # stunnel already adds the header
8437
Ross Westaf72a1d2008-08-03 10:51:45 +02008438 # Those servers want the IP Address in X-Client
8439 backend www
8440 mode http
8441 option forwardfor header X-Client
8442
Willy Tarreau87cf5142011-08-19 22:57:24 +02008443 See also : "option httpclose", "option http-server-close",
Christopher Faulet315b39c2018-09-21 16:26:19 +02008444 "option http-keep-alive"
Willy Tarreauc27debf2008-01-06 08:57:02 +01008445
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008446
Christopher Faulet98fbe952019-07-22 16:18:24 +02008447option h1-case-adjust-bogus-client
8448no option h1-case-adjust-bogus-client
8449 Enable or disable the case adjustment of HTTP/1 headers sent to bogus clients
8450 May be used in sections : defaults | frontend | listen | backend
8451 yes | yes | yes | no
8452 Arguments : none
8453
8454 There is no standard case for header names because, as stated in RFC7230,
8455 they are case-insensitive. So applications must handle them in a case-
8456 insensitive manner. But some bogus applications violate the standards and
8457 erroneously rely on the cases most commonly used by browsers. This problem
8458 becomes critical with HTTP/2 because all header names must be exchanged in
8459 lower case, and HAProxy follows the same convention. All header names are
8460 sent in lower case to clients and servers, regardless of the HTTP version.
8461
8462 When HAProxy receives an HTTP/1 response, its header names are converted to
8463 lower case and manipulated and sent this way to the clients. If a client is
8464 known to violate the HTTP standards and to fail to process a response coming
8465 from HAProxy, it is possible to transform the lower case header names to a
8466 different format when the response is formatted and sent to the client, by
8467 enabling this option and specifying the list of headers to be reformatted
8468 using the global directives "h1-case-adjust" or "h1-case-adjust-file". This
8469 must only be a temporary workaround for the time it takes the client to be
8470 fixed, because clients which require such workarounds might be vulnerable to
8471 content smuggling attacks and must absolutely be fixed.
8472
8473 Please note that this option will not affect standards-compliant clients.
8474
8475 If this option has been enabled in a "defaults" section, it can be disabled
8476 in a specific instance by prepending the "no" keyword before it.
8477
8478 See also: "option h1-case-adjust-bogus-server", "h1-case-adjust",
8479 "h1-case-adjust-file".
8480
8481
8482option h1-case-adjust-bogus-server
8483no option h1-case-adjust-bogus-server
8484 Enable or disable the case adjustment of HTTP/1 headers sent to bogus servers
8485 May be used in sections : defaults | frontend | listen | backend
8486 yes | no | yes | yes
8487 Arguments : none
8488
8489 There is no standard case for header names because, as stated in RFC7230,
8490 they are case-insensitive. So applications must handle them in a case-
8491 insensitive manner. But some bogus applications violate the standards and
8492 erroneously rely on the cases most commonly used by browsers. This problem
8493 becomes critical with HTTP/2 because all header names must be exchanged in
8494 lower case, and HAProxy follows the same convention. All header names are
8495 sent in lower case to clients and servers, regardless of the HTTP version.
8496
8497 When HAProxy receives an HTTP/1 request, its header names are converted to
8498 lower case and manipulated and sent this way to the servers. If a server is
8499 known to violate the HTTP standards and to fail to process a request coming
8500 from HAProxy, it is possible to transform the lower case header names to a
8501 different format when the request is formatted and sent to the server, by
8502 enabling this option and specifying the list of headers to be reformatted
8503 using the global directives "h1-case-adjust" or "h1-case-adjust-file". This
8504 must only be a temporary workaround for the time it takes the server to be
8505 fixed, because servers which require such workarounds might be vulnerable to
8506 content smuggling attacks and must absolutely be fixed.
8507
8508 Please note that this option will not affect standards-compliant servers.
8509
8510 If this option has been enabled in a "defaults" section, it can be disabled
8511 in a specific instance by prepending the "no" keyword before it.
8512
8513 See also: "option h1-case-adjust-bogus-client", "h1-case-adjust",
8514 "h1-case-adjust-file".
8515
8516
Willy Tarreau9fbe18e2015-05-01 22:42:08 +02008517option http-buffer-request
8518no option http-buffer-request
8519 Enable or disable waiting for whole HTTP request body before proceeding
8520 May be used in sections : defaults | frontend | listen | backend
8521 yes | yes | yes | yes
8522 Arguments : none
8523
8524 It is sometimes desirable to wait for the body of an HTTP request before
8525 taking a decision. This is what is being done by "balance url_param" for
8526 example. The first use case is to buffer requests from slow clients before
8527 connecting to the server. Another use case consists in taking the routing
8528 decision based on the request body's contents. This option placed in a
8529 frontend or backend forces the HTTP processing to wait until either the whole
Christopher Faulet6db8a2e2019-11-19 16:27:25 +01008530 body is received or the request buffer is full. It can have undesired side
8531 effects with some applications abusing HTTP by expecting unbuffered
8532 transmissions between the frontend and the backend, so this should definitely
8533 not be used by default.
Willy Tarreau9fbe18e2015-05-01 22:42:08 +02008534
Christopher Faulet021a8e42021-03-29 10:46:38 +02008535 See also : "option http-no-delay", "timeout http-request",
8536 "http-request wait-for-body"
Willy Tarreau9fbe18e2015-05-01 22:42:08 +02008537
8538
Willy Tarreau0f228a02015-05-01 15:37:53 +02008539option http-ignore-probes
8540no option http-ignore-probes
8541 Enable or disable logging of null connections and request timeouts
8542 May be used in sections : defaults | frontend | listen | backend
8543 yes | yes | yes | no
8544 Arguments : none
8545
8546 Recently some browsers started to implement a "pre-connect" feature
8547 consisting in speculatively connecting to some recently visited web sites
8548 just in case the user would like to visit them. This results in many
8549 connections being established to web sites, which end up in 408 Request
8550 Timeout if the timeout strikes first, or 400 Bad Request when the browser
8551 decides to close them first. These ones pollute the log and feed the error
8552 counters. There was already "option dontlognull" but it's insufficient in
8553 this case. Instead, this option does the following things :
8554 - prevent any 400/408 message from being sent to the client if nothing
Davor Ocelice9ed2812017-12-25 17:49:28 +01008555 was received over a connection before it was closed;
8556 - prevent any log from being emitted in this situation;
Willy Tarreau0f228a02015-05-01 15:37:53 +02008557 - prevent any error counter from being incremented
8558
8559 That way the empty connection is silently ignored. Note that it is better
8560 not to use this unless it is clear that it is needed, because it will hide
8561 real problems. The most common reason for not receiving a request and seeing
8562 a 408 is due to an MTU inconsistency between the client and an intermediary
8563 element such as a VPN, which blocks too large packets. These issues are
8564 generally seen with POST requests as well as GET with large cookies. The logs
8565 are often the only way to detect them.
8566
8567 If this option has been enabled in a "defaults" section, it can be disabled
8568 in a specific instance by prepending the "no" keyword before it.
8569
8570 See also : "log", "dontlognull", "errorfile", and section 8 about logging.
8571
8572
Willy Tarreau16bfb022010-01-16 19:48:41 +01008573option http-keep-alive
8574no option http-keep-alive
8575 Enable or disable HTTP keep-alive from client to server
8576 May be used in sections : defaults | frontend | listen | backend
8577 yes | yes | yes | yes
8578 Arguments : none
8579
Willy Tarreau70dffda2014-01-30 03:07:23 +01008580 By default HAProxy operates in keep-alive mode with regards to persistent
8581 connections: for each connection it processes each request and response, and
Christopher Faulet315b39c2018-09-21 16:26:19 +02008582 leaves the connection idle on both sides between the end of a response and
8583 the start of a new request. This mode may be changed by several options such
Christopher Faulet159e6672019-07-16 15:09:52 +02008584 as "option http-server-close" or "option httpclose". This option allows to
8585 set back the keep-alive mode, which can be useful when another mode was used
8586 in a defaults section.
Willy Tarreau70dffda2014-01-30 03:07:23 +01008587
8588 Setting "option http-keep-alive" enables HTTP keep-alive mode on the client-
8589 and server- sides. This provides the lowest latency on the client side (slow
Willy Tarreau16bfb022010-01-16 19:48:41 +01008590 network) and the fastest session reuse on the server side at the expense
8591 of maintaining idle connections to the servers. In general, it is possible
8592 with this option to achieve approximately twice the request rate that the
8593 "http-server-close" option achieves on small objects. There are mainly two
8594 situations where this option may be useful :
8595
8596 - when the server is non-HTTP compliant and authenticates the connection
Davor Ocelice9ed2812017-12-25 17:49:28 +01008597 instead of requests (e.g. NTLM authentication)
Willy Tarreau16bfb022010-01-16 19:48:41 +01008598
8599 - when the cost of establishing the connection to the server is significant
8600 compared to the cost of retrieving the associated object from the server.
8601
8602 This last case can happen when the server is a fast static server of cache.
8603 In this case, the server will need to be properly tuned to support high enough
8604 connection counts because connections will last until the client sends another
8605 request.
8606
8607 If the client request has to go to another backend or another server due to
8608 content switching or the load balancing algorithm, the idle connection will
Willy Tarreau9420b122013-12-15 18:58:25 +01008609 immediately be closed and a new one re-opened. Option "prefer-last-server" is
8610 available to try optimize server selection so that if the server currently
8611 attached to an idle connection is usable, it will be used.
Willy Tarreau16bfb022010-01-16 19:48:41 +01008612
Willy Tarreau16bfb022010-01-16 19:48:41 +01008613 At the moment, logs will not indicate whether requests came from the same
8614 session or not. The accept date reported in the logs corresponds to the end
8615 of the previous request, and the request time corresponds to the time spent
8616 waiting for a new request. The keep-alive request time is still bound to the
8617 timeout defined by "timeout http-keep-alive" or "timeout http-request" if
8618 not set.
8619
Christopher Faulet159e6672019-07-16 15:09:52 +02008620 This option disables and replaces any previous "option httpclose" or "option
8621 http-server-close". When backend and frontend options differ, all of these 4
8622 options have precedence over "option http-keep-alive".
Willy Tarreau16bfb022010-01-16 19:48:41 +01008623
Christopher Faulet315b39c2018-09-21 16:26:19 +02008624 See also : "option httpclose",, "option http-server-close",
Willy Tarreau9420b122013-12-15 18:58:25 +01008625 "option prefer-last-server", "option http-pretend-keepalive",
Frédéric Lécaille93d33162019-03-06 09:35:59 +01008626 and "1.1. The HTTP transaction model".
Willy Tarreau16bfb022010-01-16 19:48:41 +01008627
8628
Willy Tarreau96e31212011-05-30 18:10:30 +02008629option http-no-delay
8630no option http-no-delay
8631 Instruct the system to favor low interactive delays over performance in HTTP
8632 May be used in sections : defaults | frontend | listen | backend
8633 yes | yes | yes | yes
8634 Arguments : none
8635
8636 In HTTP, each payload is unidirectional and has no notion of interactivity.
8637 Any agent is expected to queue data somewhat for a reasonably low delay.
8638 There are some very rare server-to-server applications that abuse the HTTP
8639 protocol and expect the payload phase to be highly interactive, with many
8640 interleaved data chunks in both directions within a single request. This is
8641 absolutely not supported by the HTTP specification and will not work across
8642 most proxies or servers. When such applications attempt to do this through
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008643 HAProxy, it works but they will experience high delays due to the network
Willy Tarreau96e31212011-05-30 18:10:30 +02008644 optimizations which favor performance by instructing the system to wait for
8645 enough data to be available in order to only send full packets. Typical
8646 delays are around 200 ms per round trip. Note that this only happens with
8647 abnormal uses. Normal uses such as CONNECT requests nor WebSockets are not
8648 affected.
8649
8650 When "option http-no-delay" is present in either the frontend or the backend
8651 used by a connection, all such optimizations will be disabled in order to
8652 make the exchanges as fast as possible. Of course this offers no guarantee on
8653 the functionality, as it may break at any other place. But if it works via
8654 HAProxy, it will work as fast as possible. This option should never be used
8655 by default, and should never be used at all unless such a buggy application
8656 is discovered. The impact of using this option is an increase of bandwidth
8657 usage and CPU usage, which may significantly lower performance in high
8658 latency environments.
8659
Willy Tarreau9fbe18e2015-05-01 22:42:08 +02008660 See also : "option http-buffer-request"
8661
Willy Tarreau96e31212011-05-30 18:10:30 +02008662
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008663option http-pretend-keepalive
8664no option http-pretend-keepalive
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008665 Define whether HAProxy will announce keepalive to the server or not
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008666 May be used in sections : defaults | frontend | listen | backend
Christopher Faulet98db9762018-09-21 10:25:19 +02008667 yes | no | yes | yes
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008668 Arguments : none
8669
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008670 When running with "option http-server-close" or "option httpclose", HAProxy
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008671 adds a "Connection: close" header to the request forwarded to the server.
8672 Unfortunately, when some servers see this header, they automatically refrain
8673 from using the chunked encoding for responses of unknown length, while this
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008674 is totally unrelated. The immediate effect is that this prevents HAProxy from
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008675 maintaining the client connection alive. A second effect is that a client or
8676 a cache could receive an incomplete response without being aware of it, and
8677 consider the response complete.
8678
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008679 By setting "option http-pretend-keepalive", HAProxy will make the server
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008680 believe it will keep the connection alive. The server will then not fall back
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008681 to the abnormal undesired above. When HAProxy gets the whole response, it
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008682 will close the connection with the server just as it would do with the
Christopher Faulet315b39c2018-09-21 16:26:19 +02008683 "option httpclose". That way the client gets a normal response and the
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008684 connection is correctly closed on the server side.
8685
8686 It is recommended not to enable this option by default, because most servers
8687 will more efficiently close the connection themselves after the last packet,
8688 and release its buffers slightly earlier. Also, the added packet on the
8689 network could slightly reduce the overall peak performance. However it is
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008690 worth noting that when this option is enabled, HAProxy will have slightly
8691 less work to do. So if HAProxy is the bottleneck on the whole architecture,
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008692 enabling this option might save a few CPU cycles.
8693
Christopher Faulet98db9762018-09-21 10:25:19 +02008694 This option may be set in backend and listen sections. Using it in a frontend
8695 section will be ignored and a warning will be reported during startup. It is
8696 a backend related option, so there is no real reason to set it on a
8697 frontend. This option may be combined with "option httpclose", which will
8698 cause keepalive to be announced to the server and close to be announced to
8699 the client. This practice is discouraged though.
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008700
8701 If this option has been enabled in a "defaults" section, it can be disabled
8702 in a specific instance by prepending the "no" keyword before it.
8703
Christopher Faulet315b39c2018-09-21 16:26:19 +02008704 See also : "option httpclose", "option http-server-close", and
Willy Tarreau16bfb022010-01-16 19:48:41 +01008705 "option http-keep-alive"
Willy Tarreau8a8e1d92010-04-05 16:15:16 +02008706
Willy Tarreauc27debf2008-01-06 08:57:02 +01008707
Willy Tarreaub608feb2010-01-02 22:47:18 +01008708option http-server-close
8709no option http-server-close
8710 Enable or disable HTTP connection closing on the server side
8711 May be used in sections : defaults | frontend | listen | backend
8712 yes | yes | yes | yes
8713 Arguments : none
8714
Willy Tarreau70dffda2014-01-30 03:07:23 +01008715 By default HAProxy operates in keep-alive mode with regards to persistent
8716 connections: for each connection it processes each request and response, and
8717 leaves the connection idle on both sides between the end of a response and
8718 the start of a new request. This mode may be changed by several options such
Christopher Faulet159e6672019-07-16 15:09:52 +02008719 as "option http-server-close" or "option httpclose". Setting "option
8720 http-server-close" enables HTTP connection-close mode on the server side
8721 while keeping the ability to support HTTP keep-alive and pipelining on the
8722 client side. This provides the lowest latency on the client side (slow
8723 network) and the fastest session reuse on the server side to save server
8724 resources, similarly to "option httpclose". It also permits non-keepalive
8725 capable servers to be served in keep-alive mode to the clients if they
8726 conform to the requirements of RFC7230. Please note that some servers do not
8727 always conform to those requirements when they see "Connection: close" in the
8728 request. The effect will be that keep-alive will never be used. A workaround
8729 consists in enabling "option http-pretend-keepalive".
Willy Tarreaub608feb2010-01-02 22:47:18 +01008730
8731 At the moment, logs will not indicate whether requests came from the same
8732 session or not. The accept date reported in the logs corresponds to the end
8733 of the previous request, and the request time corresponds to the time spent
8734 waiting for a new request. The keep-alive request time is still bound to the
Willy Tarreaub16a5742010-01-10 14:46:16 +01008735 timeout defined by "timeout http-keep-alive" or "timeout http-request" if
8736 not set.
Willy Tarreaub608feb2010-01-02 22:47:18 +01008737
8738 This option may be set both in a frontend and in a backend. It is enabled if
8739 at least one of the frontend or backend holding a connection has it enabled.
Christopher Faulet159e6672019-07-16 15:09:52 +02008740 It disables and replaces any previous "option httpclose" or "option
8741 http-keep-alive". Please check section 4 ("Proxies") to see how this option
8742 combines with others when frontend and backend options differ.
Willy Tarreaub608feb2010-01-02 22:47:18 +01008743
8744 If this option has been enabled in a "defaults" section, it can be disabled
8745 in a specific instance by prepending the "no" keyword before it.
8746
Christopher Faulet315b39c2018-09-21 16:26:19 +02008747 See also : "option httpclose", "option http-pretend-keepalive",
8748 "option http-keep-alive", and "1.1. The HTTP transaction model".
Willy Tarreaub608feb2010-01-02 22:47:18 +01008749
Willy Tarreau88d349d2010-01-25 12:15:43 +01008750option http-use-proxy-header
Cyril Bontéf0c60612010-02-06 14:44:47 +01008751no option http-use-proxy-header
Willy Tarreau88d349d2010-01-25 12:15:43 +01008752 Make use of non-standard Proxy-Connection header instead of Connection
8753 May be used in sections : defaults | frontend | listen | backend
8754 yes | yes | yes | no
8755 Arguments : none
8756
Lukas Tribus23953682017-04-28 13:24:30 +00008757 While RFC7230 explicitly states that HTTP/1.1 agents must use the
Willy Tarreau88d349d2010-01-25 12:15:43 +01008758 Connection header to indicate their wish of persistent or non-persistent
8759 connections, both browsers and proxies ignore this header for proxied
8760 connections and make use of the undocumented, non-standard Proxy-Connection
8761 header instead. The issue begins when trying to put a load balancer between
8762 browsers and such proxies, because there will be a difference between what
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008763 HAProxy understands and what the client and the proxy agree on.
Willy Tarreau88d349d2010-01-25 12:15:43 +01008764
Daniel Corbett9f0843f2021-05-08 10:50:37 -04008765 By setting this option in a frontend, HAProxy can automatically switch to use
Willy Tarreau88d349d2010-01-25 12:15:43 +01008766 that non-standard header if it sees proxied requests. A proxied request is
Lukas Tribusf01a9cd2016-02-03 18:09:37 +01008767 defined here as one where the URI begins with neither a '/' nor a '*'. This
8768 is incompatible with the HTTP tunnel mode. Note that this option can only be
8769 specified in a frontend and will affect the request along its whole life.
Willy Tarreau88d349d2010-01-25 12:15:43 +01008770
Willy Tarreau844a7e72010-01-31 21:46:18 +01008771 Also, when this option is set, a request which requires authentication will
8772 automatically switch to use proxy authentication headers if it is itself a
8773 proxied request. That makes it possible to check or enforce authentication in
8774 front of an existing proxy.
8775
Willy Tarreau88d349d2010-01-25 12:15:43 +01008776 This option should normally never be used, except in front of a proxy.
8777
Christopher Faulet315b39c2018-09-21 16:26:19 +02008778 See also : "option httpclose", and "option http-server-close".
Willy Tarreau88d349d2010-01-25 12:15:43 +01008779
Willy Tarreaud63335a2010-02-26 12:56:52 +01008780option httpchk
8781option httpchk <uri>
8782option httpchk <method> <uri>
8783option httpchk <method> <uri> <version>
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02008784 Enables HTTP protocol to check on the servers health
Willy Tarreaud63335a2010-02-26 12:56:52 +01008785 May be used in sections : defaults | frontend | listen | backend
8786 yes | no | yes | yes
8787 Arguments :
8788 <method> is the optional HTTP method used with the requests. When not set,
8789 the "OPTIONS" method is used, as it generally requires low server
8790 processing and is easy to filter out from the logs. Any method
8791 may be used, though it is not recommended to invent non-standard
8792 ones.
8793
8794 <uri> is the URI referenced in the HTTP requests. It defaults to " / "
8795 which is accessible by default on almost any server, but may be
8796 changed to any other URI. Query strings are permitted.
8797
8798 <version> is the optional HTTP version string. It defaults to "HTTP/1.0"
8799 but some servers might behave incorrectly in HTTP 1.0, so turning
8800 it to HTTP/1.1 may sometimes help. Note that the Host field is
Christopher Faulet8acb1282020-04-09 08:44:06 +02008801 mandatory in HTTP/1.1, use "http-check send" directive to add it.
Willy Tarreaud63335a2010-02-26 12:56:52 +01008802
8803 By default, server health checks only consist in trying to establish a TCP
8804 connection. When "option httpchk" is specified, a complete HTTP request is
8805 sent once the TCP connection is established, and responses 2xx and 3xx are
8806 considered valid, while all other ones indicate a server failure, including
8807 the lack of any response.
8808
Christopher Faulete5870d82020-04-15 11:32:03 +02008809 Combined with "http-check" directives, it is possible to customize the
8810 request sent during the HTTP health checks or the matching rules on the
8811 response. It is also possible to configure a send/expect sequence, just like
8812 with the directive "tcp-check" for TCP health checks.
8813
8814 The server configuration is used by default to open connections to perform
8815 HTTP health checks. By it is also possible to overwrite server parameters
8816 using "http-check connect" rules.
Willy Tarreaud63335a2010-02-26 12:56:52 +01008817
Christopher Faulete5870d82020-04-15 11:32:03 +02008818 "httpchk" option does not necessarily require an HTTP backend, it also works
8819 with plain TCP backends. This is particularly useful to check simple scripts
Christopher Faulet14cd3162020-04-16 14:50:06 +02008820 bound to some dedicated ports using the inetd daemon. However, it will always
Daniel Corbett67a82712020-07-06 23:01:19 -04008821 internally relies on an HTX multiplexer. Thus, it means the request
Christopher Faulet14cd3162020-04-16 14:50:06 +02008822 formatting and the response parsing will be strict.
Willy Tarreaud63335a2010-02-26 12:56:52 +01008823
Christopher Faulet8acb1282020-04-09 08:44:06 +02008824 Note : For a while, there was no way to add headers or body in the request
8825 used for HTTP health checks. So a workaround was to hide it at the end
8826 of the version string with a "\r\n" after the version. It is now
8827 deprecated. The directive "http-check send" must be used instead.
8828
Willy Tarreaud63335a2010-02-26 12:56:52 +01008829 Examples :
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02008830 # Relay HTTPS traffic to Apache instance and check service availability
8831 # using HTTP request "OPTIONS * HTTP/1.1" on port 80.
8832 backend https_relay
8833 mode tcp
8834 option httpchk OPTIONS * HTTP/1.1
8835 http-check send hdr Host www
8836 server apache1 192.168.1.1:443 check port 80
Willy Tarreaud63335a2010-02-26 12:56:52 +01008837
Simon Hormanafc47ee2013-11-25 10:46:35 +09008838 See also : "option ssl-hello-chk", "option smtpchk", "option mysql-check",
8839 "option pgsql-check", "http-check" and the "check", "port" and
8840 "inter" server options.
Willy Tarreaud63335a2010-02-26 12:56:52 +01008841
8842
Willy Tarreauc27debf2008-01-06 08:57:02 +01008843option httpclose
8844no option httpclose
Christopher Faulet315b39c2018-09-21 16:26:19 +02008845 Enable or disable HTTP connection closing
Willy Tarreauc27debf2008-01-06 08:57:02 +01008846 May be used in sections : defaults | frontend | listen | backend
8847 yes | yes | yes | yes
8848 Arguments : none
8849
Willy Tarreau70dffda2014-01-30 03:07:23 +01008850 By default HAProxy operates in keep-alive mode with regards to persistent
8851 connections: for each connection it processes each request and response, and
8852 leaves the connection idle on both sides between the end of a response and
8853 the start of a new request. This mode may be changed by several options such
Christopher Faulet159e6672019-07-16 15:09:52 +02008854 as "option http-server-close" or "option httpclose".
Willy Tarreau70dffda2014-01-30 03:07:23 +01008855
Christopher Faulet315b39c2018-09-21 16:26:19 +02008856 If "option httpclose" is set, HAProxy will close connections with the server
8857 and the client as soon as the request and the response are received. It will
John Roeslerfb2fce12019-07-10 15:45:51 -05008858 also check if a "Connection: close" header is already set in each direction,
Christopher Faulet315b39c2018-09-21 16:26:19 +02008859 and will add one if missing. Any "Connection" header different from "close"
8860 will also be removed.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008861
Christopher Faulet315b39c2018-09-21 16:26:19 +02008862 This option may also be combined with "option http-pretend-keepalive", which
8863 will disable sending of the "Connection: close" header, but will still cause
8864 the connection to be closed once the whole response is received.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008865
8866 This option may be set both in a frontend and in a backend. It is enabled if
8867 at least one of the frontend or backend holding a connection has it enabled.
Christopher Faulet159e6672019-07-16 15:09:52 +02008868 It disables and replaces any previous "option http-server-close" or "option
8869 http-keep-alive". Please check section 4 ("Proxies") to see how this option
8870 combines with others when frontend and backend options differ.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008871
8872 If this option has been enabled in a "defaults" section, it can be disabled
8873 in a specific instance by prepending the "no" keyword before it.
8874
Christopher Faulet315b39c2018-09-21 16:26:19 +02008875 See also : "option http-server-close" and "1.1. The HTTP transaction model".
Willy Tarreauc27debf2008-01-06 08:57:02 +01008876
8877
Emeric Brun3a058f32009-06-30 18:26:00 +02008878option httplog [ clf ]
Willy Tarreauc27debf2008-01-06 08:57:02 +01008879 Enable logging of HTTP request, session state and timers
8880 May be used in sections : defaults | frontend | listen | backend
Tim Duesterhus9ad9f352018-02-05 20:52:27 +01008881 yes | yes | yes | no
Emeric Brun3a058f32009-06-30 18:26:00 +02008882 Arguments :
8883 clf if the "clf" argument is added, then the output format will be
8884 the CLF format instead of HAProxy's default HTTP format. You can
8885 use this when you need to feed HAProxy's logs through a specific
Davor Ocelice9ed2812017-12-25 17:49:28 +01008886 log analyzer which only support the CLF format and which is not
Emeric Brun3a058f32009-06-30 18:26:00 +02008887 extensible.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008888
8889 By default, the log output format is very poor, as it only contains the
8890 source and destination addresses, and the instance name. By specifying
8891 "option httplog", each log line turns into a much richer format including,
8892 but not limited to, the HTTP request, the connection timers, the session
8893 status, the connections numbers, the captured headers and cookies, the
8894 frontend, backend and server name, and of course the source address and
8895 ports.
8896
PiBa-NLbd556bf2014-12-11 21:31:54 +01008897 Specifying only "option httplog" will automatically clear the 'clf' mode
8898 if it was set by default.
Emeric Brun3a058f32009-06-30 18:26:00 +02008899
Guillaume de Lafond29f45602017-03-31 19:52:15 +02008900 "option httplog" overrides any previous "log-format" directive.
8901
Willy Tarreauc57f0e22009-05-10 13:12:33 +02008902 See also : section 8 about logging.
Willy Tarreauc27debf2008-01-06 08:57:02 +01008903
Willy Tarreau55165fe2009-05-10 12:02:55 +02008904
8905option http_proxy
8906no option http_proxy
8907 Enable or disable plain HTTP proxy mode
8908 May be used in sections : defaults | frontend | listen | backend
8909 yes | yes | yes | yes
8910 Arguments : none
8911
8912 It sometimes happens that people need a pure HTTP proxy which understands
8913 basic proxy requests without caching nor any fancy feature. In this case,
8914 it may be worth setting up an HAProxy instance with the "option http_proxy"
8915 set. In this mode, no server is declared, and the connection is forwarded to
8916 the IP address and port found in the URL after the "http://" scheme.
8917
8918 No host address resolution is performed, so this only works when pure IP
8919 addresses are passed. Since this option's usage perimeter is rather limited,
Lukas Tribusf01a9cd2016-02-03 18:09:37 +01008920 it will probably be used only by experts who know they need exactly it. This
8921 is incompatible with the HTTP tunnel mode.
Willy Tarreau55165fe2009-05-10 12:02:55 +02008922
8923 If this option has been enabled in a "defaults" section, it can be disabled
8924 in a specific instance by prepending the "no" keyword before it.
8925
8926 Example :
8927 # this backend understands HTTP proxy requests and forwards them directly.
8928 backend direct_forward
8929 option httpclose
8930 option http_proxy
8931
8932 See also : "option httpclose"
8933
Willy Tarreau211ad242009-10-03 21:45:07 +02008934
Jamie Gloudon801a0a32012-08-25 00:18:33 -04008935option independent-streams
8936no option independent-streams
8937 Enable or disable independent timeout processing for both directions
Willy Tarreauf27b5ea2009-10-03 22:01:18 +02008938 May be used in sections : defaults | frontend | listen | backend
8939 yes | yes | yes | yes
8940 Arguments : none
8941
8942 By default, when data is sent over a socket, both the write timeout and the
8943 read timeout for that socket are refreshed, because we consider that there is
8944 activity on that socket, and we have no other means of guessing if we should
8945 receive data or not.
8946
Davor Ocelice9ed2812017-12-25 17:49:28 +01008947 While this default behavior is desirable for almost all applications, there
Willy Tarreauf27b5ea2009-10-03 22:01:18 +02008948 exists a situation where it is desirable to disable it, and only refresh the
8949 read timeout if there are incoming data. This happens on sessions with large
8950 timeouts and low amounts of exchanged data such as telnet session. If the
8951 server suddenly disappears, the output data accumulates in the system's
8952 socket buffers, both timeouts are correctly refreshed, and there is no way
8953 to know the server does not receive them, so we don't timeout. However, when
8954 the underlying protocol always echoes sent data, it would be enough by itself
8955 to detect the issue using the read timeout. Note that this problem does not
8956 happen with more verbose protocols because data won't accumulate long in the
8957 socket buffers.
8958
8959 When this option is set on the frontend, it will disable read timeout updates
8960 on data sent to the client. There probably is little use of this case. When
8961 the option is set on the backend, it will disable read timeout updates on
8962 data sent to the server. Doing so will typically break large HTTP posts from
8963 slow lines, so use it with caution.
8964
Willy Tarreauce887fd2012-05-12 12:50:00 +02008965 See also : "timeout client", "timeout server" and "timeout tunnel"
Willy Tarreauf27b5ea2009-10-03 22:01:18 +02008966
8967
Gabor Lekenyb4c81e42010-09-29 18:17:05 +02008968option ldap-check
8969 Use LDAPv3 health checks for server testing
8970 May be used in sections : defaults | frontend | listen | backend
8971 yes | no | yes | yes
8972 Arguments : none
8973
8974 It is possible to test that the server correctly talks LDAPv3 instead of just
8975 testing that it accepts the TCP connection. When this option is set, an
8976 LDAPv3 anonymous simple bind message is sent to the server, and the response
8977 is analyzed to find an LDAPv3 bind response message.
8978
8979 The server is considered valid only when the LDAP response contains success
8980 resultCode (http://tools.ietf.org/html/rfc4511#section-4.1.9).
8981
8982 Logging of bind requests is server dependent see your documentation how to
8983 configure it.
8984
8985 Example :
8986 option ldap-check
8987
8988 See also : "option httpchk"
8989
8990
Simon Horman98637e52014-06-20 12:30:16 +09008991option external-check
8992 Use external processes for server health checks
8993 May be used in sections : defaults | frontend | listen | backend
8994 yes | no | yes | yes
8995
8996 It is possible to test the health of a server using an external command.
8997 This is achieved by running the executable set using "external-check
8998 command".
8999
9000 Requires the "external-check" global to be set.
9001
9002 See also : "external-check", "external-check command", "external-check path"
9003
9004
Willy Tarreau211ad242009-10-03 21:45:07 +02009005option log-health-checks
9006no option log-health-checks
Willy Tarreaubef1b322014-05-13 21:01:39 +02009007 Enable or disable logging of health checks status updates
Willy Tarreau211ad242009-10-03 21:45:07 +02009008 May be used in sections : defaults | frontend | listen | backend
9009 yes | no | yes | yes
9010 Arguments : none
9011
Willy Tarreaubef1b322014-05-13 21:01:39 +02009012 By default, failed health check are logged if server is UP and successful
9013 health checks are logged if server is DOWN, so the amount of additional
9014 information is limited.
Willy Tarreau211ad242009-10-03 21:45:07 +02009015
Willy Tarreaubef1b322014-05-13 21:01:39 +02009016 When this option is enabled, any change of the health check status or to
9017 the server's health will be logged, so that it becomes possible to know
9018 that a server was failing occasional checks before crashing, or exactly when
9019 it failed to respond a valid HTTP status, then when the port started to
9020 reject connections, then when the server stopped responding at all.
9021
Davor Ocelice9ed2812017-12-25 17:49:28 +01009022 Note that status changes not caused by health checks (e.g. enable/disable on
Willy Tarreaubef1b322014-05-13 21:01:39 +02009023 the CLI) are intentionally not logged by this option.
Willy Tarreau211ad242009-10-03 21:45:07 +02009024
Willy Tarreaubef1b322014-05-13 21:01:39 +02009025 See also: "option httpchk", "option ldap-check", "option mysql-check",
9026 "option pgsql-check", "option redis-check", "option smtpchk",
9027 "option tcp-check", "log" and section 8 about logging.
Willy Tarreau211ad242009-10-03 21:45:07 +02009028
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +02009029
9030option log-separate-errors
9031no option log-separate-errors
9032 Change log level for non-completely successful connections
9033 May be used in sections : defaults | frontend | listen | backend
9034 yes | yes | yes | no
9035 Arguments : none
9036
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009037 Sometimes looking for errors in logs is not easy. This option makes HAProxy
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +02009038 raise the level of logs containing potentially interesting information such
9039 as errors, timeouts, retries, redispatches, or HTTP status codes 5xx. The
9040 level changes from "info" to "err". This makes it possible to log them
9041 separately to a different file with most syslog daemons. Be careful not to
9042 remove them from the original file, otherwise you would lose ordering which
9043 provides very important information.
9044
9045 Using this option, large sites dealing with several thousand connections per
9046 second may log normal traffic to a rotating buffer and only archive smaller
9047 error logs.
9048
Willy Tarreauc57f0e22009-05-10 13:12:33 +02009049 See also : "log", "dontlognull", "dontlog-normal" and section 8 about
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +02009050 logging.
9051
Willy Tarreauc27debf2008-01-06 08:57:02 +01009052
9053option logasap
9054no option logasap
Jerome Magnin95fb57b2020-04-23 19:01:17 +02009055 Enable or disable early logging.
Willy Tarreauc27debf2008-01-06 08:57:02 +01009056 May be used in sections : defaults | frontend | listen | backend
9057 yes | yes | yes | no
9058 Arguments : none
9059
Jerome Magnin95fb57b2020-04-23 19:01:17 +02009060 By default, logs are emitted when all the log format variables and sample
9061 fetches used in the definition of the log-format string return a value, or
9062 when the session is terminated. This allows the built in log-format strings
9063 to account for the transfer time, or the number of bytes in log messages.
9064
9065 When handling long lived connections such as large file transfers or RDP,
9066 it may take a while for the request or connection to appear in the logs.
9067 Using "option logasap", the log message is created as soon as the server
9068 connection is established in mode tcp, or as soon as the server sends the
9069 complete headers in mode http. Missing information in the logs will be the
Ilya Shipitsin4329a9a2020-05-05 21:17:10 +05009070 total number of bytes which will only indicate the amount of data transferred
Jerome Magnin95fb57b2020-04-23 19:01:17 +02009071 before the message was created and the total time which will not take the
9072 remainder of the connection life or transfer time into account. For the case
9073 of HTTP, it is good practice to capture the Content-Length response header
9074 so that the logs at least indicate how many bytes are expected to be
Ilya Shipitsin4329a9a2020-05-05 21:17:10 +05009075 transferred.
Willy Tarreauc27debf2008-01-06 08:57:02 +01009076
Willy Tarreaucc6c8912009-02-22 10:53:55 +01009077 Examples :
9078 listen http_proxy 0.0.0.0:80
9079 mode http
9080 option httplog
9081 option logasap
9082 log 192.168.2.200 local3
9083
9084 >>> Feb 6 12:14:14 localhost \
9085 haproxy[14389]: 10.0.1.2:33317 [06/Feb/2009:12:14:14.655] http-in \
9086 static/srv1 9/10/7/14/+30 200 +243 - - ---- 3/1/1/1/0 1/0 \
9087 "GET /image.iso HTTP/1.0"
9088
Willy Tarreauc57f0e22009-05-10 13:12:33 +02009089 See also : "option httplog", "capture response header", and section 8 about
Willy Tarreauc27debf2008-01-06 08:57:02 +01009090 logging.
9091
9092
Christopher Faulet62f79fe2020-05-18 18:13:03 +02009093option mysql-check [ user <username> [ { post-41 | pre-41 } ] ]
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009094 Use MySQL health checks for server testing
Hervé COMMOWICK698ae002010-01-12 09:25:13 +01009095 May be used in sections : defaults | frontend | listen | backend
9096 yes | no | yes | yes
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009097 Arguments :
Cyril Bonté108cf6e2012-04-21 23:30:29 +02009098 <username> This is the username which will be used when connecting to MySQL
9099 server.
Christopher Faulet62f79fe2020-05-18 18:13:03 +02009100 post-41 Send post v4.1 client compatible checks (the default)
9101 pre-41 Send pre v4.1 client compatible checks
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009102
9103 If you specify a username, the check consists of sending two MySQL packet,
9104 one Client Authentication packet, and one QUIT packet, to correctly close
Davor Ocelice9ed2812017-12-25 17:49:28 +01009105 MySQL session. We then parse the MySQL Handshake Initialization packet and/or
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009106 Error packet. It is a basic but useful test which does not produce error nor
Daniel Black9dc310d2021-07-01 12:09:32 +10009107 aborted connect on the server. However, it requires an unlocked authorised
9108 user without a password. To create a basic limited user in MySQL with
9109 optional resource limits:
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009110
Daniel Black9dc310d2021-07-01 12:09:32 +10009111 CREATE USER '<username>'@'<ip_of_haproxy|network_of_haproxy/netmask>'
9112 /*!50701 WITH MAX_QUERIES_PER_HOUR 1 MAX_UPDATES_PER_HOUR 0 */
9113 /*M!100201 MAX_STATEMENT_TIME 0.0001 */;
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009114
9115 If you don't specify a username (it is deprecated and not recommended), the
Davor Ocelice9ed2812017-12-25 17:49:28 +01009116 check only consists in parsing the Mysql Handshake Initialization packet or
Hervé COMMOWICK8776f1b2010-10-18 15:58:36 +02009117 Error packet, we don't send anything in this mode. It was reported that it
9118 can generate lockout if check is too frequent and/or if there is not enough
9119 traffic. In fact, you need in this case to check MySQL "max_connect_errors"
9120 value as if a connection is established successfully within fewer than MySQL
9121 "max_connect_errors" attempts after a previous connection was interrupted,
9122 the error count for the host is cleared to zero. If HAProxy's server get
9123 blocked, the "FLUSH HOSTS" statement is the only way to unblock it.
9124
9125 Remember that this does not check database presence nor database consistency.
9126 To do this, you can use an external check with xinetd for example.
Hervé COMMOWICK698ae002010-01-12 09:25:13 +01009127
Hervé COMMOWICK212f7782011-06-10 14:05:59 +02009128 The check requires MySQL >=3.22, for older version, please use TCP check.
Hervé COMMOWICK698ae002010-01-12 09:25:13 +01009129
9130 Most often, an incoming MySQL server needs to see the client's IP address for
9131 various purposes, including IP privilege matching and connection logging.
9132 When possible, it is often wise to masquerade the client's IP address when
9133 connecting to the server using the "usesrc" argument of the "source" keyword,
Willy Tarreau29fbe512015-08-20 19:35:14 +02009134 which requires the transparent proxy feature to be compiled in, and the MySQL
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009135 server to route the client via the machine hosting HAProxy.
Hervé COMMOWICK698ae002010-01-12 09:25:13 +01009136
9137 See also: "option httpchk"
9138
9139
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009140option nolinger
9141no option nolinger
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01009142 Enable or disable immediate session resource cleaning after close
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009143 May be used in sections: defaults | frontend | listen | backend
9144 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +01009145 Arguments : none
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009146
Davor Ocelice9ed2812017-12-25 17:49:28 +01009147 When clients or servers abort connections in a dirty way (e.g. they are
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009148 physically disconnected), the session timeouts triggers and the session is
9149 closed. But it will remain in FIN_WAIT1 state for some time in the system,
9150 using some resources and possibly limiting the ability to establish newer
9151 connections.
9152
9153 When this happens, it is possible to activate "option nolinger" which forces
9154 the system to immediately remove any socket's pending data on close. Thus,
Willy Tarreau4a321032020-10-16 04:55:19 +02009155 a TCP RST is emitted, any pending data are truncated, and the session is
9156 instantly purged from the system's tables. The generally visible effect for
9157 a client is that responses are truncated if the close happens with a last
9158 block of data (e.g. on a redirect or error response). On the server side,
9159 it may help release the source ports immediately when forwarding a client
9160 aborts in tunnels. In both cases, TCP resets are emitted and given that
9161 the session is instantly destroyed, there will be no retransmit. On a lossy
9162 network this can increase problems, especially when there is a firewall on
9163 the lossy side, because the firewall might see and process the reset (hence
9164 purge its session) and block any further traffic for this session,, including
9165 retransmits from the other side. So if the other side doesn't receive it,
9166 it will never receive any RST again, and the firewall might log many blocked
9167 packets.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009168
Willy Tarreau4a321032020-10-16 04:55:19 +02009169 For all these reasons, it is strongly recommended NOT to use this option,
9170 unless absolutely needed as a last resort. In most situations, using the
9171 "client-fin" or "server-fin" timeouts achieves similar results with a more
9172 reliable behavior. On Linux it's also possible to use the "tcp-ut" bind or
9173 server setting.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009174
9175 This option may be used both on frontends and backends, depending on the side
9176 where it is required. Use it on the frontend for clients, and on the backend
Willy Tarreau4a321032020-10-16 04:55:19 +02009177 for servers. While this option is technically supported in "defaults"
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +05009178 sections, it must really not be used there as it risks to accidentally
Willy Tarreau4a321032020-10-16 04:55:19 +02009179 propagate to sections that must no use it and to cause problems there.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009180
9181 If this option has been enabled in a "defaults" section, it can be disabled
9182 in a specific instance by prepending the "no" keyword before it.
9183
Willy Tarreau4a321032020-10-16 04:55:19 +02009184 See also: "timeout client-fin", "timeout server-fin", "tcp-ut" bind or server
9185 keywords.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009186
Willy Tarreau55165fe2009-05-10 12:02:55 +02009187option originalto [ except <network> ] [ header <name> ]
9188 Enable insertion of the X-Original-To header to requests sent to servers
9189 May be used in sections : defaults | frontend | listen | backend
9190 yes | yes | yes | yes
9191 Arguments :
9192 <network> is an optional argument used to disable this option for sources
9193 matching <network>
9194 <name> an optional argument to specify a different "X-Original-To"
9195 header name.
9196
9197 Since HAProxy can work in transparent mode, every request from a client can
9198 be redirected to the proxy and HAProxy itself can proxy every request to a
9199 complex SQUID environment and the destination host from SO_ORIGINAL_DST will
9200 be lost. This is annoying when you want access rules based on destination ip
9201 addresses. To solve this problem, a new HTTP header "X-Original-To" may be
9202 added by HAProxy to all requests sent to the server. This header contains a
9203 value representing the original destination IP address. Since this must be
9204 configured to always use the last occurrence of this header only. Note that
9205 only the last occurrence of the header must be used, since it is really
9206 possible that the client has already brought one.
9207
9208 The keyword "header" may be used to supply a different header name to replace
9209 the default "X-Original-To". This can be useful where you might already
9210 have a "X-Original-To" header from a different application, and you need
9211 preserve it. Also if your backend server doesn't use the "X-Original-To"
9212 header and requires different one.
9213
9214 Sometimes, a same HAProxy instance may be shared between a direct client
9215 access and a reverse-proxy access (for instance when an SSL reverse-proxy is
9216 used to decrypt HTTPS traffic). It is possible to disable the addition of the
Amaury Denoyellef8b42922021-03-04 18:41:14 +01009217 header for a known destination address or network by adding the "except"
9218 keyword followed by the network address. In this case, any destination IP
9219 matching the network will not cause an addition of this header. Most common
9220 uses are with private networks or 127.0.0.1. IPv4 and IPv6 are both
9221 supported.
Willy Tarreau55165fe2009-05-10 12:02:55 +02009222
9223 This option may be specified either in the frontend or in the backend. If at
9224 least one of them uses it, the header will be added. Note that the backend's
9225 setting of the header subargument takes precedence over the frontend's if
9226 both are defined.
9227
Willy Tarreau55165fe2009-05-10 12:02:55 +02009228 Examples :
9229 # Original Destination address
9230 frontend www
9231 mode http
9232 option originalto except 127.0.0.1
9233
9234 # Those servers want the IP Address in X-Client-Dst
9235 backend www
9236 mode http
9237 option originalto header X-Client-Dst
9238
Christopher Faulet315b39c2018-09-21 16:26:19 +02009239 See also : "option httpclose", "option http-server-close".
Willy Tarreau55165fe2009-05-10 12:02:55 +02009240
9241
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009242option persist
9243no option persist
9244 Enable or disable forced persistence on down servers
9245 May be used in sections: defaults | frontend | listen | backend
9246 yes | no | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +01009247 Arguments : none
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009248
9249 When an HTTP request reaches a backend with a cookie which references a dead
9250 server, by default it is redispatched to another server. It is possible to
9251 force the request to be sent to the dead server first using "option persist"
9252 if absolutely needed. A common use case is when servers are under extreme
9253 load and spend their time flapping. In this case, the users would still be
9254 directed to the server they opened the session on, in the hope they would be
9255 correctly served. It is recommended to use "option redispatch" in conjunction
9256 with this option so that in the event it would not be possible to connect to
9257 the server at all (server definitely dead), the client would finally be
9258 redirected to another valid server.
9259
9260 If this option has been enabled in a "defaults" section, it can be disabled
9261 in a specific instance by prepending the "no" keyword before it.
9262
Willy Tarreau4de91492010-01-22 19:10:05 +01009263 See also : "option redispatch", "retries", "force-persist"
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009264
9265
Willy Tarreau0c122822013-12-15 18:49:01 +01009266option pgsql-check [ user <username> ]
9267 Use PostgreSQL health checks for server testing
9268 May be used in sections : defaults | frontend | listen | backend
9269 yes | no | yes | yes
9270 Arguments :
9271 <username> This is the username which will be used when connecting to
9272 PostgreSQL server.
9273
9274 The check sends a PostgreSQL StartupMessage and waits for either
9275 Authentication request or ErrorResponse message. It is a basic but useful
9276 test which does not produce error nor aborted connect on the server.
9277 This check is identical with the "mysql-check".
9278
9279 See also: "option httpchk"
9280
9281
Willy Tarreau9420b122013-12-15 18:58:25 +01009282option prefer-last-server
9283no option prefer-last-server
9284 Allow multiple load balanced requests to remain on the same server
9285 May be used in sections: defaults | frontend | listen | backend
9286 yes | no | yes | yes
9287 Arguments : none
9288
9289 When the load balancing algorithm in use is not deterministic, and a previous
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009290 request was sent to a server to which HAProxy still holds a connection, it is
Willy Tarreau9420b122013-12-15 18:58:25 +01009291 sometimes desirable that subsequent requests on a same session go to the same
9292 server as much as possible. Note that this is different from persistence, as
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009293 we only indicate a preference which HAProxy tries to apply without any form
Willy Tarreau9420b122013-12-15 18:58:25 +01009294 of warranty. The real use is for keep-alive connections sent to servers. When
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009295 this option is used, HAProxy will try to reuse the same connection that is
Willy Tarreau9420b122013-12-15 18:58:25 +01009296 attached to the server instead of rebalancing to another server, causing a
9297 close of the connection. This can make sense for static file servers. It does
Willy Tarreau068621e2013-12-23 15:11:25 +01009298 not make much sense to use this in combination with hashing algorithms. Note,
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009299 HAProxy already automatically tries to stick to a server which sends a 401 or
Lukas Tribus80512b12018-10-27 20:07:40 +02009300 to a proxy which sends a 407 (authentication required), when the load
9301 balancing algorithm is not deterministic. This is mandatory for use with the
9302 broken NTLM authentication challenge, and significantly helps in
Willy Tarreau068621e2013-12-23 15:11:25 +01009303 troubleshooting some faulty applications. Option prefer-last-server might be
9304 desirable in these environments as well, to avoid redistributing the traffic
9305 after every other response.
Willy Tarreau9420b122013-12-15 18:58:25 +01009306
9307 If this option has been enabled in a "defaults" section, it can be disabled
9308 in a specific instance by prepending the "no" keyword before it.
9309
9310 See also: "option http-keep-alive"
9311
9312
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009313option redispatch
Joseph Lynch726ab712015-05-11 23:25:34 -07009314option redispatch <interval>
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009315no option redispatch
9316 Enable or disable session redistribution in case of connection failure
9317 May be used in sections: defaults | frontend | listen | backend
9318 yes | no | yes | yes
Joseph Lynch726ab712015-05-11 23:25:34 -07009319 Arguments :
9320 <interval> The optional integer value that controls how often redispatches
9321 occur when retrying connections. Positive value P indicates a
9322 redispatch is desired on every Pth retry, and negative value
Davor Ocelice9ed2812017-12-25 17:49:28 +01009323 N indicate a redispatch is desired on the Nth retry prior to the
Joseph Lynch726ab712015-05-11 23:25:34 -07009324 last retry. For example, the default of -1 preserves the
Davor Ocelice9ed2812017-12-25 17:49:28 +01009325 historical behavior of redispatching on the last retry, a
Joseph Lynch726ab712015-05-11 23:25:34 -07009326 positive value of 1 would indicate a redispatch on every retry,
9327 and a positive value of 3 would indicate a redispatch on every
9328 third retry. You can disable redispatches with a value of 0.
9329
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009330
9331 In HTTP mode, if a server designated by a cookie is down, clients may
9332 definitely stick to it because they cannot flush the cookie, so they will not
9333 be able to access the service anymore.
9334
Willy Tarreau59884a62019-01-02 14:48:31 +01009335 Specifying "option redispatch" will allow the proxy to break cookie or
9336 consistent hash based persistence and redistribute them to a working server.
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009337
Olivier Carrère6e6f59b2020-04-15 11:30:18 +02009338 Active servers are selected from a subset of the list of available
9339 servers. Active servers that are not down or in maintenance (i.e., whose
9340 health is not checked or that have been checked as "up"), are selected in the
9341 following order:
9342
9343 1. Any active, non-backup server, if any, or,
9344
9345 2. If the "allbackups" option is not set, the first backup server in the
9346 list, or
9347
9348 3. If the "allbackups" option is set, any backup server.
9349
9350 When a retry occurs, HAProxy tries to select another server than the last
9351 one. The new server is selected from the current list of servers.
9352
9353 Sometimes, if the list is updated between retries (e.g., if numerous retries
9354 occur and last longer than the time needed to check that a server is down,
9355 remove it from the list and fall back on the list of backup servers),
9356 connections may be redirected to a backup server, though.
9357
Joseph Lynch726ab712015-05-11 23:25:34 -07009358 It also allows to retry connections to another server in case of multiple
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009359 connection failures. Of course, it requires having "retries" set to a nonzero
9360 value.
Willy Tarreaud72758d2010-01-12 10:42:19 +01009361
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009362 If this option has been enabled in a "defaults" section, it can be disabled
9363 in a specific instance by prepending the "no" keyword before it.
9364
Christopher Faulet87f1f3d2019-07-18 14:51:20 +02009365 See also : "retries", "force-persist"
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009366
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009367
Hervé COMMOWICKec032d62011-08-05 16:23:48 +02009368option redis-check
9369 Use redis health checks for server testing
9370 May be used in sections : defaults | frontend | listen | backend
9371 yes | no | yes | yes
9372 Arguments : none
9373
9374 It is possible to test that the server correctly talks REDIS protocol instead
9375 of just testing that it accepts the TCP connection. When this option is set,
9376 a PING redis command is sent to the server, and the response is analyzed to
9377 find the "+PONG" response message.
9378
9379 Example :
9380 option redis-check
9381
Jarno Huuskonene5ae7022017-04-03 14:36:21 +03009382 See also : "option httpchk", "option tcp-check", "tcp-check expect"
Hervé COMMOWICKec032d62011-08-05 16:23:48 +02009383
9384
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009385option smtpchk
9386option smtpchk <hello> <domain>
9387 Use SMTP health checks for server testing
9388 May be used in sections : defaults | frontend | listen | backend
9389 yes | no | yes | yes
Willy Tarreaud72758d2010-01-12 10:42:19 +01009390 Arguments :
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009391 <hello> is an optional argument. It is the "hello" command to use. It can
Lukas Tribus27935782018-10-01 02:00:16 +02009392 be either "HELO" (for SMTP) or "EHLO" (for ESMTP). All other
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009393 values will be turned into the default command ("HELO").
9394
9395 <domain> is the domain name to present to the server. It may only be
9396 specified (and is mandatory) if the hello command has been
9397 specified. By default, "localhost" is used.
9398
9399 When "option smtpchk" is set, the health checks will consist in TCP
9400 connections followed by an SMTP command. By default, this command is
9401 "HELO localhost". The server's return code is analyzed and only return codes
9402 starting with a "2" will be considered as valid. All other responses,
9403 including a lack of response will constitute an error and will indicate a
9404 dead server.
9405
9406 This test is meant to be used with SMTP servers or relays. Depending on the
9407 request, it is possible that some servers do not log each connection attempt,
Davor Ocelice9ed2812017-12-25 17:49:28 +01009408 so you may want to experiment to improve the behavior. Using telnet on port
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009409 25 is often easier than adjusting the configuration.
9410
9411 Most often, an incoming SMTP server needs to see the client's IP address for
9412 various purposes, including spam filtering, anti-spoofing and logging. When
9413 possible, it is often wise to masquerade the client's IP address when
9414 connecting to the server using the "usesrc" argument of the "source" keyword,
Willy Tarreau29fbe512015-08-20 19:35:14 +02009415 which requires the transparent proxy feature to be compiled in.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009416
9417 Example :
9418 option smtpchk HELO mydomain.org
9419
9420 See also : "option httpchk", "source"
9421
Krzysztof Piotr Oledzki25b501a2008-01-06 16:36:16 +01009422
Krzysztof Piotr Oledzkiaeebf9b2009-10-04 15:43:17 +02009423option socket-stats
9424no option socket-stats
9425
9426 Enable or disable collecting & providing separate statistics for each socket.
9427 May be used in sections : defaults | frontend | listen | backend
9428 yes | yes | yes | no
9429
9430 Arguments : none
9431
9432
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009433option splice-auto
9434no option splice-auto
9435 Enable or disable automatic kernel acceleration on sockets in both directions
9436 May be used in sections : defaults | frontend | listen | backend
9437 yes | yes | yes | yes
9438 Arguments : none
9439
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009440 When this option is enabled either on a frontend or on a backend, HAProxy
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009441 will automatically evaluate the opportunity to use kernel tcp splicing to
Davor Ocelice9ed2812017-12-25 17:49:28 +01009442 forward data between the client and the server, in either direction. HAProxy
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009443 uses heuristics to estimate if kernel splicing might improve performance or
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01009444 not. Both directions are handled independently. Note that the heuristics used
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009445 are not much aggressive in order to limit excessive use of splicing. This
9446 option requires splicing to be enabled at compile time, and may be globally
9447 disabled with the global option "nosplice". Since splice uses pipes, using it
9448 requires that there are enough spare pipes.
9449
9450 Important note: kernel-based TCP splicing is a Linux-specific feature which
9451 first appeared in kernel 2.6.25. It offers kernel-based acceleration to
9452 transfer data between sockets without copying these data to user-space, thus
9453 providing noticeable performance gains and CPU cycles savings. Since many
9454 early implementations are buggy, corrupt data and/or are inefficient, this
9455 feature is not enabled by default, and it should be used with extreme care.
9456 While it is not possible to detect the correctness of an implementation,
9457 2.6.29 is the first version offering a properly working implementation. In
9458 case of doubt, splicing may be globally disabled using the global "nosplice"
9459 keyword.
9460
9461 Example :
9462 option splice-auto
9463
9464 If this option has been enabled in a "defaults" section, it can be disabled
9465 in a specific instance by prepending the "no" keyword before it.
9466
9467 See also : "option splice-request", "option splice-response", and global
9468 options "nosplice" and "maxpipes"
9469
9470
9471option splice-request
9472no option splice-request
9473 Enable or disable automatic kernel acceleration on sockets for requests
9474 May be used in sections : defaults | frontend | listen | backend
9475 yes | yes | yes | yes
9476 Arguments : none
9477
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009478 When this option is enabled either on a frontend or on a backend, HAProxy
Jamie Gloudonaaa21002012-08-25 00:18:33 -04009479 will use kernel tcp splicing whenever possible to forward data going from
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009480 the client to the server. It might still use the recv/send scheme if there
9481 are no spare pipes left. This option requires splicing to be enabled at
9482 compile time, and may be globally disabled with the global option "nosplice".
9483 Since splice uses pipes, using it requires that there are enough spare pipes.
9484
9485 Important note: see "option splice-auto" for usage limitations.
9486
9487 Example :
9488 option splice-request
9489
9490 If this option has been enabled in a "defaults" section, it can be disabled
9491 in a specific instance by prepending the "no" keyword before it.
9492
9493 See also : "option splice-auto", "option splice-response", and global options
9494 "nosplice" and "maxpipes"
9495
9496
9497option splice-response
9498no option splice-response
9499 Enable or disable automatic kernel acceleration on sockets for responses
9500 May be used in sections : defaults | frontend | listen | backend
9501 yes | yes | yes | yes
9502 Arguments : none
9503
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009504 When this option is enabled either on a frontend or on a backend, HAProxy
Jamie Gloudonaaa21002012-08-25 00:18:33 -04009505 will use kernel tcp splicing whenever possible to forward data going from
Willy Tarreauff4f82d2009-02-06 11:28:13 +01009506 the server to the client. It might still use the recv/send scheme if there
9507 are no spare pipes left. This option requires splicing to be enabled at
9508 compile time, and may be globally disabled with the global option "nosplice".
9509 Since splice uses pipes, using it requires that there are enough spare pipes.
9510
9511 Important note: see "option splice-auto" for usage limitations.
9512
9513 Example :
9514 option splice-response
9515
9516 If this option has been enabled in a "defaults" section, it can be disabled
9517 in a specific instance by prepending the "no" keyword before it.
9518
9519 See also : "option splice-auto", "option splice-request", and global options
9520 "nosplice" and "maxpipes"
9521
9522
Christopher Fauletba7bc162016-11-07 21:07:38 +01009523option spop-check
9524 Use SPOP health checks for server testing
9525 May be used in sections : defaults | frontend | listen | backend
9526 no | no | no | yes
9527 Arguments : none
9528
9529 It is possible to test that the server correctly talks SPOP protocol instead
9530 of just testing that it accepts the TCP connection. When this option is set,
9531 a HELLO handshake is performed between HAProxy and the server, and the
9532 response is analyzed to check no error is reported.
9533
9534 Example :
9535 option spop-check
9536
9537 See also : "option httpchk"
9538
9539
Willy Tarreaubf1f8162007-12-28 17:42:56 +01009540option srvtcpka
9541no option srvtcpka
9542 Enable or disable the sending of TCP keepalive packets on the server side
9543 May be used in sections : defaults | frontend | listen | backend
9544 yes | no | yes | yes
9545 Arguments : none
9546
9547 When there is a firewall or any session-aware component between a client and
9548 a server, and when the protocol involves very long sessions with long idle
Davor Ocelice9ed2812017-12-25 17:49:28 +01009549 periods (e.g. remote desktops), there is a risk that one of the intermediate
Willy Tarreaubf1f8162007-12-28 17:42:56 +01009550 components decides to expire a session which has remained idle for too long.
9551
9552 Enabling socket-level TCP keep-alives makes the system regularly send packets
9553 to the other end of the connection, leaving it active. The delay between
9554 keep-alive probes is controlled by the system only and depends both on the
9555 operating system and its tuning parameters.
9556
9557 It is important to understand that keep-alive packets are neither emitted nor
9558 received at the application level. It is only the network stacks which sees
9559 them. For this reason, even if one side of the proxy already uses keep-alives
9560 to maintain its connection alive, those keep-alive packets will not be
9561 forwarded to the other side of the proxy.
9562
9563 Please note that this has nothing to do with HTTP keep-alive.
9564
9565 Using option "srvtcpka" enables the emission of TCP keep-alive probes on the
9566 server side of a connection, which should help when session expirations are
9567 noticed between HAProxy and a server.
9568
9569 If this option has been enabled in a "defaults" section, it can be disabled
9570 in a specific instance by prepending the "no" keyword before it.
9571
9572 See also : "option clitcpka", "option tcpka"
9573
9574
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009575option ssl-hello-chk
9576 Use SSLv3 client hello health checks for server testing
9577 May be used in sections : defaults | frontend | listen | backend
9578 yes | no | yes | yes
9579 Arguments : none
9580
9581 When some SSL-based protocols are relayed in TCP mode through HAProxy, it is
9582 possible to test that the server correctly talks SSL instead of just testing
9583 that it accepts the TCP connection. When "option ssl-hello-chk" is set, pure
9584 SSLv3 client hello messages are sent once the connection is established to
9585 the server, and the response is analyzed to find an SSL server hello message.
9586 The server is considered valid only when the response contains this server
9587 hello message.
9588
9589 All servers tested till there correctly reply to SSLv3 client hello messages,
9590 and most servers tested do not even log the requests containing only hello
9591 messages, which is appreciable.
9592
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009593 Note that this check works even when SSL support was not built into HAProxy
Willy Tarreau763a95b2012-10-04 23:15:39 +02009594 because it forges the SSL message. When SSL support is available, it is best
9595 to use native SSL health checks instead of this one.
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009596
Willy Tarreau763a95b2012-10-04 23:15:39 +02009597 See also: "option httpchk", "check-ssl"
9598
Willy Tarreaua453bdd2008-01-08 19:50:52 +01009599
Willy Tarreaued179852013-12-16 01:07:00 +01009600option tcp-check
9601 Perform health checks using tcp-check send/expect sequences
9602 May be used in sections: defaults | frontend | listen | backend
9603 yes | no | yes | yes
9604
9605 This health check method is intended to be combined with "tcp-check" command
9606 lists in order to support send/expect types of health check sequences.
9607
9608 TCP checks currently support 4 modes of operations :
9609 - no "tcp-check" directive : the health check only consists in a connection
9610 attempt, which remains the default mode.
9611
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03009612 - "tcp-check send" or "tcp-check send-binary" only is mentioned : this is
Willy Tarreaued179852013-12-16 01:07:00 +01009613 used to send a string along with a connection opening. With some
9614 protocols, it helps sending a "QUIT" message for example that prevents
9615 the server from logging a connection error for each health check. The
9616 check result will still be based on the ability to open the connection
9617 only.
9618
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03009619 - "tcp-check expect" only is mentioned : this is used to test a banner.
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009620 The connection is opened and HAProxy waits for the server to present some
Willy Tarreaued179852013-12-16 01:07:00 +01009621 contents which must validate some rules. The check result will be based
9622 on the matching between the contents and the rules. This is suited for
9623 POP, IMAP, SMTP, FTP, SSH, TELNET.
9624
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03009625 - both "tcp-check send" and "tcp-check expect" are mentioned : this is
Davor Ocelice9ed2812017-12-25 17:49:28 +01009626 used to test a hello-type protocol. HAProxy sends a message, the server
9627 responds and its response is analyzed. the check result will be based on
Jarno Huuskonen0e82b922014-04-12 18:22:19 +03009628 the matching between the response contents and the rules. This is often
Willy Tarreaued179852013-12-16 01:07:00 +01009629 suited for protocols which require a binding or a request/response model.
9630 LDAP, MySQL, Redis and SSL are example of such protocols, though they
9631 already all have their dedicated checks with a deeper understanding of
9632 the respective protocols.
9633 In this mode, many questions may be sent and many answers may be
Davor Ocelice9ed2812017-12-25 17:49:28 +01009634 analyzed.
Willy Tarreaued179852013-12-16 01:07:00 +01009635
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02009636 A fifth mode can be used to insert comments in different steps of the script.
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009637
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02009638 For each tcp-check rule you create, you can add a "comment" directive,
9639 followed by a string. This string will be reported in the log and stderr in
9640 debug mode. It is useful to make user-friendly error reporting. The
9641 "comment" is of course optional.
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009642
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02009643 During the execution of a health check, a variable scope is made available to
9644 store data samples, using the "tcp-check set-var" operation. Freeing those
9645 variable is possible using "tcp-check unset-var".
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +01009646
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009647
Willy Tarreaued179852013-12-16 01:07:00 +01009648 Examples :
Davor Ocelice9ed2812017-12-25 17:49:28 +01009649 # perform a POP check (analyze only server's banner)
Willy Tarreaued179852013-12-16 01:07:00 +01009650 option tcp-check
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009651 tcp-check expect string +OK\ POP3\ ready comment POP\ protocol
Willy Tarreaued179852013-12-16 01:07:00 +01009652
Davor Ocelice9ed2812017-12-25 17:49:28 +01009653 # perform an IMAP check (analyze only server's banner)
Willy Tarreaued179852013-12-16 01:07:00 +01009654 option tcp-check
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009655 tcp-check expect string *\ OK\ IMAP4\ ready comment IMAP\ protocol
Willy Tarreaued179852013-12-16 01:07:00 +01009656
9657 # look for the redis master server after ensuring it speaks well
9658 # redis protocol, then it exits properly.
Davor Ocelice9ed2812017-12-25 17:49:28 +01009659 # (send a command then analyze the response 3 times)
Willy Tarreaued179852013-12-16 01:07:00 +01009660 option tcp-check
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009661 tcp-check comment PING\ phase
Willy Tarreaued179852013-12-16 01:07:00 +01009662 tcp-check send PING\r\n
Baptiste Assmanna3322992015-08-04 10:12:18 +02009663 tcp-check expect string +PONG
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009664 tcp-check comment role\ check
Willy Tarreaued179852013-12-16 01:07:00 +01009665 tcp-check send info\ replication\r\n
9666 tcp-check expect string role:master
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009667 tcp-check comment QUIT\ phase
Willy Tarreaued179852013-12-16 01:07:00 +01009668 tcp-check send QUIT\r\n
9669 tcp-check expect string +OK
9670
Davor Ocelice9ed2812017-12-25 17:49:28 +01009671 forge a HTTP request, then analyze the response
Willy Tarreaued179852013-12-16 01:07:00 +01009672 (send many headers before analyzing)
9673 option tcp-check
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009674 tcp-check comment forge\ and\ send\ HTTP\ request
Willy Tarreaued179852013-12-16 01:07:00 +01009675 tcp-check send HEAD\ /\ HTTP/1.1\r\n
9676 tcp-check send Host:\ www.mydomain.com\r\n
9677 tcp-check send User-Agent:\ HAProxy\ tcpcheck\r\n
9678 tcp-check send \r\n
Baptiste Assmannd60a9e52015-04-25 16:27:23 +02009679 tcp-check expect rstring HTTP/1\..\ (2..|3..) comment check\ HTTP\ response
Willy Tarreaued179852013-12-16 01:07:00 +01009680
9681
Christopher Fauletc52ea4d2020-04-23 15:43:35 +02009682 See also : "tcp-check connect", "tcp-check expect" and "tcp-check send".
Willy Tarreaued179852013-12-16 01:07:00 +01009683
9684
Willy Tarreau9ea05a72009-06-14 12:07:01 +02009685option tcp-smart-accept
9686no option tcp-smart-accept
9687 Enable or disable the saving of one ACK packet during the accept sequence
9688 May be used in sections : defaults | frontend | listen | backend
9689 yes | yes | yes | no
9690 Arguments : none
9691
9692 When an HTTP connection request comes in, the system acknowledges it on
9693 behalf of HAProxy, then the client immediately sends its request, and the
9694 system acknowledges it too while it is notifying HAProxy about the new
9695 connection. HAProxy then reads the request and responds. This means that we
9696 have one TCP ACK sent by the system for nothing, because the request could
9697 very well be acknowledged by HAProxy when it sends its response.
9698
9699 For this reason, in HTTP mode, HAProxy automatically asks the system to avoid
9700 sending this useless ACK on platforms which support it (currently at least
9701 Linux). It must not cause any problem, because the system will send it anyway
9702 after 40 ms if the response takes more time than expected to come.
9703
9704 During complex network debugging sessions, it may be desirable to disable
9705 this optimization because delayed ACKs can make troubleshooting more complex
9706 when trying to identify where packets are delayed. It is then possible to
Davor Ocelice9ed2812017-12-25 17:49:28 +01009707 fall back to normal behavior by specifying "no option tcp-smart-accept".
Willy Tarreau9ea05a72009-06-14 12:07:01 +02009708
9709 It is also possible to force it for non-HTTP proxies by simply specifying
9710 "option tcp-smart-accept". For instance, it can make sense with some services
9711 such as SMTP where the server speaks first.
9712
9713 It is recommended to avoid forcing this option in a defaults section. In case
9714 of doubt, consider setting it back to automatic values by prepending the
9715 "default" keyword before it, or disabling it using the "no" keyword.
9716
Willy Tarreaud88edf22009-06-14 15:48:17 +02009717 See also : "option tcp-smart-connect"
9718
9719
9720option tcp-smart-connect
9721no option tcp-smart-connect
9722 Enable or disable the saving of one ACK packet during the connect sequence
9723 May be used in sections : defaults | frontend | listen | backend
9724 yes | no | yes | yes
9725 Arguments : none
9726
9727 On certain systems (at least Linux), HAProxy can ask the kernel not to
9728 immediately send an empty ACK upon a connection request, but to directly
9729 send the buffer request instead. This saves one packet on the network and
9730 thus boosts performance. It can also be useful for some servers, because they
9731 immediately get the request along with the incoming connection.
9732
9733 This feature is enabled when "option tcp-smart-connect" is set in a backend.
9734 It is not enabled by default because it makes network troubleshooting more
9735 complex.
9736
9737 It only makes sense to enable it with protocols where the client speaks first
9738 such as HTTP. In other situations, if there is no data to send in place of
9739 the ACK, a normal ACK is sent.
9740
9741 If this option has been enabled in a "defaults" section, it can be disabled
9742 in a specific instance by prepending the "no" keyword before it.
9743
9744 See also : "option tcp-smart-accept"
9745
Willy Tarreau9ea05a72009-06-14 12:07:01 +02009746
Willy Tarreaubf1f8162007-12-28 17:42:56 +01009747option tcpka
9748 Enable or disable the sending of TCP keepalive packets on both sides
9749 May be used in sections : defaults | frontend | listen | backend
9750 yes | yes | yes | yes
9751 Arguments : none
9752
9753 When there is a firewall or any session-aware component between a client and
9754 a server, and when the protocol involves very long sessions with long idle
Davor Ocelice9ed2812017-12-25 17:49:28 +01009755 periods (e.g. remote desktops), there is a risk that one of the intermediate
Willy Tarreaubf1f8162007-12-28 17:42:56 +01009756 components decides to expire a session which has remained idle for too long.
9757
9758 Enabling socket-level TCP keep-alives makes the system regularly send packets
9759 to the other end of the connection, leaving it active. The delay between
9760 keep-alive probes is controlled by the system only and depends both on the
9761 operating system and its tuning parameters.
9762
9763 It is important to understand that keep-alive packets are neither emitted nor
9764 received at the application level. It is only the network stacks which sees
9765 them. For this reason, even if one side of the proxy already uses keep-alives
9766 to maintain its connection alive, those keep-alive packets will not be
9767 forwarded to the other side of the proxy.
9768
9769 Please note that this has nothing to do with HTTP keep-alive.
9770
9771 Using option "tcpka" enables the emission of TCP keep-alive probes on both
9772 the client and server sides of a connection. Note that this is meaningful
9773 only in "defaults" or "listen" sections. If this option is used in a
9774 frontend, only the client side will get keep-alives, and if this option is
9775 used in a backend, only the server side will get keep-alives. For this
9776 reason, it is strongly recommended to explicitly use "option clitcpka" and
9777 "option srvtcpka" when the configuration is split between frontends and
9778 backends.
9779
9780 See also : "option clitcpka", "option srvtcpka"
9781
Willy Tarreau844e3c52008-01-11 16:28:18 +01009782
9783option tcplog
9784 Enable advanced logging of TCP connections with session state and timers
9785 May be used in sections : defaults | frontend | listen | backend
Tim Duesterhus9ad9f352018-02-05 20:52:27 +01009786 yes | yes | yes | no
Willy Tarreau844e3c52008-01-11 16:28:18 +01009787 Arguments : none
9788
9789 By default, the log output format is very poor, as it only contains the
9790 source and destination addresses, and the instance name. By specifying
9791 "option tcplog", each log line turns into a much richer format including, but
9792 not limited to, the connection timers, the session status, the connections
9793 numbers, the frontend, backend and server name, and of course the source
9794 address and ports. This option is useful for pure TCP proxies in order to
9795 find which of the client or server disconnects or times out. For normal HTTP
9796 proxies, it's better to use "option httplog" which is even more complete.
9797
Guillaume de Lafond29f45602017-03-31 19:52:15 +02009798 "option tcplog" overrides any previous "log-format" directive.
9799
Willy Tarreauc57f0e22009-05-10 13:12:33 +02009800 See also : "option httplog", and section 8 about logging.
Willy Tarreau844e3c52008-01-11 16:28:18 +01009801
9802
Willy Tarreau844e3c52008-01-11 16:28:18 +01009803option transparent
9804no option transparent
9805 Enable client-side transparent proxying
9806 May be used in sections : defaults | frontend | listen | backend
Willy Tarreau4b1f8592008-12-23 23:13:55 +01009807 yes | no | yes | yes
Willy Tarreau844e3c52008-01-11 16:28:18 +01009808 Arguments : none
9809
9810 This option was introduced in order to provide layer 7 persistence to layer 3
9811 load balancers. The idea is to use the OS's ability to redirect an incoming
9812 connection for a remote address to a local process (here HAProxy), and let
9813 this process know what address was initially requested. When this option is
9814 used, sessions without cookies will be forwarded to the original destination
9815 IP address of the incoming request (which should match that of another
9816 equipment), while requests with cookies will still be forwarded to the
9817 appropriate server.
9818
9819 Note that contrary to a common belief, this option does NOT make HAProxy
9820 present the client's IP to the server when establishing the connection.
9821
Willy Tarreaua1146052011-03-01 09:51:54 +01009822 See also: the "usesrc" argument of the "source" keyword, and the
Willy Tarreaueabeafa2008-01-16 16:17:06 +01009823 "transparent" option of the "bind" keyword.
Willy Tarreau844e3c52008-01-11 16:28:18 +01009824
Willy Tarreaubf1f8162007-12-28 17:42:56 +01009825
Simon Horman98637e52014-06-20 12:30:16 +09009826external-check command <command>
9827 Executable to run when performing an external-check
9828 May be used in sections : defaults | frontend | listen | backend
9829 yes | no | yes | yes
9830
9831 Arguments :
9832 <command> is the external command to run
9833
Simon Horman98637e52014-06-20 12:30:16 +09009834 The arguments passed to the to the command are:
9835
Cyril Bonté777be862014-12-02 21:21:35 +01009836 <proxy_address> <proxy_port> <server_address> <server_port>
Simon Horman98637e52014-06-20 12:30:16 +09009837
Cyril Bonté777be862014-12-02 21:21:35 +01009838 The <proxy_address> and <proxy_port> are derived from the first listener
9839 that is either IPv4, IPv6 or a UNIX socket. In the case of a UNIX socket
9840 listener the proxy_address will be the path of the socket and the
9841 <proxy_port> will be the string "NOT_USED". In a backend section, it's not
9842 possible to determine a listener, and both <proxy_address> and <proxy_port>
9843 will have the string value "NOT_USED".
Simon Horman98637e52014-06-20 12:30:16 +09009844
Cyril Bonté72cda2a2014-12-27 22:28:39 +01009845 Some values are also provided through environment variables.
9846
9847 Environment variables :
9848 HAPROXY_PROXY_ADDR The first bind address if available (or empty if not
9849 applicable, for example in a "backend" section).
9850
9851 HAPROXY_PROXY_ID The backend id.
9852
9853 HAPROXY_PROXY_NAME The backend name.
9854
9855 HAPROXY_PROXY_PORT The first bind port if available (or empty if not
9856 applicable, for example in a "backend" section or
9857 for a UNIX socket).
9858
9859 HAPROXY_SERVER_ADDR The server address.
9860
9861 HAPROXY_SERVER_CURCONN The current number of connections on the server.
9862
9863 HAPROXY_SERVER_ID The server id.
9864
9865 HAPROXY_SERVER_MAXCONN The server max connections.
9866
9867 HAPROXY_SERVER_NAME The server name.
9868
9869 HAPROXY_SERVER_PORT The server port if available (or empty for a UNIX
9870 socket).
9871
9872 PATH The PATH environment variable used when executing
9873 the command may be set using "external-check path".
9874
William Lallemand4d03e432019-06-14 15:35:37 +02009875 See also "2.3. Environment variables" for other variables.
9876
Simon Horman98637e52014-06-20 12:30:16 +09009877 If the command executed and exits with a zero status then the check is
9878 considered to have passed, otherwise the check is considered to have
9879 failed.
9880
9881 Example :
9882 external-check command /bin/true
9883
9884 See also : "external-check", "option external-check", "external-check path"
9885
9886
9887external-check path <path>
9888 The value of the PATH environment variable used when running an external-check
9889 May be used in sections : defaults | frontend | listen | backend
9890 yes | no | yes | yes
9891
9892 Arguments :
9893 <path> is the path used when executing external command to run
9894
9895 The default path is "".
9896
9897 Example :
9898 external-check path "/usr/bin:/bin"
9899
9900 See also : "external-check", "option external-check",
9901 "external-check command"
9902
9903
Emeric Brun647caf12009-06-30 17:57:00 +02009904persist rdp-cookie
Hervé COMMOWICKa3eb39c2011-08-05 18:48:51 +02009905persist rdp-cookie(<name>)
Emeric Brun647caf12009-06-30 17:57:00 +02009906 Enable RDP cookie-based persistence
9907 May be used in sections : defaults | frontend | listen | backend
9908 yes | no | yes | yes
9909 Arguments :
9910 <name> is the optional name of the RDP cookie to check. If omitted, the
Willy Tarreau61e28f22010-05-16 22:31:05 +02009911 default cookie name "msts" will be used. There currently is no
9912 valid reason to change this name.
Emeric Brun647caf12009-06-30 17:57:00 +02009913
9914 This statement enables persistence based on an RDP cookie. The RDP cookie
9915 contains all information required to find the server in the list of known
Davor Ocelice9ed2812017-12-25 17:49:28 +01009916 servers. So when this option is set in the backend, the request is analyzed
Emeric Brun647caf12009-06-30 17:57:00 +02009917 and if an RDP cookie is found, it is decoded. If it matches a known server
9918 which is still UP (or if "option persist" is set), then the connection is
9919 forwarded to this server.
9920
9921 Note that this only makes sense in a TCP backend, but for this to work, the
9922 frontend must have waited long enough to ensure that an RDP cookie is present
9923 in the request buffer. This is the same requirement as with the "rdp-cookie"
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +01009924 load-balancing method. Thus it is highly recommended to put all statements in
Emeric Brun647caf12009-06-30 17:57:00 +02009925 a single "listen" section.
9926
Willy Tarreau61e28f22010-05-16 22:31:05 +02009927 Also, it is important to understand that the terminal server will emit this
9928 RDP cookie only if it is configured for "token redirection mode", which means
9929 that the "IP address redirection" option is disabled.
9930
Emeric Brun647caf12009-06-30 17:57:00 +02009931 Example :
9932 listen tse-farm
9933 bind :3389
9934 # wait up to 5s for an RDP cookie in the request
9935 tcp-request inspect-delay 5s
9936 tcp-request content accept if RDP_COOKIE
9937 # apply RDP cookie persistence
9938 persist rdp-cookie
9939 # if server is unknown, let's balance on the same cookie.
Cyril Bontédc4d9032012-04-08 21:57:39 +02009940 # alternatively, "balance leastconn" may be useful too.
Emeric Brun647caf12009-06-30 17:57:00 +02009941 balance rdp-cookie
9942 server srv1 1.1.1.1:3389
9943 server srv2 1.1.1.2:3389
9944
Simon Hormanab814e02011-06-24 14:50:20 +09009945 See also : "balance rdp-cookie", "tcp-request", the "req_rdp_cookie" ACL and
9946 the rdp_cookie pattern fetch function.
Emeric Brun647caf12009-06-30 17:57:00 +02009947
9948
Willy Tarreau3a7d2072009-03-05 23:48:25 +01009949rate-limit sessions <rate>
9950 Set a limit on the number of new sessions accepted per second on a frontend
9951 May be used in sections : defaults | frontend | listen | backend
9952 yes | yes | yes | no
9953 Arguments :
9954 <rate> The <rate> parameter is an integer designating the maximum number
9955 of new sessions per second to accept on the frontend.
9956
9957 When the frontend reaches the specified number of new sessions per second, it
9958 stops accepting new connections until the rate drops below the limit again.
9959 During this time, the pending sessions will be kept in the socket's backlog
Daniel Corbett9f0843f2021-05-08 10:50:37 -04009960 (in system buffers) and HAProxy will not even be aware that sessions are
Willy Tarreau3a7d2072009-03-05 23:48:25 +01009961 pending. When applying very low limit on a highly loaded service, it may make
9962 sense to increase the socket's backlog using the "backlog" keyword.
9963
9964 This feature is particularly efficient at blocking connection-based attacks
9965 or service abuse on fragile servers. Since the session rate is measured every
9966 millisecond, it is extremely accurate. Also, the limit applies immediately,
9967 no delay is needed at all to detect the threshold.
9968
9969 Example : limit the connection rate on SMTP to 10 per second max
9970 listen smtp
9971 mode tcp
9972 bind :25
9973 rate-limit sessions 10
Panagiotis Panagiotopoulos7282d8e2016-02-11 16:37:15 +02009974 server smtp1 127.0.0.1:1025
Willy Tarreau3a7d2072009-03-05 23:48:25 +01009975
Willy Tarreaua17c2d92011-07-25 08:16:20 +02009976 Note : when the maximum rate is reached, the frontend's status is not changed
9977 but its sockets appear as "WAITING" in the statistics if the
9978 "socket-stats" option is enabled.
Willy Tarreau3a7d2072009-03-05 23:48:25 +01009979
9980 See also : the "backlog" keyword and the "fe_sess_rate" ACL criterion.
9981
9982
Willy Tarreau2e1dca82012-09-12 08:43:15 +02009983redirect location <loc> [code <code>] <option> [{if | unless} <condition>]
9984redirect prefix <pfx> [code <code>] <option> [{if | unless} <condition>]
9985redirect scheme <sch> [code <code>] <option> [{if | unless} <condition>]
Willy Tarreaub463dfb2008-06-07 23:08:56 +02009986 Return an HTTP redirection if/unless a condition is matched
9987 May be used in sections : defaults | frontend | listen | backend
9988 no | yes | yes | yes
9989
9990 If/unless the condition is matched, the HTTP request will lead to a redirect
Willy Tarreauf285f542010-01-03 20:03:03 +01009991 response. If no condition is specified, the redirect applies unconditionally.
Willy Tarreaub463dfb2008-06-07 23:08:56 +02009992
Willy Tarreau0140f252008-11-19 21:07:09 +01009993 Arguments :
Willy Tarreau2e1dca82012-09-12 08:43:15 +02009994 <loc> With "redirect location", the exact value in <loc> is placed into
Thierry FOURNIERd18cd0f2013-11-29 12:15:45 +01009995 the HTTP "Location" header. When used in an "http-request" rule,
9996 <loc> value follows the log-format rules and can include some
9997 dynamic values (see Custom Log Format in section 8.2.4).
Willy Tarreau2e1dca82012-09-12 08:43:15 +02009998
9999 <pfx> With "redirect prefix", the "Location" header is built from the
10000 concatenation of <pfx> and the complete URI path, including the
10001 query string, unless the "drop-query" option is specified (see
10002 below). As a special case, if <pfx> equals exactly "/", then
10003 nothing is inserted before the original URI. It allows one to
Thierry FOURNIERd18cd0f2013-11-29 12:15:45 +010010004 redirect to the same URL (for instance, to insert a cookie). When
10005 used in an "http-request" rule, <pfx> value follows the log-format
10006 rules and can include some dynamic values (see Custom Log Format
10007 in section 8.2.4).
Willy Tarreau2e1dca82012-09-12 08:43:15 +020010008
10009 <sch> With "redirect scheme", then the "Location" header is built by
10010 concatenating <sch> with "://" then the first occurrence of the
10011 "Host" header, and then the URI path, including the query string
10012 unless the "drop-query" option is specified (see below). If no
10013 path is found or if the path is "*", then "/" is used instead. If
10014 no "Host" header is found, then an empty host component will be
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030010015 returned, which most recent browsers interpret as redirecting to
Willy Tarreau2e1dca82012-09-12 08:43:15 +020010016 the same host. This directive is mostly used to redirect HTTP to
Thierry FOURNIERd18cd0f2013-11-29 12:15:45 +010010017 HTTPS. When used in an "http-request" rule, <sch> value follows
10018 the log-format rules and can include some dynamic values (see
10019 Custom Log Format in section 8.2.4).
Willy Tarreau0140f252008-11-19 21:07:09 +010010020
10021 <code> The code is optional. It indicates which type of HTTP redirection
Willy Tarreaub67fdc42013-03-29 19:28:11 +010010022 is desired. Only codes 301, 302, 303, 307 and 308 are supported,
10023 with 302 used by default if no code is specified. 301 means
10024 "Moved permanently", and a browser may cache the Location. 302
Baptiste Assmannea849c02015-08-03 11:42:50 +020010025 means "Moved temporarily" and means that the browser should not
Willy Tarreaub67fdc42013-03-29 19:28:11 +010010026 cache the redirection. 303 is equivalent to 302 except that the
10027 browser will fetch the location with a GET method. 307 is just
10028 like 302 but makes it clear that the same method must be reused.
10029 Likewise, 308 replaces 301 if the same method must be used.
Willy Tarreau0140f252008-11-19 21:07:09 +010010030
10031 <option> There are several options which can be specified to adjust the
Davor Ocelice9ed2812017-12-25 17:49:28 +010010032 expected behavior of a redirection :
Willy Tarreau0140f252008-11-19 21:07:09 +010010033
10034 - "drop-query"
10035 When this keyword is used in a prefix-based redirection, then the
10036 location will be set without any possible query-string, which is useful
10037 for directing users to a non-secure page for instance. It has no effect
10038 with a location-type redirect.
10039
Willy Tarreau81e3b4f2010-01-10 00:42:19 +010010040 - "append-slash"
10041 This keyword may be used in conjunction with "drop-query" to redirect
10042 users who use a URL not ending with a '/' to the same one with the '/'.
10043 It can be useful to ensure that search engines will only see one URL.
10044 For this, a return code 301 is preferred.
10045
Willy Tarreau0140f252008-11-19 21:07:09 +010010046 - "set-cookie NAME[=value]"
10047 A "Set-Cookie" header will be added with NAME (and optionally "=value")
10048 to the response. This is sometimes used to indicate that a user has
10049 been seen, for instance to protect against some types of DoS. No other
10050 cookie option is added, so the cookie will be a session cookie. Note
10051 that for a browser, a sole cookie name without an equal sign is
10052 different from a cookie with an equal sign.
10053
10054 - "clear-cookie NAME[=]"
10055 A "Set-Cookie" header will be added with NAME (and optionally "="), but
10056 with the "Max-Age" attribute set to zero. This will tell the browser to
10057 delete this cookie. It is useful for instance on logout pages. It is
10058 important to note that clearing the cookie "NAME" will not remove a
10059 cookie set with "NAME=value". You have to clear the cookie "NAME=" for
10060 that, because the browser makes the difference.
Willy Tarreaub463dfb2008-06-07 23:08:56 +020010061
10062 Example: move the login URL only to HTTPS.
10063 acl clear dst_port 80
10064 acl secure dst_port 8080
10065 acl login_page url_beg /login
Willy Tarreau0140f252008-11-19 21:07:09 +010010066 acl logout url_beg /logout
Willy Tarreau79da4692008-11-19 20:03:04 +010010067 acl uid_given url_reg /login?userid=[^&]+
Willy Tarreau0140f252008-11-19 21:07:09 +010010068 acl cookie_set hdr_sub(cookie) SEEN=1
10069
10070 redirect prefix https://mysite.com set-cookie SEEN=1 if !cookie_set
Willy Tarreau79da4692008-11-19 20:03:04 +010010071 redirect prefix https://mysite.com if login_page !secure
10072 redirect prefix http://mysite.com drop-query if login_page !uid_given
10073 redirect location http://mysite.com/ if !login_page secure
Willy Tarreau0140f252008-11-19 21:07:09 +010010074 redirect location / clear-cookie USERID= if logout
Willy Tarreaub463dfb2008-06-07 23:08:56 +020010075
Willy Tarreau81e3b4f2010-01-10 00:42:19 +010010076 Example: send redirects for request for articles without a '/'.
10077 acl missing_slash path_reg ^/article/[^/]*$
10078 redirect code 301 prefix / drop-query append-slash if missing_slash
10079
Daniel Corbett9f0843f2021-05-08 10:50:37 -040010080 Example: redirect all HTTP traffic to HTTPS when SSL is handled by HAProxy.
David BERARDe7153042012-11-03 00:11:31 +010010081 redirect scheme https if !{ ssl_fc }
Willy Tarreau2e1dca82012-09-12 08:43:15 +020010082
Thierry FOURNIERd18cd0f2013-11-29 12:15:45 +010010083 Example: append 'www.' prefix in front of all hosts not having it
Coen Rosdorff596659b2016-04-11 11:33:49 +020010084 http-request redirect code 301 location \
10085 http://www.%[hdr(host)]%[capture.req.uri] \
10086 unless { hdr_beg(host) -i www }
Thierry FOURNIERd18cd0f2013-11-29 12:15:45 +010010087
Willy Tarreauc57f0e22009-05-10 13:12:33 +020010088 See section 7 about ACL usage.
Willy Tarreaub463dfb2008-06-07 23:08:56 +020010089
Willy Tarreau303c0352008-01-17 19:01:39 +010010090
Willy Tarreaue5c5ce92008-06-20 17:27:19 +020010091retries <value>
10092 Set the number of retries to perform on a server after a connection failure
10093 May be used in sections: defaults | frontend | listen | backend
10094 yes | no | yes | yes
10095 Arguments :
10096 <value> is the number of times a connection attempt should be retried on
10097 a server when a connection either is refused or times out. The
10098 default value is 3.
10099
10100 It is important to understand that this value applies to the number of
10101 connection attempts, not full requests. When a connection has effectively
10102 been established to a server, there will be no more retry.
10103
10104 In order to avoid immediate reconnections to a server which is restarting,
Joseph Lynch726ab712015-05-11 23:25:34 -070010105 a turn-around timer of min("timeout connect", one second) is applied before
10106 a retry occurs.
Willy Tarreaue5c5ce92008-06-20 17:27:19 +020010107
10108 When "option redispatch" is set, the last retry may be performed on another
10109 server even if a cookie references a different server.
10110
10111 See also : "option redispatch"
10112
10113
Olivier Houcharda254a372019-04-05 15:30:12 +020010114retry-on [list of keywords]
Jerome Magnin5ce3c142020-05-13 20:09:57 +020010115 Specify when to attempt to automatically retry a failed request.
10116 This setting is only valid when "mode" is set to http and is silently ignored
10117 otherwise.
Olivier Houcharda254a372019-04-05 15:30:12 +020010118 May be used in sections: defaults | frontend | listen | backend
10119 yes | no | yes | yes
10120 Arguments :
10121 <keywords> is a list of keywords or HTTP status codes, each representing a
10122 type of failure event on which an attempt to retry the request
10123 is desired. Please read the notes at the bottom before changing
10124 this setting. The following keywords are supported :
10125
10126 none never retry
10127
10128 conn-failure retry when the connection or the SSL handshake failed
10129 and the request could not be sent. This is the default.
10130
10131 empty-response retry when the server connection was closed after part
10132 of the request was sent, and nothing was received from
10133 the server. This type of failure may be caused by the
10134 request timeout on the server side, poor network
10135 condition, or a server crash or restart while
10136 processing the request.
10137
Olivier Houcharde3249a92019-05-03 23:01:47 +020010138 junk-response retry when the server returned something not looking
10139 like a complete HTTP response. This includes partial
10140 responses headers as well as non-HTTP contents. It
10141 usually is a bad idea to retry on such events, which
10142 may be caused a configuration issue (wrong server port)
10143 or by the request being harmful to the server (buffer
10144 overflow attack for example).
10145
Olivier Houcharda254a372019-04-05 15:30:12 +020010146 response-timeout the server timeout stroke while waiting for the server
10147 to respond to the request. This may be caused by poor
10148 network condition, the reuse of an idle connection
10149 which has expired on the path, or by the request being
10150 extremely expensive to process. It generally is a bad
10151 idea to retry on such events on servers dealing with
10152 heavy database processing (full scans, etc) as it may
10153 amplify denial of service attacks.
10154
Olivier Houchard865d8392019-05-03 22:46:27 +020010155 0rtt-rejected retry requests which were sent over early data and were
10156 rejected by the server. These requests are generally
10157 considered to be safe to retry.
10158
Julien Pivotto2de240a2020-11-12 11:14:05 +010010159 <status> any HTTP status code among "401" (Unauthorized), "403"
10160 (Forbidden), "404" (Not Found), "408" (Request Timeout),
10161 "425" (Too Early), "500" (Server Error), "501" (Not
10162 Implemented), "502" (Bad Gateway), "503" (Service
10163 Unavailable), "504" (Gateway Timeout).
Olivier Houcharda254a372019-04-05 15:30:12 +020010164
Olivier Houchardddf0e032019-05-10 18:05:40 +020010165 all-retryable-errors
10166 retry request for any error that are considered
10167 retryable. This currently activates "conn-failure",
10168 "empty-response", "junk-response", "response-timeout",
10169 "0rtt-rejected", "500", "502", "503", and "504".
10170
Olivier Houcharda254a372019-04-05 15:30:12 +020010171 Using this directive replaces any previous settings with the new ones; it is
10172 not cumulative.
10173
10174 Please note that using anything other than "none" and "conn-failure" requires
10175 to allocate a buffer and copy the whole request into it, so it has memory and
10176 performance impacts. Requests not fitting in a single buffer will never be
10177 retried (see the global tune.bufsize setting).
10178
10179 You have to make sure the application has a replay protection mechanism built
10180 in such as a unique transaction IDs passed in requests, or that replaying the
10181 same request has no consequence, or it is very dangerous to use any retry-on
10182 value beside "conn-failure" and "none". Static file servers and caches are
10183 generally considered safe against any type of retry. Using a status code can
10184 be useful to quickly leave a server showing an abnormal behavior (out of
10185 memory, file system issues, etc), but in this case it may be a good idea to
10186 immediately redispatch the connection to another server (please see "option
10187 redispatch" for this). Last, it is important to understand that most causes
10188 of failures are the requests themselves and that retrying a request causing a
10189 server to misbehave will often make the situation even worse for this server,
10190 or for the whole service in case of redispatch.
10191
10192 Unless you know exactly how the application deals with replayed requests, you
10193 should not use this directive.
10194
10195 The default is "conn-failure".
10196
10197 See also: "retries", "option redispatch", "tune.bufsize"
10198
David du Colombier486df472011-03-17 10:40:26 +010010199server <name> <address>[:[port]] [param*]
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010200 Declare a server in a backend
10201 May be used in sections : defaults | frontend | listen | backend
10202 no | no | yes | yes
10203 Arguments :
10204 <name> is the internal name assigned to this server. This name will
Davor Ocelice9ed2812017-12-25 17:49:28 +010010205 appear in logs and alerts. If "http-send-name-header" is
Mark Lamourinec2247f02012-01-04 13:02:01 -050010206 set, it will be added to the request header sent to the server.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010207
David du Colombier486df472011-03-17 10:40:26 +010010208 <address> is the IPv4 or IPv6 address of the server. Alternatively, a
10209 resolvable hostname is supported, but this name will be resolved
10210 during start-up. Address "0.0.0.0" or "*" has a special meaning.
10211 It indicates that the connection will be forwarded to the same IP
Willy Tarreaud669a4f2010-07-13 14:49:50 +020010212 address as the one from the client connection. This is useful in
10213 transparent proxy architectures where the client's connection is
Daniel Corbett9f0843f2021-05-08 10:50:37 -040010214 intercepted and HAProxy must forward to the original destination
Willy Tarreaud669a4f2010-07-13 14:49:50 +020010215 address. This is more or less what the "transparent" keyword does
10216 except that with a server it's possible to limit concurrency and
Willy Tarreau24709282013-03-10 21:32:12 +010010217 to report statistics. Optionally, an address family prefix may be
10218 used before the address to force the family regardless of the
10219 address format, which can be useful to specify a path to a unix
10220 socket with no slash ('/'). Currently supported prefixes are :
10221 - 'ipv4@' -> address is always IPv4
10222 - 'ipv6@' -> address is always IPv6
10223 - 'unix@' -> address is a path to a local unix socket
Willy Tarreauccfccef2014-05-10 01:49:15 +020010224 - 'abns@' -> address is in abstract namespace (Linux only)
William Lallemand2fe7dd02018-09-11 16:51:29 +020010225 - 'sockpair@' -> address is the FD of a connected unix
10226 socket or of a socketpair. During a connection, the
10227 backend creates a pair of connected sockets, and passes
10228 one of them over the FD. The bind part will use the
10229 received socket as the client FD. Should be used
10230 carefully.
William Lallemandb2f07452015-05-12 14:27:13 +020010231 You may want to reference some environment variables in the
10232 address parameter, see section 2.3 about environment
Willy Tarreau6a031d12016-11-07 19:42:35 +010010233 variables. The "init-addr" setting can be used to modify the way
10234 IP addresses should be resolved upon startup.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010235
Willy Tarreaub6205fd2012-09-24 12:27:33 +020010236 <port> is an optional port specification. If set, all connections will
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010237 be sent to this port. If unset, the same port the client
10238 connected to will be used. The port may also be prefixed by a "+"
10239 or a "-". In this case, the server's port will be determined by
10240 adding this value to the client's port.
10241
10242 <param*> is a list of parameters for this server. The "server" keywords
10243 accepts an important number of options and has a complete section
Willy Tarreauc57f0e22009-05-10 13:12:33 +020010244 dedicated to it. Please refer to section 5 for more details.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010245
10246 Examples :
10247 server first 10.1.1.1:1080 cookie first check inter 1000
10248 server second 10.1.1.2:1080 cookie second check inter 1000
Willy Tarreau24709282013-03-10 21:32:12 +010010249 server transp ipv4@
William Lallemandb2f07452015-05-12 14:27:13 +020010250 server backup "${SRV_BACKUP}:1080" backup
10251 server www1_dc1 "${LAN_DC1}.101:80"
10252 server www1_dc2 "${LAN_DC2}.101:80"
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010253
Willy Tarreau55dcaf62015-09-27 15:03:15 +020010254 Note: regarding Linux's abstract namespace sockets, HAProxy uses the whole
10255 sun_path length is used for the address length. Some other programs
10256 such as socat use the string length only by default. Pass the option
10257 ",unix-tightsocklen=0" to any abstract socket definition in socat to
10258 make it compatible with HAProxy's.
10259
Mark Lamourinec2247f02012-01-04 13:02:01 -050010260 See also: "default-server", "http-send-name-header" and section 5 about
10261 server options
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010262
Christopher Faulet583b6de2021-02-12 09:27:10 +010010263server-state-file-name [ { use-backend-name | <file> } ]
Baptiste Assmann01c6cc32015-08-23 11:45:29 +020010264 Set the server state file to read, load and apply to servers available in
Christopher Faulet583b6de2021-02-12 09:27:10 +010010265 this backend.
10266 May be used in sections: defaults | frontend | listen | backend
10267 no | no | yes | yes
10268
10269 It only applies when the directive "load-server-state-from-file" is set to
10270 "local". When <file> is not provided, if "use-backend-name" is used or if
10271 this directive is not set, then backend name is used. If <file> starts with a
10272 slash '/', then it is considered as an absolute path. Otherwise, <file> is
10273 concatenated to the global directive "server-state-base".
Baptiste Assmann01c6cc32015-08-23 11:45:29 +020010274
10275 Example: the minimal configuration below would make HAProxy look for the
10276 state server file '/etc/haproxy/states/bk':
10277
10278 global
10279 server-state-file-base /etc/haproxy/states
10280
Willy Tarreauc9c6cdb2020-03-05 16:03:58 +010010281 backend bk
Baptiste Assmann01c6cc32015-08-23 11:45:29 +020010282 load-server-state-from-file
10283
Christopher Faulet583b6de2021-02-12 09:27:10 +010010284 See also: "server-state-base", "load-server-state-from-file", and
Baptiste Assmann01c6cc32015-08-23 11:45:29 +020010285 "show servers state"
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010286
Frédéric Lécaillecb4502e2017-04-20 13:36:25 +020010287server-template <prefix> <num | range> <fqdn>[:<port>] [params*]
10288 Set a template to initialize servers with shared parameters.
10289 The names of these servers are built from <prefix> and <num | range> parameters.
10290 May be used in sections : defaults | frontend | listen | backend
10291 no | no | yes | yes
10292
10293 Arguments:
10294 <prefix> A prefix for the server names to be built.
10295
10296 <num | range>
10297 If <num> is provided, this template initializes <num> servers
10298 with 1 up to <num> as server name suffixes. A range of numbers
10299 <num_low>-<num_high> may also be used to use <num_low> up to
10300 <num_high> as server name suffixes.
10301
10302 <fqdn> A FQDN for all the servers this template initializes.
10303
10304 <port> Same meaning as "server" <port> argument (see "server" keyword).
10305
10306 <params*>
10307 Remaining server parameters among all those supported by "server"
10308 keyword.
10309
10310 Examples:
10311 # Initializes 3 servers with srv1, srv2 and srv3 as names,
10312 # google.com as FQDN, and health-check enabled.
10313 server-template srv 1-3 google.com:80 check
10314
10315 # or
10316 server-template srv 3 google.com:80 check
10317
10318 # would be equivalent to:
10319 server srv1 google.com:80 check
10320 server srv2 google.com:80 check
10321 server srv3 google.com:80 check
10322
10323
10324
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010325source <addr>[:<port>] [usesrc { <addr2>[:<port2>] | client | clientip } ]
Willy Tarreaubce70882009-09-07 11:51:47 +020010326source <addr>[:<port>] [usesrc { <addr2>[:<port2>] | hdr_ip(<hdr>[,<occ>]) } ]
Willy Tarreaud53f96b2009-02-04 18:46:54 +010010327source <addr>[:<port>] [interface <name>]
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010328 Set the source address for outgoing connections
10329 May be used in sections : defaults | frontend | listen | backend
10330 yes | no | yes | yes
10331 Arguments :
10332 <addr> is the IPv4 address HAProxy will bind to before connecting to a
10333 server. This address is also used as a source for health checks.
Willy Tarreau24709282013-03-10 21:32:12 +010010334
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010335 The default value of 0.0.0.0 means that the system will select
Willy Tarreau24709282013-03-10 21:32:12 +010010336 the most appropriate address to reach its destination. Optionally
10337 an address family prefix may be used before the address to force
10338 the family regardless of the address format, which can be useful
10339 to specify a path to a unix socket with no slash ('/'). Currently
10340 supported prefixes are :
10341 - 'ipv4@' -> address is always IPv4
10342 - 'ipv6@' -> address is always IPv6
10343 - 'unix@' -> address is a path to a local unix socket
Willy Tarreauccfccef2014-05-10 01:49:15 +020010344 - 'abns@' -> address is in abstract namespace (Linux only)
Cyril Bonté307ee1e2015-09-28 23:16:06 +020010345 You may want to reference some environment variables in the
10346 address parameter, see section 2.3 about environment variables.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010347
10348 <port> is an optional port. It is normally not needed but may be useful
10349 in some very specific contexts. The default value of zero means
Willy Tarreauc6f4ce82009-06-10 11:09:37 +020010350 the system will select a free port. Note that port ranges are not
10351 supported in the backend. If you want to force port ranges, you
10352 have to specify them on each "server" line.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010353
10354 <addr2> is the IP address to present to the server when connections are
10355 forwarded in full transparent proxy mode. This is currently only
10356 supported on some patched Linux kernels. When this address is
10357 specified, clients connecting to the server will be presented
10358 with this address, while health checks will still use the address
10359 <addr>.
10360
10361 <port2> is the optional port to present to the server when connections
10362 are forwarded in full transparent proxy mode (see <addr2> above).
10363 The default value of zero means the system will select a free
10364 port.
10365
Willy Tarreaubce70882009-09-07 11:51:47 +020010366 <hdr> is the name of a HTTP header in which to fetch the IP to bind to.
10367 This is the name of a comma-separated header list which can
10368 contain multiple IP addresses. By default, the last occurrence is
10369 used. This is designed to work with the X-Forwarded-For header
Baptiste Assmannea3e73b2013-02-02 23:47:49 +010010370 and to automatically bind to the client's IP address as seen
Willy Tarreaubce70882009-09-07 11:51:47 +020010371 by previous proxy, typically Stunnel. In order to use another
10372 occurrence from the last one, please see the <occ> parameter
10373 below. When the header (or occurrence) is not found, no binding
10374 is performed so that the proxy's default IP address is used. Also
10375 keep in mind that the header name is case insensitive, as for any
10376 HTTP header.
10377
10378 <occ> is the occurrence number of a value to be used in a multi-value
10379 header. This is to be used in conjunction with "hdr_ip(<hdr>)",
Jamie Gloudonaaa21002012-08-25 00:18:33 -040010380 in order to specify which occurrence to use for the source IP
Willy Tarreaubce70882009-09-07 11:51:47 +020010381 address. Positive values indicate a position from the first
10382 occurrence, 1 being the first one. Negative values indicate
10383 positions relative to the last one, -1 being the last one. This
10384 is helpful for situations where an X-Forwarded-For header is set
10385 at the entry point of an infrastructure and must be used several
10386 proxy layers away. When this value is not specified, -1 is
10387 assumed. Passing a zero here disables the feature.
10388
Willy Tarreaud53f96b2009-02-04 18:46:54 +010010389 <name> is an optional interface name to which to bind to for outgoing
10390 traffic. On systems supporting this features (currently, only
10391 Linux), this allows one to bind all traffic to the server to
10392 this interface even if it is not the one the system would select
10393 based on routing tables. This should be used with extreme care.
10394 Note that using this option requires root privileges.
10395
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010396 The "source" keyword is useful in complex environments where a specific
10397 address only is allowed to connect to the servers. It may be needed when a
10398 private address must be used through a public gateway for instance, and it is
10399 known that the system cannot determine the adequate source address by itself.
10400
10401 An extension which is available on certain patched Linux kernels may be used
10402 through the "usesrc" optional keyword. It makes it possible to connect to the
10403 servers with an IP address which does not belong to the system itself. This
10404 is called "full transparent proxy mode". For this to work, the destination
10405 servers have to route their traffic back to this address through the machine
10406 running HAProxy, and IP forwarding must generally be enabled on this machine.
10407
10408 In this "full transparent proxy" mode, it is possible to force a specific IP
10409 address to be presented to the servers. This is not much used in fact. A more
10410 common use is to tell HAProxy to present the client's IP address. For this,
10411 there are two methods :
10412
10413 - present the client's IP and port addresses. This is the most transparent
10414 mode, but it can cause problems when IP connection tracking is enabled on
10415 the machine, because a same connection may be seen twice with different
10416 states. However, this solution presents the huge advantage of not
10417 limiting the system to the 64k outgoing address+port couples, because all
10418 of the client ranges may be used.
10419
10420 - present only the client's IP address and select a spare port. This
10421 solution is still quite elegant but slightly less transparent (downstream
10422 firewalls logs will not match upstream's). It also presents the downside
10423 of limiting the number of concurrent connections to the usual 64k ports.
10424 However, since the upstream and downstream ports are different, local IP
10425 connection tracking on the machine will not be upset by the reuse of the
10426 same session.
10427
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010428 This option sets the default source for all servers in the backend. It may
10429 also be specified in a "defaults" section. Finer source address specification
10430 is possible at the server level using the "source" server option. Refer to
Willy Tarreauc57f0e22009-05-10 13:12:33 +020010431 section 5 for more information.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010432
Baptiste Assmann91bd3372015-07-17 21:59:42 +020010433 In order to work, "usesrc" requires root privileges.
10434
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010435 Examples :
10436 backend private
10437 # Connect to the servers using our 192.168.1.200 source address
10438 source 192.168.1.200
10439
10440 backend transparent_ssl1
10441 # Connect to the SSL farm from the client's source address
10442 source 192.168.1.200 usesrc clientip
10443
10444 backend transparent_ssl2
10445 # Connect to the SSL farm from the client's source address and port
10446 # not recommended if IP conntrack is present on the local machine.
10447 source 192.168.1.200 usesrc client
10448
10449 backend transparent_ssl3
10450 # Connect to the SSL farm from the client's source address. It
10451 # is more conntrack-friendly.
10452 source 192.168.1.200 usesrc clientip
10453
10454 backend transparent_smtp
10455 # Connect to the SMTP farm from the client's source address/port
10456 # with Tproxy version 4.
10457 source 0.0.0.0 usesrc clientip
10458
Willy Tarreaubce70882009-09-07 11:51:47 +020010459 backend transparent_http
10460 # Connect to the servers using the client's IP as seen by previous
10461 # proxy.
10462 source 0.0.0.0 usesrc hdr_ip(x-forwarded-for,-1)
10463
Willy Tarreauc57f0e22009-05-10 13:12:33 +020010464 See also : the "source" server option in section 5, the Tproxy patches for
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010465 the Linux kernel on www.balabit.com, the "bind" keyword.
10466
Willy Tarreau844e3c52008-01-11 16:28:18 +010010467
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +090010468srvtcpka-cnt <count>
10469 Sets the maximum number of keepalive probes TCP should send before dropping
10470 the connection on the server side.
10471 May be used in sections : defaults | frontend | listen | backend
10472 yes | no | yes | yes
10473 Arguments :
10474 <count> is the maximum number of keepalive probes.
10475
10476 This keyword corresponds to the socket option TCP_KEEPCNT. If this keyword
10477 is not specified, system-wide TCP parameter (tcp_keepalive_probes) is used.
Willy Tarreau52543212020-07-09 05:58:51 +020010478 The availability of this setting depends on the operating system. It is
10479 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +090010480
10481 See also : "option srvtcpka", "srvtcpka-idle", "srvtcpka-intvl".
10482
10483
10484srvtcpka-idle <timeout>
10485 Sets the time the connection needs to remain idle before TCP starts sending
10486 keepalive probes, if enabled the sending of TCP keepalive packets on the
10487 server side.
10488 May be used in sections : defaults | frontend | listen | backend
10489 yes | no | yes | yes
10490 Arguments :
10491 <timeout> is the time the connection needs to remain idle before TCP starts
10492 sending keepalive probes. It is specified in seconds by default,
10493 but can be in any other unit if the number is suffixed by the
10494 unit, as explained at the top of this document.
10495
10496 This keyword corresponds to the socket option TCP_KEEPIDLE. If this keyword
10497 is not specified, system-wide TCP parameter (tcp_keepalive_time) is used.
Willy Tarreau52543212020-07-09 05:58:51 +020010498 The availability of this setting depends on the operating system. It is
10499 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +090010500
10501 See also : "option srvtcpka", "srvtcpka-cnt", "srvtcpka-intvl".
10502
10503
10504srvtcpka-intvl <timeout>
10505 Sets the time between individual keepalive probes on the server side.
10506 May be used in sections : defaults | frontend | listen | backend
10507 yes | no | yes | yes
10508 Arguments :
10509 <timeout> is the time between individual keepalive probes. It is specified
10510 in seconds by default, but can be in any other unit if the number
10511 is suffixed by the unit, as explained at the top of this
10512 document.
10513
10514 This keyword corresponds to the socket option TCP_KEEPINTVL. If this keyword
10515 is not specified, system-wide TCP parameter (tcp_keepalive_intvl) is used.
Willy Tarreau52543212020-07-09 05:58:51 +020010516 The availability of this setting depends on the operating system. It is
10517 known to work on Linux.
MIZUTA Takeshib24bc0d2020-07-09 11:13:20 +090010518
10519 See also : "option srvtcpka", "srvtcpka-cnt", "srvtcpka-idle".
10520
10521
Cyril Bonté66c327d2010-10-12 00:14:37 +020010522stats admin { if | unless } <cond>
10523 Enable statistics admin level if/unless a condition is matched
10524 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010525 no | yes | yes | yes
Cyril Bonté66c327d2010-10-12 00:14:37 +020010526
10527 This statement enables the statistics admin level if/unless a condition is
10528 matched.
10529
10530 The admin level allows to enable/disable servers from the web interface. By
10531 default, statistics page is read-only for security reasons.
10532
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010010533 Note : Consider not using this feature in multi-process mode (nbproc > 1)
10534 unless you know what you do : memory is not shared between the
Davor Ocelice9ed2812017-12-25 17:49:28 +010010535 processes, which can result in random behaviors.
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010010536
Cyril Bonté23b39d92011-02-10 22:54:44 +010010537 Currently, the POST request is limited to the buffer size minus the reserved
10538 buffer space, which means that if the list of servers is too long, the
10539 request won't be processed. It is recommended to alter few servers at a
10540 time.
Cyril Bonté66c327d2010-10-12 00:14:37 +020010541
10542 Example :
10543 # statistics admin level only for localhost
10544 backend stats_localhost
10545 stats enable
10546 stats admin if LOCALHOST
10547
10548 Example :
10549 # statistics admin level always enabled because of the authentication
10550 backend stats_auth
10551 stats enable
10552 stats auth admin:AdMiN123
10553 stats admin if TRUE
10554
10555 Example :
10556 # statistics admin level depends on the authenticated user
10557 userlist stats-auth
10558 group admin users admin
10559 user admin insecure-password AdMiN123
10560 group readonly users haproxy
10561 user haproxy insecure-password haproxy
10562
10563 backend stats_auth
10564 stats enable
10565 acl AUTH http_auth(stats-auth)
10566 acl AUTH_ADMIN http_auth_group(stats-auth) admin
10567 stats http-request auth unless AUTH
10568 stats admin if AUTH_ADMIN
10569
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010010570 See also : "stats enable", "stats auth", "stats http-request", "nbproc",
10571 "bind-process", section 3.4 about userlists and section 7 about
10572 ACL usage.
Cyril Bonté66c327d2010-10-12 00:14:37 +020010573
10574
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010575stats auth <user>:<passwd>
10576 Enable statistics with authentication and grant access to an account
10577 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010578 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010579 Arguments :
10580 <user> is a user name to grant access to
10581
10582 <passwd> is the cleartext password associated to this user
10583
10584 This statement enables statistics with default settings, and restricts access
10585 to declared users only. It may be repeated as many times as necessary to
10586 allow as many users as desired. When a user tries to access the statistics
10587 without a valid account, a "401 Forbidden" response will be returned so that
10588 the browser asks the user to provide a valid user and password. The real
10589 which will be returned to the browser is configurable using "stats realm".
10590
10591 Since the authentication method is HTTP Basic Authentication, the passwords
10592 circulate in cleartext on the network. Thus, it was decided that the
10593 configuration file would also use cleartext passwords to remind the users
Willy Tarreau3c92c5f2011-08-28 09:45:47 +020010594 that those ones should not be sensitive and not shared with any other account.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010595
10596 It is also possible to reduce the scope of the proxies which appear in the
10597 report using "stats scope".
10598
10599 Though this statement alone is enough to enable statistics reporting, it is
10600 recommended to set all other settings in order to avoid relying on default
10601 unobvious parameters.
10602
10603 Example :
10604 # public access (limited to this backend only)
10605 backend public_www
10606 server srv1 192.168.0.1:80
10607 stats enable
10608 stats hide-version
10609 stats scope .
10610 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010611 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010612 stats auth admin1:AdMiN123
10613 stats auth admin2:AdMiN321
10614
10615 # internal monitoring access (unlimited)
10616 backend private_monitoring
10617 stats enable
10618 stats uri /admin?stats
10619 stats refresh 5s
10620
10621 See also : "stats enable", "stats realm", "stats scope", "stats uri"
10622
10623
10624stats enable
10625 Enable statistics reporting with default settings
10626 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010627 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010628 Arguments : none
10629
10630 This statement enables statistics reporting with default settings defined
10631 at build time. Unless stated otherwise, these settings are used :
10632 - stats uri : /haproxy?stats
10633 - stats realm : "HAProxy Statistics"
10634 - stats auth : no authentication
10635 - stats scope : no restriction
10636
10637 Though this statement alone is enough to enable statistics reporting, it is
10638 recommended to set all other settings in order to avoid relying on default
10639 unobvious parameters.
10640
10641 Example :
10642 # public access (limited to this backend only)
10643 backend public_www
10644 server srv1 192.168.0.1:80
10645 stats enable
10646 stats hide-version
10647 stats scope .
10648 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010649 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010650 stats auth admin1:AdMiN123
10651 stats auth admin2:AdMiN321
10652
10653 # internal monitoring access (unlimited)
10654 backend private_monitoring
10655 stats enable
10656 stats uri /admin?stats
10657 stats refresh 5s
10658
10659 See also : "stats auth", "stats realm", "stats uri"
10660
10661
Willy Tarreaud63335a2010-02-26 12:56:52 +010010662stats hide-version
10663 Enable statistics and hide HAProxy version reporting
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010664 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010665 yes | yes | yes | yes
Willy Tarreaud63335a2010-02-26 12:56:52 +010010666 Arguments : none
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010667
Willy Tarreaud63335a2010-02-26 12:56:52 +010010668 By default, the stats page reports some useful status information along with
10669 the statistics. Among them is HAProxy's version. However, it is generally
10670 considered dangerous to report precise version to anyone, as it can help them
10671 target known weaknesses with specific attacks. The "stats hide-version"
10672 statement removes the version from the statistics report. This is recommended
10673 for public sites or any site with a weak login/password.
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010674
Krzysztof Piotr Oledzki48cb2ae2009-10-02 22:51:14 +020010675 Though this statement alone is enough to enable statistics reporting, it is
10676 recommended to set all other settings in order to avoid relying on default
10677 unobvious parameters.
10678
Willy Tarreaud63335a2010-02-26 12:56:52 +010010679 Example :
10680 # public access (limited to this backend only)
10681 backend public_www
10682 server srv1 192.168.0.1:80
Krzysztof Piotr Oledzki48cb2ae2009-10-02 22:51:14 +020010683 stats enable
Willy Tarreaud63335a2010-02-26 12:56:52 +010010684 stats hide-version
10685 stats scope .
10686 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010687 stats realm HAProxy\ Statistics
Willy Tarreaud63335a2010-02-26 12:56:52 +010010688 stats auth admin1:AdMiN123
10689 stats auth admin2:AdMiN321
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010690
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010691 # internal monitoring access (unlimited)
10692 backend private_monitoring
10693 stats enable
Willy Tarreaud63335a2010-02-26 12:56:52 +010010694 stats uri /admin?stats
10695 stats refresh 5s
Krzysztof Piotr Oledzki15514c22010-01-04 16:03:09 +010010696
Willy Tarreaud63335a2010-02-26 12:56:52 +010010697 See also : "stats auth", "stats enable", "stats realm", "stats uri"
Willy Tarreau1d45b7c2009-08-16 10:29:18 +020010698
Willy Tarreau983e01e2010-01-11 18:42:06 +010010699
Cyril Bonté2be1b3f2010-09-30 23:46:30 +020010700stats http-request { allow | deny | auth [realm <realm>] }
10701 [ { if | unless } <condition> ]
10702 Access control for statistics
10703
10704 May be used in sections: defaults | frontend | listen | backend
10705 no | no | yes | yes
10706
10707 As "http-request", these set of options allow to fine control access to
10708 statistics. Each option may be followed by if/unless and acl.
10709 First option with matched condition (or option without condition) is final.
10710 For "deny" a 403 error will be returned, for "allow" normal processing is
10711 performed, for "auth" a 401/407 error code is returned so the client
10712 should be asked to enter a username and password.
10713
10714 There is no fixed limit to the number of http-request statements per
10715 instance.
10716
10717 See also : "http-request", section 3.4 about userlists and section 7
10718 about ACL usage.
10719
10720
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010721stats realm <realm>
10722 Enable statistics and set authentication realm
10723 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010724 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010725 Arguments :
10726 <realm> is the name of the HTTP Basic Authentication realm reported to
10727 the browser. The browser uses it to display it in the pop-up
10728 inviting the user to enter a valid username and password.
10729
10730 The realm is read as a single word, so any spaces in it should be escaped
10731 using a backslash ('\').
10732
10733 This statement is useful only in conjunction with "stats auth" since it is
10734 only related to authentication.
10735
10736 Though this statement alone is enough to enable statistics reporting, it is
10737 recommended to set all other settings in order to avoid relying on default
10738 unobvious parameters.
10739
10740 Example :
10741 # public access (limited to this backend only)
10742 backend public_www
10743 server srv1 192.168.0.1:80
10744 stats enable
10745 stats hide-version
10746 stats scope .
10747 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010748 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010749 stats auth admin1:AdMiN123
10750 stats auth admin2:AdMiN321
10751
10752 # internal monitoring access (unlimited)
10753 backend private_monitoring
10754 stats enable
10755 stats uri /admin?stats
10756 stats refresh 5s
10757
10758 See also : "stats auth", "stats enable", "stats uri"
10759
10760
10761stats refresh <delay>
10762 Enable statistics with automatic refresh
10763 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010764 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010765 Arguments :
10766 <delay> is the suggested refresh delay, specified in seconds, which will
10767 be returned to the browser consulting the report page. While the
10768 browser is free to apply any delay, it will generally respect it
10769 and refresh the page this every seconds. The refresh interval may
10770 be specified in any other non-default time unit, by suffixing the
10771 unit after the value, as explained at the top of this document.
10772
10773 This statement is useful on monitoring displays with a permanent page
10774 reporting the load balancer's activity. When set, the HTML report page will
10775 include a link "refresh"/"stop refresh" so that the user can select whether
Jackie Tapia749f74c2020-07-22 18:59:40 -050010776 they want automatic refresh of the page or not.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010777
10778 Though this statement alone is enough to enable statistics reporting, it is
10779 recommended to set all other settings in order to avoid relying on default
10780 unobvious parameters.
10781
10782 Example :
10783 # public access (limited to this backend only)
10784 backend public_www
10785 server srv1 192.168.0.1:80
10786 stats enable
10787 stats hide-version
10788 stats scope .
10789 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010790 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010791 stats auth admin1:AdMiN123
10792 stats auth admin2:AdMiN321
10793
10794 # internal monitoring access (unlimited)
10795 backend private_monitoring
10796 stats enable
10797 stats uri /admin?stats
10798 stats refresh 5s
10799
10800 See also : "stats auth", "stats enable", "stats realm", "stats uri"
10801
10802
10803stats scope { <name> | "." }
10804 Enable statistics and limit access scope
10805 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010806 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010807 Arguments :
10808 <name> is the name of a listen, frontend or backend section to be
10809 reported. The special name "." (a single dot) designates the
10810 section in which the statement appears.
10811
10812 When this statement is specified, only the sections enumerated with this
10813 statement will appear in the report. All other ones will be hidden. This
10814 statement may appear as many times as needed if multiple sections need to be
10815 reported. Please note that the name checking is performed as simple string
10816 comparisons, and that it is never checked that a give section name really
10817 exists.
10818
10819 Though this statement alone is enough to enable statistics reporting, it is
10820 recommended to set all other settings in order to avoid relying on default
10821 unobvious parameters.
10822
10823 Example :
10824 # public access (limited to this backend only)
10825 backend public_www
10826 server srv1 192.168.0.1:80
10827 stats enable
10828 stats hide-version
10829 stats scope .
10830 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010831 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010832 stats auth admin1:AdMiN123
10833 stats auth admin2:AdMiN321
10834
10835 # internal monitoring access (unlimited)
10836 backend private_monitoring
10837 stats enable
10838 stats uri /admin?stats
10839 stats refresh 5s
10840
10841 See also : "stats auth", "stats enable", "stats realm", "stats uri"
10842
Willy Tarreaud63335a2010-02-26 12:56:52 +010010843
Willy Tarreauc9705a12010-07-27 20:05:50 +020010844stats show-desc [ <desc> ]
Willy Tarreaud63335a2010-02-26 12:56:52 +010010845 Enable reporting of a description on the statistics page.
10846 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010847 yes | yes | yes | yes
Willy Tarreaud63335a2010-02-26 12:56:52 +010010848
Willy Tarreauc9705a12010-07-27 20:05:50 +020010849 <desc> is an optional description to be reported. If unspecified, the
Willy Tarreaud63335a2010-02-26 12:56:52 +010010850 description from global section is automatically used instead.
10851
10852 This statement is useful for users that offer shared services to their
10853 customers, where node or description should be different for each customer.
10854
10855 Though this statement alone is enough to enable statistics reporting, it is
10856 recommended to set all other settings in order to avoid relying on default
Davor Ocelice9ed2812017-12-25 17:49:28 +010010857 unobvious parameters. By default description is not shown.
Willy Tarreaud63335a2010-02-26 12:56:52 +010010858
10859 Example :
10860 # internal monitoring access (unlimited)
10861 backend private_monitoring
10862 stats enable
10863 stats show-desc Master node for Europe, Asia, Africa
10864 stats uri /admin?stats
10865 stats refresh 5s
10866
10867 See also: "show-node", "stats enable", "stats uri" and "description" in
10868 global section.
10869
10870
10871stats show-legends
Willy Tarreaued2119c2014-04-24 22:10:39 +020010872 Enable reporting additional information on the statistics page
10873 May be used in sections : defaults | frontend | listen | backend
10874 yes | yes | yes | yes
10875 Arguments : none
10876
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030010877 Enable reporting additional information on the statistics page :
Willy Tarreaud63335a2010-02-26 12:56:52 +010010878 - cap: capabilities (proxy)
10879 - mode: one of tcp, http or health (proxy)
10880 - id: SNMP ID (proxy, socket, server)
10881 - IP (socket, server)
10882 - cookie (backend, server)
10883
10884 Though this statement alone is enough to enable statistics reporting, it is
10885 recommended to set all other settings in order to avoid relying on default
Davor Ocelice9ed2812017-12-25 17:49:28 +010010886 unobvious parameters. Default behavior is not to show this information.
Willy Tarreaud63335a2010-02-26 12:56:52 +010010887
10888 See also: "stats enable", "stats uri".
10889
10890
Amaury Denoyelle0b70a8a2020-10-05 11:49:45 +020010891stats show-modules
10892 Enable display of extra statistics module on the statistics page
10893 May be used in sections : defaults | frontend | listen | backend
10894 yes | yes | yes | yes
10895 Arguments : none
10896
10897 New columns are added at the end of the line containing the extra statistics
10898 values as a tooltip.
10899
10900 Though this statement alone is enough to enable statistics reporting, it is
10901 recommended to set all other settings in order to avoid relying on default
10902 unobvious parameters. Default behavior is not to show this information.
10903
10904 See also: "stats enable", "stats uri".
10905
10906
Willy Tarreaud63335a2010-02-26 12:56:52 +010010907stats show-node [ <name> ]
10908 Enable reporting of a host name on the statistics page.
10909 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010910 yes | yes | yes | yes
Willy Tarreaud63335a2010-02-26 12:56:52 +010010911 Arguments:
10912 <name> is an optional name to be reported. If unspecified, the
10913 node name from global section is automatically used instead.
10914
10915 This statement is useful for users that offer shared services to their
10916 customers, where node or description might be different on a stats page
Davor Ocelice9ed2812017-12-25 17:49:28 +010010917 provided for each customer. Default behavior is not to show host name.
Willy Tarreaud63335a2010-02-26 12:56:52 +010010918
10919 Though this statement alone is enough to enable statistics reporting, it is
10920 recommended to set all other settings in order to avoid relying on default
10921 unobvious parameters.
10922
10923 Example:
10924 # internal monitoring access (unlimited)
10925 backend private_monitoring
10926 stats enable
10927 stats show-node Europe-1
10928 stats uri /admin?stats
10929 stats refresh 5s
10930
10931 See also: "show-desc", "stats enable", "stats uri", and "node" in global
10932 section.
10933
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010934
10935stats uri <prefix>
10936 Enable statistics and define the URI prefix to access them
10937 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaued2119c2014-04-24 22:10:39 +020010938 yes | yes | yes | yes
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010939 Arguments :
10940 <prefix> is the prefix of any URI which will be redirected to stats. This
10941 prefix may contain a question mark ('?') to indicate part of a
10942 query string.
10943
10944 The statistics URI is intercepted on the relayed traffic, so it appears as a
10945 page within the normal application. It is strongly advised to ensure that the
10946 selected URI will never appear in the application, otherwise it will never be
10947 possible to reach it in the application.
10948
Daniel Corbett9f0843f2021-05-08 10:50:37 -040010949 The default URI compiled in HAProxy is "/haproxy?stats", but this may be
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010010950 changed at build time, so it's better to always explicitly specify it here.
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010951 It is generally a good idea to include a question mark in the URI so that
10952 intermediate proxies refrain from caching the results. Also, since any string
10953 beginning with the prefix will be accepted as a stats request, the question
10954 mark helps ensuring that no valid URI will begin with the same words.
10955
10956 It is sometimes very convenient to use "/" as the URI prefix, and put that
10957 statement in a "listen" instance of its own. That makes it easy to dedicate
10958 an address or a port to statistics only.
10959
10960 Though this statement alone is enough to enable statistics reporting, it is
10961 recommended to set all other settings in order to avoid relying on default
10962 unobvious parameters.
10963
10964 Example :
10965 # public access (limited to this backend only)
10966 backend public_www
10967 server srv1 192.168.0.1:80
10968 stats enable
10969 stats hide-version
10970 stats scope .
10971 stats uri /admin?stats
Davor Ocelice9ed2812017-12-25 17:49:28 +010010972 stats realm HAProxy\ Statistics
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010973 stats auth admin1:AdMiN123
10974 stats auth admin2:AdMiN321
10975
10976 # internal monitoring access (unlimited)
10977 backend private_monitoring
10978 stats enable
10979 stats uri /admin?stats
10980 stats refresh 5s
10981
10982 See also : "stats auth", "stats enable", "stats realm"
10983
10984
Willy Tarreaud63335a2010-02-26 12:56:52 +010010985stick match <pattern> [table <table>] [{if | unless} <cond>]
10986 Define a request pattern matching condition to stick a user to a server
Willy Tarreaueabeafa2008-01-16 16:17:06 +010010987 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaud63335a2010-02-26 12:56:52 +010010988 no | no | yes | yes
Willy Tarreaub937b7e2010-01-12 15:27:54 +010010989
10990 Arguments :
Willy Tarreaube722a22014-06-13 16:31:59 +020010991 <pattern> is a sample expression rule as described in section 7.3. It
Willy Tarreaub937b7e2010-01-12 15:27:54 +010010992 describes what elements of the incoming request or connection
Davor Ocelice9ed2812017-12-25 17:49:28 +010010993 will be analyzed in the hope to find a matching entry in a
Willy Tarreaub937b7e2010-01-12 15:27:54 +010010994 stickiness table. This rule is mandatory.
10995
10996 <table> is an optional stickiness table name. If unspecified, the same
10997 backend's table is used. A stickiness table is declared using
10998 the "stick-table" statement.
10999
11000 <cond> is an optional matching condition. It makes it possible to match
11001 on a certain criterion only when other conditions are met (or
11002 not met). For instance, it could be used to match on a source IP
11003 address except when a request passes through a known proxy, in
11004 which case we'd match on a header containing that IP address.
11005
11006 Some protocols or applications require complex stickiness rules and cannot
11007 always simply rely on cookies nor hashing. The "stick match" statement
11008 describes a rule to extract the stickiness criterion from an incoming request
11009 or connection. See section 7 for a complete list of possible patterns and
11010 transformation rules.
11011
11012 The table has to be declared using the "stick-table" statement. It must be of
11013 a type compatible with the pattern. By default it is the one which is present
11014 in the same backend. It is possible to share a table with other backends by
11015 referencing it using the "table" keyword. If another table is referenced,
11016 the server's ID inside the backends are used. By default, all server IDs
11017 start at 1 in each backend, so the server ordering is enough. But in case of
11018 doubt, it is highly recommended to force server IDs using their "id" setting.
11019
11020 It is possible to restrict the conditions where a "stick match" statement
11021 will apply, using "if" or "unless" followed by a condition. See section 7 for
11022 ACL based conditions.
11023
11024 There is no limit on the number of "stick match" statements. The first that
11025 applies and matches will cause the request to be directed to the same server
11026 as was used for the request which created the entry. That way, multiple
11027 matches can be used as fallbacks.
11028
11029 The stick rules are checked after the persistence cookies, so they will not
11030 affect stickiness if a cookie has already been used to select a server. That
11031 way, it becomes very easy to insert cookies and match on IP addresses in
11032 order to maintain stickiness between HTTP and HTTPS.
11033
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011034 Note : Consider not using this feature in multi-process mode (nbproc > 1)
11035 unless you know what you do : memory is not shared between the
Davor Ocelice9ed2812017-12-25 17:49:28 +010011036 processes, which can result in random behaviors.
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011037
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011038 Example :
11039 # forward SMTP users to the same server they just used for POP in the
11040 # last 30 minutes
11041 backend pop
11042 mode tcp
11043 balance roundrobin
11044 stick store-request src
11045 stick-table type ip size 200k expire 30m
11046 server s1 192.168.1.1:110
11047 server s2 192.168.1.1:110
11048
11049 backend smtp
11050 mode tcp
11051 balance roundrobin
11052 stick match src table pop
11053 server s1 192.168.1.1:25
11054 server s2 192.168.1.1:25
11055
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011056 See also : "stick-table", "stick on", "nbproc", "bind-process" and section 7
Willy Tarreaube722a22014-06-13 16:31:59 +020011057 about ACLs and samples fetching.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011058
11059
11060stick on <pattern> [table <table>] [{if | unless} <condition>]
11061 Define a request pattern to associate a user to a server
11062 May be used in sections : defaults | frontend | listen | backend
11063 no | no | yes | yes
11064
11065 Note : This form is exactly equivalent to "stick match" followed by
11066 "stick store-request", all with the same arguments. Please refer
11067 to both keywords for details. It is only provided as a convenience
11068 for writing more maintainable configurations.
11069
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011070 Note : Consider not using this feature in multi-process mode (nbproc > 1)
11071 unless you know what you do : memory is not shared between the
Davor Ocelice9ed2812017-12-25 17:49:28 +010011072 processes, which can result in random behaviors.
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011073
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011074 Examples :
11075 # The following form ...
Willy Tarreauec579d82010-02-26 19:15:04 +010011076 stick on src table pop if !localhost
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011077
11078 # ...is strictly equivalent to this one :
11079 stick match src table pop if !localhost
11080 stick store-request src table pop if !localhost
11081
11082
11083 # Use cookie persistence for HTTP, and stick on source address for HTTPS as
11084 # well as HTTP without cookie. Share the same table between both accesses.
11085 backend http
11086 mode http
11087 balance roundrobin
11088 stick on src table https
11089 cookie SRV insert indirect nocache
11090 server s1 192.168.1.1:80 cookie s1
11091 server s2 192.168.1.1:80 cookie s2
11092
11093 backend https
11094 mode tcp
11095 balance roundrobin
11096 stick-table type ip size 200k expire 30m
11097 stick on src
11098 server s1 192.168.1.1:443
11099 server s2 192.168.1.1:443
11100
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011101 See also : "stick match", "stick store-request", "nbproc" and "bind-process".
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011102
11103
11104stick store-request <pattern> [table <table>] [{if | unless} <condition>]
11105 Define a request pattern used to create an entry in a stickiness table
11106 May be used in sections : defaults | frontend | listen | backend
11107 no | no | yes | yes
11108
11109 Arguments :
Willy Tarreaube722a22014-06-13 16:31:59 +020011110 <pattern> is a sample expression rule as described in section 7.3. It
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011111 describes what elements of the incoming request or connection
Davor Ocelice9ed2812017-12-25 17:49:28 +010011112 will be analyzed, extracted and stored in the table once a
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011113 server is selected.
11114
11115 <table> is an optional stickiness table name. If unspecified, the same
11116 backend's table is used. A stickiness table is declared using
11117 the "stick-table" statement.
11118
11119 <cond> is an optional storage condition. It makes it possible to store
11120 certain criteria only when some conditions are met (or not met).
11121 For instance, it could be used to store the source IP address
11122 except when the request passes through a known proxy, in which
11123 case we'd store a converted form of a header containing that IP
11124 address.
11125
11126 Some protocols or applications require complex stickiness rules and cannot
11127 always simply rely on cookies nor hashing. The "stick store-request" statement
11128 describes a rule to decide what to extract from the request and when to do
11129 it, in order to store it into a stickiness table for further requests to
11130 match it using the "stick match" statement. Obviously the extracted part must
11131 make sense and have a chance to be matched in a further request. Storing a
11132 client's IP address for instance often makes sense. Storing an ID found in a
11133 URL parameter also makes sense. Storing a source port will almost never make
11134 any sense because it will be randomly matched. See section 7 for a complete
11135 list of possible patterns and transformation rules.
11136
11137 The table has to be declared using the "stick-table" statement. It must be of
11138 a type compatible with the pattern. By default it is the one which is present
11139 in the same backend. It is possible to share a table with other backends by
11140 referencing it using the "table" keyword. If another table is referenced,
11141 the server's ID inside the backends are used. By default, all server IDs
11142 start at 1 in each backend, so the server ordering is enough. But in case of
11143 doubt, it is highly recommended to force server IDs using their "id" setting.
11144
11145 It is possible to restrict the conditions where a "stick store-request"
11146 statement will apply, using "if" or "unless" followed by a condition. This
11147 condition will be evaluated while parsing the request, so any criteria can be
11148 used. See section 7 for ACL based conditions.
11149
11150 There is no limit on the number of "stick store-request" statements, but
11151 there is a limit of 8 simultaneous stores per request or response. This
11152 makes it possible to store up to 8 criteria, all extracted from either the
11153 request or the response, regardless of the number of rules. Only the 8 first
11154 ones which match will be kept. Using this, it is possible to feed multiple
11155 tables at once in the hope to increase the chance to recognize a user on
Willy Tarreau9667a802013-12-09 12:52:13 +010011156 another protocol or access method. Using multiple store-request rules with
11157 the same table is possible and may be used to find the best criterion to rely
11158 on, by arranging the rules by decreasing preference order. Only the first
11159 extracted criterion for a given table will be stored. All subsequent store-
11160 request rules referencing the same table will be skipped and their ACLs will
11161 not be evaluated.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011162
11163 The "store-request" rules are evaluated once the server connection has been
11164 established, so that the table will contain the real server that processed
11165 the request.
11166
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011167 Note : Consider not using this feature in multi-process mode (nbproc > 1)
11168 unless you know what you do : memory is not shared between the
Davor Ocelice9ed2812017-12-25 17:49:28 +010011169 processes, which can result in random behaviors.
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011170
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011171 Example :
11172 # forward SMTP users to the same server they just used for POP in the
11173 # last 30 minutes
11174 backend pop
11175 mode tcp
11176 balance roundrobin
11177 stick store-request src
11178 stick-table type ip size 200k expire 30m
11179 server s1 192.168.1.1:110
11180 server s2 192.168.1.1:110
11181
11182 backend smtp
11183 mode tcp
11184 balance roundrobin
11185 stick match src table pop
11186 server s1 192.168.1.1:25
11187 server s2 192.168.1.1:25
11188
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011189 See also : "stick-table", "stick on", "nbproc", "bind-process" and section 7
Willy Tarreaube722a22014-06-13 16:31:59 +020011190 about ACLs and sample fetching.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011191
11192
Emeric Brun7c6b82e2010-09-24 16:34:28 +020011193stick-table type {ip | integer | string [len <length>] | binary [len <length>]}
Thayne McCombs92149f92020-11-20 01:28:26 -070011194 size <size> [expire <expire>] [nopurge] [peers <peersect>] [srvkey <srvkey>]
Emeric Brunf099e792010-09-27 12:05:28 +020011195 [store <data_type>]*
Godbach64cef792013-12-04 16:08:22 +080011196 Configure the stickiness table for the current section
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011197 May be used in sections : defaults | frontend | listen | backend
Willy Tarreauc00cdc22010-06-06 16:48:26 +020011198 no | yes | yes | yes
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011199
11200 Arguments :
11201 ip a table declared with "type ip" will only store IPv4 addresses.
11202 This form is very compact (about 50 bytes per entry) and allows
11203 very fast entry lookup and stores with almost no overhead. This
11204 is mainly used to store client source IP addresses.
11205
David du Colombier9a6d3c92011-03-17 10:40:24 +010011206 ipv6 a table declared with "type ipv6" will only store IPv6 addresses.
11207 This form is very compact (about 60 bytes per entry) and allows
11208 very fast entry lookup and stores with almost no overhead. This
11209 is mainly used to store client source IP addresses.
11210
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011211 integer a table declared with "type integer" will store 32bit integers
11212 which can represent a client identifier found in a request for
11213 instance.
11214
11215 string a table declared with "type string" will store substrings of up
11216 to <len> characters. If the string provided by the pattern
11217 extractor is larger than <len>, it will be truncated before
11218 being stored. During matching, at most <len> characters will be
11219 compared between the string in the table and the extracted
11220 pattern. When not specified, the string is automatically limited
Emeric Brun7c6b82e2010-09-24 16:34:28 +020011221 to 32 characters.
11222
11223 binary a table declared with "type binary" will store binary blocks
11224 of <len> bytes. If the block provided by the pattern
11225 extractor is larger than <len>, it will be truncated before
Willy Tarreaube722a22014-06-13 16:31:59 +020011226 being stored. If the block provided by the sample expression
Emeric Brun7c6b82e2010-09-24 16:34:28 +020011227 is shorter than <len>, it will be padded by 0. When not
11228 specified, the block is automatically limited to 32 bytes.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011229
11230 <length> is the maximum number of characters that will be stored in a
Emeric Brun7c6b82e2010-09-24 16:34:28 +020011231 "string" type table (See type "string" above). Or the number
11232 of bytes of the block in "binary" type table. Be careful when
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011233 changing this parameter as memory usage will proportionally
11234 increase.
11235
11236 <size> is the maximum number of entries that can fit in the table. This
Cyril Bonté78caf842010-03-10 22:41:43 +010011237 value directly impacts memory usage. Count approximately
11238 50 bytes per entry, plus the size of a string if any. The size
11239 supports suffixes "k", "m", "g" for 2^10, 2^20 and 2^30 factors.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011240
11241 [nopurge] indicates that we refuse to purge older entries when the table
Daniel Corbett9f0843f2021-05-08 10:50:37 -040011242 is full. When not specified and the table is full when HAProxy
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011243 wants to store an entry in it, it will flush a few of the oldest
11244 entries in order to release some space for the new ones. This is
Davor Ocelice9ed2812017-12-25 17:49:28 +010011245 most often the desired behavior. In some specific cases, it
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011246 be desirable to refuse new entries instead of purging the older
11247 ones. That may be the case when the amount of data to store is
11248 far above the hardware limits and we prefer not to offer access
11249 to new clients than to reject the ones already connected. When
11250 using this parameter, be sure to properly set the "expire"
11251 parameter (see below).
11252
Emeric Brunf099e792010-09-27 12:05:28 +020011253 <peersect> is the name of the peers section to use for replication. Entries
11254 which associate keys to server IDs are kept synchronized with
11255 the remote peers declared in this section. All entries are also
11256 automatically learned from the local peer (old process) during a
11257 soft restart.
11258
Willy Tarreau1abc6732015-05-01 19:21:02 +020011259 NOTE : each peers section may be referenced only by tables
11260 belonging to the same unique process.
Cyril Bonté02ff8ef2010-12-14 22:48:49 +010011261
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011262 <expire> defines the maximum duration of an entry in the table since it
11263 was last created, refreshed or matched. The expiration delay is
11264 defined using the standard time format, similarly as the various
11265 timeouts. The maximum duration is slightly above 24 days. See
Willy Tarreau4b103022021-02-12 17:59:10 +010011266 section 2.5 for more information. If this delay is not specified,
Cyril Bontédc4d9032012-04-08 21:57:39 +020011267 the session won't automatically expire, but older entries will
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011268 be removed once full. Be sure not to use the "nopurge" parameter
11269 if not expiration delay is specified.
11270
Thayne McCombs92149f92020-11-20 01:28:26 -070011271 <srvkey> specifies how each server is identified for the purposes of the
11272 stick table. The valid values are "name" and "addr". If "name" is
11273 given, then <name> argument for the server (may be generated by
11274 a template). If "addr" is given, then the server is identified
11275 by its current network address, including the port. "addr" is
11276 especially useful if you are using service discovery to generate
11277 the addresses for servers with peered stick-tables and want
11278 to consistently use the same host across peers for a stickiness
11279 token.
11280
Willy Tarreau08d5f982010-06-06 13:34:54 +020011281 <data_type> is used to store additional information in the stick-table. This
11282 may be used by ACLs in order to control various criteria related
11283 to the activity of the client matching the stick-table. For each
11284 item specified here, the size of each entry will be inflated so
Willy Tarreauc9705a12010-07-27 20:05:50 +020011285 that the additional data can fit. Several data types may be
11286 stored with an entry. Multiple data types may be specified after
11287 the "store" keyword, as a comma-separated list. Alternatively,
11288 it is possible to repeat the "store" keyword followed by one or
11289 several data types. Except for the "server_id" type which is
11290 automatically detected and enabled, all data types must be
11291 explicitly declared to be stored. If an ACL references a data
11292 type which is not stored, the ACL will simply not match. Some
11293 data types require an argument which must be passed just after
11294 the type between parenthesis. See below for the supported data
11295 types and their arguments.
11296
11297 The data types that can be stored with an entry are the following :
11298 - server_id : this is an integer which holds the numeric ID of the server a
11299 request was assigned to. It is used by the "stick match", "stick store",
11300 and "stick on" rules. It is automatically enabled when referenced.
11301
11302 - gpc0 : first General Purpose Counter. It is a positive 32-bit integer
11303 integer which may be used for anything. Most of the time it will be used
11304 to put a special tag on some entries, for instance to note that a
Davor Ocelice9ed2812017-12-25 17:49:28 +010011305 specific behavior was detected and must be known for future matches.
Willy Tarreauc9705a12010-07-27 20:05:50 +020011306
Willy Tarreauba2ffd12013-05-29 15:54:14 +020011307 - gpc0_rate(<period>) : increment rate of the first General Purpose Counter
11308 over a period. It is a positive 32-bit integer integer which may be used
11309 for anything. Just like <gpc0>, it counts events, but instead of keeping
Davor Ocelice9ed2812017-12-25 17:49:28 +010011310 a cumulative number, it maintains the rate at which the counter is
Willy Tarreauba2ffd12013-05-29 15:54:14 +020011311 incremented. Most of the time it will be used to measure the frequency of
Davor Ocelice9ed2812017-12-25 17:49:28 +010011312 occurrence of certain events (e.g. requests to a specific URL).
Willy Tarreauba2ffd12013-05-29 15:54:14 +020011313
Frédéric Lécaille6778b272018-01-29 15:22:53 +010011314 - gpc1 : second General Purpose Counter. It is a positive 32-bit integer
11315 integer which may be used for anything. Most of the time it will be used
11316 to put a special tag on some entries, for instance to note that a
11317 specific behavior was detected and must be known for future matches.
11318
11319 - gpc1_rate(<period>) : increment rate of the second General Purpose Counter
11320 over a period. It is a positive 32-bit integer integer which may be used
11321 for anything. Just like <gpc1>, it counts events, but instead of keeping
11322 a cumulative number, it maintains the rate at which the counter is
11323 incremented. Most of the time it will be used to measure the frequency of
11324 occurrence of certain events (e.g. requests to a specific URL).
11325
Emeric Bruna5d15312021-07-01 18:34:48 +020011326 - gpt0 : first General Purpose Tag. It is a positive 32-bit integer
11327 integer which may be used for anything. Most of the time it will be used
11328 to put a special tag on some entries, for instance to note that a
11329 specific behavior was detected and must be known for future matches
11330
Willy Tarreauc9705a12010-07-27 20:05:50 +020011331 - conn_cnt : Connection Count. It is a positive 32-bit integer which counts
11332 the absolute number of connections received from clients which matched
11333 this entry. It does not mean the connections were accepted, just that
11334 they were received.
11335
11336 - conn_cur : Current Connections. It is a positive 32-bit integer which
11337 stores the concurrent connection counts for the entry. It is incremented
11338 once an incoming connection matches the entry, and decremented once the
11339 connection leaves. That way it is possible to know at any time the exact
11340 number of concurrent connections for an entry.
11341
11342 - conn_rate(<period>) : frequency counter (takes 12 bytes). It takes an
11343 integer parameter <period> which indicates in milliseconds the length
11344 of the period over which the average is measured. It reports the average
11345 incoming connection rate over that period, in connections per period. The
11346 result is an integer which can be matched using ACLs.
11347
11348 - sess_cnt : Session Count. It is a positive 32-bit integer which counts
11349 the absolute number of sessions received from clients which matched this
11350 entry. A session is a connection that was accepted by the layer 4 rules.
11351
11352 - sess_rate(<period>) : frequency counter (takes 12 bytes). It takes an
11353 integer parameter <period> which indicates in milliseconds the length
11354 of the period over which the average is measured. It reports the average
11355 incoming session rate over that period, in sessions per period. The
11356 result is an integer which can be matched using ACLs.
11357
11358 - http_req_cnt : HTTP request Count. It is a positive 32-bit integer which
11359 counts the absolute number of HTTP requests received from clients which
11360 matched this entry. It does not matter whether they are valid requests or
11361 not. Note that this is different from sessions when keep-alive is used on
11362 the client side.
11363
11364 - http_req_rate(<period>) : frequency counter (takes 12 bytes). It takes an
11365 integer parameter <period> which indicates in milliseconds the length
11366 of the period over which the average is measured. It reports the average
11367 HTTP request rate over that period, in requests per period. The result is
11368 an integer which can be matched using ACLs. It does not matter whether
11369 they are valid requests or not. Note that this is different from sessions
11370 when keep-alive is used on the client side.
11371
11372 - http_err_cnt : HTTP Error Count. It is a positive 32-bit integer which
11373 counts the absolute number of HTTP requests errors induced by clients
11374 which matched this entry. Errors are counted on invalid and truncated
11375 requests, as well as on denied or tarpitted requests, and on failed
11376 authentications. If the server responds with 4xx, then the request is
11377 also counted as an error since it's an error triggered by the client
Davor Ocelice9ed2812017-12-25 17:49:28 +010011378 (e.g. vulnerability scan).
Willy Tarreauc9705a12010-07-27 20:05:50 +020011379
11380 - http_err_rate(<period>) : frequency counter (takes 12 bytes). It takes an
11381 integer parameter <period> which indicates in milliseconds the length
11382 of the period over which the average is measured. It reports the average
11383 HTTP request error rate over that period, in requests per period (see
11384 http_err_cnt above for what is accounted as an error). The result is an
11385 integer which can be matched using ACLs.
11386
Willy Tarreau826f3ab2021-02-10 12:07:15 +010011387 - http_fail_cnt : HTTP Failure Count. It is a positive 32-bit integer which
11388 counts the absolute number of HTTP response failures induced by servers
11389 which matched this entry. Errors are counted on invalid and truncated
11390 responses, as well as any 5xx response other than 501 or 505. It aims at
11391 being used combined with path or URI to detect service failures.
11392
11393 - http_fail_rate(<period>) : frequency counter (takes 12 bytes). It takes
11394 an integer parameter <period> which indicates in milliseconds the length
11395 of the period over which the average is measured. It reports the average
11396 HTTP response failure rate over that period, in requests per period (see
11397 http_fail_cnt above for what is accounted as a failure). The result is an
11398 integer which can be matched using ACLs.
11399
Willy Tarreauc9705a12010-07-27 20:05:50 +020011400 - bytes_in_cnt : client to server byte count. It is a positive 64-bit
Davor Ocelice9ed2812017-12-25 17:49:28 +010011401 integer which counts the cumulative number of bytes received from clients
Willy Tarreauc9705a12010-07-27 20:05:50 +020011402 which matched this entry. Headers are included in the count. This may be
11403 used to limit abuse of upload features on photo or video servers.
11404
11405 - bytes_in_rate(<period>) : frequency counter (takes 12 bytes). It takes an
11406 integer parameter <period> which indicates in milliseconds the length
11407 of the period over which the average is measured. It reports the average
11408 incoming bytes rate over that period, in bytes per period. It may be used
11409 to detect users which upload too much and too fast. Warning: with large
11410 uploads, it is possible that the amount of uploaded data will be counted
11411 once upon termination, thus causing spikes in the average transfer speed
11412 instead of having a smooth one. This may partially be smoothed with
11413 "option contstats" though this is not perfect yet. Use of byte_in_cnt is
11414 recommended for better fairness.
11415
11416 - bytes_out_cnt : server to client byte count. It is a positive 64-bit
Davor Ocelice9ed2812017-12-25 17:49:28 +010011417 integer which counts the cumulative number of bytes sent to clients which
Willy Tarreauc9705a12010-07-27 20:05:50 +020011418 matched this entry. Headers are included in the count. This may be used
11419 to limit abuse of bots sucking the whole site.
11420
11421 - bytes_out_rate(<period>) : frequency counter (takes 12 bytes). It takes
11422 an integer parameter <period> which indicates in milliseconds the length
11423 of the period over which the average is measured. It reports the average
11424 outgoing bytes rate over that period, in bytes per period. It may be used
11425 to detect users which download too much and too fast. Warning: with large
11426 transfers, it is possible that the amount of transferred data will be
11427 counted once upon termination, thus causing spikes in the average
11428 transfer speed instead of having a smooth one. This may partially be
11429 smoothed with "option contstats" though this is not perfect yet. Use of
11430 byte_out_cnt is recommended for better fairness.
Willy Tarreau08d5f982010-06-06 13:34:54 +020011431
Willy Tarreauc00cdc22010-06-06 16:48:26 +020011432 There is only one stick-table per proxy. At the moment of writing this doc,
11433 it does not seem useful to have multiple tables per proxy. If this happens
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011434 to be required, simply create a dummy backend with a stick-table in it and
11435 reference it.
11436
11437 It is important to understand that stickiness based on learning information
11438 has some limitations, including the fact that all learned associations are
Baptiste Assmann123ff042016-03-06 23:29:28 +010011439 lost upon restart unless peers are properly configured to transfer such
11440 information upon restart (recommended). In general it can be good as a
11441 complement but not always as an exclusive stickiness.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011442
Willy Tarreauc9705a12010-07-27 20:05:50 +020011443 Last, memory requirements may be important when storing many data types.
11444 Indeed, storing all indicators above at once in each entry requires 116 bytes
11445 per entry, or 116 MB for a 1-million entries table. This is definitely not
11446 something that can be ignored.
11447
11448 Example:
11449 # Keep track of counters of up to 1 million IP addresses over 5 minutes
11450 # and store a general purpose counter and the average connection rate
11451 # computed over a sliding window of 30 seconds.
11452 stick-table type ip size 1m expire 5m store gpc0,conn_rate(30s)
11453
Willy Tarreau4b103022021-02-12 17:59:10 +010011454 See also : "stick match", "stick on", "stick store-request", section 2.5
David du Colombiera13d1b92011-03-17 10:40:22 +010011455 about time format and section 7 about ACLs.
Willy Tarreaub937b7e2010-01-12 15:27:54 +010011456
11457
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011458stick store-response <pattern> [table <table>] [{if | unless} <condition>]
Baptiste Assmann2f2d2ec2016-03-06 23:27:24 +010011459 Define a response pattern used to create an entry in a stickiness table
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011460 May be used in sections : defaults | frontend | listen | backend
11461 no | no | yes | yes
11462
11463 Arguments :
Willy Tarreaube722a22014-06-13 16:31:59 +020011464 <pattern> is a sample expression rule as described in section 7.3. It
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011465 describes what elements of the response or connection will
Davor Ocelice9ed2812017-12-25 17:49:28 +010011466 be analyzed, extracted and stored in the table once a
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011467 server is selected.
11468
11469 <table> is an optional stickiness table name. If unspecified, the same
11470 backend's table is used. A stickiness table is declared using
11471 the "stick-table" statement.
11472
11473 <cond> is an optional storage condition. It makes it possible to store
11474 certain criteria only when some conditions are met (or not met).
11475 For instance, it could be used to store the SSL session ID only
11476 when the response is a SSL server hello.
11477
11478 Some protocols or applications require complex stickiness rules and cannot
11479 always simply rely on cookies nor hashing. The "stick store-response"
11480 statement describes a rule to decide what to extract from the response and
11481 when to do it, in order to store it into a stickiness table for further
11482 requests to match it using the "stick match" statement. Obviously the
11483 extracted part must make sense and have a chance to be matched in a further
Cyril Bonté108cf6e2012-04-21 23:30:29 +020011484 request. Storing an ID found in a header of a response makes sense.
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011485 See section 7 for a complete list of possible patterns and transformation
11486 rules.
11487
11488 The table has to be declared using the "stick-table" statement. It must be of
11489 a type compatible with the pattern. By default it is the one which is present
11490 in the same backend. It is possible to share a table with other backends by
11491 referencing it using the "table" keyword. If another table is referenced,
11492 the server's ID inside the backends are used. By default, all server IDs
11493 start at 1 in each backend, so the server ordering is enough. But in case of
11494 doubt, it is highly recommended to force server IDs using their "id" setting.
11495
11496 It is possible to restrict the conditions where a "stick store-response"
11497 statement will apply, using "if" or "unless" followed by a condition. This
11498 condition will be evaluated while parsing the response, so any criteria can
11499 be used. See section 7 for ACL based conditions.
11500
11501 There is no limit on the number of "stick store-response" statements, but
11502 there is a limit of 8 simultaneous stores per request or response. This
11503 makes it possible to store up to 8 criteria, all extracted from either the
11504 request or the response, regardless of the number of rules. Only the 8 first
11505 ones which match will be kept. Using this, it is possible to feed multiple
11506 tables at once in the hope to increase the chance to recognize a user on
Willy Tarreau9667a802013-12-09 12:52:13 +010011507 another protocol or access method. Using multiple store-response rules with
11508 the same table is possible and may be used to find the best criterion to rely
11509 on, by arranging the rules by decreasing preference order. Only the first
11510 extracted criterion for a given table will be stored. All subsequent store-
11511 response rules referencing the same table will be skipped and their ACLs will
11512 not be evaluated. However, even if a store-request rule references a table, a
11513 store-response rule may also use the same table. This means that each table
11514 may learn exactly one element from the request and one element from the
11515 response at once.
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011516
11517 The table will contain the real server that processed the request.
11518
11519 Example :
11520 # Learn SSL session ID from both request and response and create affinity.
11521 backend https
11522 mode tcp
11523 balance roundrobin
Cyril Bontédc4d9032012-04-08 21:57:39 +020011524 # maximum SSL session ID length is 32 bytes.
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011525 stick-table type binary len 32 size 30k expire 30m
Cyril Bonté108cf6e2012-04-21 23:30:29 +020011526
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011527 acl clienthello req_ssl_hello_type 1
11528 acl serverhello rep_ssl_hello_type 2
11529
11530 # use tcp content accepts to detects ssl client and server hello.
11531 tcp-request inspect-delay 5s
11532 tcp-request content accept if clienthello
11533
11534 # no timeout on response inspect delay by default.
11535 tcp-response content accept if serverhello
Cyril Bonté108cf6e2012-04-21 23:30:29 +020011536
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011537 # SSL session ID (SSLID) may be present on a client or server hello.
11538 # Its length is coded on 1 byte at offset 43 and its value starts
11539 # at offset 44.
11540
11541 # Match and learn on request if client hello.
11542 stick on payload_lv(43,1) if clienthello
11543
11544 # Learn on response if server hello.
11545 stick store-response payload_lv(43,1) if serverhello
Cyril Bontédc4d9032012-04-08 21:57:39 +020011546
Emeric Brun6a1cefa2010-09-24 18:15:17 +020011547 server s1 192.168.1.1:443
11548 server s2 192.168.1.1:443
11549
11550 See also : "stick-table", "stick on", and section 7 about ACLs and pattern
11551 extraction.
11552
11553
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011554tcp-check comment <string>
11555 Defines a comment for the following the tcp-check rule, reported in logs if
11556 it fails.
11557 May be used in sections : defaults | frontend | listen | backend
11558 yes | no | yes | yes
11559
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011560 Arguments :
11561 <string> is the comment message to add in logs if the following tcp-check
11562 rule fails.
11563
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011564 It only works for connect, send and expect rules. It is useful to make
11565 user-friendly error reporting.
11566
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011567 See also : "option tcp-check", "tcp-check connect", "tcp-check send" and
11568 "tcp-check expect".
11569
11570
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011571tcp-check connect [default] [port <expr>] [addr <ip>] [send-proxy] [via-socks4]
11572 [ssl] [sni <sni>] [alpn <alpn>] [linger]
Christopher Fauletedc6ed92020-04-23 16:27:59 +020011573 [proto <name>] [comment <msg>]
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011574 Opens a new connection
11575 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011576 yes | no | yes | yes
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011577
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011578 Arguments :
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011579 comment <msg> defines a message to report if the rule evaluation fails.
11580
Christopher Faulet4dce5922020-03-30 13:54:42 +020011581 default Use default options of the server line to do the health
Daniel Corbett67a82712020-07-06 23:01:19 -040011582 checks. The server options are used only if not redefined.
Christopher Faulet4dce5922020-03-30 13:54:42 +020011583
Christopher Fauletb7d30092020-03-30 15:19:03 +020011584 port <expr> if not set, check port or server port is used.
Christopher Faulet5c288742020-03-31 08:15:58 +020011585 It tells HAProxy where to open the connection to.
11586 <port> must be a valid TCP port source integer, from 1 to
Christopher Fauletb7d30092020-03-30 15:19:03 +020011587 65535 or an sample-fetch expression.
Christopher Faulet5c288742020-03-31 08:15:58 +020011588
11589 addr <ip> defines the IP address to do the health check.
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011590
11591 send-proxy send a PROXY protocol string
11592
Christopher Faulet085426a2020-03-30 13:07:02 +020011593 via-socks4 enables outgoing health checks using upstream socks4 proxy.
11594
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011595 ssl opens a ciphered connection
11596
Christopher Faulet79b31d42020-03-30 13:00:05 +020011597 sni <sni> specifies the SNI to use to do health checks over SSL.
11598
Christopher Faulet98572322020-03-30 13:16:44 +020011599 alpn <alpn> defines which protocols to advertise with ALPN. The protocol
11600 list consists in a comma-delimited list of protocol names,
11601 for instance: "http/1.1,http/1.0" (without quotes).
11602 If it is not set, the server ALPN is used.
11603
Christopher Fauletedc6ed92020-04-23 16:27:59 +020011604 proto <name> forces the multiplexer's protocol to use for this connection.
11605 It must be a TCP mux protocol and it must be usable on the
11606 backend side. The list of available protocols is reported in
11607 haproxy -vv.
11608
Christopher Faulet5c288742020-03-31 08:15:58 +020011609 linger cleanly close the connection instead of using a single RST.
Gaetan Rivetf8ba6772020-02-07 15:37:17 +010011610
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011611 When an application lies on more than a single TCP port or when HAProxy
11612 load-balance many services in a single backend, it makes sense to probe all
11613 the services individually before considering a server as operational.
11614
11615 When there are no TCP port configured on the server line neither server port
11616 directive, then the 'tcp-check connect port <port>' must be the first step
11617 of the sequence.
11618
11619 In a tcp-check ruleset a 'connect' is required, it is also mandatory to start
11620 the ruleset with a 'connect' rule. Purpose is to ensure admin know what they
11621 do.
11622
11623 When a connect must start the ruleset, if may still be preceded by set-var,
11624 unset-var or comment rules.
11625
11626 Examples :
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011627 # check HTTP and HTTPs services on a server.
11628 # first open port 80 thanks to server line port directive, then
11629 # tcp-check opens port 443, ciphered and run a request on it:
11630 option tcp-check
11631 tcp-check connect
11632 tcp-check send GET\ /\ HTTP/1.0\r\n
11633 tcp-check send Host:\ haproxy.1wt.eu\r\n
11634 tcp-check send \r\n
11635 tcp-check expect rstring (2..|3..)
11636 tcp-check connect port 443 ssl
11637 tcp-check send GET\ /\ HTTP/1.0\r\n
11638 tcp-check send Host:\ haproxy.1wt.eu\r\n
11639 tcp-check send \r\n
11640 tcp-check expect rstring (2..|3..)
11641 server www 10.0.0.1 check port 80
11642
11643 # check both POP and IMAP from a single server:
11644 option tcp-check
Gaetan Rivetf8ba6772020-02-07 15:37:17 +010011645 tcp-check connect port 110 linger
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011646 tcp-check expect string +OK\ POP3\ ready
11647 tcp-check connect port 143
11648 tcp-check expect string *\ OK\ IMAP4\ ready
11649 server mail 10.0.0.1 check
11650
11651 See also : "option tcp-check", "tcp-check send", "tcp-check expect"
11652
11653
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011654tcp-check expect [min-recv <int>] [comment <msg>]
Christopher Fauletec07e382020-04-07 14:56:26 +020011655 [ok-status <st>] [error-status <st>] [tout-status <st>]
Christopher Faulet98cc57c2020-04-01 20:52:31 +020011656 [on-success <fmt>] [on-error <fmt>] [status-code <expr>]
Christopher Fauletcf80f2f2020-04-01 11:04:52 +020011657 [!] <match> <pattern>
Davor Ocelice9ed2812017-12-25 17:49:28 +010011658 Specify data to be collected and analyzed during a generic health check
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011659 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011660 yes | no | yes | yes
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011661
11662 Arguments :
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011663 comment <msg> defines a message to report if the rule evaluation fails.
11664
Gaetan Rivet1afd8262020-02-07 15:37:17 +010011665 min-recv is optional and can define the minimum amount of data required to
11666 evaluate the current expect rule. If the number of received bytes
11667 is under this limit, the check will wait for more data. This
11668 option can be used to resolve some ambiguous matching rules or to
11669 avoid executing costly regex matches on content known to be still
11670 incomplete. If an exact string (string or binary) is used, the
11671 minimum between the string length and this parameter is used.
11672 This parameter is ignored if it is set to -1. If the expect rule
11673 does not match, the check will wait for more data. If set to 0,
11674 the evaluation result is always conclusive.
11675
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011676 <match> is a keyword indicating how to look for a specific pattern in the
Gaetan Rivetefab6c62020-02-07 15:37:17 +010011677 response. The keyword may be one of "string", "rstring", "binary" or
11678 "rbinary".
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011679 The keyword may be preceded by an exclamation mark ("!") to negate
11680 the match. Spaces are allowed between the exclamation mark and the
11681 keyword. See below for more details on the supported keywords.
11682
Christopher Fauletec07e382020-04-07 14:56:26 +020011683 ok-status <st> is optional and can be used to set the check status if
11684 the expect rule is successfully evaluated and if it is
11685 the last rule in the tcp-check ruleset. "L7OK", "L7OKC",
Christopher Fauletd888f0f2020-05-07 07:40:17 +020011686 "L6OK" and "L4OK" are supported :
11687 - L7OK : check passed on layer 7
Christopher Faulet83662b52020-11-20 17:47:47 +010011688 - L7OKC : check conditionally passed on layer 7, set
11689 server to NOLB state.
Christopher Fauletd888f0f2020-05-07 07:40:17 +020011690 - L6OK : check passed on layer 6
11691 - L4OK : check passed on layer 4
Christopher Fauletec07e382020-04-07 14:56:26 +020011692 By default "L7OK" is used.
11693
Christopher Fauletcf80f2f2020-04-01 11:04:52 +020011694 error-status <st> is optional and can be used to set the check status if
11695 an error occurred during the expect rule evaluation.
Christopher Faulet83662b52020-11-20 17:47:47 +010011696 "L7OKC", "L7RSP", "L7STS", "L6RSP" and "L4CON" are
11697 supported :
11698 - L7OKC : check conditionally passed on layer 7, set
11699 server to NOLB state.
Christopher Fauletd888f0f2020-05-07 07:40:17 +020011700 - L7RSP : layer 7 invalid response - protocol error
11701 - L7STS : layer 7 response error, for example HTTP 5xx
11702 - L6RSP : layer 6 invalid response - protocol error
11703 - L4CON : layer 1-4 connection problem
11704 By default "L7RSP" is used.
Christopher Fauletcf80f2f2020-04-01 11:04:52 +020011705
Christopher Fauletec07e382020-04-07 14:56:26 +020011706 tout-status <st> is optional and can be used to set the check status if
Christopher Fauletcf80f2f2020-04-01 11:04:52 +020011707 a timeout occurred during the expect rule evaluation.
Christopher Fauletd888f0f2020-05-07 07:40:17 +020011708 "L7TOUT", "L6TOUT", and "L4TOUT" are supported :
11709 - L7TOUT : layer 7 (HTTP/SMTP) timeout
11710 - L6TOUT : layer 6 (SSL) timeout
11711 - L4TOUT : layer 1-4 timeout
Christopher Fauletcf80f2f2020-04-01 11:04:52 +020011712 By default "L7TOUT" is used.
11713
Christopher Fauletbe52b4d2020-04-01 16:30:22 +020011714 on-success <fmt> is optional and can be used to customize the
11715 informational message reported in logs if the expect
11716 rule is successfully evaluated and if it is the last rule
11717 in the tcp-check ruleset. <fmt> is a log-format string.
11718
11719 on-error <fmt> is optional and can be used to customize the
11720 informational message reported in logs if an error
11721 occurred during the expect rule evaluation. <fmt> is a
11722 log-format string.
11723
Christopher Faulet98cc57c2020-04-01 20:52:31 +020011724 status-code <expr> is optional and can be used to set the check status code
11725 reported in logs, on success or on error. <expr> is a
11726 standard HAProxy expression formed by a sample-fetch
11727 followed by some converters.
11728
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011729 <pattern> is the pattern to look for. It may be a string or a regular
11730 expression. If the pattern contains spaces, they must be escaped
11731 with the usual backslash ('\').
11732 If the match is set to binary, then the pattern must be passed as
Davor Ocelice9ed2812017-12-25 17:49:28 +010011733 a series of hexadecimal digits in an even number. Each sequence of
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011734 two digits will represent a byte. The hexadecimal digits may be
11735 used upper or lower case.
11736
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011737 The available matches are intentionally similar to their http-check cousins :
11738
11739 string <string> : test the exact string matches in the response buffer.
11740 A health check response will be considered valid if the
11741 response's buffer contains this exact string. If the
11742 "string" keyword is prefixed with "!", then the response
11743 will be considered invalid if the body contains this
11744 string. This can be used to look for a mandatory pattern
11745 in a protocol response, or to detect a failure when a
11746 specific error appears in a protocol banner.
11747
11748 rstring <regex> : test a regular expression on the response buffer.
11749 A health check response will be considered valid if the
11750 response's buffer matches this expression. If the
11751 "rstring" keyword is prefixed with "!", then the response
11752 will be considered invalid if the body matches the
11753 expression.
11754
Christopher Fauletaaab0832020-05-05 15:54:22 +020011755 string-lf <fmt> : test a log-format string match in the response's buffer.
11756 A health check response will be considered valid if the
11757 response's buffer contains the string resulting of the
11758 evaluation of <fmt>, which follows the log-format rules.
11759 If prefixed with "!", then the response will be
11760 considered invalid if the buffer contains the string.
11761
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011762 binary <hexstring> : test the exact string in its hexadecimal form matches
11763 in the response buffer. A health check response will
11764 be considered valid if the response's buffer contains
11765 this exact hexadecimal string.
11766 Purpose is to match data on binary protocols.
11767
Gaetan Rivetefab6c62020-02-07 15:37:17 +010011768 rbinary <regex> : test a regular expression on the response buffer, like
11769 "rstring". However, the response buffer is transformed
11770 into its hexadecimal form, including NUL-bytes. This
11771 allows using all regex engines to match any binary
11772 content. The hexadecimal transformation takes twice the
11773 size of the original response. As such, the expected
11774 pattern should work on at-most half the response buffer
11775 size.
11776
Christopher Fauletaaab0832020-05-05 15:54:22 +020011777 binary-lf <hexfmt> : test a log-format string in its hexadecimal form
11778 match in the response's buffer. A health check response
11779 will be considered valid if the response's buffer
11780 contains the hexadecimal string resulting of the
11781 evaluation of <fmt>, which follows the log-format
11782 rules. If prefixed with "!", then the response will be
11783 considered invalid if the buffer contains the
11784 hexadecimal string. The hexadecimal string is converted
11785 in a binary string before matching the response's
11786 buffer.
11787
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011788 It is important to note that the responses will be limited to a certain size
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +010011789 defined by the global "tune.bufsize" option, which defaults to 16384 bytes.
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011790 Thus, too large responses may not contain the mandatory pattern when using
11791 "string", "rstring" or binary. If a large response is absolutely required, it
11792 is possible to change the default max size by setting the global variable.
11793 However, it is worth keeping in mind that parsing very large responses can
11794 waste some CPU cycles, especially when regular expressions are used, and that
11795 it is always better to focus the checks on smaller resources. Also, in its
11796 current state, the check will not find any string nor regex past a null
11797 character in the response. Similarly it is not possible to request matching
11798 the null character.
11799
11800 Examples :
11801 # perform a POP check
11802 option tcp-check
11803 tcp-check expect string +OK\ POP3\ ready
11804
11805 # perform an IMAP check
11806 option tcp-check
11807 tcp-check expect string *\ OK\ IMAP4\ ready
11808
11809 # look for the redis master server
11810 option tcp-check
11811 tcp-check send PING\r\n
Baptiste Assmanna3322992015-08-04 10:12:18 +020011812 tcp-check expect string +PONG
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011813 tcp-check send info\ replication\r\n
11814 tcp-check expect string role:master
11815 tcp-check send QUIT\r\n
11816 tcp-check expect string +OK
11817
11818
11819 See also : "option tcp-check", "tcp-check connect", "tcp-check send",
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +010011820 "tcp-check send-binary", "http-check expect", tune.bufsize
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011821
11822
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011823tcp-check send <data> [comment <msg>]
11824tcp-check send-lf <fmt> [comment <msg>]
11825 Specify a string or a log-format string to be sent as a question during a
11826 generic health check
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011827 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011828 yes | no | yes | yes
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011829
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011830 Arguments :
11831 comment <msg> defines a message to report if the rule evaluation fails.
11832
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011833 <data> is the string that will be sent during a generic health
11834 check session.
Christopher Faulet16fff672020-04-30 07:50:54 +020011835
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011836 <fmt> is the log-format string that will be sent, once evaluated,
11837 during a generic health check session.
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011838
11839 Examples :
11840 # look for the redis master server
11841 option tcp-check
11842 tcp-check send info\ replication\r\n
11843 tcp-check expect string role:master
11844
11845 See also : "option tcp-check", "tcp-check connect", "tcp-check expect",
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +010011846 "tcp-check send-binary", tune.bufsize
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011847
11848
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011849tcp-check send-binary <hexstring> [comment <msg>]
11850tcp-check send-binary-lf <hexfmt> [comment <msg>]
11851 Specify an hex digits string or an hex digits log-format string to be sent as
11852 a binary question during a raw tcp health check
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011853 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011854 yes | no | yes | yes
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011855
Christopher Faulet4f5c2e22020-04-23 15:22:33 +020011856 Arguments :
11857 comment <msg> defines a message to report if the rule evaluation fails.
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011858
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011859 <hexstring> is the hexadecimal string that will be send, once converted
11860 to binary, during a generic health check session.
Christopher Faulet16fff672020-04-30 07:50:54 +020011861
Christopher Fauletb50b3e62020-05-05 18:43:43 +020011862 <hexfmt> is the hexadecimal log-format string that will be send, once
11863 evaluated and converted to binary, during a generic health
11864 check session.
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011865
11866 Examples :
11867 # redis check in binary
11868 option tcp-check
11869 tcp-check send-binary 50494e470d0a # PING\r\n
11870 tcp-check expect binary 2b504F4e47 # +PONG
11871
11872
11873 See also : "option tcp-check", "tcp-check connect", "tcp-check expect",
Christopher Fauletbb9fb8b2020-11-25 17:20:57 +010011874 "tcp-check send", tune.bufsize
Willy Tarreau938c7fe2014-04-25 14:21:39 +020011875
11876
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011877tcp-check set-var(<var-name>) <expr>
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011878 This operation sets the content of a variable. The variable is declared inline.
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011879 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011880 yes | no | yes | yes
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011881
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011882 Arguments :
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011883 <var-name> The name of the variable starts with an indication about its
11884 scope. The scopes allowed for tcp-check are:
11885 "proc" : the variable is shared with the whole process.
11886 "sess" : the variable is shared with the tcp-check session.
11887 "check": the variable is declared for the lifetime of the tcp-check.
11888 This prefix is followed by a name. The separator is a '.'.
11889 The name may only contain characters 'a-z', 'A-Z', '0-9', '.',
11890 and '-'.
11891
11892 <expr> Is a sample-fetch expression potentially followed by converters.
11893
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011894 Examples :
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011895 tcp-check set-var(check.port) int(1234)
11896
11897
11898tcp-check unset-var(<var-name>)
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011899 Free a reference to a variable within its scope.
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011900 May be used in sections: defaults | frontend | listen | backend
Christopher Faulet404f9192020-04-09 23:13:54 +020011901 yes | no | yes | yes
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011902
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011903 Arguments :
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011904 <var-name> The name of the variable starts with an indication about its
11905 scope. The scopes allowed for tcp-check are:
11906 "proc" : the variable is shared with the whole process.
11907 "sess" : the variable is shared with the tcp-check session.
11908 "check": the variable is declared for the lifetime of the tcp-check.
11909 This prefix is followed by a name. The separator is a '.'.
11910 The name may only contain characters 'a-z', 'A-Z', '0-9', '.',
11911 and '-'.
11912
Christopher Fauletc52ea4d2020-04-23 15:43:35 +020011913 Examples :
Gaetan Rivet0c39ecc2020-02-24 17:34:11 +010011914 tcp-check unset-var(check.port)
11915
11916
Willy Tarreaue9656522010-08-17 15:40:09 +020011917tcp-request connection <action> [{if | unless} <condition>]
11918 Perform an action on an incoming connection depending on a layer 4 condition
Willy Tarreau1a687942010-05-23 22:40:30 +020011919 May be used in sections : defaults | frontend | listen | backend
11920 no | yes | yes | no
Willy Tarreaue9656522010-08-17 15:40:09 +020011921 Arguments :
Willy Tarreauc870bfd2015-09-28 18:47:38 +020011922 <action> defines the action to perform if the condition applies. See
11923 below.
Willy Tarreau1a687942010-05-23 22:40:30 +020011924
Willy Tarreaue9656522010-08-17 15:40:09 +020011925 <condition> is a standard layer4-only ACL-based condition (see section 7).
Willy Tarreau68c03ab2010-08-06 15:08:45 +020011926
11927 Immediately after acceptance of a new incoming connection, it is possible to
11928 evaluate some conditions to decide whether this connection must be accepted
Willy Tarreaue9656522010-08-17 15:40:09 +020011929 or dropped or have its counters tracked. Those conditions cannot make use of
11930 any data contents because the connection has not been read from yet, and the
11931 buffers are not yet allocated. This is used to selectively and very quickly
11932 accept or drop connections from various sources with a very low overhead. If
11933 some contents need to be inspected in order to take the decision, the
11934 "tcp-request content" statements must be used instead.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020011935
Willy Tarreaue9656522010-08-17 15:40:09 +020011936 The "tcp-request connection" rules are evaluated in their exact declaration
11937 order. If no rule matches or if there is no rule, the default action is to
11938 accept the incoming connection. There is no specific limit to the number of
11939 rules which may be inserted.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020011940
Willy Tarreaua9083d02015-05-08 15:27:59 +020011941 Four types of actions are supported :
Willy Tarreaue9656522010-08-17 15:40:09 +020011942 - accept :
11943 accepts the connection if the condition is true (when used with "if")
11944 or false (when used with "unless"). The first such rule executed ends
11945 the rules evaluation.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020011946
Willy Tarreaue9656522010-08-17 15:40:09 +020011947 - reject :
11948 rejects the connection if the condition is true (when used with "if")
11949 or false (when used with "unless"). The first such rule executed ends
11950 the rules evaluation. Rejected connections do not even become a
11951 session, which is why they are accounted separately for in the stats,
11952 as "denied connections". They are not considered for the session
11953 rate-limit and are not logged either. The reason is that these rules
11954 should only be used to filter extremely high connection rates such as
11955 the ones encountered during a massive DDoS attack. Under these extreme
11956 conditions, the simple action of logging each event would make the
11957 system collapse and would considerably lower the filtering capacity. If
11958 logging is absolutely desired, then "tcp-request content" rules should
Willy Tarreau4f614292016-10-21 17:49:36 +020011959 be used instead, as "tcp-request session" rules will not log either.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020011960
Willy Tarreau4f0d9192013-06-11 20:40:55 +020011961 - expect-proxy layer4 :
11962 configures the client-facing connection to receive a PROXY protocol
11963 header before any byte is read from the socket. This is equivalent to
11964 having the "accept-proxy" keyword on the "bind" line, except that using
11965 the TCP rule allows the PROXY protocol to be accepted only for certain
11966 IP address ranges using an ACL. This is convenient when multiple layers
11967 of load balancers are passed through by traffic coming from public
11968 hosts.
11969
Bertrand Jacquin90759682016-06-06 15:35:39 +010011970 - expect-netscaler-cip layer4 :
11971 configures the client-facing connection to receive a NetScaler Client
11972 IP insertion protocol header before any byte is read from the socket.
11973 This is equivalent to having the "accept-netscaler-cip" keyword on the
11974 "bind" line, except that using the TCP rule allows the PROXY protocol
11975 to be accepted only for certain IP address ranges using an ACL. This
11976 is convenient when multiple layers of load balancers are passed
11977 through by traffic coming from public hosts.
11978
Willy Tarreau18bf01e2014-06-13 16:18:52 +020011979 - capture <sample> len <length> :
11980 This only applies to "tcp-request content" rules. It captures sample
11981 expression <sample> from the request buffer, and converts it to a
11982 string of at most <len> characters. The resulting string is stored into
11983 the next request "capture" slot, so it will possibly appear next to
11984 some captured HTTP headers. It will then automatically appear in the
11985 logs, and it will be possible to extract it using sample fetch rules to
11986 feed it into headers or anything. The length should be limited given
11987 that this size will be allocated for each capture during the whole
Willy Tarreaua9083d02015-05-08 15:27:59 +020011988 session life. Please check section 7.3 (Fetching samples) and "capture
11989 request header" for more information.
Willy Tarreau18bf01e2014-06-13 16:18:52 +020011990
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020011991 - { track-sc0 | track-sc1 | track-sc2 } <key> [table <table>] :
Willy Tarreaue9656522010-08-17 15:40:09 +020011992 enables tracking of sticky counters from current connection. These
Moemen MHEDHBI9cf46342018-09-25 17:50:53 +020011993 rules do not stop evaluation and do not change default action. The
11994 number of counters that may be simultaneously tracked by the same
11995 connection is set in MAX_SESS_STKCTR at build time (reported in
John Roeslerfb2fce12019-07-10 15:45:51 -050011996 haproxy -vv) which defaults to 3, so the track-sc number is between 0
Matteo Contrini1857b8c2020-10-16 17:35:54 +020011997 and (MAX_SESS_STKCTR-1). The first "track-sc0" rule executed enables
Moemen MHEDHBI9cf46342018-09-25 17:50:53 +020011998 tracking of the counters of the specified table as the first set. The
11999 first "track-sc1" rule executed enables tracking of the counters of the
12000 specified table as the second set. The first "track-sc2" rule executed
12001 enables tracking of the counters of the specified table as the third
12002 set. It is a recommended practice to use the first set of counters for
12003 the per-frontend counters and the second set for the per-backend ones.
12004 But this is just a guideline, all may be used everywhere.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012005
Willy Tarreaue9656522010-08-17 15:40:09 +020012006 These actions take one or two arguments :
Willy Tarreaube722a22014-06-13 16:31:59 +020012007 <key> is mandatory, and is a sample expression rule as described
Willy Tarreau74ca5042013-06-11 23:12:07 +020012008 in section 7.3. It describes what elements of the incoming
Davor Ocelice9ed2812017-12-25 17:49:28 +010012009 request or connection will be analyzed, extracted, combined,
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012010 and used to select which table entry to update the counters.
12011 Note that "tcp-request connection" cannot use content-based
12012 fetches.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012013
Willy Tarreaue9656522010-08-17 15:40:09 +020012014 <table> is an optional table to be used instead of the default one,
12015 which is the stick-table declared in the current proxy. All
12016 the counters for the matches and updates for the key will
12017 then be performed in that table until the session ends.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012018
Willy Tarreaue9656522010-08-17 15:40:09 +020012019 Once a "track-sc*" rule is executed, the key is looked up in the table
12020 and if it is not found, an entry is allocated for it. Then a pointer to
12021 that entry is kept during all the session's life, and this entry's
12022 counters are updated as often as possible, every time the session's
12023 counters are updated, and also systematically when the session ends.
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012024 Counters are only updated for events that happen after the tracking has
12025 been started. For example, connection counters will not be updated when
12026 tracking layer 7 information, since the connection event happens before
12027 layer7 information is extracted.
12028
Willy Tarreaue9656522010-08-17 15:40:09 +020012029 If the entry tracks concurrent connection counters, one connection is
12030 counted for as long as the entry is tracked, and the entry will not
12031 expire during that time. Tracking counters also provides a performance
12032 advantage over just checking the keys, because only one table lookup is
12033 performed for all ACL checks that make use of it.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012034
Thierry FOURNIERe0627bd2015-08-04 08:20:33 +020012035 - sc-inc-gpc0(<sc-id>):
12036 The "sc-inc-gpc0" increments the GPC0 counter according to the sticky
12037 counter designated by <sc-id>. If an error occurs, this action silently
12038 fails and the actions evaluation continues.
12039
Frédéric Lécaille6778b272018-01-29 15:22:53 +010012040 - sc-inc-gpc1(<sc-id>):
12041 The "sc-inc-gpc1" increments the GPC1 counter according to the sticky
12042 counter designated by <sc-id>. If an error occurs, this action silently
12043 fails and the actions evaluation continues.
12044
Cédric Dufour0d7712d2019-11-06 18:38:53 +010012045 - sc-set-gpt0(<sc-id>) { <int> | <expr> }:
12046 This action sets the 32-bit unsigned GPT0 tag according to the sticky
12047 counter designated by <sc-id> and the value of <int>/<expr>. The
12048 expected result is a boolean. If an error occurs, this action silently
12049 fails and the actions evaluation continues.
Thierry FOURNIER236657b2015-08-19 08:25:14 +020012050
William Lallemand2e785f22016-05-25 01:48:42 +020012051 - set-src <expr> :
12052 Is used to set the source IP address to the value of specified
12053 expression. Useful if you want to mask source IP for privacy.
12054 If you want to provide an IP from a HTTP header use "http-request
Cyril Bonté6c81d5f2018-10-17 00:14:51 +020012055 set-src".
William Lallemand2e785f22016-05-25 01:48:42 +020012056
Cyril Bonté6c81d5f2018-10-17 00:14:51 +020012057 Arguments:
12058 <expr> Is a standard HAProxy expression formed by a sample-fetch
12059 followed by some converters.
William Lallemand2e785f22016-05-25 01:48:42 +020012060
12061 Example:
William Lallemand2e785f22016-05-25 01:48:42 +020012062 tcp-request connection set-src src,ipmask(24)
12063
Willy Tarreau0c630532016-10-21 17:52:58 +020012064 When possible, set-src preserves the original source port as long as the
12065 address family allows it, otherwise the source port is set to 0.
William Lallemand2e785f22016-05-25 01:48:42 +020012066
William Lallemand44be6402016-05-25 01:51:35 +020012067 - set-src-port <expr> :
12068 Is used to set the source port address to the value of specified
12069 expression.
12070
Cyril Bonté6c81d5f2018-10-17 00:14:51 +020012071 Arguments:
12072 <expr> Is a standard HAProxy expression formed by a sample-fetch
12073 followed by some converters.
William Lallemand44be6402016-05-25 01:51:35 +020012074
12075 Example:
William Lallemand44be6402016-05-25 01:51:35 +020012076 tcp-request connection set-src-port int(4000)
12077
Willy Tarreau0c630532016-10-21 17:52:58 +020012078 When possible, set-src-port preserves the original source address as long
12079 as the address family supports a port, otherwise it forces the source
12080 address to IPv4 "0.0.0.0" before rewriting the port.
William Lallemand44be6402016-05-25 01:51:35 +020012081
William Lallemand13e9b0c2016-05-25 02:34:07 +020012082 - set-dst <expr> :
12083 Is used to set the destination IP address to the value of specified
12084 expression. Useful if you want to mask IP for privacy in log.
12085 If you want to provide an IP from a HTTP header use "http-request
12086 set-dst". If you want to connect to the new address/port, use
12087 '0.0.0.0:0' as a server address in the backend.
12088
12089 <expr> Is a standard HAProxy expression formed by a sample-fetch
12090 followed by some converters.
12091
12092 Example:
12093
12094 tcp-request connection set-dst dst,ipmask(24)
12095 tcp-request connection set-dst ipv4(10.0.0.1)
12096
Willy Tarreau0c630532016-10-21 17:52:58 +020012097 When possible, set-dst preserves the original destination port as long as
12098 the address family allows it, otherwise the destination port is set to 0.
12099
William Lallemand13e9b0c2016-05-25 02:34:07 +020012100 - set-dst-port <expr> :
12101 Is used to set the destination port address to the value of specified
12102 expression. If you want to connect to the new address/port, use
12103 '0.0.0.0:0' as a server address in the backend.
12104
12105
12106 <expr> Is a standard HAProxy expression formed by a sample-fetch
12107 followed by some converters.
12108
12109 Example:
12110
12111 tcp-request connection set-dst-port int(4000)
12112
Willy Tarreau0c630532016-10-21 17:52:58 +020012113 When possible, set-dst-port preserves the original destination address as
12114 long as the address family supports a port, otherwise it forces the
12115 destination address to IPv4 "0.0.0.0" before rewriting the port.
12116
Willy Tarreau2d392c22015-08-24 01:43:45 +020012117 - "silent-drop" :
12118 This stops the evaluation of the rules and makes the client-facing
Davor Ocelice9ed2812017-12-25 17:49:28 +010012119 connection suddenly disappear using a system-dependent way that tries
Willy Tarreau2d392c22015-08-24 01:43:45 +020012120 to prevent the client from being notified. The effect it then that the
12121 client still sees an established connection while there's none on
12122 HAProxy. The purpose is to achieve a comparable effect to "tarpit"
12123 except that it doesn't use any local resource at all on the machine
12124 running HAProxy. It can resist much higher loads than "tarpit", and
Davor Ocelice9ed2812017-12-25 17:49:28 +010012125 slow down stronger attackers. It is important to understand the impact
12126 of using this mechanism. All stateful equipment placed between the
Willy Tarreau2d392c22015-08-24 01:43:45 +020012127 client and HAProxy (firewalls, proxies, load balancers) will also keep
12128 the established connection for a long time and may suffer from this
Davor Ocelice9ed2812017-12-25 17:49:28 +010012129 action. On modern Linux systems running with enough privileges, the
Willy Tarreau2d392c22015-08-24 01:43:45 +020012130 TCP_REPAIR socket option is used to block the emission of a TCP
12131 reset. On other systems, the socket's TTL is reduced to 1 so that the
12132 TCP reset doesn't pass the first router, though it's still delivered to
12133 local networks. Do not use it unless you fully understand how it works.
12134
Willy Tarreaue9656522010-08-17 15:40:09 +020012135 Note that the "if/unless" condition is optional. If no condition is set on
12136 the action, it is simply performed unconditionally. That can be useful for
12137 "track-sc*" actions as well as for changing the default action to a reject.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012138
Willy Tarreaue9656522010-08-17 15:40:09 +020012139 Example: accept all connections from white-listed hosts, reject too fast
12140 connection without counting them, and track accepted connections.
12141 This results in connection rate being capped from abusive sources.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012142
Willy Tarreaue9656522010-08-17 15:40:09 +020012143 tcp-request connection accept if { src -f /etc/haproxy/whitelist.lst }
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012144 tcp-request connection reject if { src_conn_rate gt 10 }
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012145 tcp-request connection track-sc0 src
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012146
Willy Tarreaue9656522010-08-17 15:40:09 +020012147 Example: accept all connections from white-listed hosts, count all other
12148 connections and reject too fast ones. This results in abusive ones
12149 being blocked as long as they don't slow down.
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012150
Willy Tarreaue9656522010-08-17 15:40:09 +020012151 tcp-request connection accept if { src -f /etc/haproxy/whitelist.lst }
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012152 tcp-request connection track-sc0 src
12153 tcp-request connection reject if { sc0_conn_rate gt 10 }
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012154
Willy Tarreau4f0d9192013-06-11 20:40:55 +020012155 Example: enable the PROXY protocol for traffic coming from all known proxies.
12156
12157 tcp-request connection expect-proxy layer4 if { src -f proxies.lst }
12158
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012159 See section 7 about ACL usage.
12160
Willy Tarreau4f614292016-10-21 17:49:36 +020012161 See also : "tcp-request session", "tcp-request content", "stick-table"
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012162
12163
Willy Tarreaue9656522010-08-17 15:40:09 +020012164tcp-request content <action> [{if | unless} <condition>]
12165 Perform an action on a new session depending on a layer 4-7 condition
Willy Tarreau62644772008-07-16 18:36:06 +020012166 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaufb356202010-08-03 14:02:05 +020012167 no | yes | yes | yes
Willy Tarreaue9656522010-08-17 15:40:09 +020012168 Arguments :
Willy Tarreauc870bfd2015-09-28 18:47:38 +020012169 <action> defines the action to perform if the condition applies. See
12170 below.
Willy Tarreau62644772008-07-16 18:36:06 +020012171
Willy Tarreaue9656522010-08-17 15:40:09 +020012172 <condition> is a standard layer 4-7 ACL-based condition (see section 7).
Willy Tarreau62644772008-07-16 18:36:06 +020012173
Davor Ocelice9ed2812017-12-25 17:49:28 +010012174 A request's contents can be analyzed at an early stage of request processing
Willy Tarreaue9656522010-08-17 15:40:09 +020012175 called "TCP content inspection". During this stage, ACL-based rules are
12176 evaluated every time the request contents are updated, until either an
Christopher Fauletae863c62021-03-15 12:03:44 +010012177 "accept", a "reject" or a "switch-mode" rule matches, or the TCP request
12178 inspection delay expires with no matching rule.
Willy Tarreau62644772008-07-16 18:36:06 +020012179
Willy Tarreaue9656522010-08-17 15:40:09 +020012180 The first difference between these rules and "tcp-request connection" rules
12181 is that "tcp-request content" rules can make use of contents to take a
12182 decision. Most often, these decisions will consider a protocol recognition or
12183 validity. The second difference is that content-based rules can be used in
Willy Tarreauf3338342014-01-28 21:40:28 +010012184 both frontends and backends. In case of HTTP keep-alive with the client, all
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012185 tcp-request content rules are evaluated again, so HAProxy keeps a record of
Willy Tarreauf3338342014-01-28 21:40:28 +010012186 what sticky counters were assigned by a "tcp-request connection" versus a
12187 "tcp-request content" rule, and flushes all the content-related ones after
12188 processing an HTTP request, so that they may be evaluated again by the rules
12189 being evaluated again for the next request. This is of particular importance
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030012190 when the rule tracks some L7 information or when it is conditioned by an
Willy Tarreauf3338342014-01-28 21:40:28 +010012191 L7-based ACL, since tracking may change between requests.
Willy Tarreau62644772008-07-16 18:36:06 +020012192
Willy Tarreaue9656522010-08-17 15:40:09 +020012193 Content-based rules are evaluated in their exact declaration order. If no
12194 rule matches or if there is no rule, the default action is to accept the
12195 contents. There is no specific limit to the number of rules which may be
12196 inserted.
Willy Tarreau62644772008-07-16 18:36:06 +020012197
Thierry FOURNIER236657b2015-08-19 08:25:14 +020012198 Several types of actions are supported :
Willy Tarreau18bf01e2014-06-13 16:18:52 +020012199 - accept : the request is accepted
Baptiste Assmann333939c2019-01-21 08:34:50 +010012200 - do-resolve: perform a DNS resolution
Willy Tarreau18bf01e2014-06-13 16:18:52 +020012201 - reject : the request is rejected and the connection is closed
12202 - capture : the specified sample expression is captured
Patrick Hemmer268a7072018-05-11 12:52:31 -040012203 - set-priority-class <expr> | set-priority-offset <expr>
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012204 - { track-sc0 | track-sc1 | track-sc2 } <key> [table <table>]
Thierry FOURNIERe0627bd2015-08-04 08:20:33 +020012205 - sc-inc-gpc0(<sc-id>)
Frédéric Lécaille6778b272018-01-29 15:22:53 +010012206 - sc-inc-gpc1(<sc-id>)
Cédric Dufour0d7712d2019-11-06 18:38:53 +010012207 - sc-set-gpt0(<sc-id>) { <int> | <expr> }
Baptiste Assmanne1afd4f2019-04-18 16:21:13 +020012208 - set-dst <expr>
12209 - set-dst-port <expr>
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012210 - set-var(<var-name>) <expr>
Christopher Fauletae863c62021-03-15 12:03:44 +010012211 - switch-mode http [ proto <name> ]
Christopher Faulet85d79c92016-11-09 16:54:56 +010012212 - unset-var(<var-name>)
Willy Tarreau2d392c22015-08-24 01:43:45 +020012213 - silent-drop
Davor Ocelice9ed2812017-12-25 17:49:28 +010012214 - send-spoe-group <engine-name> <group-name>
Christopher Faulet579d83b2019-11-22 15:34:17 +010012215 - use-service <service-name>
Willy Tarreau62644772008-07-16 18:36:06 +020012216
Willy Tarreaue9656522010-08-17 15:40:09 +020012217 They have the same meaning as their counter-parts in "tcp-request connection"
12218 so please refer to that section for a complete description.
Baptiste Assmann333939c2019-01-21 08:34:50 +010012219 For "do-resolve" action, please check the "http-request do-resolve"
12220 configuration section.
Willy Tarreau62644772008-07-16 18:36:06 +020012221
Willy Tarreauf3338342014-01-28 21:40:28 +010012222 While there is nothing mandatory about it, it is recommended to use the
12223 track-sc0 in "tcp-request connection" rules, track-sc1 for "tcp-request
12224 content" rules in the frontend, and track-sc2 for "tcp-request content"
12225 rules in the backend, because that makes the configuration more readable
12226 and easier to troubleshoot, but this is just a guideline and all counters
12227 may be used everywhere.
Willy Tarreau62644772008-07-16 18:36:06 +020012228
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010012229 Note that the "if/unless" condition is optional. If no condition is set on
Willy Tarreaue9656522010-08-17 15:40:09 +020012230 the action, it is simply performed unconditionally. That can be useful for
12231 "track-sc*" actions as well as for changing the default action to a reject.
Willy Tarreau62644772008-07-16 18:36:06 +020012232
Christopher Faulet2079a4a2020-10-02 11:48:57 +020012233 Note also that it is recommended to use a "tcp-request session" rule to track
12234 information that does *not* depend on Layer 7 contents, especially for HTTP
12235 frontends. Some HTTP processing are performed at the session level and may
12236 lead to an early rejection of the requests. Thus, the tracking at the content
12237 level may be disturbed in such case. A warning is emitted during startup to
12238 prevent, as far as possible, such unreliable usage.
12239
Willy Tarreaue9656522010-08-17 15:40:09 +020012240 It is perfectly possible to match layer 7 contents with "tcp-request content"
Christopher Faulet7ea509e2020-10-02 11:38:46 +020012241 rules from a TCP proxy, since HTTP-specific ACL matches are able to
12242 preliminarily parse the contents of a buffer before extracting the required
12243 data. If the buffered contents do not parse as a valid HTTP message, then the
12244 ACL does not match. The parser which is involved there is exactly the same
12245 as for all other HTTP processing, so there is no risk of parsing something
12246 differently. In an HTTP frontend or an HTTP backend, it is guaranteed that
12247 HTTP contents will always be immediately present when the rule is evaluated
12248 first because the HTTP parsing is performed in the early stages of the
12249 connection processing, at the session level. But for such proxies, using
12250 "http-request" rules is much more natural and recommended.
Willy Tarreau62644772008-07-16 18:36:06 +020012251
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012252 Tracking layer7 information is also possible provided that the information
Willy Tarreau4d54c7c2014-09-16 15:48:15 +020012253 are present when the rule is processed. The rule processing engine is able to
12254 wait until the inspect delay expires when the data to be tracked is not yet
12255 available.
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012256
Baptiste Assmanne1afd4f2019-04-18 16:21:13 +020012257 The "set-dst" and "set-dst-port" are used to set respectively the destination
12258 IP and port. More information on how to use it at "http-request set-dst".
12259
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012260 The "set-var" is used to set the content of a variable. The variable is
Willy Tarreau4f614292016-10-21 17:49:36 +020012261 declared inline. For "tcp-request session" rules, only session-level
12262 variables can be used, without any layer7 contents.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012263
Daniel Schneller0b547052016-03-21 20:46:57 +010012264 <var-name> The name of the variable starts with an indication about
12265 its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010012266 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010012267 "sess" : the variable is shared with the whole session
12268 "txn" : the variable is shared with the transaction
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012269 (request and response)
Daniel Schneller0b547052016-03-21 20:46:57 +010012270 "req" : the variable is shared only during request
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012271 processing
Daniel Schneller0b547052016-03-21 20:46:57 +010012272 "res" : the variable is shared only during response
12273 processing
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012274 This prefix is followed by a name. The separator is a '.'.
Christopher Fauletb71557a2016-10-31 10:49:03 +010012275 The name may only contain characters 'a-z', 'A-Z', '0-9',
12276 '.' and '_'.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012277
12278 <expr> Is a standard HAProxy expression formed by a sample-fetch
12279 followed by some converters.
12280
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012281 The "switch-mode" is used to perform a connection upgrade. Only HTTP
Christopher Fauletae863c62021-03-15 12:03:44 +010012282 upgrades are supported for now. The protocol may optionally be
12283 specified. This action is only available for a proxy with the frontend
12284 capability. The connection upgrade is immediately performed, following
12285 "tcp-request content" rules are not evaluated. This upgrade method should be
12286 preferred to the implicit one consisting to rely on the backend mode. When
12287 used, it is possible to set HTTP directives in a frontend without any
Ilya Shipitsin3df59892021-05-10 12:50:00 +050012288 warning. These directives will be conditionally evaluated if the HTTP upgrade
Christopher Fauletae863c62021-03-15 12:03:44 +010012289 is performed. However, an HTTP backend must still be selected. It remains
12290 unsupported to route an HTTP connection (upgraded or not) to a TCP server.
12291
Christopher Faulet4d37e532021-03-26 14:44:00 +010012292 See section 4 about Proxies for more details on HTTP upgrades.
12293
Christopher Faulet85d79c92016-11-09 16:54:56 +010012294 The "unset-var" is used to unset a variable. See above for details about
12295 <var-name>.
12296
Patrick Hemmer268a7072018-05-11 12:52:31 -040012297 The "set-priority-class" is used to set the queue priority class of the
12298 current request. The value must be a sample expression which converts to an
12299 integer in the range -2047..2047. Results outside this range will be
12300 truncated. The priority class determines the order in which queued requests
12301 are processed. Lower values have higher priority.
12302
12303 The "set-priority-offset" is used to set the queue priority timestamp offset
12304 of the current request. The value must be a sample expression which converts
12305 to an integer in the range -524287..524287. Results outside this range will be
12306 truncated. When a request is queued, it is ordered first by the priority
12307 class, then by the current timestamp adjusted by the given offset in
12308 milliseconds. Lower values have higher priority.
12309 Note that the resulting timestamp is is only tracked with enough precision for
12310 524,287ms (8m44s287ms). If the request is queued long enough to where the
12311 adjusted timestamp exceeds this value, it will be misidentified as highest
12312 priority. Thus it is important to set "timeout queue" to a value, where when
12313 combined with the offset, does not exceed this limit.
12314
Christopher Faulet76c09ef2017-09-21 11:03:52 +020012315 The "send-spoe-group" is used to trigger sending of a group of SPOE
12316 messages. To do so, the SPOE engine used to send messages must be defined, as
12317 well as the SPOE group to send. Of course, the SPOE engine must refer to an
12318 existing SPOE filter. If not engine name is provided on the SPOE filter line,
12319 the SPOE agent name must be used.
12320
12321 <engine-name> The SPOE engine name.
12322
12323 <group-name> The SPOE group name as specified in the engine configuration.
12324
Christopher Faulet579d83b2019-11-22 15:34:17 +010012325 The "use-service" is used to executes a TCP service which will reply to the
12326 request and stop the evaluation of the rules. This service may choose to
12327 reply by sending any valid response or it may immediately close the
12328 connection without sending anything. Outside natives services, it is possible
12329 to write your own services in Lua. No further "tcp-request" rules are
12330 evaluated.
12331
12332 Example:
12333 tcp-request content use-service lua.deny { src -f /etc/haproxy/blacklist.lst }
12334
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012335 Example:
12336
12337 tcp-request content set-var(sess.my_var) src
Christopher Faulet85d79c92016-11-09 16:54:56 +010012338 tcp-request content unset-var(sess.my_var2)
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012339
Willy Tarreau62644772008-07-16 18:36:06 +020012340 Example:
Willy Tarreaue9656522010-08-17 15:40:09 +020012341 # Accept HTTP requests containing a Host header saying "example.com"
Christopher Fauletae863c62021-03-15 12:03:44 +010012342 # and reject everything else. (Only works for HTTP/1 connections)
Willy Tarreaue9656522010-08-17 15:40:09 +020012343 acl is_host_com hdr(Host) -i example.com
12344 tcp-request inspect-delay 30s
Willy Tarreauc0239e02012-04-16 14:42:55 +020012345 tcp-request content accept if is_host_com
Willy Tarreaue9656522010-08-17 15:40:09 +020012346 tcp-request content reject
12347
Christopher Fauletae863c62021-03-15 12:03:44 +010012348 # Accept HTTP requests containing a Host header saying "example.com"
12349 # and reject everything else. (works for HTTP/1 and HTTP/2 connections)
12350 acl is_host_com hdr(Host) -i example.com
12351 tcp-request inspect-delay 5s
12352 tcp-request switch-mode http if HTTP
12353 tcp-request reject # non-HTTP traffic is implicit here
12354 ...
12355 http-request reject unless is_host_com
12356
Willy Tarreaue9656522010-08-17 15:40:09 +020012357 Example:
Willy Tarreau62644772008-07-16 18:36:06 +020012358 # reject SMTP connection if client speaks first
12359 tcp-request inspect-delay 30s
12360 acl content_present req_len gt 0
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012361 tcp-request content reject if content_present
Willy Tarreau62644772008-07-16 18:36:06 +020012362
12363 # Forward HTTPS connection only if client speaks
12364 tcp-request inspect-delay 30s
12365 acl content_present req_len gt 0
Willy Tarreau68c03ab2010-08-06 15:08:45 +020012366 tcp-request content accept if content_present
Willy Tarreaue9656522010-08-17 15:40:09 +020012367 tcp-request content reject
12368
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012369 Example:
Jarno Huuskonene5ae7022017-04-03 14:36:21 +030012370 # Track the last IP(stick-table type string) from X-Forwarded-For
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012371 tcp-request inspect-delay 10s
Willy Tarreau4d54c7c2014-09-16 15:48:15 +020012372 tcp-request content track-sc0 hdr(x-forwarded-for,-1)
Jarno Huuskonene5ae7022017-04-03 14:36:21 +030012373 # Or track the last IP(stick-table type ip|ipv6) from X-Forwarded-For
12374 tcp-request content track-sc0 req.hdr_ip(x-forwarded-for,-1)
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012375
12376 Example:
12377 # track request counts per "base" (concatenation of Host+URL)
12378 tcp-request inspect-delay 10s
Willy Tarreau4d54c7c2014-09-16 15:48:15 +020012379 tcp-request content track-sc0 base table req-rate
Willy Tarreau5d5b5d82012-12-09 12:00:04 +010012380
Willy Tarreaue9656522010-08-17 15:40:09 +020012381 Example: track per-frontend and per-backend counters, block abusers at the
Jarno Huuskonene5ae7022017-04-03 14:36:21 +030012382 frontend when the backend detects abuse(and marks gpc0).
Willy Tarreaue9656522010-08-17 15:40:09 +020012383
12384 frontend http
Davor Ocelice9ed2812017-12-25 17:49:28 +010012385 # Use General Purpose Counter 0 in SC0 as a global abuse counter
Willy Tarreaue9656522010-08-17 15:40:09 +020012386 # protecting all our sites
12387 stick-table type ip size 1m expire 5m store gpc0
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012388 tcp-request connection track-sc0 src
12389 tcp-request connection reject if { sc0_get_gpc0 gt 0 }
Willy Tarreaue9656522010-08-17 15:40:09 +020012390 ...
12391 use_backend http_dynamic if { path_end .php }
12392
12393 backend http_dynamic
12394 # if a source makes too fast requests to this dynamic site (tracked
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012395 # by SC1), block it globally in the frontend.
Willy Tarreaue9656522010-08-17 15:40:09 +020012396 stick-table type ip size 1m expire 5m store http_req_rate(10s)
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012397 acl click_too_fast sc1_http_req_rate gt 10
Jarno Huuskonene5ae7022017-04-03 14:36:21 +030012398 acl mark_as_abuser sc0_inc_gpc0(http) gt 0
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020012399 tcp-request content track-sc1 src
Willy Tarreaue9656522010-08-17 15:40:09 +020012400 tcp-request content reject if click_too_fast mark_as_abuser
Willy Tarreau62644772008-07-16 18:36:06 +020012401
Willy Tarreauc57f0e22009-05-10 13:12:33 +020012402 See section 7 about ACL usage.
Willy Tarreau62644772008-07-16 18:36:06 +020012403
Jarno Huuskonen95b012b2017-04-06 13:59:14 +030012404 See also : "tcp-request connection", "tcp-request session",
12405 "tcp-request inspect-delay", and "http-request".
Willy Tarreau62644772008-07-16 18:36:06 +020012406
12407
12408tcp-request inspect-delay <timeout>
12409 Set the maximum allowed time to wait for data during content inspection
12410 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaufb356202010-08-03 14:02:05 +020012411 no | yes | yes | yes
Willy Tarreau62644772008-07-16 18:36:06 +020012412 Arguments :
12413 <timeout> is the timeout value specified in milliseconds by default, but
12414 can be in any other unit if the number is suffixed by the unit,
12415 as explained at the top of this document.
12416
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012417 People using HAProxy primarily as a TCP relay are often worried about the
Willy Tarreau62644772008-07-16 18:36:06 +020012418 risk of passing any type of protocol to a server without any analysis. In
12419 order to be able to analyze the request contents, we must first withhold
12420 the data then analyze them. This statement simply enables withholding of
12421 data for at most the specified amount of time.
12422
Willy Tarreaufb356202010-08-03 14:02:05 +020012423 TCP content inspection applies very early when a connection reaches a
12424 frontend, then very early when the connection is forwarded to a backend. This
12425 means that a connection may experience a first delay in the frontend and a
12426 second delay in the backend if both have tcp-request rules.
12427
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012428 Note that when performing content inspection, HAProxy will evaluate the whole
Willy Tarreau62644772008-07-16 18:36:06 +020012429 rules for every new chunk which gets in, taking into account the fact that
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010012430 those data are partial. If no rule matches before the aforementioned delay,
Willy Tarreau62644772008-07-16 18:36:06 +020012431 a last check is performed upon expiration, this time considering that the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012432 contents are definitive. If no delay is set, HAProxy will not wait at all
Willy Tarreaud869b242009-03-15 14:43:58 +010012433 and will immediately apply a verdict based on the available information.
12434 Obviously this is unlikely to be very useful and might even be racy, so such
12435 setups are not recommended.
Willy Tarreau62644772008-07-16 18:36:06 +020012436
12437 As soon as a rule matches, the request is released and continues as usual. If
12438 the timeout is reached and no rule matches, the default policy will be to let
12439 it pass through unaffected.
12440
12441 For most protocols, it is enough to set it to a few seconds, as most clients
12442 send the full request immediately upon connection. Add 3 or more seconds to
12443 cover TCP retransmits but that's all. For some protocols, it may make sense
Willy Tarreaud72758d2010-01-12 10:42:19 +010012444 to use large values, for instance to ensure that the client never talks
Davor Ocelice9ed2812017-12-25 17:49:28 +010012445 before the server (e.g. SMTP), or to wait for a client to talk before passing
12446 data to the server (e.g. SSL). Note that the client timeout must cover at
Willy Tarreaub824b002010-09-29 16:36:16 +020012447 least the inspection delay, otherwise it will expire first. If the client
12448 closes the connection or if the buffer is full, the delay immediately expires
12449 since the contents will not be able to change anymore.
Willy Tarreau62644772008-07-16 18:36:06 +020012450
Willy Tarreau55165fe2009-05-10 12:02:55 +020012451 See also : "tcp-request content accept", "tcp-request content reject",
Willy Tarreau62644772008-07-16 18:36:06 +020012452 "timeout client".
12453
12454
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012455tcp-response content <action> [{if | unless} <condition>]
12456 Perform an action on a session response depending on a layer 4-7 condition
12457 May be used in sections : defaults | frontend | listen | backend
12458 no | no | yes | yes
12459 Arguments :
Willy Tarreauc870bfd2015-09-28 18:47:38 +020012460 <action> defines the action to perform if the condition applies. See
12461 below.
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012462
12463 <condition> is a standard layer 4-7 ACL-based condition (see section 7).
12464
Davor Ocelice9ed2812017-12-25 17:49:28 +010012465 Response contents can be analyzed at an early stage of response processing
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012466 called "TCP content inspection". During this stage, ACL-based rules are
12467 evaluated every time the response contents are updated, until either an
Willy Tarreaucc1e04b2013-09-11 23:20:29 +020012468 "accept", "close" or a "reject" rule matches, or a TCP response inspection
12469 delay is set and expires with no matching rule.
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012470
12471 Most often, these decisions will consider a protocol recognition or validity.
12472
12473 Content-based rules are evaluated in their exact declaration order. If no
12474 rule matches or if there is no rule, the default action is to accept the
12475 contents. There is no specific limit to the number of rules which may be
12476 inserted.
12477
Thierry FOURNIER236657b2015-08-19 08:25:14 +020012478 Several types of actions are supported :
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012479 - accept :
12480 accepts the response if the condition is true (when used with "if")
12481 or false (when used with "unless"). The first such rule executed ends
12482 the rules evaluation.
12483
Willy Tarreaucc1e04b2013-09-11 23:20:29 +020012484 - close :
12485 immediately closes the connection with the server if the condition is
12486 true (when used with "if"), or false (when used with "unless"). The
12487 first such rule executed ends the rules evaluation. The main purpose of
12488 this action is to force a connection to be finished between a client
12489 and a server after an exchange when the application protocol expects
12490 some long time outs to elapse first. The goal is to eliminate idle
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030012491 connections which take significant resources on servers with certain
Willy Tarreaucc1e04b2013-09-11 23:20:29 +020012492 protocols.
12493
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012494 - reject :
12495 rejects the response if the condition is true (when used with "if")
12496 or false (when used with "unless"). The first such rule executed ends
Jamie Gloudonaaa21002012-08-25 00:18:33 -040012497 the rules evaluation. Rejected session are immediately closed.
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012498
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012499 - set-var(<var-name>) <expr>
Willy Tarreau9de54ba2021-09-02 20:51:21 +020012500 Sets a variable from an expression.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012501
Christopher Faulet85d79c92016-11-09 16:54:56 +010012502 - unset-var(<var-name>)
12503 Unsets a variable.
12504
Thierry FOURNIERe0627bd2015-08-04 08:20:33 +020012505 - sc-inc-gpc0(<sc-id>):
12506 This action increments the GPC0 counter according to the sticky
12507 counter designated by <sc-id>. If an error occurs, this action fails
12508 silently and the actions evaluation continues.
12509
Frédéric Lécaille6778b272018-01-29 15:22:53 +010012510 - sc-inc-gpc1(<sc-id>):
12511 This action increments the GPC1 counter according to the sticky
12512 counter designated by <sc-id>. If an error occurs, this action fails
12513 silently and the actions evaluation continues.
12514
Cédric Dufour0d7712d2019-11-06 18:38:53 +010012515 - sc-set-gpt0(<sc-id>) { <int> | <expr> }
12516 This action sets the 32-bit unsigned GPT0 tag according to the sticky
12517 counter designated by <sc-id> and the value of <int>/<expr>. The
12518 expected result is a boolean. If an error occurs, this action silently
12519 fails and the actions evaluation continues.
Thierry FOURNIER236657b2015-08-19 08:25:14 +020012520
Willy Tarreau2d392c22015-08-24 01:43:45 +020012521 - "silent-drop" :
12522 This stops the evaluation of the rules and makes the client-facing
Davor Ocelice9ed2812017-12-25 17:49:28 +010012523 connection suddenly disappear using a system-dependent way that tries
Willy Tarreau2d392c22015-08-24 01:43:45 +020012524 to prevent the client from being notified. The effect it then that the
12525 client still sees an established connection while there's none on
12526 HAProxy. The purpose is to achieve a comparable effect to "tarpit"
12527 except that it doesn't use any local resource at all on the machine
12528 running HAProxy. It can resist much higher loads than "tarpit", and
Davor Ocelice9ed2812017-12-25 17:49:28 +010012529 slow down stronger attackers. It is important to understand the impact
12530 of using this mechanism. All stateful equipment placed between the
Willy Tarreau2d392c22015-08-24 01:43:45 +020012531 client and HAProxy (firewalls, proxies, load balancers) will also keep
12532 the established connection for a long time and may suffer from this
Davor Ocelice9ed2812017-12-25 17:49:28 +010012533 action. On modern Linux systems running with enough privileges, the
Willy Tarreau2d392c22015-08-24 01:43:45 +020012534 TCP_REPAIR socket option is used to block the emission of a TCP
12535 reset. On other systems, the socket's TTL is reduced to 1 so that the
12536 TCP reset doesn't pass the first router, though it's still delivered to
12537 local networks. Do not use it unless you fully understand how it works.
12538
Christopher Faulet76c09ef2017-09-21 11:03:52 +020012539 - send-spoe-group <engine-name> <group-name>
12540 Send a group of SPOE messages.
12541
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012542 Note that the "if/unless" condition is optional. If no condition is set on
12543 the action, it is simply performed unconditionally. That can be useful for
12544 for changing the default action to a reject.
12545
Jamie Gloudonaaa21002012-08-25 00:18:33 -040012546 It is perfectly possible to match layer 7 contents with "tcp-response
12547 content" rules, but then it is important to ensure that a full response has
12548 been buffered, otherwise no contents will match. In order to achieve this,
12549 the best solution involves detecting the HTTP protocol during the inspection
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012550 period.
12551
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012552 The "set-var" is used to set the content of a variable. The variable is
12553 declared inline.
12554
Daniel Schneller0b547052016-03-21 20:46:57 +010012555 <var-name> The name of the variable starts with an indication about
12556 its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010012557 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010012558 "sess" : the variable is shared with the whole session
12559 "txn" : the variable is shared with the transaction
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012560 (request and response)
Daniel Schneller0b547052016-03-21 20:46:57 +010012561 "req" : the variable is shared only during request
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012562 processing
Daniel Schneller0b547052016-03-21 20:46:57 +010012563 "res" : the variable is shared only during response
12564 processing
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012565 This prefix is followed by a name. The separator is a '.'.
Christopher Fauletb71557a2016-10-31 10:49:03 +010012566 The name may only contain characters 'a-z', 'A-Z', '0-9',
12567 '.' and '_'.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020012568
12569 <expr> Is a standard HAProxy expression formed by a sample-fetch
12570 followed by some converters.
12571
Christopher Faulet85d79c92016-11-09 16:54:56 +010012572 The "unset-var" is used to unset a variable. See above for details about
12573 <var-name>.
12574
Christopher Faulet76c09ef2017-09-21 11:03:52 +020012575 The "send-spoe-group" is used to trigger sending of a group of SPOE
12576 messages. To do so, the SPOE engine used to send messages must be defined, as
12577 well as the SPOE group to send. Of course, the SPOE engine must refer to an
12578 existing SPOE filter. If not engine name is provided on the SPOE filter line,
12579 the SPOE agent name must be used.
12580
12581 <engine-name> The SPOE engine name.
12582
12583 <group-name> The SPOE group name as specified in the engine configuration.
12584
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012585 See section 7 about ACL usage.
12586
12587 See also : "tcp-request content", "tcp-response inspect-delay"
12588
12589
Willy Tarreau4f614292016-10-21 17:49:36 +020012590tcp-request session <action> [{if | unless} <condition>]
12591 Perform an action on a validated session depending on a layer 5 condition
12592 May be used in sections : defaults | frontend | listen | backend
12593 no | yes | yes | no
12594 Arguments :
12595 <action> defines the action to perform if the condition applies. See
12596 below.
12597
12598 <condition> is a standard layer5-only ACL-based condition (see section 7).
12599
Davor Ocelice9ed2812017-12-25 17:49:28 +010012600 Once a session is validated, (i.e. after all handshakes have been completed),
Willy Tarreau4f614292016-10-21 17:49:36 +020012601 it is possible to evaluate some conditions to decide whether this session
12602 must be accepted or dropped or have its counters tracked. Those conditions
12603 cannot make use of any data contents because no buffers are allocated yet and
12604 the processing cannot wait at this stage. The main use case it to copy some
12605 early information into variables (since variables are accessible in the
12606 session), or to keep track of some information collected after the handshake,
12607 such as SSL-level elements (SNI, ciphers, client cert's CN) or information
Davor Ocelice9ed2812017-12-25 17:49:28 +010012608 from the PROXY protocol header (e.g. track a source forwarded this way). The
Willy Tarreau4f614292016-10-21 17:49:36 +020012609 extracted information can thus be copied to a variable or tracked using
12610 "track-sc" rules. Of course it is also possible to decide to accept/reject as
12611 with other rulesets. Most operations performed here could also be performed
12612 in "tcp-request content" rules, except that in HTTP these rules are evaluated
12613 for each new request, and that might not always be acceptable. For example a
12614 rule might increment a counter on each evaluation. It would also be possible
12615 that a country is resolved by geolocation from the source IP address,
12616 assigned to a session-wide variable, then the source address rewritten from
12617 an HTTP header for all requests. If some contents need to be inspected in
12618 order to take the decision, the "tcp-request content" statements must be used
12619 instead.
12620
12621 The "tcp-request session" rules are evaluated in their exact declaration
12622 order. If no rule matches or if there is no rule, the default action is to
12623 accept the incoming session. There is no specific limit to the number of
12624 rules which may be inserted.
12625
12626 Several types of actions are supported :
12627 - accept : the request is accepted
12628 - reject : the request is rejected and the connection is closed
12629 - { track-sc0 | track-sc1 | track-sc2 } <key> [table <table>]
12630 - sc-inc-gpc0(<sc-id>)
Frédéric Lécaille6778b272018-01-29 15:22:53 +010012631 - sc-inc-gpc1(<sc-id>)
Cédric Dufour0d7712d2019-11-06 18:38:53 +010012632 - sc-set-gpt0(<sc-id>) { <int> | <expr> }
Christopher Faulet57759f32021-06-23 12:19:25 +020012633 - set-dst <expr>
12634 - set-dst-port <expr>
12635 - set-src <expr>
12636 - set-src-port <expr>
Willy Tarreau4f614292016-10-21 17:49:36 +020012637 - set-var(<var-name>) <expr>
Christopher Faulet85d79c92016-11-09 16:54:56 +010012638 - unset-var(<var-name>)
Willy Tarreau4f614292016-10-21 17:49:36 +020012639 - silent-drop
12640
12641 These actions have the same meaning as their respective counter-parts in
12642 "tcp-request connection" and "tcp-request content", so please refer to these
12643 sections for a complete description.
12644
12645 Note that the "if/unless" condition is optional. If no condition is set on
12646 the action, it is simply performed unconditionally. That can be useful for
12647 "track-sc*" actions as well as for changing the default action to a reject.
12648
12649 Example: track the original source address by default, or the one advertised
12650 in the PROXY protocol header for connection coming from the local
12651 proxies. The first connection-level rule enables receipt of the
12652 PROXY protocol for these ones, the second rule tracks whatever
12653 address we decide to keep after optional decoding.
12654
12655 tcp-request connection expect-proxy layer4 if { src -f proxies.lst }
12656 tcp-request session track-sc0 src
12657
12658 Example: accept all sessions from white-listed hosts, reject too fast
12659 sessions without counting them, and track accepted sessions.
12660 This results in session rate being capped from abusive sources.
12661
12662 tcp-request session accept if { src -f /etc/haproxy/whitelist.lst }
12663 tcp-request session reject if { src_sess_rate gt 10 }
12664 tcp-request session track-sc0 src
12665
12666 Example: accept all sessions from white-listed hosts, count all other
12667 sessions and reject too fast ones. This results in abusive ones
12668 being blocked as long as they don't slow down.
12669
12670 tcp-request session accept if { src -f /etc/haproxy/whitelist.lst }
12671 tcp-request session track-sc0 src
12672 tcp-request session reject if { sc0_sess_rate gt 10 }
12673
12674 See section 7 about ACL usage.
12675
12676 See also : "tcp-request connection", "tcp-request content", "stick-table"
12677
12678
Emeric Brun0a3b67f2010-09-24 15:34:53 +020012679tcp-response inspect-delay <timeout>
12680 Set the maximum allowed time to wait for a response during content inspection
12681 May be used in sections : defaults | frontend | listen | backend
12682 no | no | yes | yes
12683 Arguments :
12684 <timeout> is the timeout value specified in milliseconds by default, but
12685 can be in any other unit if the number is suffixed by the unit,
12686 as explained at the top of this document.
12687
12688 See also : "tcp-response content", "tcp-request inspect-delay".
12689
12690
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012691timeout check <timeout>
12692 Set additional check timeout, but only after a connection has been already
12693 established.
12694
12695 May be used in sections: defaults | frontend | listen | backend
12696 yes | no | yes | yes
12697 Arguments:
12698 <timeout> is the timeout value specified in milliseconds by default, but
12699 can be in any other unit if the number is suffixed by the unit,
12700 as explained at the top of this document.
12701
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012702 If set, HAProxy uses min("timeout connect", "inter") as a connect timeout
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012703 for check and "timeout check" as an additional read timeout. The "min" is
Davor Ocelice9ed2812017-12-25 17:49:28 +010012704 used so that people running with *very* long "timeout connect" (e.g. those
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012705 who needed this due to the queue or tarpit) do not slow down their checks.
Willy Tarreaud7550a22010-02-10 05:10:19 +010012706 (Please also note that there is no valid reason to have such long connect
12707 timeouts, because "timeout queue" and "timeout tarpit" can always be used to
12708 avoid that).
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012709
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012710 If "timeout check" is not set HAProxy uses "inter" for complete check
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012711 timeout (connect + read) exactly like all <1.3.15 version.
12712
12713 In most cases check request is much simpler and faster to handle than normal
12714 requests and people may want to kick out laggy servers so this timeout should
Willy Tarreau41a340d2008-01-22 12:25:31 +010012715 be smaller than "timeout server".
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012716
12717 This parameter is specific to backends, but can be specified once for all in
12718 "defaults" sections. This is in fact one of the easiest solutions not to
12719 forget about it.
12720
Willy Tarreau41a340d2008-01-22 12:25:31 +010012721 See also: "timeout connect", "timeout queue", "timeout server",
12722 "timeout tarpit".
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012723
12724
Willy Tarreau0ba27502007-12-24 16:55:16 +010012725timeout client <timeout>
Willy Tarreau0ba27502007-12-24 16:55:16 +010012726 Set the maximum inactivity time on the client side.
12727 May be used in sections : defaults | frontend | listen | backend
12728 yes | yes | yes | no
12729 Arguments :
Willy Tarreau844e3c52008-01-11 16:28:18 +010012730 <timeout> is the timeout value specified in milliseconds by default, but
Willy Tarreau0ba27502007-12-24 16:55:16 +010012731 can be in any other unit if the number is suffixed by the unit,
12732 as explained at the top of this document.
12733
12734 The inactivity timeout applies when the client is expected to acknowledge or
12735 send data. In HTTP mode, this timeout is particularly important to consider
12736 during the first phase, when the client sends the request, and during the
Baptiste Assmann2e1941e2016-03-06 23:24:12 +010012737 response while it is reading data sent by the server. That said, for the
12738 first phase, it is preferable to set the "timeout http-request" to better
12739 protect HAProxy from Slowloris like attacks. The value is specified in
12740 milliseconds by default, but can be in any other unit if the number is
Willy Tarreau0ba27502007-12-24 16:55:16 +010012741 suffixed by the unit, as specified at the top of this document. In TCP mode
12742 (and to a lesser extent, in HTTP mode), it is highly recommended that the
12743 client timeout remains equal to the server timeout in order to avoid complex
Willy Tarreaud2a4aa22008-01-31 15:28:22 +010012744 situations to debug. It is a good practice to cover one or several TCP packet
Willy Tarreau0ba27502007-12-24 16:55:16 +010012745 losses by specifying timeouts that are slightly above multiples of 3 seconds
Davor Ocelice9ed2812017-12-25 17:49:28 +010012746 (e.g. 4 or 5 seconds). If some long-lived sessions are mixed with short-lived
12747 sessions (e.g. WebSocket and HTTP), it's worth considering "timeout tunnel",
Willy Tarreau05cdd962014-05-10 14:30:07 +020012748 which overrides "timeout client" and "timeout server" for tunnels, as well as
12749 "timeout client-fin" for half-closed connections.
Willy Tarreau0ba27502007-12-24 16:55:16 +010012750
12751 This parameter is specific to frontends, but can be specified once for all in
12752 "defaults" sections. This is in fact one of the easiest solutions not to
12753 forget about it. An unspecified timeout results in an infinite timeout, which
12754 is not recommended. Such a usage is accepted and works but reports a warning
John Roeslerfb2fce12019-07-10 15:45:51 -050012755 during startup because it may result in accumulation of expired sessions in
Willy Tarreau0ba27502007-12-24 16:55:16 +010012756 the system if the system's timeouts are not configured either.
12757
Willy Tarreau95c4e142017-11-26 12:18:55 +010012758 This also applies to HTTP/2 connections, which will be closed with GOAWAY.
Lukas Tribus75df9d72017-11-24 19:05:12 +010012759
Tim Duesterhus86e6b6e2019-05-14 20:57:59 +020012760 See also : "timeout server", "timeout tunnel", "timeout http-request".
Willy Tarreau0ba27502007-12-24 16:55:16 +010012761
Willy Tarreau0ba27502007-12-24 16:55:16 +010012762
Willy Tarreau05cdd962014-05-10 14:30:07 +020012763timeout client-fin <timeout>
12764 Set the inactivity timeout on the client side for half-closed connections.
12765 May be used in sections : defaults | frontend | listen | backend
12766 yes | yes | yes | no
12767 Arguments :
12768 <timeout> is the timeout value specified in milliseconds by default, but
12769 can be in any other unit if the number is suffixed by the unit,
12770 as explained at the top of this document.
12771
12772 The inactivity timeout applies when the client is expected to acknowledge or
12773 send data while one direction is already shut down. This timeout is different
12774 from "timeout client" in that it only applies to connections which are closed
12775 in one direction. This is particularly useful to avoid keeping connections in
12776 FIN_WAIT state for too long when clients do not disconnect cleanly. This
12777 problem is particularly common long connections such as RDP or WebSocket.
12778 Note that this timeout can override "timeout tunnel" when a connection shuts
Willy Tarreau599391a2017-11-24 10:16:00 +010012779 down in one direction. It is applied to idle HTTP/2 connections once a GOAWAY
12780 frame was sent, often indicating an expectation that the connection quickly
12781 ends.
Willy Tarreau05cdd962014-05-10 14:30:07 +020012782
12783 This parameter is specific to frontends, but can be specified once for all in
12784 "defaults" sections. By default it is not set, so half-closed connections
12785 will use the other timeouts (timeout.client or timeout.tunnel).
12786
12787 See also : "timeout client", "timeout server-fin", and "timeout tunnel".
12788
12789
Willy Tarreau0ba27502007-12-24 16:55:16 +010012790timeout connect <timeout>
Willy Tarreau0ba27502007-12-24 16:55:16 +010012791 Set the maximum time to wait for a connection attempt to a server to succeed.
12792 May be used in sections : defaults | frontend | listen | backend
12793 yes | no | yes | yes
12794 Arguments :
Willy Tarreau844e3c52008-01-11 16:28:18 +010012795 <timeout> is the timeout value specified in milliseconds by default, but
Willy Tarreau0ba27502007-12-24 16:55:16 +010012796 can be in any other unit if the number is suffixed by the unit,
12797 as explained at the top of this document.
12798
Daniel Corbett9f0843f2021-05-08 10:50:37 -040012799 If the server is located on the same LAN as HAProxy, the connection should be
Willy Tarreaud2a4aa22008-01-31 15:28:22 +010012800 immediate (less than a few milliseconds). Anyway, it is a good practice to
Willy Tarreaud72758d2010-01-12 10:42:19 +010012801 cover one or several TCP packet losses by specifying timeouts that are
Davor Ocelice9ed2812017-12-25 17:49:28 +010012802 slightly above multiples of 3 seconds (e.g. 4 or 5 seconds). By default, the
Krzysztof Piotr Oledzki5259dfe2008-01-21 01:54:06 +010012803 connect timeout also presets both queue and tarpit timeouts to the same value
12804 if these have not been specified.
Willy Tarreau0ba27502007-12-24 16:55:16 +010012805
12806 This parameter is specific to backends, but can be specified once for all in
12807 "defaults" sections. This is in fact one of the easiest solutions not to
12808 forget about it. An unspecified timeout results in an infinite timeout, which
12809 is not recommended. Such a usage is accepted and works but reports a warning
John Roeslerfb2fce12019-07-10 15:45:51 -050012810 during startup because it may result in accumulation of failed sessions in
Willy Tarreau0ba27502007-12-24 16:55:16 +010012811 the system if the system's timeouts are not configured either.
12812
Tim Duesterhus86e6b6e2019-05-14 20:57:59 +020012813 See also: "timeout check", "timeout queue", "timeout server", "timeout tarpit".
Willy Tarreau0ba27502007-12-24 16:55:16 +010012814
Willy Tarreau0ba27502007-12-24 16:55:16 +010012815
Willy Tarreaub16a5742010-01-10 14:46:16 +010012816timeout http-keep-alive <timeout>
12817 Set the maximum allowed time to wait for a new HTTP request to appear
12818 May be used in sections : defaults | frontend | listen | backend
12819 yes | yes | yes | yes
12820 Arguments :
12821 <timeout> is the timeout value specified in milliseconds by default, but
12822 can be in any other unit if the number is suffixed by the unit,
12823 as explained at the top of this document.
12824
12825 By default, the time to wait for a new request in case of keep-alive is set
12826 by "timeout http-request". However this is not always convenient because some
12827 people want very short keep-alive timeouts in order to release connections
12828 faster, and others prefer to have larger ones but still have short timeouts
12829 once the request has started to present itself.
12830
12831 The "http-keep-alive" timeout covers these needs. It will define how long to
12832 wait for a new HTTP request to start coming after a response was sent. Once
12833 the first byte of request has been seen, the "http-request" timeout is used
12834 to wait for the complete request to come. Note that empty lines prior to a
12835 new request do not refresh the timeout and are not counted as a new request.
12836
12837 There is also another difference between the two timeouts : when a connection
12838 expires during timeout http-keep-alive, no error is returned, the connection
12839 just closes. If the connection expires in "http-request" while waiting for a
12840 connection to complete, a HTTP 408 error is returned.
12841
12842 In general it is optimal to set this value to a few tens to hundreds of
12843 milliseconds, to allow users to fetch all objects of a page at once but
Davor Ocelice9ed2812017-12-25 17:49:28 +010012844 without waiting for further clicks. Also, if set to a very small value (e.g.
Willy Tarreaub16a5742010-01-10 14:46:16 +010012845 1 millisecond) it will probably only accept pipelined requests but not the
12846 non-pipelined ones. It may be a nice trade-off for very large sites running
Patrick Mézard2382ad62010-05-09 10:43:32 +020012847 with tens to hundreds of thousands of clients.
Willy Tarreaub16a5742010-01-10 14:46:16 +010012848
12849 If this parameter is not set, the "http-request" timeout applies, and if both
12850 are not set, "timeout client" still applies at the lower level. It should be
12851 set in the frontend to take effect, unless the frontend is in TCP mode, in
12852 which case the HTTP backend's timeout will be used.
12853
Willy Tarreau95c4e142017-11-26 12:18:55 +010012854 When using HTTP/2 "timeout client" is applied instead. This is so we can keep
12855 using short keep-alive timeouts in HTTP/1.1 while using longer ones in HTTP/2
Lukas Tribus75df9d72017-11-24 19:05:12 +010012856 (where we only have one connection per client and a connection setup).
12857
Willy Tarreaub16a5742010-01-10 14:46:16 +010012858 See also : "timeout http-request", "timeout client".
12859
12860
Willy Tarreau036fae02008-01-06 13:24:40 +010012861timeout http-request <timeout>
12862 Set the maximum allowed time to wait for a complete HTTP request
12863 May be used in sections : defaults | frontend | listen | backend
Willy Tarreaucd7afc02009-07-12 10:03:17 +020012864 yes | yes | yes | yes
Willy Tarreau036fae02008-01-06 13:24:40 +010012865 Arguments :
Willy Tarreau844e3c52008-01-11 16:28:18 +010012866 <timeout> is the timeout value specified in milliseconds by default, but
Willy Tarreau036fae02008-01-06 13:24:40 +010012867 can be in any other unit if the number is suffixed by the unit,
12868 as explained at the top of this document.
12869
12870 In order to offer DoS protection, it may be required to lower the maximum
12871 accepted time to receive a complete HTTP request without affecting the client
12872 timeout. This helps protecting against established connections on which
12873 nothing is sent. The client timeout cannot offer a good protection against
12874 this abuse because it is an inactivity timeout, which means that if the
12875 attacker sends one character every now and then, the timeout will not
12876 trigger. With the HTTP request timeout, no matter what speed the client
Willy Tarreau2705a612014-05-23 17:38:34 +020012877 types, the request will be aborted if it does not complete in time. When the
12878 timeout expires, an HTTP 408 response is sent to the client to inform it
12879 about the problem, and the connection is closed. The logs will report
12880 termination codes "cR". Some recent browsers are having problems with this
Davor Ocelice9ed2812017-12-25 17:49:28 +010012881 standard, well-documented behavior, so it might be needed to hide the 408
Willy Tarreau0f228a02015-05-01 15:37:53 +020012882 code using "option http-ignore-probes" or "errorfile 408 /dev/null". See
12883 more details in the explanations of the "cR" termination code in section 8.5.
Willy Tarreau036fae02008-01-06 13:24:40 +010012884
Baptiste Assmanneccdf432015-10-28 13:49:01 +010012885 By default, this timeout only applies to the header part of the request,
12886 and not to any data. As soon as the empty line is received, this timeout is
12887 not used anymore. When combined with "option http-buffer-request", this
12888 timeout also applies to the body of the request..
12889 It is used again on keep-alive connections to wait for a second
Willy Tarreaub16a5742010-01-10 14:46:16 +010012890 request if "timeout http-keep-alive" is not set.
Willy Tarreau036fae02008-01-06 13:24:40 +010012891
12892 Generally it is enough to set it to a few seconds, as most clients send the
12893 full request immediately upon connection. Add 3 or more seconds to cover TCP
Davor Ocelice9ed2812017-12-25 17:49:28 +010012894 retransmits but that's all. Setting it to very low values (e.g. 50 ms) will
Willy Tarreau036fae02008-01-06 13:24:40 +010012895 generally work on local networks as long as there are no packet losses. This
12896 will prevent people from sending bare HTTP requests using telnet.
12897
12898 If this parameter is not set, the client timeout still applies between each
Willy Tarreaucd7afc02009-07-12 10:03:17 +020012899 chunk of the incoming request. It should be set in the frontend to take
12900 effect, unless the frontend is in TCP mode, in which case the HTTP backend's
12901 timeout will be used.
Willy Tarreau036fae02008-01-06 13:24:40 +010012902
Willy Tarreau0f228a02015-05-01 15:37:53 +020012903 See also : "errorfile", "http-ignore-probes", "timeout http-keep-alive", and
Baptiste Assmanneccdf432015-10-28 13:49:01 +010012904 "timeout client", "option http-buffer-request".
Willy Tarreau036fae02008-01-06 13:24:40 +010012905
Willy Tarreau844e3c52008-01-11 16:28:18 +010012906
12907timeout queue <timeout>
12908 Set the maximum time to wait in the queue for a connection slot to be free
12909 May be used in sections : defaults | frontend | listen | backend
12910 yes | no | yes | yes
12911 Arguments :
12912 <timeout> is the timeout value specified in milliseconds by default, but
12913 can be in any other unit if the number is suffixed by the unit,
12914 as explained at the top of this document.
12915
12916 When a server's maxconn is reached, connections are left pending in a queue
12917 which may be server-specific or global to the backend. In order not to wait
12918 indefinitely, a timeout is applied to requests pending in the queue. If the
12919 timeout is reached, it is considered that the request will almost never be
12920 served, so it is dropped and a 503 error is returned to the client.
12921
12922 The "timeout queue" statement allows to fix the maximum time for a request to
12923 be left pending in a queue. If unspecified, the same value as the backend's
12924 connection timeout ("timeout connect") is used, for backwards compatibility
12925 with older versions with no "timeout queue" parameter.
12926
Tim Duesterhus86e6b6e2019-05-14 20:57:59 +020012927 See also : "timeout connect".
Willy Tarreau844e3c52008-01-11 16:28:18 +010012928
12929
12930timeout server <timeout>
Willy Tarreau844e3c52008-01-11 16:28:18 +010012931 Set the maximum inactivity time on the server side.
12932 May be used in sections : defaults | frontend | listen | backend
12933 yes | no | yes | yes
12934 Arguments :
12935 <timeout> is the timeout value specified in milliseconds by default, but
12936 can be in any other unit if the number is suffixed by the unit,
12937 as explained at the top of this document.
12938
12939 The inactivity timeout applies when the server is expected to acknowledge or
12940 send data. In HTTP mode, this timeout is particularly important to consider
12941 during the first phase of the server's response, when it has to send the
12942 headers, as it directly represents the server's processing time for the
12943 request. To find out what value to put there, it's often good to start with
12944 what would be considered as unacceptable response times, then check the logs
12945 to observe the response time distribution, and adjust the value accordingly.
12946
12947 The value is specified in milliseconds by default, but can be in any other
12948 unit if the number is suffixed by the unit, as specified at the top of this
12949 document. In TCP mode (and to a lesser extent, in HTTP mode), it is highly
12950 recommended that the client timeout remains equal to the server timeout in
12951 order to avoid complex situations to debug. Whatever the expected server
Willy Tarreaud2a4aa22008-01-31 15:28:22 +010012952 response times, it is a good practice to cover at least one or several TCP
Willy Tarreau844e3c52008-01-11 16:28:18 +010012953 packet losses by specifying timeouts that are slightly above multiples of 3
Davor Ocelice9ed2812017-12-25 17:49:28 +010012954 seconds (e.g. 4 or 5 seconds minimum). If some long-lived sessions are mixed
12955 with short-lived sessions (e.g. WebSocket and HTTP), it's worth considering
Willy Tarreauce887fd2012-05-12 12:50:00 +020012956 "timeout tunnel", which overrides "timeout client" and "timeout server" for
12957 tunnels.
Willy Tarreau844e3c52008-01-11 16:28:18 +010012958
12959 This parameter is specific to backends, but can be specified once for all in
12960 "defaults" sections. This is in fact one of the easiest solutions not to
12961 forget about it. An unspecified timeout results in an infinite timeout, which
12962 is not recommended. Such a usage is accepted and works but reports a warning
John Roeslerfb2fce12019-07-10 15:45:51 -050012963 during startup because it may result in accumulation of expired sessions in
Willy Tarreau844e3c52008-01-11 16:28:18 +010012964 the system if the system's timeouts are not configured either.
12965
Tim Duesterhus86e6b6e2019-05-14 20:57:59 +020012966 See also : "timeout client" and "timeout tunnel".
Willy Tarreau844e3c52008-01-11 16:28:18 +010012967
Willy Tarreau05cdd962014-05-10 14:30:07 +020012968
12969timeout server-fin <timeout>
12970 Set the inactivity timeout on the server side for half-closed connections.
12971 May be used in sections : defaults | frontend | listen | backend
12972 yes | no | yes | yes
12973 Arguments :
12974 <timeout> is the timeout value specified in milliseconds by default, but
12975 can be in any other unit if the number is suffixed by the unit,
12976 as explained at the top of this document.
12977
12978 The inactivity timeout applies when the server is expected to acknowledge or
12979 send data while one direction is already shut down. This timeout is different
12980 from "timeout server" in that it only applies to connections which are closed
12981 in one direction. This is particularly useful to avoid keeping connections in
12982 FIN_WAIT state for too long when a remote server does not disconnect cleanly.
12983 This problem is particularly common long connections such as RDP or WebSocket.
12984 Note that this timeout can override "timeout tunnel" when a connection shuts
12985 down in one direction. This setting was provided for completeness, but in most
12986 situations, it should not be needed.
12987
12988 This parameter is specific to backends, but can be specified once for all in
12989 "defaults" sections. By default it is not set, so half-closed connections
12990 will use the other timeouts (timeout.server or timeout.tunnel).
12991
12992 See also : "timeout client-fin", "timeout server", and "timeout tunnel".
12993
Willy Tarreau844e3c52008-01-11 16:28:18 +010012994
12995timeout tarpit <timeout>
Cyril Bonté78caf842010-03-10 22:41:43 +010012996 Set the duration for which tarpitted connections will be maintained
Willy Tarreau844e3c52008-01-11 16:28:18 +010012997 May be used in sections : defaults | frontend | listen | backend
12998 yes | yes | yes | yes
12999 Arguments :
13000 <timeout> is the tarpit duration specified in milliseconds by default, but
13001 can be in any other unit if the number is suffixed by the unit,
13002 as explained at the top of this document.
13003
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020013004 When a connection is tarpitted using "http-request tarpit", it is maintained
13005 open with no activity for a certain amount of time, then closed. "timeout
13006 tarpit" defines how long it will be maintained open.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013007
13008 The value is specified in milliseconds by default, but can be in any other
13009 unit if the number is suffixed by the unit, as specified at the top of this
13010 document. If unspecified, the same value as the backend's connection timeout
13011 ("timeout connect") is used, for backwards compatibility with older versions
Cyril Bonté78caf842010-03-10 22:41:43 +010013012 with no "timeout tarpit" parameter.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013013
Tim Duesterhus86e6b6e2019-05-14 20:57:59 +020013014 See also : "timeout connect".
Willy Tarreau844e3c52008-01-11 16:28:18 +010013015
13016
Willy Tarreauce887fd2012-05-12 12:50:00 +020013017timeout tunnel <timeout>
13018 Set the maximum inactivity time on the client and server side for tunnels.
13019 May be used in sections : defaults | frontend | listen | backend
13020 yes | no | yes | yes
13021 Arguments :
13022 <timeout> is the timeout value specified in milliseconds by default, but
13023 can be in any other unit if the number is suffixed by the unit,
13024 as explained at the top of this document.
13025
Jamie Gloudonaaa21002012-08-25 00:18:33 -040013026 The tunnel timeout applies when a bidirectional connection is established
Willy Tarreauce887fd2012-05-12 12:50:00 +020013027 between a client and a server, and the connection remains inactive in both
13028 directions. This timeout supersedes both the client and server timeouts once
13029 the connection becomes a tunnel. In TCP, this timeout is used as soon as no
Davor Ocelice9ed2812017-12-25 17:49:28 +010013030 analyzer remains attached to either connection (e.g. tcp content rules are
13031 accepted). In HTTP, this timeout is used when a connection is upgraded (e.g.
Willy Tarreauce887fd2012-05-12 12:50:00 +020013032 when switching to the WebSocket protocol, or forwarding a CONNECT request
13033 to a proxy), or after the first response when no keepalive/close option is
13034 specified.
13035
Willy Tarreau05cdd962014-05-10 14:30:07 +020013036 Since this timeout is usually used in conjunction with long-lived connections,
13037 it usually is a good idea to also set "timeout client-fin" to handle the
13038 situation where a client suddenly disappears from the net and does not
13039 acknowledge a close, or sends a shutdown and does not acknowledge pending
13040 data anymore. This can happen in lossy networks where firewalls are present,
13041 and is detected by the presence of large amounts of sessions in a FIN_WAIT
13042 state.
13043
Willy Tarreauce887fd2012-05-12 12:50:00 +020013044 The value is specified in milliseconds by default, but can be in any other
13045 unit if the number is suffixed by the unit, as specified at the top of this
13046 document. Whatever the expected normal idle time, it is a good practice to
13047 cover at least one or several TCP packet losses by specifying timeouts that
Davor Ocelice9ed2812017-12-25 17:49:28 +010013048 are slightly above multiples of 3 seconds (e.g. 4 or 5 seconds minimum).
Willy Tarreauce887fd2012-05-12 12:50:00 +020013049
13050 This parameter is specific to backends, but can be specified once for all in
13051 "defaults" sections. This is in fact one of the easiest solutions not to
13052 forget about it.
13053
13054 Example :
13055 defaults http
13056 option http-server-close
13057 timeout connect 5s
13058 timeout client 30s
Willy Tarreau05cdd962014-05-10 14:30:07 +020013059 timeout client-fin 30s
Willy Tarreauce887fd2012-05-12 12:50:00 +020013060 timeout server 30s
13061 timeout tunnel 1h # timeout to use with WebSocket and CONNECT
13062
Willy Tarreau05cdd962014-05-10 14:30:07 +020013063 See also : "timeout client", "timeout client-fin", "timeout server".
Willy Tarreauce887fd2012-05-12 12:50:00 +020013064
13065
Willy Tarreau844e3c52008-01-11 16:28:18 +010013066transparent (deprecated)
13067 Enable client-side transparent proxying
13068 May be used in sections : defaults | frontend | listen | backend
Willy Tarreau4b1f8592008-12-23 23:13:55 +010013069 yes | no | yes | yes
Willy Tarreau844e3c52008-01-11 16:28:18 +010013070 Arguments : none
13071
13072 This keyword was introduced in order to provide layer 7 persistence to layer
13073 3 load balancers. The idea is to use the OS's ability to redirect an incoming
13074 connection for a remote address to a local process (here HAProxy), and let
13075 this process know what address was initially requested. When this option is
13076 used, sessions without cookies will be forwarded to the original destination
13077 IP address of the incoming request (which should match that of another
13078 equipment), while requests with cookies will still be forwarded to the
13079 appropriate server.
13080
13081 The "transparent" keyword is deprecated, use "option transparent" instead.
13082
13083 Note that contrary to a common belief, this option does NOT make HAProxy
13084 present the client's IP to the server when establishing the connection.
13085
Willy Tarreau844e3c52008-01-11 16:28:18 +010013086 See also: "option transparent"
13087
William Lallemanda73203e2012-03-12 12:48:57 +010013088unique-id-format <string>
13089 Generate a unique ID for each request.
13090 May be used in sections : defaults | frontend | listen | backend
13091 yes | yes | yes | no
13092 Arguments :
13093 <string> is a log-format string.
13094
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013095 This keyword creates a ID for each request using the custom log format. A
13096 unique ID is useful to trace a request passing through many components of
13097 a complex infrastructure. The newly created ID may also be logged using the
13098 %ID tag the log-format string.
William Lallemanda73203e2012-03-12 12:48:57 +010013099
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013100 The format should be composed from elements that are guaranteed to be
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013101 unique when combined together. For instance, if multiple HAProxy instances
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013102 are involved, it might be important to include the node name. It is often
13103 needed to log the incoming connection's source and destination addresses
13104 and ports. Note that since multiple requests may be performed over the same
13105 connection, including a request counter may help differentiate them.
13106 Similarly, a timestamp may protect against a rollover of the counter.
13107 Logging the process ID will avoid collisions after a service restart.
William Lallemanda73203e2012-03-12 12:48:57 +010013108
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013109 It is recommended to use hexadecimal notation for many fields since it
13110 makes them more compact and saves space in logs.
William Lallemanda73203e2012-03-12 12:48:57 +010013111
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013112 Example:
William Lallemanda73203e2012-03-12 12:48:57 +010013113
Julien Vehentf21be322014-03-07 08:27:34 -050013114 unique-id-format %{+X}o\ %ci:%cp_%fi:%fp_%Ts_%rt:%pid
William Lallemanda73203e2012-03-12 12:48:57 +010013115
13116 will generate:
13117
13118 7F000001:8296_7F00001E:1F90_4F7B0A69_0003:790A
13119
13120 See also: "unique-id-header"
13121
13122unique-id-header <name>
13123 Add a unique ID header in the HTTP request.
13124 May be used in sections : defaults | frontend | listen | backend
13125 yes | yes | yes | no
13126 Arguments :
13127 <name> is the name of the header.
13128
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013129 Add a unique-id header in the HTTP request sent to the server, using the
13130 unique-id-format. It can't work if the unique-id-format doesn't exist.
William Lallemanda73203e2012-03-12 12:48:57 +010013131
Cyril Bonté108cf6e2012-04-21 23:30:29 +020013132 Example:
William Lallemanda73203e2012-03-12 12:48:57 +010013133
Julien Vehentf21be322014-03-07 08:27:34 -050013134 unique-id-format %{+X}o\ %ci:%cp_%fi:%fp_%Ts_%rt:%pid
William Lallemanda73203e2012-03-12 12:48:57 +010013135 unique-id-header X-Unique-ID
13136
13137 will generate:
13138
13139 X-Unique-ID: 7F000001:8296_7F00001E:1F90_4F7B0A69_0003:790A
13140
13141 See also: "unique-id-format"
Willy Tarreau844e3c52008-01-11 16:28:18 +010013142
Willy Tarreauf51658d2014-04-23 01:21:56 +020013143use_backend <backend> [{if | unless} <condition>]
Willy Tarreau1d0dfb12009-07-07 15:10:31 +020013144 Switch to a specific backend if/unless an ACL-based condition is matched.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013145 May be used in sections : defaults | frontend | listen | backend
13146 no | yes | yes | no
13147 Arguments :
Bertrand Jacquin702d44f2013-11-19 11:43:06 +010013148 <backend> is the name of a valid backend or "listen" section, or a
13149 "log-format" string resolving to a backend name.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013150
Willy Tarreauf51658d2014-04-23 01:21:56 +020013151 <condition> is a condition composed of ACLs, as described in section 7. If
13152 it is omitted, the rule is unconditionally applied.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013153
13154 When doing content-switching, connections arrive on a frontend and are then
13155 dispatched to various backends depending on a number of conditions. The
13156 relation between the conditions and the backends is described with the
Willy Tarreau1d0dfb12009-07-07 15:10:31 +020013157 "use_backend" keyword. While it is normally used with HTTP processing, it can
Davor Ocelice9ed2812017-12-25 17:49:28 +010013158 also be used in pure TCP, either without content using stateless ACLs (e.g.
Willy Tarreau1d0dfb12009-07-07 15:10:31 +020013159 source address validation) or combined with a "tcp-request" rule to wait for
13160 some payload.
Willy Tarreau844e3c52008-01-11 16:28:18 +010013161
13162 There may be as many "use_backend" rules as desired. All of these rules are
13163 evaluated in their declaration order, and the first one which matches will
13164 assign the backend.
13165
13166 In the first form, the backend will be used if the condition is met. In the
13167 second form, the backend will be used if the condition is not met. If no
13168 condition is valid, the backend defined with "default_backend" will be used.
13169 If no default backend is defined, either the servers in the same section are
13170 used (in case of a "listen" section) or, in case of a frontend, no server is
13171 used and a 503 service unavailable response is returned.
13172
Willy Tarreau51aecc72009-07-12 09:47:04 +020013173 Note that it is possible to switch from a TCP frontend to an HTTP backend. In
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010013174 this case, either the frontend has already checked that the protocol is HTTP,
Willy Tarreau51aecc72009-07-12 09:47:04 +020013175 and backend processing will immediately follow, or the backend will wait for
13176 a complete HTTP request to get in. This feature is useful when a frontend
13177 must decode several protocols on a unique port, one of them being HTTP.
13178
Bertrand Jacquin702d44f2013-11-19 11:43:06 +010013179 When <backend> is a simple name, it is resolved at configuration time, and an
13180 error is reported if the specified backend does not exist. If <backend> is
13181 a log-format string instead, no check may be done at configuration time, so
13182 the backend name is resolved dynamically at run time. If the resulting
13183 backend name does not correspond to any valid backend, no other rule is
13184 evaluated, and the default_backend directive is applied instead. Note that
13185 when using dynamic backend names, it is highly recommended to use a prefix
13186 that no other backend uses in order to ensure that an unauthorized backend
13187 cannot be forced from the request.
13188
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013189 It is worth mentioning that "use_backend" rules with an explicit name are
Bertrand Jacquin702d44f2013-11-19 11:43:06 +010013190 used to detect the association between frontends and backends to compute the
13191 backend's "fullconn" setting. This cannot be done for dynamic names.
13192
13193 See also: "default_backend", "tcp-request", "fullconn", "log-format", and
13194 section 7 about ACLs.
Willy Tarreaud72758d2010-01-12 10:42:19 +010013195
Christopher Fauletb30b3102019-09-12 23:03:09 +020013196use-fcgi-app <name>
13197 Defines the FastCGI application to use for the backend.
13198 May be used in sections : defaults | frontend | listen | backend
13199 no | no | yes | yes
13200 Arguments :
13201 <name> is the name of the FastCGI application to use.
13202
13203 See section 10.1 about FastCGI application setup for details.
Willy Tarreau036fae02008-01-06 13:24:40 +010013204
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013205use-server <server> if <condition>
13206use-server <server> unless <condition>
13207 Only use a specific server if/unless an ACL-based condition is matched.
13208 May be used in sections : defaults | frontend | listen | backend
13209 no | no | yes | yes
13210 Arguments :
Jerome Magnin824186b2020-03-29 09:37:12 +020013211 <server> is the name of a valid server in the same backend section
13212 or a "log-format" string resolving to a server name.
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013213
13214 <condition> is a condition composed of ACLs, as described in section 7.
13215
13216 By default, connections which arrive to a backend are load-balanced across
13217 the available servers according to the configured algorithm, unless a
13218 persistence mechanism such as a cookie is used and found in the request.
13219
13220 Sometimes it is desirable to forward a particular request to a specific
13221 server without having to declare a dedicated backend for this server. This
13222 can be achieved using the "use-server" rules. These rules are evaluated after
13223 the "redirect" rules and before evaluating cookies, and they have precedence
13224 on them. There may be as many "use-server" rules as desired. All of these
13225 rules are evaluated in their declaration order, and the first one which
13226 matches will assign the server.
13227
13228 If a rule designates a server which is down, and "option persist" is not used
13229 and no force-persist rule was validated, it is ignored and evaluation goes on
13230 with the next rules until one matches.
13231
13232 In the first form, the server will be used if the condition is met. In the
13233 second form, the server will be used if the condition is not met. If no
13234 condition is valid, the processing continues and the server will be assigned
13235 according to other persistence mechanisms.
13236
13237 Note that even if a rule is matched, cookie processing is still performed but
13238 does not assign the server. This allows prefixed cookies to have their prefix
13239 stripped.
13240
13241 The "use-server" statement works both in HTTP and TCP mode. This makes it
13242 suitable for use with content-based inspection. For instance, a server could
Lukas Tribusa267b5d2020-07-19 00:25:06 +020013243 be selected in a farm according to the TLS SNI field when using protocols with
Alex18c88772021-06-05 13:23:08 +020013244 implicit TLS (also see "req.ssl_sni"). And if these servers have their weight
Lukas Tribusa267b5d2020-07-19 00:25:06 +020013245 set to zero, they will not be used for other traffic.
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013246
13247 Example :
13248 # intercept incoming TLS requests based on the SNI field
Alex18c88772021-06-05 13:23:08 +020013249 use-server www if { req.ssl_sni -i www.example.com }
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013250 server www 192.168.0.1:443 weight 0
Alex18c88772021-06-05 13:23:08 +020013251 use-server mail if { req.ssl_sni -i mail.example.com }
Lukas Tribusa267b5d2020-07-19 00:25:06 +020013252 server mail 192.168.0.1:465 weight 0
Alex18c88772021-06-05 13:23:08 +020013253 use-server imap if { req.ssl_sni -i imap.example.com }
Lukas Tribus98a3e3f2017-03-26 12:55:35 +000013254 server imap 192.168.0.1:993 weight 0
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013255 # all the rest is forwarded to this server
13256 server default 192.168.0.2:443 check
13257
Jerome Magnin824186b2020-03-29 09:37:12 +020013258 When <server> is a simple name, it is checked against existing servers in the
13259 configuration and an error is reported if the specified server does not exist.
13260 If it is a log-format, no check is performed when parsing the configuration,
13261 and if we can't resolve a valid server name at runtime but the use-server rule
Ilya Shipitsin11057a32020-06-21 21:18:27 +050013262 was conditioned by an ACL returning true, no other use-server rule is applied
Jerome Magnin824186b2020-03-29 09:37:12 +020013263 and we fall back to load balancing.
13264
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013265 See also: "use_backend", section 5 about server and section 7 about ACLs.
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013266
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013267
Davor Ocelice9ed2812017-12-25 17:49:28 +0100132685. Bind and server options
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013269--------------------------
13270
13271The "bind", "server" and "default-server" keywords support a number of settings
13272depending on some build options and on the system HAProxy was built on. These
13273settings generally each consist in one word sometimes followed by a value,
13274written on the same line as the "bind" or "server" line. All these options are
13275described in this section.
13276
13277
132785.1. Bind options
13279-----------------
13280
13281The "bind" keyword supports a certain number of settings which are all passed
13282as arguments on the same line. The order in which those arguments appear makes
13283no importance, provided that they appear after the bind address. All of these
13284parameters are optional. Some of them consist in a single words (booleans),
13285while other ones expect a value after them. In this case, the value must be
13286provided immediately after the setting name.
13287
13288The currently supported settings are the following ones.
13289
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010013290accept-netscaler-cip <magic number>
13291 Enforces the use of the NetScaler Client IP insertion protocol over any
13292 connection accepted by any of the TCP sockets declared on the same line. The
13293 NetScaler Client IP insertion protocol dictates the layer 3/4 addresses of
13294 the incoming connection to be used everywhere an address is used, with the
13295 only exception of "tcp-request connection" rules which will only see the
13296 real connection address. Logs will reflect the addresses indicated in the
13297 protocol, unless it is violated, in which case the real address will still
13298 be used. This keyword combined with support from external components can be
13299 used as an efficient and reliable alternative to the X-Forwarded-For
Bertrand Jacquin90759682016-06-06 15:35:39 +010013300 mechanism which is not always reliable and not even always usable. See also
13301 "tcp-request connection expect-netscaler-cip" for a finer-grained setting of
13302 which client is allowed to use the protocol.
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010013303
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013304accept-proxy
13305 Enforces the use of the PROXY protocol over any connection accepted by any of
Willy Tarreau77992672014-06-14 11:06:17 +020013306 the sockets declared on the same line. Versions 1 and 2 of the PROXY protocol
13307 are supported and correctly detected. The PROXY protocol dictates the layer
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013308 3/4 addresses of the incoming connection to be used everywhere an address is
13309 used, with the only exception of "tcp-request connection" rules which will
13310 only see the real connection address. Logs will reflect the addresses
13311 indicated in the protocol, unless it is violated, in which case the real
Davor Ocelice9ed2812017-12-25 17:49:28 +010013312 address will still be used. This keyword combined with support from external
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013313 components can be used as an efficient and reliable alternative to the
13314 X-Forwarded-For mechanism which is not always reliable and not even always
Willy Tarreau4f0d9192013-06-11 20:40:55 +020013315 usable. See also "tcp-request connection expect-proxy" for a finer-grained
13316 setting of which client is allowed to use the protocol.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013317
Olivier Houchardc2aae742017-09-22 18:26:28 +020013318allow-0rtt
Bertrand Jacquina25282b2018-08-14 00:56:13 +010013319 Allow receiving early data when using TLSv1.3. This is disabled by default,
Olivier Houchard69752962019-01-08 15:35:32 +010013320 due to security considerations. Because it is vulnerable to replay attacks,
John Roeslerfb2fce12019-07-10 15:45:51 -050013321 you should only allow if for requests that are safe to replay, i.e. requests
Olivier Houchard69752962019-01-08 15:35:32 +010013322 that are idempotent. You can use the "wait-for-handshake" action for any
13323 request that wouldn't be safe with early data.
Olivier Houchardc2aae742017-09-22 18:26:28 +020013324
Willy Tarreauab861d32013-04-02 02:30:41 +020013325alpn <protocols>
13326 This enables the TLS ALPN extension and advertises the specified protocol
13327 list as supported on top of ALPN. The protocol list consists in a comma-
13328 delimited list of protocol names, for instance: "http/1.1,http/1.0" (without
John Roeslerfb2fce12019-07-10 15:45:51 -050013329 quotes). This requires that the SSL library is built with support for TLS
Willy Tarreauab861d32013-04-02 02:30:41 +020013330 extensions enabled (check with haproxy -vv). The ALPN extension replaces the
Willy Tarreau95c4e142017-11-26 12:18:55 +010013331 initial NPN extension. ALPN is required to enable HTTP/2 on an HTTP frontend.
13332 Versions of OpenSSL prior to 1.0.2 didn't support ALPN and only supposed the
13333 now obsolete NPN extension. At the time of writing this, most browsers still
13334 support both ALPN and NPN for HTTP/2 so a fallback to NPN may still work for
13335 a while. But ALPN must be used whenever possible. If both HTTP/2 and HTTP/1.1
13336 are expected to be supported, both versions can be advertised, in order of
13337 preference, like below :
13338
13339 bind :443 ssl crt pub.pem alpn h2,http/1.1
Willy Tarreauab861d32013-04-02 02:30:41 +020013340
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013341backlog <backlog>
Willy Tarreaue2711c72019-02-27 15:39:41 +010013342 Sets the socket's backlog to this value. If unspecified or 0, the frontend's
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013343 backlog is used instead, which generally defaults to the maxconn value.
13344
Emmanuel Hocdete7f2b732017-01-09 16:15:54 +010013345curves <curves>
13346 This setting is only available when support for OpenSSL was built in. It sets
13347 the string describing the list of elliptic curves algorithms ("curve suite")
13348 that are negotiated during the SSL/TLS handshake with ECDHE. The format of the
13349 string is a colon-delimited list of curve name.
13350 Example: "X25519:P-256" (without quote)
13351 When "curves" is set, "ecdhe" parameter is ignored.
13352
Emeric Brun7fb34422012-09-28 15:26:15 +020013353ecdhe <named curve>
13354 This setting is only available when support for OpenSSL was built in. It sets
Emeric Brun6924ef82013-03-06 14:08:53 +010013355 the named curve (RFC 4492) used to generate ECDH ephemeral keys. By default,
13356 used named curve is prime256v1.
Emeric Brun7fb34422012-09-28 15:26:15 +020013357
Emeric Brunfd33a262012-10-11 16:28:27 +020013358ca-file <cafile>
Emeric Brun1a073b42012-09-28 17:07:34 +020013359 This setting is only available when support for OpenSSL was built in. It
13360 designates a PEM file from which to load CA certificates used to verify
13361 client's certificate.
13362
Emeric Brunb6dc9342012-09-28 17:55:37 +020013363ca-ignore-err [all|<errorID>,...]
13364 This setting is only available when support for OpenSSL was built in.
13365 Sets a comma separated list of errorIDs to ignore during verify at depth > 0.
13366 If set to 'all', all errors are ignored. SSL handshake is not aborted if an
13367 error is ignored.
13368
Christopher Faulet31af49d2015-06-09 17:29:50 +020013369ca-sign-file <cafile>
13370 This setting is only available when support for OpenSSL was built in. It
13371 designates a PEM file containing both the CA certificate and the CA private
13372 key used to create and sign server's certificates. This is a mandatory
13373 setting when the dynamic generation of certificates is enabled. See
13374 'generate-certificates' for details.
13375
Bertrand Jacquind4d0a232016-11-13 16:37:12 +000013376ca-sign-pass <passphrase>
Christopher Faulet31af49d2015-06-09 17:29:50 +020013377 This setting is only available when support for OpenSSL was built in. It is
13378 the CA private key passphrase. This setting is optional and used only when
13379 the dynamic generation of certificates is enabled. See
13380 'generate-certificates' for details.
13381
Emmanuel Hocdet842e94e2019-12-16 16:39:17 +010013382ca-verify-file <cafile>
13383 This setting designates a PEM file from which to load CA certificates used to
13384 verify client's certificate. It designates CA certificates which must not be
13385 included in CA names sent in server hello message. Typically, "ca-file" must
13386 be defined with intermediate certificates, and "ca-verify-file" with
13387 certificates to ending the chain, like root CA.
13388
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013389ciphers <ciphers>
13390 This setting is only available when support for OpenSSL was built in. It sets
13391 the string describing the list of cipher algorithms ("cipher suite") that are
Bertrand Jacquin8cf7c1e2019-02-03 18:35:25 +000013392 negotiated during the SSL/TLS handshake up to TLSv1.2. The format of the
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +000013393 string is defined in "man 1 ciphers" from OpenSSL man pages. For background
Dirkjan Bussink415150f2018-09-14 11:14:21 +020013394 information and recommendations see e.g.
13395 (https://wiki.mozilla.org/Security/Server_Side_TLS) and
13396 (https://mozilla.github.io/server-side-tls/ssl-config-generator/). For TLSv1.3
13397 cipher configuration, please check the "ciphersuites" keyword.
13398
13399ciphersuites <ciphersuites>
13400 This setting is only available when support for OpenSSL was built in and
13401 OpenSSL 1.1.1 or later was used to build HAProxy. It sets the string describing
13402 the list of cipher algorithms ("cipher suite") that are negotiated during the
13403 TLSv1.3 handshake. The format of the string is defined in "man 1 ciphers" from
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +000013404 OpenSSL man pages under the "ciphersuites" section. For cipher configuration
13405 for TLSv1.2 and earlier, please check the "ciphers" keyword.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013406
Emeric Brunfd33a262012-10-11 16:28:27 +020013407crl-file <crlfile>
Emeric Brun1a073b42012-09-28 17:07:34 +020013408 This setting is only available when support for OpenSSL was built in. It
13409 designates a PEM file from which to load certificate revocation list used
Remi Tricot-Le Breton02bd6842021-05-04 12:22:34 +020013410 to verify client's certificate. You need to provide a certificate revocation
13411 list for every certificate of your certificate authority chain.
Emeric Brun1a073b42012-09-28 17:07:34 +020013412
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013413crt <cert>
Alex Davies0fbf0162013-03-02 16:04:50 +000013414 This setting is only available when support for OpenSSL was built in. It
13415 designates a PEM file containing both the required certificates and any
13416 associated private keys. This file can be built by concatenating multiple
13417 PEM files into one (e.g. cat cert.pem key.pem > combined.pem). If your CA
13418 requires an intermediate certificate, this can also be concatenated into this
Emmanuel Hocdet70df7bf2019-01-04 11:08:20 +010013419 file. Intermediate certificate can also be shared in a directory via
13420 "issuers-chain-path" directive.
Alex Davies0fbf0162013-03-02 16:04:50 +000013421
William Lallemand4c5adbf2020-02-24 14:23:22 +010013422 If the file does not contain a private key, HAProxy will try to load
13423 the key at the same path suffixed by a ".key".
13424
Alex Davies0fbf0162013-03-02 16:04:50 +000013425 If the OpenSSL used supports Diffie-Hellman, parameters present in this file
13426 are loaded.
13427
13428 If a directory name is used instead of a PEM file, then all files found in
William Lallemand3f25ae32020-02-24 16:30:12 +010013429 that directory will be loaded in alphabetic order unless their name ends
13430 with '.key', '.issuer', '.ocsp' or '.sctl' (reserved extensions). This
13431 directive may be specified multiple times in order to load certificates from
13432 multiple files or directories. The certificates will be presented to clients
13433 who provide a valid TLS Server Name Indication field matching one of their
13434 CN or alt subjects. Wildcards are supported, where a wildcard character '*'
13435 is used instead of the first hostname component (e.g. *.example.org matches
Janusz Dziemidowicz2c701b52015-03-07 23:03:59 +010013436 www.example.org but not www.sub.example.org).
Alex Davies0fbf0162013-03-02 16:04:50 +000013437
13438 If no SNI is provided by the client or if the SSL library does not support
13439 TLS extensions, or if the client provides an SNI hostname which does not
13440 match any certificate, then the first loaded certificate will be presented.
13441 This means that when loading certificates from a directory, it is highly
Cyril Bonté3180f7b2015-01-25 00:16:08 +010013442 recommended to load the default one first as a file or to ensure that it will
13443 always be the first one in the directory.
Alex Davies0fbf0162013-03-02 16:04:50 +000013444
Emeric Brune032bfa2012-09-28 13:01:45 +020013445 Note that the same cert may be loaded multiple times without side effects.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013446
Davor Ocelice9ed2812017-12-25 17:49:28 +010013447 Some CAs (such as GoDaddy) offer a drop down list of server types that do not
Alex Davies0fbf0162013-03-02 16:04:50 +000013448 include HAProxy when obtaining a certificate. If this happens be sure to
Davor Ocelice9ed2812017-12-25 17:49:28 +010013449 choose a web server that the CA believes requires an intermediate CA (for
13450 GoDaddy, selection Apache Tomcat will get the correct bundle, but many
Alex Davies0fbf0162013-03-02 16:04:50 +000013451 others, e.g. nginx, result in a wrong bundle that will not work for some
13452 clients).
13453
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013454 For each PEM file, HAProxy checks for the presence of file at the same path
Emeric Brun4147b2e2014-06-16 18:36:30 +020013455 suffixed by ".ocsp". If such file is found, support for the TLS Certificate
13456 Status Request extension (also known as "OCSP stapling") is automatically
13457 enabled. The content of this file is optional. If not empty, it must contain
13458 a valid OCSP Response in DER format. In order to be valid an OCSP Response
13459 must comply with the following rules: it has to indicate a good status,
13460 it has to be a single response for the certificate of the PEM file, and it
13461 has to be valid at the moment of addition. If these rules are not respected
13462 the OCSP Response is ignored and a warning is emitted. In order to identify
13463 which certificate an OCSP Response applies to, the issuer's certificate is
13464 necessary. If the issuer's certificate is not found in the PEM file, it will
13465 be loaded from a file at the same path as the PEM file suffixed by ".issuer"
13466 if it exists otherwise it will fail with an error.
13467
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013468 For each PEM file, HAProxy also checks for the presence of file at the same
Janusz Dziemidowicz2c701b52015-03-07 23:03:59 +010013469 path suffixed by ".sctl". If such file is found, support for Certificate
13470 Transparency (RFC6962) TLS extension is enabled. The file must contain a
13471 valid Signed Certificate Timestamp List, as described in RFC. File is parsed
13472 to check basic syntax, but no signatures are verified.
13473
yanbzhu6c25e9e2016-01-05 12:52:02 -050013474 There are cases where it is desirable to support multiple key types, e.g. RSA
13475 and ECDSA in the cipher suites offered to the clients. This allows clients
13476 that support EC certificates to be able to use EC ciphers, while
13477 simultaneously supporting older, RSA only clients.
yanbzhud19630c2015-12-14 15:10:25 -050013478
William Lallemandf9ff3ec2020-10-02 17:57:44 +020013479 To achieve this, OpenSSL 1.1.1 is required, you can configure this behavior
13480 by providing one crt entry per certificate type, or by configuring a "cert
13481 bundle" like it was required before HAProxy 1.8. See "ssl-load-extra-files".
yanbzhud19630c2015-12-14 15:10:25 -050013482
Emeric Brunb6dc9342012-09-28 17:55:37 +020013483crt-ignore-err <errors>
Alex Davies0fbf0162013-03-02 16:04:50 +000013484 This setting is only available when support for OpenSSL was built in. Sets a
Davor Ocelice9ed2812017-12-25 17:49:28 +010013485 comma separated list of errorIDs to ignore during verify at depth == 0. If
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013486 set to 'all', all errors are ignored. SSL handshake is not aborted if an error
Alex Davies0fbf0162013-03-02 16:04:50 +000013487 is ignored.
Emeric Brunb6dc9342012-09-28 17:55:37 +020013488
Emmanuel Hocdetfe616562013-01-22 15:31:15 +010013489crt-list <file>
13490 This setting is only available when support for OpenSSL was built in. It
Emmanuel Hocdet98263292016-12-29 18:26:15 +010013491 designates a list of PEM file with an optional ssl configuration and a SNI
13492 filter per certificate, with the following format for each line :
Emmanuel Hocdetfe616562013-01-22 15:31:15 +010013493
Emmanuel Hocdet98263292016-12-29 18:26:15 +010013494 <crtfile> [\[<sslbindconf> ...\]] [[!]<snifilter> ...]
13495
William Lallemand5d036392020-06-30 16:11:36 +020013496 sslbindconf supports "allow-0rtt", "alpn", "ca-file", "ca-verify-file",
13497 "ciphers", "ciphersuites", "crl-file", "curves", "ecdhe", "no-ca-names",
13498 "npn", "verify" configuration. With BoringSSL and Openssl >= 1.1.1
13499 "ssl-min-ver" and "ssl-max-ver" are also supported. It overrides the
13500 configuration set in bind line for the certificate.
Emmanuel Hocdetfe616562013-01-22 15:31:15 +010013501
Emmanuel Hocdet7c41a1b2013-05-07 20:20:06 +020013502 Wildcards are supported in the SNI filter. Negative filter are also supported,
Joao Moraise51fab02020-11-21 07:42:20 -030013503 useful in combination with a wildcard filter to exclude a particular SNI, or
13504 after the first certificate to exclude a pattern from its CN or Subject Alt
13505 Name (SAN). The certificates will be presented to clients who provide a valid
13506 TLS Server Name Indication field matching one of the SNI filters. If no SNI
13507 filter is specified, the CN and SAN are used. This directive may be specified
Emmanuel Hocdet7c41a1b2013-05-07 20:20:06 +020013508 multiple times. See the "crt" option for more information. The default
13509 certificate is still needed to meet OpenSSL expectations. If it is not used,
13510 the 'strict-sni' option may be used.
Emmanuel Hocdetfe616562013-01-22 15:31:15 +010013511
William Lallemandf9ff3ec2020-10-02 17:57:44 +020013512 Multi-cert bundling (see "ssl-load-extra-files") is supported with crt-list,
13513 as long as only the base name is given in the crt-list. SNI filter will do
13514 the same work on all bundled certificates.
yanbzhud19630c2015-12-14 15:10:25 -050013515
William Lallemand7c26ed72020-06-03 17:34:48 +020013516 Empty lines as well as lines beginning with a hash ('#') will be ignored.
13517
Joao Moraisaa8fcc42020-11-24 08:24:30 -030013518 The first declared certificate of a bind line is used as the default
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013519 certificate, either from crt or crt-list option, which HAProxy should use in
Joao Moraisaa8fcc42020-11-24 08:24:30 -030013520 the TLS handshake if no other certificate matches. This certificate will also
13521 be used if the provided SNI matches its CN or SAN, even if a matching SNI
13522 filter is found on any crt-list. The SNI filter !* can be used after the first
13523 declared certificate to not include its CN and SAN in the SNI tree, so it will
13524 never match except if no other certificate matches. This way the first
13525 declared certificate act as a fallback.
Joao Moraise51fab02020-11-21 07:42:20 -030013526
Emmanuel Hocdet98263292016-12-29 18:26:15 +010013527 crt-list file example:
Joao Moraise51fab02020-11-21 07:42:20 -030013528 cert1.pem !*
William Lallemand7c26ed72020-06-03 17:34:48 +020013529 # comment
Emmanuel Hocdet05942112017-02-20 16:11:50 +010013530 cert2.pem [alpn h2,http/1.1]
Emmanuel Hocdet98263292016-12-29 18:26:15 +010013531 certW.pem *.domain.tld !secure.domain.tld
Emmanuel Hocdet05942112017-02-20 16:11:50 +010013532 certS.pem [curves X25519:P-256 ciphers ECDHE-ECDSA-AES256-GCM-SHA384] secure.domain.tld
Emmanuel Hocdet98263292016-12-29 18:26:15 +010013533
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013534defer-accept
13535 Is an optional keyword which is supported only on certain Linux kernels. It
13536 states that a connection will only be accepted once some data arrive on it,
13537 or at worst after the first retransmit. This should be used only on protocols
Davor Ocelice9ed2812017-12-25 17:49:28 +010013538 for which the client talks first (e.g. HTTP). It can slightly improve
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013539 performance by ensuring that most of the request is already available when
13540 the connection is accepted. On the other hand, it will not be able to detect
13541 connections which don't talk. It is important to note that this option is
13542 broken in all kernels up to 2.6.31, as the connection is never accepted until
13543 the client talks. This can cause issues with front firewalls which would see
13544 an established connection while the proxy will only see it in SYN_RECV. This
13545 option is only supported on TCPv4/TCPv6 sockets and ignored by other ones.
13546
William Lallemandf6975e92017-05-26 17:42:10 +020013547expose-fd listeners
13548 This option is only usable with the stats socket. It gives your stats socket
13549 the capability to pass listeners FD to another HAProxy process.
William Lallemande202b1e2017-06-01 17:38:56 +020013550 During a reload with the master-worker mode, the process is automatically
13551 reexecuted adding -x and one of the stats socket with this option.
Davor Ocelice9ed2812017-12-25 17:49:28 +010013552 See also "-x" in the management guide.
William Lallemandf6975e92017-05-26 17:42:10 +020013553
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013554force-sslv3
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013555 This option enforces use of SSLv3 only on SSL connections instantiated from
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013556 this listener. SSLv3 is generally less expensive than the TLS counterparts
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013557 for high connection rates. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013558 "ssl-default-bind-options". See also "ssl-min-ver" and "ssl-max-ver".
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013559
13560force-tlsv10
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013561 This option enforces use of TLSv1.0 only on SSL connections instantiated from
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013562 this listener. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013563 "ssl-default-bind-options". See also "ssl-min-ver" and "ssl-max-ver".
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013564
13565force-tlsv11
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013566 This option enforces use of TLSv1.1 only on SSL connections instantiated from
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013567 this listener. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013568 "ssl-default-bind-options". See also "ssl-min-ver" and "ssl-max-ver".
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013569
13570force-tlsv12
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013571 This option enforces use of TLSv1.2 only on SSL connections instantiated from
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013572 this listener. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013573 "ssl-default-bind-options". See also "ssl-min-ver" and "ssl-max-ver".
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013574
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020013575force-tlsv13
13576 This option enforces use of TLSv1.3 only on SSL connections instantiated from
13577 this listener. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013578 "ssl-default-bind-options". See also "ssl-min-ver" and "ssl-max-ver".
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020013579
Christopher Faulet31af49d2015-06-09 17:29:50 +020013580generate-certificates
13581 This setting is only available when support for OpenSSL was built in. It
13582 enables the dynamic SSL certificates generation. A CA certificate and its
13583 private key are necessary (see 'ca-sign-file'). When HAProxy is configured as
13584 a transparent forward proxy, SSL requests generate errors because of a common
13585 name mismatch on the certificate presented to the client. With this option
13586 enabled, HAProxy will try to forge a certificate using the SNI hostname
13587 indicated by the client. This is done only if no certificate matches the SNI
13588 hostname (see 'crt-list'). If an error occurs, the default certificate is
13589 used, else the 'strict-sni' option is set.
13590 It can also be used when HAProxy is configured as a reverse proxy to ease the
13591 deployment of an architecture with many backends.
13592
13593 Creating a SSL certificate is an expensive operation, so a LRU cache is used
13594 to store forged certificates (see 'tune.ssl.ssl-ctx-cache-size'). It
Davor Ocelice9ed2812017-12-25 17:49:28 +010013595 increases the HAProxy's memory footprint to reduce latency when the same
Christopher Faulet31af49d2015-06-09 17:29:50 +020013596 certificate is used many times.
13597
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013598gid <gid>
13599 Sets the group of the UNIX sockets to the designated system gid. It can also
13600 be set by default in the global section's "unix-bind" statement. Note that
13601 some platforms simply ignore this. This setting is equivalent to the "group"
13602 setting except that the group ID is used instead of its name. This setting is
13603 ignored by non UNIX sockets.
13604
13605group <group>
13606 Sets the group of the UNIX sockets to the designated system group. It can
13607 also be set by default in the global section's "unix-bind" statement. Note
13608 that some platforms simply ignore this. This setting is equivalent to the
13609 "gid" setting except that the group name is used instead of its gid. This
13610 setting is ignored by non UNIX sockets.
13611
13612id <id>
13613 Fixes the socket ID. By default, socket IDs are automatically assigned, but
13614 sometimes it is more convenient to fix them to ease monitoring. This value
13615 must be strictly positive and unique within the listener/frontend. This
13616 option can only be used when defining only a single socket.
13617
13618interface <interface>
Lukas Tribusfce2e962013-02-12 22:13:19 +010013619 Restricts the socket to a specific interface. When specified, only packets
13620 received from that particular interface are processed by the socket. This is
13621 currently only supported on Linux. The interface must be a primary system
13622 interface, not an aliased interface. It is also possible to bind multiple
13623 frontends to the same address if they are bound to different interfaces. Note
13624 that binding to a network interface requires root privileges. This parameter
Jérôme Magnin61275192018-02-07 11:39:58 +010013625 is only compatible with TCPv4/TCPv6 sockets. When specified, return traffic
13626 uses the same interface as inbound traffic, and its associated routing table,
13627 even if there are explicit routes through different interfaces configured.
13628 This can prove useful to address asymmetric routing issues when the same
13629 client IP addresses need to be able to reach frontends hosted on different
13630 interfaces.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013631
Willy Tarreauabb175f2012-09-24 12:43:26 +020013632level <level>
13633 This setting is used with the stats sockets only to restrict the nature of
13634 the commands that can be issued on the socket. It is ignored by other
13635 sockets. <level> can be one of :
Davor Ocelice9ed2812017-12-25 17:49:28 +010013636 - "user" is the least privileged level; only non-sensitive stats can be
Willy Tarreauabb175f2012-09-24 12:43:26 +020013637 read, and no change is allowed. It would make sense on systems where it
13638 is not easy to restrict access to the socket.
13639 - "operator" is the default level and fits most common uses. All data can
Davor Ocelice9ed2812017-12-25 17:49:28 +010013640 be read, and only non-sensitive changes are permitted (e.g. clear max
Willy Tarreauabb175f2012-09-24 12:43:26 +020013641 counters).
Davor Ocelice9ed2812017-12-25 17:49:28 +010013642 - "admin" should be used with care, as everything is permitted (e.g. clear
Willy Tarreauabb175f2012-09-24 12:43:26 +020013643 all counters).
13644
Andjelko Iharosc4df59e2017-07-20 11:59:48 +020013645severity-output <format>
13646 This setting is used with the stats sockets only to configure severity
13647 level output prepended to informational feedback messages. Severity
13648 level of messages can range between 0 and 7, conforming to syslog
13649 rfc5424. Valid and successful socket commands requesting data
13650 (i.e. "show map", "get acl foo" etc.) will never have a severity level
13651 prepended. It is ignored by other sockets. <format> can be one of :
13652 - "none" (default) no severity level is prepended to feedback messages.
13653 - "number" severity level is prepended as a number.
13654 - "string" severity level is prepended as a string following the
13655 rfc5424 convention.
13656
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013657maxconn <maxconn>
13658 Limits the sockets to this number of concurrent connections. Extraneous
13659 connections will remain in the system's backlog until a connection is
13660 released. If unspecified, the limit will be the same as the frontend's
13661 maxconn. Note that in case of port ranges or multiple addresses, the same
13662 value will be applied to each socket. This setting enables different
13663 limitations on expensive sockets, for instance SSL entries which may easily
13664 eat all memory.
13665
13666mode <mode>
13667 Sets the octal mode used to define access permissions on the UNIX socket. It
13668 can also be set by default in the global section's "unix-bind" statement.
13669 Note that some platforms simply ignore this. This setting is ignored by non
13670 UNIX sockets.
13671
13672mss <maxseg>
13673 Sets the TCP Maximum Segment Size (MSS) value to be advertised on incoming
13674 connections. This can be used to force a lower MSS for certain specific
13675 ports, for instance for connections passing through a VPN. Note that this
13676 relies on a kernel feature which is theoretically supported under Linux but
13677 was buggy in all versions prior to 2.6.28. It may or may not work on other
13678 operating systems. It may also not change the advertised value but change the
13679 effective size of outgoing segments. The commonly advertised value for TCPv4
13680 over Ethernet networks is 1460 = 1500(MTU) - 40(IP+TCP). If this value is
13681 positive, it will be used as the advertised MSS. If it is negative, it will
13682 indicate by how much to reduce the incoming connection's advertised MSS for
13683 outgoing segments. This parameter is only compatible with TCP v4/v6 sockets.
13684
13685name <name>
13686 Sets an optional name for these sockets, which will be reported on the stats
13687 page.
13688
Willy Tarreaud72f0f32015-10-13 14:50:22 +020013689namespace <name>
13690 On Linux, it is possible to specify which network namespace a socket will
13691 belong to. This directive makes it possible to explicitly bind a listener to
13692 a namespace different from the default one. Please refer to your operating
13693 system's documentation to find more details about network namespaces.
13694
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013695nice <nice>
13696 Sets the 'niceness' of connections initiated from the socket. Value must be
13697 in the range -1024..1024 inclusive, and defaults to zero. Positive values
13698 means that such connections are more friendly to others and easily offer
13699 their place in the scheduler. On the opposite, negative values mean that
13700 connections want to run with a higher priority than others. The difference
13701 only happens under high loads when the system is close to saturation.
13702 Negative values are appropriate for low-latency or administration services,
13703 and high values are generally recommended for CPU intensive tasks such as SSL
13704 processing or bulk transfers which are less sensible to latency. For example,
13705 it may make sense to use a positive value for an SMTP socket and a negative
13706 one for an RDP socket.
13707
Emmanuel Hocdet174dfe52017-07-28 15:01:05 +020013708no-ca-names
13709 This setting is only available when support for OpenSSL was built in. It
13710 prevents from send CA names in server hello message when ca-file is used.
Emmanuel Hocdet842e94e2019-12-16 16:39:17 +010013711 Use "ca-verify-file" instead of "ca-file" with "no-ca-names".
Emmanuel Hocdet174dfe52017-07-28 15:01:05 +020013712
Emeric Brun9b3009b2012-10-05 11:55:06 +020013713no-sslv3
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013714 This setting is only available when support for OpenSSL was built in. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013715 disables support for SSLv3 on any sockets instantiated from the listener when
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013716 SSL is supported. Note that SSLv2 is forced disabled in the code and cannot
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013717 be enabled using any configuration option. This option is also available on
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013718 global statement "ssl-default-bind-options". Use "ssl-min-ver" and
13719 "ssl-max-ver" instead.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013720
Emeric Brun90ad8722012-10-02 14:00:59 +020013721no-tls-tickets
13722 This setting is only available when support for OpenSSL was built in. It
13723 disables the stateless session resumption (RFC 5077 TLS Ticket
13724 extension) and force to use stateful session resumption. Stateless
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013725 session resumption is more expensive in CPU usage. This option is also
13726 available on global statement "ssl-default-bind-options".
Lukas Tribusbdb386d2020-03-10 00:56:09 +010013727 The TLS ticket mechanism is only used up to TLS 1.2.
13728 Forward Secrecy is compromised with TLS tickets, unless ticket keys
13729 are periodically rotated (via reload or by using "tls-ticket-keys").
Emeric Brun90ad8722012-10-02 14:00:59 +020013730
Emeric Brun9b3009b2012-10-05 11:55:06 +020013731no-tlsv10
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013732 This setting is only available when support for OpenSSL was built in. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013733 disables support for TLSv1.0 on any sockets instantiated from the listener
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013734 when SSL is supported. Note that SSLv2 is forced disabled in the code and
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013735 cannot be enabled using any configuration option. This option is also
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013736 available on global statement "ssl-default-bind-options". Use "ssl-min-ver"
13737 and "ssl-max-ver" instead.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013738
Emeric Brun9b3009b2012-10-05 11:55:06 +020013739no-tlsv11
Emeric Brunf5da4932012-09-28 19:42:54 +020013740 This setting is only available when support for OpenSSL was built in. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013741 disables support for TLSv1.1 on any sockets instantiated from the listener
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013742 when SSL is supported. Note that SSLv2 is forced disabled in the code and
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013743 cannot be enabled using any configuration option. This option is also
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013744 available on global statement "ssl-default-bind-options". Use "ssl-min-ver"
13745 and "ssl-max-ver" instead.
Emeric Brunf5da4932012-09-28 19:42:54 +020013746
Emeric Brun9b3009b2012-10-05 11:55:06 +020013747no-tlsv12
Emeric Brunf5da4932012-09-28 19:42:54 +020013748 This setting is only available when support for OpenSSL was built in. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013749 disables support for TLSv1.2 on any sockets instantiated from the listener
Emeric Brun2cb7ae52012-10-05 14:14:21 +020013750 when SSL is supported. Note that SSLv2 is forced disabled in the code and
Emeric Brun2c86cbf2014-10-30 15:56:50 +010013751 cannot be enabled using any configuration option. This option is also
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013752 available on global statement "ssl-default-bind-options". Use "ssl-min-ver"
13753 and "ssl-max-ver" instead.
Emeric Brunf5da4932012-09-28 19:42:54 +020013754
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020013755no-tlsv13
13756 This setting is only available when support for OpenSSL was built in. It
13757 disables support for TLSv1.3 on any sockets instantiated from the listener
13758 when SSL is supported. Note that SSLv2 is forced disabled in the code and
13759 cannot be enabled using any configuration option. This option is also
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013760 available on global statement "ssl-default-bind-options". Use "ssl-min-ver"
13761 and "ssl-max-ver" instead.
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020013762
Willy Tarreau6c9a3d52012-10-18 18:57:14 +020013763npn <protocols>
13764 This enables the NPN TLS extension and advertises the specified protocol list
13765 as supported on top of NPN. The protocol list consists in a comma-delimited
13766 list of protocol names, for instance: "http/1.1,http/1.0" (without quotes).
John Roeslerfb2fce12019-07-10 15:45:51 -050013767 This requires that the SSL library is built with support for TLS extensions
Willy Tarreauab861d32013-04-02 02:30:41 +020013768 enabled (check with haproxy -vv). Note that the NPN extension has been
Willy Tarreau95c4e142017-11-26 12:18:55 +010013769 replaced with the ALPN extension (see the "alpn" keyword), though this one is
13770 only available starting with OpenSSL 1.0.2. If HTTP/2 is desired on an older
13771 version of OpenSSL, NPN might still be used as most clients still support it
13772 at the time of writing this. It is possible to enable both NPN and ALPN
13773 though it probably doesn't make any sense out of testing.
Willy Tarreau6c9a3d52012-10-18 18:57:14 +020013774
Lukas Tribus53ae85c2017-05-04 15:45:40 +000013775prefer-client-ciphers
13776 Use the client's preference when selecting the cipher suite, by default
13777 the server's preference is enforced. This option is also available on
13778 global statement "ssl-default-bind-options".
Lukas Tribus926594f2018-05-18 17:55:57 +020013779 Note that with OpenSSL >= 1.1.1 ChaCha20-Poly1305 is reprioritized anyway
13780 (without setting this option), if a ChaCha20-Poly1305 cipher is at the top of
13781 the client cipher list.
Lukas Tribus53ae85c2017-05-04 15:45:40 +000013782
Christopher Fauletc644fa92017-11-23 22:44:11 +010013783process <process-set>[/<thread-set>]
Willy Tarreaua36b3242019-02-02 13:14:34 +010013784 This restricts the list of processes or threads on which this listener is
Christopher Fauletc644fa92017-11-23 22:44:11 +010013785 allowed to run. It does not enforce any process but eliminates those which do
Davor Ocelice9ed2812017-12-25 17:49:28 +010013786 not match. If the frontend uses a "bind-process" setting, the intersection
Christopher Fauletc644fa92017-11-23 22:44:11 +010013787 between the two is applied. If in the end the listener is not allowed to run
13788 on any remaining process, a warning is emitted, and the listener will either
13789 run on the first process of the listener if a single process was specified,
13790 or on all of its processes if multiple processes were specified. If a thread
Davor Ocelice9ed2812017-12-25 17:49:28 +010013791 set is specified, it limits the threads allowed to process incoming
Willy Tarreaua36b3242019-02-02 13:14:34 +010013792 connections for this listener, for the the process set. If multiple processes
13793 and threads are configured, a warning is emitted, as it either results from a
13794 configuration error or a misunderstanding of these models. For the unlikely
13795 case where several ranges are needed, this directive may be repeated.
13796 <process-set> and <thread-set> must use the format
Christopher Fauletc644fa92017-11-23 22:44:11 +010013797
13798 all | odd | even | number[-[number]]
13799
13800 Ranges can be partially defined. The higher bound can be omitted. In such
13801 case, it is replaced by the corresponding maximum value. The main purpose of
13802 this directive is to be used with the stats sockets and have one different
13803 socket per process. The second purpose is to have multiple bind lines sharing
13804 the same IP:port but not the same process in a listener, so that the system
13805 can distribute the incoming connections into multiple queues and allow a
13806 smoother inter-process load balancing. Currently Linux 3.9 and above is known
13807 for supporting this. See also "bind-process" and "nbproc".
Willy Tarreau6ae1ba62014-05-07 19:01:58 +020013808
Christopher Fauleta717b992018-04-10 14:43:00 +020013809proto <name>
13810 Forces the multiplexer's protocol to use for the incoming connections. It
13811 must be compatible with the mode of the frontend (TCP or HTTP). It must also
13812 be usable on the frontend side. The list of available protocols is reported
Christopher Faulet982e17d2021-03-26 14:44:18 +010013813 in haproxy -vv. The protocols properties are reported : the mode (TCP/HTTP),
13814 the side (FE/BE), the mux name and its flags.
13815
13816 Some protocols report errors on aborts (flag=CLEAN_ABRT). Some others are
13817 subject to the head-of-line blocking on server side (flag=HOL_RISK). Finally
13818 some protocols don't support upgrades (flag=NO_UPG). The HTX compatibility is
13819 also reported (flag=HTX).
13820
13821 Here are the protocols that may be used as argument to a "proto" directive on
13822 a bind line :
13823
13824 h2 : mode=HTTP side=FE|BE mux=H2 flags=HTX|CLEAN_ABRT|HOL_RISK|NO_UPG
13825 h1 : mode=HTTP side=FE|BE mux=H1 flags=HTX|NO_UPG
13826 none : mode=TCP side=FE|BE mux=PASS flags=NO_UPG
13827
Daniel Corbett67a82712020-07-06 23:01:19 -040013828 Idea behind this option is to bypass the selection of the best multiplexer's
Christopher Fauleta717b992018-04-10 14:43:00 +020013829 protocol for all connections instantiated from this listening socket. For
Joseph Herlant71b4b152018-11-13 16:55:16 -080013830 instance, it is possible to force the http/2 on clear TCP by specifying "proto
Christopher Fauleta717b992018-04-10 14:43:00 +020013831 h2" on the bind line.
13832
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013833ssl
13834 This setting is only available when support for OpenSSL was built in. It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013835 enables SSL deciphering on connections instantiated from this listener. A
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013836 certificate is necessary (see "crt" above). All contents in the buffers will
13837 appear in clear text, so that ACLs and HTTP processing will only have access
Emmanuel Hocdetbd695fe2017-05-15 15:53:41 +020013838 to deciphered contents. SSLv3 is disabled per default, use "ssl-min-ver SSLv3"
13839 to enable it.
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013840
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013841ssl-max-ver [ SSLv3 | TLSv1.0 | TLSv1.1 | TLSv1.2 | TLSv1.3 ]
13842 This option enforces use of <version> or lower on SSL connections instantiated
William Lallemand50df1cb2020-06-02 10:52:24 +020013843 from this listener. Using this setting without "ssl-min-ver" can be
13844 ambiguous because the default ssl-min-ver value could change in future HAProxy
13845 versions. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013846 "ssl-default-bind-options". See also "ssl-min-ver".
13847
13848ssl-min-ver [ SSLv3 | TLSv1.0 | TLSv1.1 | TLSv1.2 | TLSv1.3 ]
William Lallemand50df1cb2020-06-02 10:52:24 +020013849 This option enforces use of <version> or upper on SSL connections
13850 instantiated from this listener. The default value is "TLSv1.2". This option
13851 is also available on global statement "ssl-default-bind-options".
13852 See also "ssl-max-ver".
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020013853
Emmanuel Hocdet65623372013-01-24 17:17:15 +010013854strict-sni
13855 This setting is only available when support for OpenSSL was built in. The
13856 SSL/TLS negotiation is allow only if the client provided an SNI which match
13857 a certificate. The default certificate is not used.
13858 See the "crt" option for more information.
13859
Willy Tarreau2af207a2015-02-04 00:45:58 +010013860tcp-ut <delay>
Tim Düsterhus4896c442016-11-29 02:15:19 +010013861 Sets the TCP User Timeout for all incoming connections instantiated from this
Willy Tarreau2af207a2015-02-04 00:45:58 +010013862 listening socket. This option is available on Linux since version 2.6.37. It
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013863 allows HAProxy to configure a timeout for sockets which contain data not
Davor Ocelice9ed2812017-12-25 17:49:28 +010013864 receiving an acknowledgment for the configured delay. This is especially
Willy Tarreau2af207a2015-02-04 00:45:58 +010013865 useful on long-lived connections experiencing long idle periods such as
13866 remote terminals or database connection pools, where the client and server
13867 timeouts must remain high to allow a long period of idle, but where it is
13868 important to detect that the client has disappeared in order to release all
13869 resources associated with its connection (and the server's session). The
13870 argument is a delay expressed in milliseconds by default. This only works
13871 for regular TCP connections, and is ignored for other protocols.
13872
Willy Tarreau1c862c52012-10-05 16:21:00 +020013873tfo
Lukas Tribus0defb902013-02-13 23:35:39 +010013874 Is an optional keyword which is supported only on Linux kernels >= 3.7. It
Willy Tarreau1c862c52012-10-05 16:21:00 +020013875 enables TCP Fast Open on the listening socket, which means that clients which
13876 support this feature will be able to send a request and receive a response
13877 during the 3-way handshake starting from second connection, thus saving one
13878 round-trip after the first connection. This only makes sense with protocols
13879 that use high connection rates and where each round trip matters. This can
13880 possibly cause issues with many firewalls which do not accept data on SYN
13881 packets, so this option should only be enabled once well tested. This option
Lukas Tribus0999f762013-04-02 16:43:24 +020013882 is only supported on TCPv4/TCPv6 sockets and ignored by other ones. You may
13883 need to build HAProxy with USE_TFO=1 if your libc doesn't define
13884 TCP_FASTOPEN.
Willy Tarreau1c862c52012-10-05 16:21:00 +020013885
Nenad Merdanovic188ad3e2015-02-27 19:56:50 +010013886tls-ticket-keys <keyfile>
13887 Sets the TLS ticket keys file to load the keys from. The keys need to be 48
Emeric Brun9e754772019-01-10 17:51:55 +010013888 or 80 bytes long, depending if aes128 or aes256 is used, encoded with base64
13889 with one line per key (ex. openssl rand 80 | openssl base64 -A | xargs echo).
13890 The first key determines the key length used for next keys: you can't mix
13891 aes128 and aes256 keys. Number of keys is specified by the TLS_TICKETS_NO
13892 build option (default 3) and at least as many keys need to be present in
13893 the file. Last TLS_TICKETS_NO keys will be used for decryption and the
13894 penultimate one for encryption. This enables easy key rotation by just
13895 appending new key to the file and reloading the process. Keys must be
13896 periodically rotated (ex. every 12h) or Perfect Forward Secrecy is
13897 compromised. It is also a good idea to keep the keys off any permanent
Nenad Merdanovic188ad3e2015-02-27 19:56:50 +010013898 storage such as hard drives (hint: use tmpfs and don't swap those files).
13899 Lifetime hint can be changed using tune.ssl.timeout.
13900
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013901transparent
13902 Is an optional keyword which is supported only on certain Linux kernels. It
13903 indicates that the addresses will be bound even if they do not belong to the
13904 local machine, and that packets targeting any of these addresses will be
13905 intercepted just as if the addresses were locally configured. This normally
13906 requires that IP forwarding is enabled. Caution! do not use this with the
13907 default address '*', as it would redirect any traffic for the specified port.
13908 This keyword is available only when HAProxy is built with USE_LINUX_TPROXY=1.
13909 This parameter is only compatible with TCPv4 and TCPv6 sockets, depending on
13910 kernel version. Some distribution kernels include backports of the feature,
13911 so check for support with your vendor.
13912
Willy Tarreau77e3af92012-11-24 15:07:23 +010013913v4v6
13914 Is an optional keyword which is supported only on most recent systems
13915 including Linux kernels >= 2.4.21. It is used to bind a socket to both IPv4
13916 and IPv6 when it uses the default address. Doing so is sometimes necessary
13917 on systems which bind to IPv6 only by default. It has no effect on non-IPv6
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030013918 sockets, and is overridden by the "v6only" option.
Willy Tarreau77e3af92012-11-24 15:07:23 +010013919
Willy Tarreau9b6700f2012-11-24 11:55:28 +010013920v6only
13921 Is an optional keyword which is supported only on most recent systems
13922 including Linux kernels >= 2.4.21. It is used to bind a socket to IPv6 only
13923 when it uses the default address. Doing so is sometimes preferred to doing it
Willy Tarreau77e3af92012-11-24 15:07:23 +010013924 system-wide as it is per-listener. It has no effect on non-IPv6 sockets and
13925 has precedence over the "v4v6" option.
Willy Tarreau9b6700f2012-11-24 11:55:28 +010013926
Willy Tarreaub6205fd2012-09-24 12:27:33 +020013927uid <uid>
13928 Sets the owner of the UNIX sockets to the designated system uid. It can also
13929 be set by default in the global section's "unix-bind" statement. Note that
13930 some platforms simply ignore this. This setting is equivalent to the "user"
13931 setting except that the user numeric ID is used instead of its name. This
13932 setting is ignored by non UNIX sockets.
13933
13934user <user>
13935 Sets the owner of the UNIX sockets to the designated system user. It can also
13936 be set by default in the global section's "unix-bind" statement. Note that
13937 some platforms simply ignore this. This setting is equivalent to the "uid"
13938 setting except that the user name is used instead of its uid. This setting is
13939 ignored by non UNIX sockets.
13940
Emeric Brun1a073b42012-09-28 17:07:34 +020013941verify [none|optional|required]
13942 This setting is only available when support for OpenSSL was built in. If set
13943 to 'none', client certificate is not requested. This is the default. In other
13944 cases, a client certificate is requested. If the client does not provide a
13945 certificate after the request and if 'verify' is set to 'required', then the
13946 handshake is aborted, while it would have succeeded if set to 'optional'. The
Emeric Brunfd33a262012-10-11 16:28:27 +020013947 certificate provided by the client is always verified using CAs from
13948 'ca-file' and optional CRLs from 'crl-file'. On verify failure the handshake
13949 is aborted, regardless of the 'verify' option, unless the error code exactly
13950 matches one of those listed with 'ca-ignore-err' or 'crt-ignore-err'.
Willy Tarreau4a5cade2012-04-05 21:09:48 +020013951
Willy Tarreaub6205fd2012-09-24 12:27:33 +0200139525.2. Server and default-server options
Cyril Bontéf0c60612010-02-06 14:44:47 +010013953------------------------------------
Willy Tarreau6a06a402007-07-15 20:15:28 +020013954
Krzysztof Piotr Oledzkic6df0662010-01-05 16:38:49 +010013955The "server" and "default-server" keywords support a certain number of settings
13956which are all passed as arguments on the server line. The order in which those
13957arguments appear does not count, and they are all optional. Some of those
13958settings are single words (booleans) while others expect one or several values
13959after them. In this case, the values must immediately follow the setting name.
13960Except default-server, all those settings must be specified after the server's
13961address if they are used:
Willy Tarreau6a06a402007-07-15 20:15:28 +020013962
Willy Tarreauc57f0e22009-05-10 13:12:33 +020013963 server <name> <address>[:port] [settings ...]
Krzysztof Piotr Oledzkic6df0662010-01-05 16:38:49 +010013964 default-server [settings ...]
Willy Tarreau6a06a402007-07-15 20:15:28 +020013965
Frédéric Lécailled2376272017-03-21 18:52:12 +010013966Note that all these settings are supported both by "server" and "default-server"
13967keywords, except "id" which is only supported by "server".
13968
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010013969The currently supported settings are the following ones.
Willy Tarreau0ba27502007-12-24 16:55:16 +010013970
Willy Tarreauceb4ac92012-04-28 00:41:46 +020013971addr <ipv4|ipv6>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020013972 Using the "addr" parameter, it becomes possible to use a different IP address
Baptiste Assmann13f83532016-03-06 23:14:36 +010013973 to send health-checks or to probe the agent-check. On some servers, it may be
13974 desirable to dedicate an IP address to specific component able to perform
13975 complex tests which are more suitable to health-checks than the application.
13976 This parameter is ignored if the "check" parameter is not set. See also the
13977 "port" parameter.
Willy Tarreau6a06a402007-07-15 20:15:28 +020013978
Simon Hormand60d6912013-11-25 10:46:36 +090013979agent-check
13980 Enable an auxiliary agent check which is run independently of a regular
Willy Tarreau81f5d942013-12-09 20:51:51 +010013981 health check. An agent health check is performed by making a TCP connection
Willy Tarreau7a0139e2018-12-16 08:42:56 +010013982 to the port set by the "agent-port" parameter and reading an ASCII string
13983 terminated by the first '\r' or '\n' met. The string is made of a series of
13984 words delimited by spaces, tabs or commas in any order, each consisting of :
Simon Hormand60d6912013-11-25 10:46:36 +090013985
Willy Tarreau81f5d942013-12-09 20:51:51 +010013986 - An ASCII representation of a positive integer percentage, e.g. "75%".
Simon Hormand60d6912013-11-25 10:46:36 +090013987 Values in this format will set the weight proportional to the initial
Daniel Corbett9f0843f2021-05-08 10:50:37 -040013988 weight of a server as configured when HAProxy starts. Note that a zero
Willy Tarreauc5af3a62014-10-07 15:27:33 +020013989 weight is reported on the stats page as "DRAIN" since it has the same
13990 effect on the server (it's removed from the LB farm).
Simon Hormand60d6912013-11-25 10:46:36 +090013991
Davor Ocelice9ed2812017-12-25 17:49:28 +010013992 - The string "maxconn:" followed by an integer (no space between). Values
13993 in this format will set the maxconn of a server. The maximum number of
13994 connections advertised needs to be multiplied by the number of load
13995 balancers and different backends that use this health check to get the
13996 total number of connections the server might receive. Example: maxconn:30
Nenad Merdanovic174dd372016-04-24 23:10:06 +020013997
Willy Tarreau81f5d942013-12-09 20:51:51 +010013998 - The word "ready". This will turn the server's administrative state to the
Davor Ocelice9ed2812017-12-25 17:49:28 +010013999 READY mode, thus canceling any DRAIN or MAINT state
Simon Hormand60d6912013-11-25 10:46:36 +090014000
Willy Tarreau81f5d942013-12-09 20:51:51 +010014001 - The word "drain". This will turn the server's administrative state to the
14002 DRAIN mode, thus it will not accept any new connections other than those
14003 that are accepted via persistence.
Simon Hormand60d6912013-11-25 10:46:36 +090014004
Willy Tarreau81f5d942013-12-09 20:51:51 +010014005 - The word "maint". This will turn the server's administrative state to the
14006 MAINT mode, thus it will not accept any new connections at all, and health
14007 checks will be stopped.
Simon Hormand60d6912013-11-25 10:46:36 +090014008
William Dauchyf8e795c2020-09-26 13:35:51 +020014009 - The words "down", "fail", or "stopped", optionally followed by a
Willy Tarreau81f5d942013-12-09 20:51:51 +010014010 description string after a sharp ('#'). All of these mark the server's
14011 operating state as DOWN, but since the word itself is reported on the stats
14012 page, the difference allows an administrator to know if the situation was
14013 expected or not : the service may intentionally be stopped, may appear up
Davor Ocelice9ed2812017-12-25 17:49:28 +010014014 but fail some validity tests, or may be seen as down (e.g. missing process,
Willy Tarreau81f5d942013-12-09 20:51:51 +010014015 or port not responding).
Simon Hormand60d6912013-11-25 10:46:36 +090014016
Willy Tarreau81f5d942013-12-09 20:51:51 +010014017 - The word "up" sets back the server's operating state as UP if health checks
14018 also report that the service is accessible.
Simon Hormand60d6912013-11-25 10:46:36 +090014019
Willy Tarreau81f5d942013-12-09 20:51:51 +010014020 Parameters which are not advertised by the agent are not changed. For
14021 example, an agent might be designed to monitor CPU usage and only report a
14022 relative weight and never interact with the operating status. Similarly, an
14023 agent could be designed as an end-user interface with 3 radio buttons
14024 allowing an administrator to change only the administrative state. However,
14025 it is important to consider that only the agent may revert its own actions,
14026 so if a server is set to DRAIN mode or to DOWN state using the agent, the
14027 agent must implement the other equivalent actions to bring the service into
14028 operations again.
Simon Hormand60d6912013-11-25 10:46:36 +090014029
Simon Horman2f1f9552013-11-25 10:46:37 +090014030 Failure to connect to the agent is not considered an error as connectivity
14031 is tested by the regular health check which is enabled by the "check"
Willy Tarreau81f5d942013-12-09 20:51:51 +010014032 parameter. Warning though, it is not a good idea to stop an agent after it
14033 reports "down", since only an agent reporting "up" will be able to turn the
14034 server up again. Note that the CLI on the Unix stats socket is also able to
Willy Tarreau989222a2016-01-15 10:26:26 +010014035 force an agent's result in order to work around a bogus agent if needed.
Simon Horman2f1f9552013-11-25 10:46:37 +090014036
Willy Tarreau81f5d942013-12-09 20:51:51 +010014037 Requires the "agent-port" parameter to be set. See also the "agent-inter"
Frédéric Lécailled2376272017-03-21 18:52:12 +010014038 and "no-agent-check" parameters.
Simon Hormand60d6912013-11-25 10:46:36 +090014039
James Brown55f9ff12015-10-21 18:19:05 -070014040agent-send <string>
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014041 If this option is specified, HAProxy will send the given string (verbatim)
James Brown55f9ff12015-10-21 18:19:05 -070014042 to the agent server upon connection. You could, for example, encode
14043 the backend name into this string, which would enable your agent to send
14044 different responses based on the backend. Make sure to include a '\n' if
14045 you want to terminate your request with a newline.
14046
Simon Hormand60d6912013-11-25 10:46:36 +090014047agent-inter <delay>
14048 The "agent-inter" parameter sets the interval between two agent checks
14049 to <delay> milliseconds. If left unspecified, the delay defaults to 2000 ms.
14050
14051 Just as with every other time-based parameter, it may be entered in any
14052 other explicit unit among { us, ms, s, m, h, d }. The "agent-inter"
14053 parameter also serves as a timeout for agent checks "timeout check" is
14054 not set. In order to reduce "resonance" effects when multiple servers are
14055 hosted on the same hardware, the agent and health checks of all servers
14056 are started with a small time offset between them. It is also possible to
14057 add some random noise in the agent and health checks interval using the
14058 global "spread-checks" keyword. This makes sense for instance when a lot
14059 of backends use the same servers.
14060
14061 See also the "agent-check" and "agent-port" parameters.
14062
Misiek768d8602017-01-09 09:52:43 +010014063agent-addr <addr>
14064 The "agent-addr" parameter sets address for agent check.
14065
14066 You can offload agent-check to another target, so you can make single place
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014067 managing status and weights of servers defined in HAProxy in case you can't
Misiek768d8602017-01-09 09:52:43 +010014068 make self-aware and self-managing services. You can specify both IP or
14069 hostname, it will be resolved.
14070
Simon Hormand60d6912013-11-25 10:46:36 +090014071agent-port <port>
14072 The "agent-port" parameter sets the TCP port used for agent checks.
14073
14074 See also the "agent-check" and "agent-inter" parameters.
14075
Olivier Houchard8cb2d2e2019-05-06 18:58:48 +020014076allow-0rtt
14077 Allow sending early data to the server when using TLS 1.3.
Olivier Houchard22c9b442019-05-06 19:01:04 +020014078 Note that early data will be sent only if the client used early data, or
14079 if the backend uses "retry-on" with the "0rtt-rejected" keyword.
Olivier Houchard8cb2d2e2019-05-06 18:58:48 +020014080
Olivier Houchardc7566002018-11-20 23:33:50 +010014081alpn <protocols>
14082 This enables the TLS ALPN extension and advertises the specified protocol
14083 list as supported on top of ALPN. The protocol list consists in a comma-
14084 delimited list of protocol names, for instance: "http/1.1,http/1.0" (without
John Roeslerfb2fce12019-07-10 15:45:51 -050014085 quotes). This requires that the SSL library is built with support for TLS
Olivier Houchardc7566002018-11-20 23:33:50 +010014086 extensions enabled (check with haproxy -vv). The ALPN extension replaces the
14087 initial NPN extension. ALPN is required to connect to HTTP/2 servers.
14088 Versions of OpenSSL prior to 1.0.2 didn't support ALPN and only supposed the
14089 now obsolete NPN extension.
14090 If both HTTP/2 and HTTP/1.1 are expected to be supported, both versions can
14091 be advertised, in order of preference, like below :
14092
14093 server 127.0.0.1:443 ssl crt pub.pem alpn h2,http/1.1
14094
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014095backup
14096 When "backup" is present on a server line, the server is only used in load
14097 balancing when all other non-backup servers are unavailable. Requests coming
14098 with a persistence cookie referencing the server will always be served
14099 though. By default, only the first operational backup server is used, unless
Frédéric Lécailled2376272017-03-21 18:52:12 +010014100 the "allbackups" option is set in the backend. See also the "no-backup" and
14101 "allbackups" options.
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014102
Emeric Brunef42d922012-10-11 16:11:36 +020014103ca-file <cafile>
14104 This setting is only available when support for OpenSSL was built in. It
14105 designates a PEM file from which to load CA certificates used to verify
14106 server's certificate.
14107
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014108check
Jerome Magnin90702bc2020-04-26 14:23:04 +020014109 This option enables health checks on a server:
14110 - when not set, no health checking is performed, and the server is always
14111 considered available.
14112 - when set and no other check method is configured, the server is considered
14113 available when a connection can be established at the highest configured
14114 transport layer. This means TCP by default, or SSL/TLS when "ssl" or
14115 "check-ssl" are set, both possibly combined with connection prefixes such
14116 as a PROXY protocol header when "send-proxy" or "check-send-proxy" are
14117 set.
14118 - when set and an application-level health check is defined, the
14119 application-level exchanges are performed on top of the configured
14120 transport layer and the server is considered available if all of the
14121 exchanges succeed.
14122
14123 By default, health checks are performed on the same address and port as
14124 configured on the server, using the same encapsulation parameters (SSL/TLS,
14125 proxy-protocol header, etc... ). It is possible to change the destination
14126 address using "addr" and the port using "port". When done, it is assumed the
14127 server isn't checked on the service port, and configured encapsulation
Ilya Shipitsin4329a9a2020-05-05 21:17:10 +050014128 parameters are not reused. One must explicitly set "check-send-proxy" to send
Jerome Magnin90702bc2020-04-26 14:23:04 +020014129 connection headers, "check-ssl" to use SSL/TLS.
14130
14131 When "sni" or "alpn" are set on the server line, their value is not used for
14132 health checks and one must use "check-sni" or "check-alpn".
14133
14134 The default source address for health check traffic is the same as the one
14135 defined in the backend. It can be changed with the "source" keyword.
14136
14137 The interval between checks can be set using the "inter" keyword, and the
14138 "rise" and "fall" keywords can be used to define how many successful or
14139 failed health checks are required to flag a server available or not
14140 available.
14141
14142 Optional application-level health checks can be configured with "option
14143 httpchk", "option mysql-check" "option smtpchk", "option pgsql-check",
14144 "option ldap-check", or "option redis-check".
14145
14146 Example:
14147 # simple tcp check
14148 backend foo
14149 server s1 192.168.0.1:80 check
14150 # this does a tcp connect + tls handshake
14151 backend foo
14152 server s1 192.168.0.1:443 ssl check
14153 # simple tcp check is enough for check success
14154 backend foo
14155 option tcp-check
14156 tcp-check connect
14157 server s1 192.168.0.1:443 ssl check
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014158
Willy Tarreau6c16adc2012-10-05 00:04:16 +020014159check-send-proxy
14160 This option forces emission of a PROXY protocol line with outgoing health
14161 checks, regardless of whether the server uses send-proxy or not for the
14162 normal traffic. By default, the PROXY protocol is enabled for health checks
14163 if it is already enabled for normal traffic and if no "port" nor "addr"
14164 directive is present. However, if such a directive is present, the
14165 "check-send-proxy" option needs to be used to force the use of the
14166 protocol. See also the "send-proxy" option for more information.
14167
Olivier Houchard92150142018-12-21 19:47:01 +010014168check-alpn <protocols>
14169 Defines which protocols to advertise with ALPN. The protocol list consists in
14170 a comma-delimited list of protocol names, for instance: "http/1.1,http/1.0"
14171 (without quotes). If it is not set, the server ALPN is used.
14172
Christopher Fauletedc6ed92020-04-23 16:27:59 +020014173check-proto <name>
14174 Forces the multiplexer's protocol to use for the server's health-check
14175 connections. It must be compatible with the health-check type (TCP or
14176 HTTP). It must also be usable on the backend side. The list of available
Christopher Faulet982e17d2021-03-26 14:44:18 +010014177 protocols is reported in haproxy -vv. The protocols properties are
14178 reported : the mode (TCP/HTTP), the side (FE/BE), the mux name and its flags.
14179
14180 Some protocols report errors on aborts (flag=CLEAN_ABRT). Some others are
14181 subject to the head-of-line blocking on server side (flag=HOL_RISK). Finally
14182 some protocols don't support upgrades (flag=NO_UPG). The HTX compatibility is
14183 also reported (flag=HTX).
14184
14185 Here are the protocols that may be used as argument to a "check-proto"
14186 directive on a server line:
14187
14188 h2 : mode=HTTP side=FE|BE mux=H2 flags=HTX|CLEAN_ABRT|HOL_RISK|NO_UPG
14189 fcgi : mode=HTTP side=BE mux=FCGI flags=HTX|HOL_RISK|NO_UPG
14190 h1 : mode=HTTP side=FE|BE mux=H1 flags=HTX|NO_UPG
14191 none : mode=TCP side=FE|BE mux=PASS flags=NO_UPG
14192
Daniel Corbett67a82712020-07-06 23:01:19 -040014193 Idea behind this option is to bypass the selection of the best multiplexer's
Christopher Fauletedc6ed92020-04-23 16:27:59 +020014194 protocol for health-check connections established to this server.
14195 If not defined, the server one will be used, if set.
14196
Jérôme Magninae9bb762018-12-09 16:08:26 +010014197check-sni <sni>
Olivier Houchard9130a962017-10-17 17:33:43 +020014198 This option allows you to specify the SNI to be used when doing health checks
Jérôme Magninae9bb762018-12-09 16:08:26 +010014199 over SSL. It is only possible to use a string to set <sni>. If you want to
14200 set a SNI for proxied traffic, see "sni".
Olivier Houchard9130a962017-10-17 17:33:43 +020014201
Willy Tarreau763a95b2012-10-04 23:15:39 +020014202check-ssl
14203 This option forces encryption of all health checks over SSL, regardless of
14204 whether the server uses SSL or not for the normal traffic. This is generally
14205 used when an explicit "port" or "addr" directive is specified and SSL health
14206 checks are not inherited. It is important to understand that this option
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030014207 inserts an SSL transport layer below the checks, so that a simple TCP connect
Willy Tarreau763a95b2012-10-04 23:15:39 +020014208 check becomes an SSL connect, which replaces the old ssl-hello-chk. The most
14209 common use is to send HTTPS checks by combining "httpchk" with SSL checks.
Davor Ocelice9ed2812017-12-25 17:49:28 +010014210 All SSL settings are common to health checks and traffic (e.g. ciphers).
Frédéric Lécailled2376272017-03-21 18:52:12 +010014211 See the "ssl" option for more information and "no-check-ssl" to disable
14212 this option.
Willy Tarreau763a95b2012-10-04 23:15:39 +020014213
Alexander Liu2a54bb72019-05-22 19:44:48 +080014214check-via-socks4
John Roeslerfb2fce12019-07-10 15:45:51 -050014215 This option enables outgoing health checks using upstream socks4 proxy. By
Alexander Liu2a54bb72019-05-22 19:44:48 +080014216 default, the health checks won't go through socks tunnel even it was enabled
14217 for normal traffic.
14218
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014219ciphers <ciphers>
Dirkjan Bussink415150f2018-09-14 11:14:21 +020014220 This setting is only available when support for OpenSSL was built in. This
14221 option sets the string describing the list of cipher algorithms that is
14222 negotiated during the SSL/TLS handshake with the server. The format of the
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +000014223 string is defined in "man 1 ciphers" from OpenSSL man pages. For background
14224 information and recommendations see e.g.
14225 (https://wiki.mozilla.org/Security/Server_Side_TLS) and
14226 (https://mozilla.github.io/server-side-tls/ssl-config-generator/). For TLSv1.3
14227 cipher configuration, please check the "ciphersuites" keyword.
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014228
Dirkjan Bussink415150f2018-09-14 11:14:21 +020014229ciphersuites <ciphersuites>
14230 This setting is only available when support for OpenSSL was built in and
14231 OpenSSL 1.1.1 or later was used to build HAProxy. This option sets the string
14232 describing the list of cipher algorithms that is negotiated during the TLS
14233 1.3 handshake with the server. The format of the string is defined in
Bertrand Jacquin4f03ab02019-02-03 18:48:49 +000014234 "man 1 ciphers" from OpenSSL man pages under the "ciphersuites" section.
14235 For cipher configuration for TLSv1.2 and earlier, please check the "ciphers"
14236 keyword.
Dirkjan Bussink415150f2018-09-14 11:14:21 +020014237
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014238cookie <value>
14239 The "cookie" parameter sets the cookie value assigned to the server to
14240 <value>. This value will be checked in incoming requests, and the first
14241 operational server possessing the same value will be selected. In return, in
14242 cookie insertion or rewrite modes, this value will be assigned to the cookie
14243 sent to the client. There is nothing wrong in having several servers sharing
14244 the same cookie value, and it is in fact somewhat common between normal and
14245 backup servers. See also the "cookie" keyword in backend section.
14246
Emeric Brunef42d922012-10-11 16:11:36 +020014247crl-file <crlfile>
14248 This setting is only available when support for OpenSSL was built in. It
14249 designates a PEM file from which to load certificate revocation list used
14250 to verify server's certificate.
14251
Emeric Bruna7aa3092012-10-26 12:58:00 +020014252crt <cert>
14253 This setting is only available when support for OpenSSL was built in.
14254 It designates a PEM file from which to load both a certificate and the
14255 associated private key. This file can be built by concatenating both PEM
14256 files into one. This certificate will be sent if the server send a client
14257 certificate request.
14258
Remi Tricot-Le Breton7c980df2021-05-07 15:28:08 +020014259 If the file does not contain a private key, HAProxy will try to load the key
14260 at the same path suffixed by a ".key" (provided the "ssl-load-extra-files"
14261 option is set accordingly).
14262
Willy Tarreau96839092010-03-29 10:02:24 +020014263disabled
14264 The "disabled" keyword starts the server in the "disabled" state. That means
14265 that it is marked down in maintenance mode, and no connection other than the
14266 ones allowed by persist mode will reach it. It is very well suited to setup
14267 new servers, because normal traffic will never reach them, while it is still
14268 possible to test the service by making use of the force-persist mechanism.
Frédéric Lécailled2376272017-03-21 18:52:12 +010014269 See also "enabled" setting.
Willy Tarreau96839092010-03-29 10:02:24 +020014270
Frédéric Lécailled2376272017-03-21 18:52:12 +010014271enabled
14272 This option may be used as 'server' setting to reset any 'disabled'
14273 setting which would have been inherited from 'default-server' directive as
14274 default value.
14275 It may also be used as 'default-server' setting to reset any previous
14276 'default-server' 'disabled' setting.
Willy Tarreau96839092010-03-29 10:02:24 +020014277
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014278error-limit <count>
Willy Tarreau983e01e2010-01-11 18:42:06 +010014279 If health observing is enabled, the "error-limit" parameter specifies the
14280 number of consecutive errors that triggers event selected by the "on-error"
14281 option. By default it is set to 10 consecutive errors.
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014282
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014283 See also the "check", "error-limit" and "on-error".
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014284
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014285fall <count>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014286 The "fall" parameter states that a server will be considered as dead after
14287 <count> consecutive unsuccessful health checks. This value defaults to 3 if
14288 unspecified. See also the "check", "inter" and "rise" parameters.
14289
Emeric Brun8694b9a2012-10-05 14:39:07 +020014290force-sslv3
14291 This option enforces use of SSLv3 only when SSL is used to communicate with
14292 the server. SSLv3 is generally less expensive than the TLS counterparts for
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014293 high connection rates. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014294 "ssl-default-server-options". See also "ssl-min-ver" and ssl-max-ver".
Emeric Brun8694b9a2012-10-05 14:39:07 +020014295
14296force-tlsv10
14297 This option enforces use of TLSv1.0 only when SSL is used to communicate with
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014298 the server. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014299 "ssl-default-server-options". See also "ssl-min-ver" and ssl-max-ver".
Emeric Brun8694b9a2012-10-05 14:39:07 +020014300
14301force-tlsv11
14302 This option enforces use of TLSv1.1 only when SSL is used to communicate with
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014303 the server. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014304 "ssl-default-server-options". See also "ssl-min-ver" and ssl-max-ver".
Emeric Brun8694b9a2012-10-05 14:39:07 +020014305
14306force-tlsv12
14307 This option enforces use of TLSv1.2 only when SSL is used to communicate with
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014308 the server. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014309 "ssl-default-server-options". See also "ssl-min-ver" and ssl-max-ver".
Emeric Brun8694b9a2012-10-05 14:39:07 +020014310
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020014311force-tlsv13
14312 This option enforces use of TLSv1.3 only when SSL is used to communicate with
14313 the server. This option is also available on global statement
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014314 "ssl-default-server-options". See also "ssl-min-ver" and ssl-max-ver".
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020014315
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014316id <value>
Willy Tarreau53fb4ae2009-10-04 23:04:08 +020014317 Set a persistent ID for the server. This ID must be positive and unique for
14318 the proxy. An unused ID will automatically be assigned if unset. The first
14319 assigned value will be 1. This ID is currently only returned in statistics.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014320
Willy Tarreau6a031d12016-11-07 19:42:35 +010014321init-addr {last | libc | none | <ip>},[...]*
14322 Indicate in what order the server's address should be resolved upon startup
14323 if it uses an FQDN. Attempts are made to resolve the address by applying in
Davor Ocelice9ed2812017-12-25 17:49:28 +010014324 turn each of the methods mentioned in the comma-delimited list. The first
Willy Tarreau6a031d12016-11-07 19:42:35 +010014325 method which succeeds is used. If the end of the list is reached without
14326 finding a working method, an error is thrown. Method "last" suggests to pick
14327 the address which appears in the state file (see "server-state-file"). Method
14328 "libc" uses the libc's internal resolver (gethostbyname() or getaddrinfo()
14329 depending on the operating system and build options). Method "none"
14330 specifically indicates that the server should start without any valid IP
14331 address in a down state. It can be useful to ignore some DNS issues upon
14332 startup, waiting for the situation to get fixed later. Finally, an IP address
14333 (IPv4 or IPv6) may be provided. It can be the currently known address of the
Davor Ocelice9ed2812017-12-25 17:49:28 +010014334 server (e.g. filled by a configuration generator), or the address of a dummy
Willy Tarreau6a031d12016-11-07 19:42:35 +010014335 server used to catch old sessions and present them with a decent error
14336 message for example. When the "first" load balancing algorithm is used, this
14337 IP address could point to a fake server used to trigger the creation of new
14338 instances on the fly. This option defaults to "last,libc" indicating that the
14339 previous address found in the state file (if any) is used first, otherwise
14340 the libc's resolver is used. This ensures continued compatibility with the
Davor Ocelice9ed2812017-12-25 17:49:28 +010014341 historic behavior.
Willy Tarreau6a031d12016-11-07 19:42:35 +010014342
14343 Example:
14344 defaults
14345 # never fail on address resolution
14346 default-server init-addr last,libc,none
14347
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014348inter <delay>
14349fastinter <delay>
14350downinter <delay>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014351 The "inter" parameter sets the interval between two consecutive health checks
14352 to <delay> milliseconds. If left unspecified, the delay defaults to 2000 ms.
14353 It is also possible to use "fastinter" and "downinter" to optimize delays
14354 between checks depending on the server state :
14355
Pieter Baauw44fc9df2015-09-17 21:30:46 +020014356 Server state | Interval used
14357 ----------------------------------------+----------------------------------
14358 UP 100% (non-transitional) | "inter"
14359 ----------------------------------------+----------------------------------
14360 Transitionally UP (going down "fall"), | "fastinter" if set,
14361 Transitionally DOWN (going up "rise"), | "inter" otherwise.
14362 or yet unchecked. |
14363 ----------------------------------------+----------------------------------
14364 DOWN 100% (non-transitional) | "downinter" if set,
14365 | "inter" otherwise.
14366 ----------------------------------------+----------------------------------
Willy Tarreaud72758d2010-01-12 10:42:19 +010014367
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014368 Just as with every other time-based parameter, they can be entered in any
14369 other explicit unit among { us, ms, s, m, h, d }. The "inter" parameter also
14370 serves as a timeout for health checks sent to servers if "timeout check" is
14371 not set. In order to reduce "resonance" effects when multiple servers are
Simon Hormand60d6912013-11-25 10:46:36 +090014372 hosted on the same hardware, the agent and health checks of all servers
14373 are started with a small time offset between them. It is also possible to
14374 add some random noise in the agent and health checks interval using the
14375 global "spread-checks" keyword. This makes sense for instance when a lot
14376 of backends use the same servers.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014377
Emeric Brun97556472020-05-30 01:42:45 +020014378log-proto <logproto>
14379 The "log-proto" specifies the protocol used to forward event messages to
14380 a server configured in a ring section. Possible values are "legacy"
14381 and "octet-count" corresponding respectively to "Non-transparent-framing"
14382 and "Octet counting" in rfc6587. "legacy" is the default.
14383
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014384maxconn <maxconn>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014385 The "maxconn" parameter specifies the maximal number of concurrent
14386 connections that will be sent to this server. If the number of incoming
Tim Duesterhuscefbbd92019-11-27 22:35:27 +010014387 concurrent connections goes higher than this value, they will be queued,
14388 waiting for a slot to be released. This parameter is very important as it can
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014389 save fragile servers from going down under extreme loads. If a "minconn"
14390 parameter is specified, the limit becomes dynamic. The default value is "0"
14391 which means unlimited. See also the "minconn" and "maxqueue" parameters, and
14392 the backend's "fullconn" keyword.
14393
Tim Duesterhuscefbbd92019-11-27 22:35:27 +010014394 In HTTP mode this parameter limits the number of concurrent requests instead
14395 of the number of connections. Multiple requests might be multiplexed over a
14396 single TCP connection to the server. As an example if you specify a maxconn
14397 of 50 you might see between 1 and 50 actual server connections, but no more
14398 than 50 concurrent requests.
14399
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014400maxqueue <maxqueue>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014401 The "maxqueue" parameter specifies the maximal number of connections which
14402 will wait in the queue for this server. If this limit is reached, next
14403 requests will be redispatched to other servers instead of indefinitely
14404 waiting to be served. This will break persistence but may allow people to
Willy Tarreau8ae8c482020-10-22 17:19:07 +020014405 quickly re-log in when the server they try to connect to is dying. Some load
14406 balancing algorithms such as leastconn take this into account and accept to
14407 add requests into a server's queue up to this value if it is explicitly set
14408 to a value greater than zero, which often allows to better smooth the load
14409 when dealing with single-digit maxconn values. The default value is "0" which
14410 means the queue is unlimited. See also the "maxconn" and "minconn" parameters
14411 and "balance leastconn".
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014412
Willy Tarreau9c538e02019-01-23 10:21:49 +010014413max-reuse <count>
14414 The "max-reuse" argument indicates the HTTP connection processors that they
14415 should not reuse a server connection more than this number of times to send
14416 new requests. Permitted values are -1 (the default), which disables this
14417 limit, or any positive value. Value zero will effectively disable keep-alive.
14418 This is only used to work around certain server bugs which cause them to leak
14419 resources over time. The argument is not necessarily respected by the lower
14420 layers as there might be technical limitations making it impossible to
14421 enforce. At least HTTP/2 connections to servers will respect it.
14422
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014423minconn <minconn>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014424 When the "minconn" parameter is set, the maxconn limit becomes a dynamic
14425 limit following the backend's load. The server will always accept at least
14426 <minconn> connections, never more than <maxconn>, and the limit will be on
14427 the ramp between both values when the backend has less than <fullconn>
14428 concurrent connections. This makes it possible to limit the load on the
14429 server during normal loads, but push it further for important loads without
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010014430 overloading the server during exceptional loads. See also the "maxconn"
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014431 and "maxqueue" parameters, as well as the "fullconn" backend keyword.
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014432
Willy Tarreaud72f0f32015-10-13 14:50:22 +020014433namespace <name>
14434 On Linux, it is possible to specify which network namespace a socket will
14435 belong to. This directive makes it possible to explicitly bind a server to
14436 a namespace different from the default one. Please refer to your operating
14437 system's documentation to find more details about network namespaces.
14438
Frédéric Lécailled2376272017-03-21 18:52:12 +010014439no-agent-check
14440 This option may be used as "server" setting to reset any "agent-check"
14441 setting which would have been inherited from "default-server" directive as
14442 default value.
14443 It may also be used as "default-server" setting to reset any previous
14444 "default-server" "agent-check" setting.
14445
14446no-backup
14447 This option may be used as "server" setting to reset any "backup"
14448 setting which would have been inherited from "default-server" directive as
14449 default value.
14450 It may also be used as "default-server" setting to reset any previous
14451 "default-server" "backup" setting.
14452
14453no-check
14454 This option may be used as "server" setting to reset any "check"
14455 setting which would have been inherited from "default-server" directive as
14456 default value.
14457 It may also be used as "default-server" setting to reset any previous
14458 "default-server" "check" setting.
14459
14460no-check-ssl
14461 This option may be used as "server" setting to reset any "check-ssl"
14462 setting which would have been inherited from "default-server" directive as
14463 default value.
14464 It may also be used as "default-server" setting to reset any previous
14465 "default-server" "check-ssl" setting.
14466
Frédéric Lécailled2376272017-03-21 18:52:12 +010014467no-send-proxy
14468 This option may be used as "server" setting to reset any "send-proxy"
14469 setting which would have been inherited from "default-server" directive as
14470 default value.
14471 It may also be used as "default-server" setting to reset any previous
14472 "default-server" "send-proxy" setting.
14473
14474no-send-proxy-v2
14475 This option may be used as "server" setting to reset any "send-proxy-v2"
14476 setting which would have been inherited from "default-server" directive as
14477 default value.
14478 It may also be used as "default-server" setting to reset any previous
14479 "default-server" "send-proxy-v2" setting.
14480
14481no-send-proxy-v2-ssl
14482 This option may be used as "server" setting to reset any "send-proxy-v2-ssl"
14483 setting which would have been inherited from "default-server" directive as
14484 default value.
14485 It may also be used as "default-server" setting to reset any previous
14486 "default-server" "send-proxy-v2-ssl" setting.
14487
14488no-send-proxy-v2-ssl-cn
14489 This option may be used as "server" setting to reset any "send-proxy-v2-ssl-cn"
14490 setting which would have been inherited from "default-server" directive as
14491 default value.
14492 It may also be used as "default-server" setting to reset any previous
14493 "default-server" "send-proxy-v2-ssl-cn" setting.
14494
14495no-ssl
14496 This option may be used as "server" setting to reset any "ssl"
14497 setting which would have been inherited from "default-server" directive as
14498 default value.
14499 It may also be used as "default-server" setting to reset any previous
14500 "default-server" "ssl" setting.
14501
William Dauchyf6370442020-11-14 19:25:33 +010014502 Note that using `default-server ssl` setting and `no-ssl` on server will
14503 however init SSL connection, so it can be later be enabled through the
14504 runtime API: see `set server` commands in management doc.
14505
Willy Tarreau2a3fb1c2015-02-05 16:47:07 +010014506no-ssl-reuse
14507 This option disables SSL session reuse when SSL is used to communicate with
14508 the server. It will force the server to perform a full handshake for every
14509 new connection. It's probably only useful for benchmarking, troubleshooting,
14510 and for paranoid users.
14511
Emeric Brun9b3009b2012-10-05 11:55:06 +020014512no-sslv3
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014513 This option disables support for SSLv3 when SSL is used to communicate with
14514 the server. Note that SSLv2 is disabled in the code and cannot be enabled
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014515 using any configuration option. Use "ssl-min-ver" and "ssl-max-ver" instead.
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014516
Emmanuel Hocdet6cb2d1e2017-03-30 14:43:31 +020014517 Supported in default-server: No
14518
Emeric Brunf9c5c472012-10-11 15:28:34 +020014519no-tls-tickets
14520 This setting is only available when support for OpenSSL was built in. It
14521 disables the stateless session resumption (RFC 5077 TLS Ticket
14522 extension) and force to use stateful session resumption. Stateless
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014523 session resumption is more expensive in CPU usage for servers. This option
14524 is also available on global statement "ssl-default-server-options".
Lukas Tribusbdb386d2020-03-10 00:56:09 +010014525 The TLS ticket mechanism is only used up to TLS 1.2.
14526 Forward Secrecy is compromised with TLS tickets, unless ticket keys
14527 are periodically rotated (via reload or by using "tls-ticket-keys").
Frédéric Lécailled2376272017-03-21 18:52:12 +010014528 See also "tls-tickets".
Emeric Brunf9c5c472012-10-11 15:28:34 +020014529
Emeric Brun9b3009b2012-10-05 11:55:06 +020014530no-tlsv10
Emeric Brun8694b9a2012-10-05 14:39:07 +020014531 This option disables support for TLSv1.0 when SSL is used to communicate with
Emeric Brunf5da4932012-09-28 19:42:54 +020014532 the server. Note that SSLv2 is disabled in the code and cannot be enabled
14533 using any configuration option. TLSv1 is more expensive than SSLv3 so it
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014534 often makes sense to disable it when communicating with local servers. This
14535 option is also available on global statement "ssl-default-server-options".
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014536 Use "ssl-min-ver" and "ssl-max-ver" instead.
Willy Tarreau763a95b2012-10-04 23:15:39 +020014537
Emmanuel Hocdet6cb2d1e2017-03-30 14:43:31 +020014538 Supported in default-server: No
14539
Emeric Brun9b3009b2012-10-05 11:55:06 +020014540no-tlsv11
Emeric Brun8694b9a2012-10-05 14:39:07 +020014541 This option disables support for TLSv1.1 when SSL is used to communicate with
Emeric Brunf5da4932012-09-28 19:42:54 +020014542 the server. Note that SSLv2 is disabled in the code and cannot be enabled
14543 using any configuration option. TLSv1 is more expensive than SSLv3 so it
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014544 often makes sense to disable it when communicating with local servers. This
14545 option is also available on global statement "ssl-default-server-options".
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014546 Use "ssl-min-ver" and "ssl-max-ver" instead.
Willy Tarreau763a95b2012-10-04 23:15:39 +020014547
Emmanuel Hocdet6cb2d1e2017-03-30 14:43:31 +020014548 Supported in default-server: No
14549
Emeric Brun9b3009b2012-10-05 11:55:06 +020014550no-tlsv12
Emeric Brun8694b9a2012-10-05 14:39:07 +020014551 This option disables support for TLSv1.2 when SSL is used to communicate with
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014552 the server. Note that SSLv2 is disabled in the code and cannot be enabled
14553 using any configuration option. TLSv1 is more expensive than SSLv3 so it
Emeric Brun2c86cbf2014-10-30 15:56:50 +010014554 often makes sense to disable it when communicating with local servers. This
14555 option is also available on global statement "ssl-default-server-options".
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014556 Use "ssl-min-ver" and "ssl-max-ver" instead.
Emmanuel Hocdet42fb9802017-03-30 19:29:39 +020014557
14558 Supported in default-server: No
14559
14560no-tlsv13
14561 This option disables support for TLSv1.3 when SSL is used to communicate with
14562 the server. Note that SSLv2 is disabled in the code and cannot be enabled
14563 using any configuration option. TLSv1 is more expensive than SSLv3 so it
14564 often makes sense to disable it when communicating with local servers. This
14565 option is also available on global statement "ssl-default-server-options".
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014566 Use "ssl-min-ver" and "ssl-max-ver" instead.
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014567
Emmanuel Hocdet6cb2d1e2017-03-30 14:43:31 +020014568 Supported in default-server: No
14569
Frédéric Lécailled2376272017-03-21 18:52:12 +010014570no-verifyhost
14571 This option may be used as "server" setting to reset any "verifyhost"
14572 setting which would have been inherited from "default-server" directive as
14573 default value.
14574 It may also be used as "default-server" setting to reset any previous
14575 "default-server" "verifyhost" setting.
Willy Tarreau763a95b2012-10-04 23:15:39 +020014576
Frédéric Lécaille1b9423d2019-07-04 14:19:06 +020014577no-tfo
14578 This option may be used as "server" setting to reset any "tfo"
14579 setting which would have been inherited from "default-server" directive as
14580 default value.
14581 It may also be used as "default-server" setting to reset any previous
14582 "default-server" "tfo" setting.
14583
Simon Hormanfa461682011-06-25 09:39:49 +090014584non-stick
14585 Never add connections allocated to this sever to a stick-table.
14586 This may be used in conjunction with backup to ensure that
14587 stick-table persistence is disabled for backup servers.
14588
Olivier Houchardc7566002018-11-20 23:33:50 +010014589npn <protocols>
14590 This enables the NPN TLS extension and advertises the specified protocol list
14591 as supported on top of NPN. The protocol list consists in a comma-delimited
14592 list of protocol names, for instance: "http/1.1,http/1.0" (without quotes).
John Roeslerfb2fce12019-07-10 15:45:51 -050014593 This requires that the SSL library is built with support for TLS extensions
Olivier Houchardc7566002018-11-20 23:33:50 +010014594 enabled (check with haproxy -vv). Note that the NPN extension has been
14595 replaced with the ALPN extension (see the "alpn" keyword), though this one is
14596 only available starting with OpenSSL 1.0.2.
14597
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014598observe <mode>
14599 This option enables health adjusting based on observing communication with
14600 the server. By default this functionality is disabled and enabling it also
14601 requires to enable health checks. There are two supported modes: "layer4" and
14602 "layer7". In layer4 mode, only successful/unsuccessful tcp connections are
14603 significant. In layer7, which is only allowed for http proxies, responses
14604 received from server are verified, like valid/wrong http code, unparsable
Willy Tarreau150d1462012-03-10 08:19:02 +010014605 headers, a timeout, etc. Valid status codes include 100 to 499, 501 and 505.
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014606
14607 See also the "check", "on-error" and "error-limit".
14608
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014609on-error <mode>
Krzysztof Piotr Oledzki97f07b82009-12-15 22:31:24 +010014610 Select what should happen when enough consecutive errors are detected.
14611 Currently, four modes are available:
14612 - fastinter: force fastinter
14613 - fail-check: simulate a failed check, also forces fastinter (default)
14614 - sudden-death: simulate a pre-fatal failed health check, one more failed
14615 check will mark a server down, forces fastinter
14616 - mark-down: mark the server immediately down and force fastinter
14617
14618 See also the "check", "observe" and "error-limit".
14619
Simon Hormane0d1bfb2011-06-21 14:34:58 +090014620on-marked-down <action>
14621 Modify what occurs when a server is marked down.
14622 Currently one action is available:
Justin Karnegeseb2c24a2012-05-24 15:28:52 -070014623 - shutdown-sessions: Shutdown peer sessions. When this setting is enabled,
14624 all connections to the server are immediately terminated when the server
14625 goes down. It might be used if the health check detects more complex cases
14626 than a simple connection status, and long timeouts would cause the service
14627 to remain unresponsive for too long a time. For instance, a health check
14628 might detect that a database is stuck and that there's no chance to reuse
14629 existing connections anymore. Connections killed this way are logged with
14630 a 'D' termination code (for "Down").
Simon Hormane0d1bfb2011-06-21 14:34:58 +090014631
14632 Actions are disabled by default
14633
Justin Karnegeseb2c24a2012-05-24 15:28:52 -070014634on-marked-up <action>
14635 Modify what occurs when a server is marked up.
14636 Currently one action is available:
14637 - shutdown-backup-sessions: Shutdown sessions on all backup servers. This is
14638 done only if the server is not in backup state and if it is not disabled
14639 (it must have an effective weight > 0). This can be used sometimes to force
14640 an active server to take all the traffic back after recovery when dealing
Davor Ocelice9ed2812017-12-25 17:49:28 +010014641 with long sessions (e.g. LDAP, SQL, ...). Doing this can cause more trouble
14642 than it tries to solve (e.g. incomplete transactions), so use this feature
Justin Karnegeseb2c24a2012-05-24 15:28:52 -070014643 with extreme care. Sessions killed because a server comes up are logged
14644 with an 'U' termination code (for "Up").
14645
14646 Actions are disabled by default
14647
Willy Tarreau2f3f4d32020-07-01 07:43:51 +020014648pool-low-conn <max>
14649 Set a low threshold on the number of idling connections for a server, below
14650 which a thread will not try to steal a connection from another thread. This
14651 can be useful to improve CPU usage patterns in scenarios involving many very
14652 fast servers, in order to ensure all threads will keep a few idle connections
14653 all the time instead of letting them accumulate over one thread and migrating
14654 them from thread to thread. Typical values of twice the number of threads
14655 seem to show very good performance already with sub-millisecond response
14656 times. The default is zero, indicating that any idle connection can be used
14657 at any time. It is the recommended setting for normal use. This only applies
14658 to connections that can be shared according to the same principles as those
Willy Tarreau0784db82021-02-19 11:45:22 +010014659 applying to "http-reuse". In case connection sharing between threads would
14660 be disabled via "tune.idle-pool.shared", it can become very important to use
14661 this setting to make sure each thread always has a few connections, or the
14662 connection reuse rate will decrease as thread count increases.
Willy Tarreau2f3f4d32020-07-01 07:43:51 +020014663
Olivier Houchard006e3102018-12-10 18:30:32 +010014664pool-max-conn <max>
14665 Set the maximum number of idling connections for a server. -1 means unlimited
14666 connections, 0 means no idle connections. The default is -1. When idle
14667 connections are enabled, orphaned idle connections which do not belong to any
14668 client session anymore are moved to a dedicated pool so that they remain
14669 usable by future clients. This only applies to connections that can be shared
14670 according to the same principles as those applying to "http-reuse".
14671
Olivier Houchardb7b3faa2018-12-14 18:15:36 +010014672pool-purge-delay <delay>
14673 Sets the delay to start purging idle connections. Each <delay> interval, half
Olivier Houcharda56eebf2019-03-19 16:44:02 +010014674 of the idle connections are closed. 0 means we don't keep any idle connection.
Willy Tarreaufb553652019-06-04 14:06:31 +020014675 The default is 5s.
Olivier Houchardb7b3faa2018-12-14 18:15:36 +010014676
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014677port <port>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014678 Using the "port" parameter, it becomes possible to use a different port to
William Dauchy4858fb22021-02-03 22:30:09 +010014679 send health-checks or to probe the agent-check. On some servers, it may be
14680 desirable to dedicate a port to a specific component able to perform complex
14681 tests which are more suitable to health-checks than the application. It is
14682 common to run a simple script in inetd for instance. This parameter is
14683 ignored if the "check" parameter is not set. See also the "addr" parameter.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014684
Christopher Faulet8ed0a3e2018-04-10 14:45:45 +020014685proto <name>
Christopher Faulet8ed0a3e2018-04-10 14:45:45 +020014686 Forces the multiplexer's protocol to use for the outgoing connections to this
14687 server. It must be compatible with the mode of the backend (TCP or HTTP). It
14688 must also be usable on the backend side. The list of available protocols is
Christopher Faulet982e17d2021-03-26 14:44:18 +010014689 reported in haproxy -vv.The protocols properties are reported : the mode
14690 (TCP/HTTP), the side (FE/BE), the mux name and its flags.
14691
14692 Some protocols report errors on aborts (flag=CLEAN_ABRT). Some others are
14693 subject to the head-of-line blocking on server side (flag=HOL_RISK). Finally
14694 some protocols don't support upgrades (flag=NO_UPG). The HTX compatibility is
14695 also reported (flag=HTX).
14696
14697 Here are the protocols that may be used as argument to a "proto" directive on
14698 a server line :
14699
14700 h2 : mode=HTTP side=FE|BE mux=H2 flags=HTX|CLEAN_ABRT|HOL_RISK|NO_UPG
14701 fcgi : mode=HTTP side=BE mux=FCGI flags=HTX|HOL_RISK|NO_UPG
14702 h1 : mode=HTTP side=FE|BE mux=H1 flags=HTX|NO_UPG
14703 none : mode=TCP side=FE|BE mux=PASS flags=NO_UPG
14704
Daniel Corbett67a82712020-07-06 23:01:19 -040014705 Idea behind this option is to bypass the selection of the best multiplexer's
Christopher Faulet8ed0a3e2018-04-10 14:45:45 +020014706 protocol for all connections established to this server.
14707
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014708redir <prefix>
14709 The "redir" parameter enables the redirection mode for all GET and HEAD
14710 requests addressing this server. This means that instead of having HAProxy
14711 forward the request to the server, it will send an "HTTP 302" response with
14712 the "Location" header composed of this prefix immediately followed by the
14713 requested URI beginning at the leading '/' of the path component. That means
14714 that no trailing slash should be used after <prefix>. All invalid requests
14715 will be rejected, and all non-GET or HEAD requests will be normally served by
14716 the server. Note that since the response is completely forged, no header
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010014717 mangling nor cookie insertion is possible in the response. However, cookies in
Davor Ocelice9ed2812017-12-25 17:49:28 +010014718 requests are still analyzed, making this solution completely usable to direct
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014719 users to a remote location in case of local disaster. Main use consists in
14720 increasing bandwidth for static servers by having the clients directly
14721 connect to them. Note: never use a relative location here, it would cause a
14722 loop between the client and HAProxy!
14723
14724 Example : server srv1 192.168.1.1:80 redir http://image1.mydomain.com check
14725
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014726rise <count>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014727 The "rise" parameter states that a server will be considered as operational
14728 after <count> consecutive successful health checks. This value defaults to 2
14729 if unspecified. See also the "check", "inter" and "fall" parameters.
14730
Baptiste Assmann8e2d9432018-06-22 15:04:43 +020014731resolve-opts <option>,<option>,...
14732 Comma separated list of options to apply to DNS resolution linked to this
14733 server.
14734
14735 Available options:
14736
14737 * allow-dup-ip
14738 By default, HAProxy prevents IP address duplication in a backend when DNS
14739 resolution at runtime is in operation.
14740 That said, for some cases, it makes sense that two servers (in the same
14741 backend, being resolved by the same FQDN) have the same IP address.
14742 For such case, simply enable this option.
14743 This is the opposite of prevent-dup-ip.
14744
Daniel Corbettf8716912019-11-17 09:48:56 -050014745 * ignore-weight
14746 Ignore any weight that is set within an SRV record. This is useful when
14747 you would like to control the weights using an alternate method, such as
14748 using an "agent-check" or through the runtime api.
14749
Baptiste Assmann8e2d9432018-06-22 15:04:43 +020014750 * prevent-dup-ip
14751 Ensure HAProxy's default behavior is enforced on a server: prevent re-using
14752 an IP address already set to a server in the same backend and sharing the
14753 same fqdn.
14754 This is the opposite of allow-dup-ip.
14755
14756 Example:
14757 backend b_myapp
14758 default-server init-addr none resolvers dns
14759 server s1 myapp.example.com:80 check resolve-opts allow-dup-ip
14760 server s2 myapp.example.com:81 check resolve-opts allow-dup-ip
14761
14762 With the option allow-dup-ip set:
14763 * if the nameserver returns a single IP address, then both servers will use
14764 it
14765 * If the nameserver returns 2 IP addresses, then each server will pick up a
14766 different address
14767
14768 Default value: not set
14769
Baptiste Assmann1fa66662015-04-14 00:28:47 +020014770resolve-prefer <family>
14771 When DNS resolution is enabled for a server and multiple IP addresses from
14772 different families are returned, HAProxy will prefer using an IP address
14773 from the family mentioned in the "resolve-prefer" parameter.
14774 Available families: "ipv4" and "ipv6"
14775
Baptiste Assmannc4aabae2015-08-04 22:43:06 +020014776 Default value: ipv6
14777
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +020014778 Example:
14779
14780 server s1 app1.domain.com:80 resolvers mydns resolve-prefer ipv6
Baptiste Assmann1fa66662015-04-14 00:28:47 +020014781
Thierry Fournierac88cfe2016-02-17 22:05:30 +010014782resolve-net <network>[,<network[,...]]
John Roeslerfb2fce12019-07-10 15:45:51 -050014783 This option prioritizes the choice of an ip address matching a network. This is
Thierry Fournierac88cfe2016-02-17 22:05:30 +010014784 useful with clouds to prefer a local ip. In some cases, a cloud high
Tim Düsterhus4896c442016-11-29 02:15:19 +010014785 availability service can be announced with many ip addresses on many
Davor Ocelice9ed2812017-12-25 17:49:28 +010014786 different datacenters. The latency between datacenter is not negligible, so
14787 this patch permits to prefer a local datacenter. If no address matches the
Thierry Fournierac88cfe2016-02-17 22:05:30 +010014788 configured network, another address is selected.
14789
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +020014790 Example:
14791
14792 server s1 app1.domain.com:80 resolvers mydns resolve-net 10.0.0.0/8
Thierry Fournierac88cfe2016-02-17 22:05:30 +010014793
Baptiste Assmann1fa66662015-04-14 00:28:47 +020014794resolvers <id>
14795 Points to an existing "resolvers" section to resolve current server's
14796 hostname.
14797
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +020014798 Example:
14799
14800 server s1 app1.domain.com:80 check resolvers mydns
Baptiste Assmann1fa66662015-04-14 00:28:47 +020014801
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +020014802 See also section 5.3
Baptiste Assmann1fa66662015-04-14 00:28:47 +020014803
Willy Tarreau5ab04ec2011-03-20 10:32:26 +010014804send-proxy
14805 The "send-proxy" parameter enforces use of the PROXY protocol over any
14806 connection established to this server. The PROXY protocol informs the other
14807 end about the layer 3/4 addresses of the incoming connection, so that it can
14808 know the client's address or the public address it accessed to, whatever the
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010014809 upper layer protocol. For connections accepted by an "accept-proxy" or
14810 "accept-netscaler-cip" listener, the advertised address will be used. Only
14811 TCPv4 and TCPv6 address families are supported. Other families such as
14812 Unix sockets, will report an UNKNOWN family. Servers using this option can
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014813 fully be chained to another instance of HAProxy listening with an
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010014814 "accept-proxy" setting. This setting must not be used if the server isn't
14815 aware of the protocol. When health checks are sent to the server, the PROXY
14816 protocol is automatically used when this option is set, unless there is an
14817 explicit "port" or "addr" directive, in which case an explicit
14818 "check-send-proxy" directive would also be needed to use the PROXY protocol.
Frédéric Lécailled2376272017-03-21 18:52:12 +010014819 See also the "no-send-proxy" option of this section and "accept-proxy" and
14820 "accept-netscaler-cip" option of the "bind" keyword.
Willy Tarreau5ab04ec2011-03-20 10:32:26 +010014821
David Safb76832014-05-08 23:42:08 -040014822send-proxy-v2
14823 The "send-proxy-v2" parameter enforces use of the PROXY protocol version 2
14824 over any connection established to this server. The PROXY protocol informs
14825 the other end about the layer 3/4 addresses of the incoming connection, so
14826 that it can know the client's address or the public address it accessed to,
Emmanuel Hocdet404d9782017-10-24 10:55:14 +020014827 whatever the upper layer protocol. It also send ALPN information if an alpn
14828 have been negotiated. This setting must not be used if the server isn't aware
14829 of this version of the protocol. See also the "no-send-proxy-v2" option of
14830 this section and send-proxy" option of the "bind" keyword.
David Safb76832014-05-08 23:42:08 -040014831
Emmanuel Hocdetf643b802018-02-01 15:20:32 +010014832proxy-v2-options <option>[,<option>]*
Tim Duesterhuscf6e0c82020-03-13 12:34:24 +010014833 The "proxy-v2-options" parameter add options to send in PROXY protocol
14834 version 2 when "send-proxy-v2" is used. Options available are:
14835
14836 - ssl : See also "send-proxy-v2-ssl".
14837 - cert-cn : See also "send-proxy-v2-ssl-cn".
14838 - ssl-cipher: Name of the used cipher.
14839 - cert-sig : Signature algorithm of the used certificate.
14840 - cert-key : Key algorithm of the used certificate
14841 - authority : Host name value passed by the client (only SNI from a TLS
14842 connection is supported).
14843 - crc32c : Checksum of the PROXYv2 header.
14844 - unique-id : Send a unique ID generated using the frontend's
14845 "unique-id-format" within the PROXYv2 header.
14846 This unique-id is primarily meant for "mode tcp". It can
14847 lead to unexpected results in "mode http", because the
14848 generated unique ID is also used for the first HTTP request
14849 within a Keep-Alive connection.
Emmanuel Hocdetf643b802018-02-01 15:20:32 +010014850
David Safb76832014-05-08 23:42:08 -040014851send-proxy-v2-ssl
14852 The "send-proxy-v2-ssl" parameter enforces use of the PROXY protocol version
14853 2 over any connection established to this server. The PROXY protocol informs
14854 the other end about the layer 3/4 addresses of the incoming connection, so
14855 that it can know the client's address or the public address it accessed to,
14856 whatever the upper layer protocol. In addition, the SSL information extension
14857 of the PROXY protocol is added to the PROXY protocol header. This setting
14858 must not be used if the server isn't aware of this version of the protocol.
Frédéric Lécailled2376272017-03-21 18:52:12 +010014859 See also the "no-send-proxy-v2-ssl" option of this section and the
14860 "send-proxy-v2" option of the "bind" keyword.
David Safb76832014-05-08 23:42:08 -040014861
14862send-proxy-v2-ssl-cn
14863 The "send-proxy-v2-ssl" parameter enforces use of the PROXY protocol version
14864 2 over any connection established to this server. The PROXY protocol informs
14865 the other end about the layer 3/4 addresses of the incoming connection, so
14866 that it can know the client's address or the public address it accessed to,
14867 whatever the upper layer protocol. In addition, the SSL information extension
14868 of the PROXY protocol, along along with the Common Name from the subject of
14869 the client certificate (if any), is added to the PROXY protocol header. This
14870 setting must not be used if the server isn't aware of this version of the
Davor Ocelice9ed2812017-12-25 17:49:28 +010014871 protocol. See also the "no-send-proxy-v2-ssl-cn" option of this section and
14872 the "send-proxy-v2" option of the "bind" keyword.
David Safb76832014-05-08 23:42:08 -040014873
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010014874slowstart <start_time_in_ms>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014875 The "slowstart" parameter for a server accepts a value in milliseconds which
14876 indicates after how long a server which has just come back up will run at
14877 full speed. Just as with every other time-based parameter, it can be entered
14878 in any other explicit unit among { us, ms, s, m, h, d }. The speed grows
14879 linearly from 0 to 100% during this time. The limitation applies to two
14880 parameters :
14881
14882 - maxconn: the number of connections accepted by the server will grow from 1
14883 to 100% of the usual dynamic limit defined by (minconn,maxconn,fullconn).
14884
14885 - weight: when the backend uses a dynamic weighted algorithm, the weight
14886 grows linearly from 1 to 100%. In this case, the weight is updated at every
14887 health-check. For this reason, it is important that the "inter" parameter
14888 is smaller than the "slowstart", in order to maximize the number of steps.
14889
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014890 The slowstart never applies when HAProxy starts, otherwise it would cause
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014891 trouble to running servers. It only applies when a server has been previously
14892 seen as failed.
14893
Willy Tarreau732eac42015-07-09 11:40:25 +020014894sni <expression>
14895 The "sni" parameter evaluates the sample fetch expression, converts it to a
14896 string and uses the result as the host name sent in the SNI TLS extension to
14897 the server. A typical use case is to send the SNI received from the client in
14898 a bridged HTTPS scenario, using the "ssl_fc_sni" sample fetch for the
Willy Tarreau2ab88672017-07-05 18:23:03 +020014899 expression, though alternatives such as req.hdr(host) can also make sense. If
14900 "verify required" is set (which is the recommended setting), the resulting
Willy Tarreauad92a9a2017-07-28 11:38:41 +020014901 name will also be matched against the server certificate's names. See the
Jérôme Magninb36a6d22018-12-09 16:03:40 +010014902 "verify" directive for more details. If you want to set a SNI for health
14903 checks, see the "check-sni" directive for more details.
Willy Tarreau732eac42015-07-09 11:40:25 +020014904
Willy Tarreauc6f4ce82009-06-10 11:09:37 +020014905source <addr>[:<pl>[-<ph>]] [usesrc { <addr2>[:<port2>] | client | clientip } ]
Willy Tarreaubce70882009-09-07 11:51:47 +020014906source <addr>[:<port>] [usesrc { <addr2>[:<port2>] | hdr_ip(<hdr>[,<occ>]) } ]
Willy Tarreauc6f4ce82009-06-10 11:09:37 +020014907source <addr>[:<pl>[-<ph>]] [interface <name>] ...
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014908 The "source" parameter sets the source address which will be used when
14909 connecting to the server. It follows the exact same parameters and principle
14910 as the backend "source" keyword, except that it only applies to the server
14911 referencing it. Please consult the "source" keyword for details.
14912
Willy Tarreauc6f4ce82009-06-10 11:09:37 +020014913 Additionally, the "source" statement on a server line allows one to specify a
14914 source port range by indicating the lower and higher bounds delimited by a
14915 dash ('-'). Some operating systems might require a valid IP address when a
14916 source port range is specified. It is permitted to have the same IP/range for
14917 several servers. Doing so makes it possible to bypass the maximum of 64k
14918 total concurrent connections. The limit will then reach 64k connections per
14919 server.
14920
Lukas Tribus7d56c6d2016-09-13 09:51:15 +000014921 Since Linux 4.2/libc 2.23 IP_BIND_ADDRESS_NO_PORT is set for connections
14922 specifying the source address without port(s).
14923
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014924ssl
Willy Tarreau44f65392013-06-25 07:56:20 +020014925 This option enables SSL ciphering on outgoing connections to the server. It
14926 is critical to verify server certificates using "verify" when using SSL to
14927 connect to servers, otherwise the communication is prone to trivial man in
14928 the-middle attacks rendering SSL useless. When this option is used, health
14929 checks are automatically sent in SSL too unless there is a "port" or an
14930 "addr" directive indicating the check should be sent to a different location.
Frédéric Lécailled2376272017-03-21 18:52:12 +010014931 See the "no-ssl" to disable "ssl" option and "check-ssl" option to force
14932 SSL health checks.
Willy Tarreau763a95b2012-10-04 23:15:39 +020014933
Emmanuel Hocdete1c722b2017-03-31 15:02:54 +020014934ssl-max-ver [ SSLv3 | TLSv1.0 | TLSv1.1 | TLSv1.2 | TLSv1.3 ]
14935 This option enforces use of <version> or lower when SSL is used to communicate
14936 with the server. This option is also available on global statement
14937 "ssl-default-server-options". See also "ssl-min-ver".
14938
14939ssl-min-ver [ SSLv3 | TLSv1.0 | TLSv1.1 | TLSv1.2 | TLSv1.3 ]
14940 This option enforces use of <version> or upper when SSL is used to communicate
14941 with the server. This option is also available on global statement
14942 "ssl-default-server-options". See also "ssl-max-ver".
14943
Frédéric Lécailled2376272017-03-21 18:52:12 +010014944ssl-reuse
14945 This option may be used as "server" setting to reset any "no-ssl-reuse"
14946 setting which would have been inherited from "default-server" directive as
14947 default value.
14948 It may also be used as "default-server" setting to reset any previous
14949 "default-server" "no-ssl-reuse" setting.
14950
14951stick
14952 This option may be used as "server" setting to reset any "non-stick"
14953 setting which would have been inherited from "default-server" directive as
14954 default value.
14955 It may also be used as "default-server" setting to reset any previous
14956 "default-server" "non-stick" setting.
Willy Tarreaua0ee1d02012-09-10 09:01:23 +020014957
Alexander Liu2a54bb72019-05-22 19:44:48 +080014958socks4 <addr>:<port>
John Roeslerfb2fce12019-07-10 15:45:51 -050014959 This option enables upstream socks4 tunnel for outgoing connections to the
Alexander Liu2a54bb72019-05-22 19:44:48 +080014960 server. Using this option won't force the health check to go via socks4 by
14961 default. You will have to use the keyword "check-via-socks4" to enable it.
14962
Willy Tarreau163d4622015-10-13 16:16:41 +020014963tcp-ut <delay>
14964 Sets the TCP User Timeout for all outgoing connections to this server. This
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014965 option is available on Linux since version 2.6.37. It allows HAProxy to
Willy Tarreau163d4622015-10-13 16:16:41 +020014966 configure a timeout for sockets which contain data not receiving an
Davor Ocelice9ed2812017-12-25 17:49:28 +010014967 acknowledgment for the configured delay. This is especially useful on
Willy Tarreau163d4622015-10-13 16:16:41 +020014968 long-lived connections experiencing long idle periods such as remote
14969 terminals or database connection pools, where the client and server timeouts
14970 must remain high to allow a long period of idle, but where it is important to
14971 detect that the server has disappeared in order to release all resources
14972 associated with its connection (and the client's session). One typical use
14973 case is also to force dead server connections to die when health checks are
14974 too slow or during a soft reload since health checks are then disabled. The
14975 argument is a delay expressed in milliseconds by default. This only works for
14976 regular TCP connections, and is ignored for other protocols.
14977
Willy Tarreau034c88c2017-01-23 23:36:45 +010014978tfo
14979 This option enables using TCP fast open when connecting to servers, on
14980 systems that support it (currently only the Linux kernel >= 4.11).
14981 See the "tfo" bind option for more information about TCP fast open.
14982 Please note that when using tfo, you should also use the "conn-failure",
Daniel Corbett9f0843f2021-05-08 10:50:37 -040014983 "empty-response" and "response-timeout" keywords for "retry-on", or HAProxy
Frédéric Lécaille1b9423d2019-07-04 14:19:06 +020014984 won't be able to retry the connection on failure. See also "no-tfo".
Willy Tarreau034c88c2017-01-23 23:36:45 +010014985
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014986track [<proxy>/]<server>
Willy Tarreau32091232014-05-16 13:52:00 +020014987 This option enables ability to set the current state of the server by tracking
14988 another one. It is possible to track a server which itself tracks another
14989 server, provided that at the end of the chain, a server has health checks
14990 enabled. If <proxy> is omitted the current one is used. If disable-on-404 is
Willy Tarreauc57f0e22009-05-10 13:12:33 +020014991 used, it has to be enabled on both proxies.
14992
Frédéric Lécailled2376272017-03-21 18:52:12 +010014993tls-tickets
14994 This option may be used as "server" setting to reset any "no-tls-tickets"
14995 setting which would have been inherited from "default-server" directive as
14996 default value.
Lukas Tribusbdb386d2020-03-10 00:56:09 +010014997 The TLS ticket mechanism is only used up to TLS 1.2.
14998 Forward Secrecy is compromised with TLS tickets, unless ticket keys
14999 are periodically rotated (via reload or by using "tls-ticket-keys").
Frédéric Lécailled2376272017-03-21 18:52:12 +010015000 It may also be used as "default-server" setting to reset any previous
Bjoern Jacke5ab7eb62020-02-13 14:16:16 +010015001 "default-server" "no-tls-tickets" setting.
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010015002
Emeric Brunef42d922012-10-11 16:11:36 +020015003verify [none|required]
15004 This setting is only available when support for OpenSSL was built in. If set
Emeric Brun850efd52014-01-29 12:24:34 +010015005 to 'none', server certificate is not verified. In the other case, The
Willy Tarreauad92a9a2017-07-28 11:38:41 +020015006 certificate provided by the server is verified using CAs from 'ca-file' and
15007 optional CRLs from 'crl-file' after having checked that the names provided in
Davor Ocelice9ed2812017-12-25 17:49:28 +010015008 the certificate's subject and subjectAlternateNames attributes match either
Willy Tarreauad92a9a2017-07-28 11:38:41 +020015009 the name passed using the "sni" directive, or if not provided, the static
15010 host name passed using the "verifyhost" directive. When no name is found, the
15011 certificate's names are ignored. For this reason, without SNI it's important
15012 to use "verifyhost". On verification failure the handshake is aborted. It is
15013 critically important to verify server certificates when using SSL to connect
15014 to servers, otherwise the communication is prone to trivial man-in-the-middle
15015 attacks rendering SSL totally useless. Unless "ssl_server_verify" appears in
15016 the global section, "verify" is set to "required" by default.
Emeric Brunef42d922012-10-11 16:11:36 +020015017
Evan Broderbe554312013-06-27 00:05:25 -070015018verifyhost <hostname>
15019 This setting is only available when support for OpenSSL was built in, and
Willy Tarreauad92a9a2017-07-28 11:38:41 +020015020 only takes effect if 'verify required' is also specified. This directive sets
15021 a default static hostname to check the server's certificate against when no
15022 SNI was used to connect to the server. If SNI is not used, this is the only
15023 way to enable hostname verification. This static hostname, when set, will
15024 also be used for health checks (which cannot provide an SNI value). If none
15025 of the hostnames in the certificate match the specified hostname, the
15026 handshake is aborted. The hostnames in the server-provided certificate may
15027 include wildcards. See also "verify", "sni" and "no-verifyhost" options.
Evan Broderbe554312013-06-27 00:05:25 -070015028
Krzysztof Piotr Oledzkic53601c2010-01-06 10:50:42 +010015029weight <weight>
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015030 The "weight" parameter is used to adjust the server's weight relative to
15031 other servers. All servers will receive a load proportional to their weight
15032 relative to the sum of all weights, so the higher the weight, the higher the
Willy Tarreau6704d672009-06-15 10:56:05 +020015033 load. The default weight is 1, and the maximal value is 256. A value of 0
15034 means the server will not participate in load-balancing but will still accept
15035 persistent connections. If this parameter is used to distribute the load
15036 according to server's capacity, it is recommended to start with values which
15037 can both grow and shrink, for instance between 10 and 100 to leave enough
15038 room above and below for later adjustments.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015039
15040
Cyril Bonté46175dd2015-07-02 22:45:32 +0200150415.3. Server IP address resolution using DNS
15042-------------------------------------------
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015043
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015044HAProxy allows using a host name on the server line to retrieve its IP address
15045using name servers. By default, HAProxy resolves the name when parsing the
Thayne McCombscdbcca92021-01-07 21:24:41 -070015046configuration file, at startup and cache the result for the process's life.
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015047This is not sufficient in some cases, such as in Amazon where a server's IP
15048can change after a reboot or an ELB Virtual IP can change based on current
15049workload.
15050This chapter describes how HAProxy can be configured to process server's name
15051resolution at run time.
15052Whether run time server name resolution has been enable or not, HAProxy will
15053carry on doing the first resolution when parsing the configuration.
15054
15055
Cyril Bonté46175dd2015-07-02 22:45:32 +0200150565.3.1. Global overview
15057----------------------
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015058
15059As we've seen in introduction, name resolution in HAProxy occurs at two
15060different steps of the process life:
15061
15062 1. when starting up, HAProxy parses the server line definition and matches a
15063 host name. It uses libc functions to get the host name resolved. This
15064 resolution relies on /etc/resolv.conf file.
15065
Christopher Faulet67957bd2017-09-27 11:00:59 +020015066 2. at run time, HAProxy performs periodically name resolutions for servers
15067 requiring DNS resolutions.
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015068
15069A few other events can trigger a name resolution at run time:
15070 - when a server's health check ends up in a connection timeout: this may be
15071 because the server has a new IP address. So we need to trigger a name
15072 resolution to know this new IP.
15073
Christopher Faulet67957bd2017-09-27 11:00:59 +020015074When using resolvers, the server name can either be a hostname, or a SRV label.
Davor Ocelice9ed2812017-12-25 17:49:28 +010015075HAProxy considers anything that starts with an underscore as a SRV label. If a
Christopher Faulet67957bd2017-09-27 11:00:59 +020015076SRV label is specified, then the corresponding SRV records will be retrieved
15077from the DNS server, and the provided hostnames will be used. The SRV label
Daniel Corbett9f0843f2021-05-08 10:50:37 -040015078will be checked periodically, and if any server are added or removed, HAProxy
Christopher Faulet67957bd2017-09-27 11:00:59 +020015079will automatically do the same.
Olivier Houchardecfa18d2017-08-07 17:30:03 +020015080
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015081A few things important to notice:
John Roeslerfb2fce12019-07-10 15:45:51 -050015082 - all the name servers are queried in the meantime. HAProxy will process the
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015083 first valid response.
15084
15085 - a resolution is considered as invalid (NX, timeout, refused), when all the
15086 servers return an error.
15087
15088
Cyril Bonté46175dd2015-07-02 22:45:32 +0200150895.3.2. The resolvers section
15090----------------------------
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015091
15092This section is dedicated to host information related to name resolution in
Christopher Faulet67957bd2017-09-27 11:00:59 +020015093HAProxy. There can be as many as resolvers section as needed. Each section can
15094contain many name servers.
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015095
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015096When multiple name servers are configured in a resolvers section, then HAProxy
15097uses the first valid response. In case of invalid responses, only the last one
15098is treated. Purpose is to give the chance to a slow server to deliver a valid
15099answer after a fast faulty or outdated server.
15100
15101When each server returns a different error type, then only the last error is
Christopher Faulet67957bd2017-09-27 11:00:59 +020015102used by HAProxy. The following processing is applied on this error:
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015103
Christopher Faulet67957bd2017-09-27 11:00:59 +020015104 1. HAProxy retries the same DNS query with a new query type. The A queries are
15105 switch to AAAA or the opposite. SRV queries are not concerned here. Timeout
15106 errors are also excluded.
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015107
Christopher Faulet67957bd2017-09-27 11:00:59 +020015108 2. When the fallback on the query type was done (or not applicable), HAProxy
15109 retries the original DNS query, with the preferred query type.
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015110
Christopher Faulet67957bd2017-09-27 11:00:59 +020015111 3. HAProxy retries previous steps <resolve_retires> times. If no valid
15112 response is received after that, it stops the DNS resolution and reports
15113 the error.
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015114
Christopher Faulet67957bd2017-09-27 11:00:59 +020015115For example, with 2 name servers configured in a resolvers section, the
15116following scenarios are possible:
15117
15118 - First response is valid and is applied directly, second response is
15119 ignored
15120
15121 - First response is invalid and second one is valid, then second response is
15122 applied
15123
15124 - First response is a NX domain and second one a truncated response, then
15125 HAProxy retries the query with a new type
15126
15127 - First response is a NX domain and second one is a timeout, then HAProxy
15128 retries the query with a new type
15129
15130 - Query timed out for both name servers, then HAProxy retries it with the
15131 same query type
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015132
Daniel Corbett9f0843f2021-05-08 10:50:37 -040015133As a DNS server may not answer all the IPs in one DNS request, HAProxy keeps
Olivier Houcharda8c6db82017-07-06 18:46:47 +020015134a cache of previous answers, an answer will be considered obsolete after
Christopher Faulet67957bd2017-09-27 11:00:59 +020015135<hold obsolete> seconds without the IP returned.
Olivier Houcharda8c6db82017-07-06 18:46:47 +020015136
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015137
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015138resolvers <resolvers id>
Davor Ocelice9ed2812017-12-25 17:49:28 +010015139 Creates a new name server list labeled <resolvers id>
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015140
15141A resolvers section accept the following parameters:
15142
Baptiste Assmann2af08fe2017-08-14 00:13:01 +020015143accepted_payload_size <nb>
Davor Ocelice9ed2812017-12-25 17:49:28 +010015144 Defines the maximum payload size accepted by HAProxy and announced to all the
Christopher Faulet67957bd2017-09-27 11:00:59 +020015145 name servers configured in this resolvers section.
Baptiste Assmann2af08fe2017-08-14 00:13:01 +020015146 <nb> is in bytes. If not set, HAProxy announces 512. (minimal value defined
15147 by RFC 6891)
15148
Emeric Brun4c751952021-03-08 16:41:29 +010015149 Note: the maximum allowed value is 65535. Recommended value for UDP is
15150 4096 and it is not recommended to exceed 8192 except if you are sure
15151 that your system and network can handle this (over 65507 makes no sense
15152 since is the maximum UDP payload size). If you are using only TCP
15153 nameservers to handle huge DNS responses, you should put this value
15154 to the max: 65535.
Baptiste Assmann9d8dbbc2017-08-18 23:35:08 +020015155
Emeric Brunc8f3e452021-04-07 16:04:54 +020015156nameserver <name> <address>[:port] [param*]
15157 Used to configure a nameserver. <name> of the nameserver should ne unique.
15158 By default the <address> is considered of type datagram. This means if an
15159 IPv4 or IPv6 is configured without special address prefixes (paragraph 11.)
15160 the UDP protocol will be used. If an stream protocol address prefix is used,
15161 the nameserver will be considered as a stream server (TCP for instance) and
15162 "server" parameters found in 5.2 paragraph which are relevant for DNS
15163 resolving will be considered. Note: currently, in TCP mode, 4 queries are
15164 pipelined on the same connections. A batch of idle connections are removed
15165 every 5 seconds. "maxconn" can be configured to limit the amount of those
Emeric Brun56fc5d92021-02-12 20:05:45 +010015166 concurrent connections and TLS should also usable if the server supports.
15167
Ben Draut44e609b2018-05-29 15:40:08 -060015168parse-resolv-conf
15169 Adds all nameservers found in /etc/resolv.conf to this resolvers nameservers
15170 list. Ordered as if each nameserver in /etc/resolv.conf was individually
15171 placed in the resolvers section in place of this directive.
15172
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015173hold <status> <period>
15174 Defines <period> during which the last name resolution should be kept based
15175 on last resolution <status>
Baptiste Assmann987e16d2016-11-02 22:23:31 +010015176 <status> : last name resolution status. Acceptable values are "nx",
Olivier Houcharda8c6db82017-07-06 18:46:47 +020015177 "other", "refused", "timeout", "valid", "obsolete".
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015178 <period> : interval between two successive name resolution when the last
15179 answer was in <status>. It follows the HAProxy time format.
15180 <period> is in milliseconds by default.
15181
Baptiste Assmann686408b2017-08-18 10:15:42 +020015182 Default value is 10s for "valid", 0s for "obsolete" and 30s for others.
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015183
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015184resolve_retries <nb>
15185 Defines the number <nb> of queries to send to resolve a server name before
15186 giving up.
15187 Default value: 3
15188
Baptiste Assmann62b75b42015-09-09 01:11:36 +020015189 A retry occurs on name server timeout or when the full sequence of DNS query
15190 type failover is over and we need to start up from the default ANY query
15191 type.
15192
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015193timeout <event> <time>
15194 Defines timeouts related to name resolution
15195 <event> : the event on which the <time> timeout period applies to.
15196 events available are:
Frédéric Lécaille93d33162019-03-06 09:35:59 +010015197 - resolve : default time to trigger name resolutions when no
15198 other time applied.
Christopher Faulet67957bd2017-09-27 11:00:59 +020015199 Default value: 1s
15200 - retry : time between two DNS queries, when no valid response
Frédéric Lécaille93d33162019-03-06 09:35:59 +010015201 have been received.
Christopher Faulet67957bd2017-09-27 11:00:59 +020015202 Default value: 1s
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015203 <time> : time related to the event. It follows the HAProxy time format.
15204 <time> is expressed in milliseconds.
15205
Olivier Doucetaa1ea8a2016-08-05 17:15:20 +020015206 Example:
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015207
15208 resolvers mydns
15209 nameserver dns1 10.0.0.1:53
15210 nameserver dns2 10.0.0.2:53
Emeric Brunc8f3e452021-04-07 16:04:54 +020015211 nameserver dns3 tcp@10.0.0.3:53
Ben Draut44e609b2018-05-29 15:40:08 -060015212 parse-resolv-conf
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015213 resolve_retries 3
Christopher Faulet67957bd2017-09-27 11:00:59 +020015214 timeout resolve 1s
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015215 timeout retry 1s
Baptiste Assmann987e16d2016-11-02 22:23:31 +010015216 hold other 30s
15217 hold refused 30s
15218 hold nx 30s
15219 hold timeout 30s
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015220 hold valid 10s
Olivier Houcharda8c6db82017-07-06 18:46:47 +020015221 hold obsolete 30s
Baptiste Assmann1fa66662015-04-14 00:28:47 +020015222
15223
Christopher Faulet87f1f3d2019-07-18 14:51:20 +0200152246. Cache
15225---------
15226
15227HAProxy provides a cache, which was designed to perform cache on small objects
15228(favicon, css...). This is a minimalist low-maintenance cache which runs in
15229RAM.
15230
15231The cache is based on a memory which is shared between processes and threads,
15232this memory is split in blocks of 1k.
15233
15234If an object is not used anymore, it can be deleted to store a new object
15235independently of its expiration date. The oldest objects are deleted first
15236when we try to allocate a new one.
15237
15238The cache uses a hash of the host header and the URI as the key.
15239
15240It's possible to view the status of a cache using the Unix socket command
15241"show cache" consult section 9.3 "Unix Socket commands" of Management Guide
15242for more details.
15243
15244When an object is delivered from the cache, the server name in the log is
15245replaced by "<CACHE>".
15246
15247
152486.1. Limitation
15249----------------
15250
15251The cache won't store and won't deliver objects in these cases:
15252
15253- If the response is not a 200
Remi Tricot-Le Breton4f730832020-11-26 15:51:50 +010015254- If the response contains a Vary header and either the process-vary option is
15255 disabled, or a currently unmanaged header is specified in the Vary value (only
15256 accept-encoding and referer are managed for now)
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020015257- If the Content-Length + the headers size is greater than "max-object-size"
15258- If the response is not cacheable
Remi Tricot-Le Bretond493bc82020-11-26 15:51:29 +010015259- If the response does not have an explicit expiration time (s-maxage or max-age
15260 Cache-Control directives or Expires header) or a validator (ETag or Last-Modified
15261 headers)
Remi Tricot-Le Breton5853c0c2020-12-10 17:58:43 +010015262- If the process-vary option is enabled and there are already max-secondary-entries
15263 entries with the same primary key as the current response
Remi Tricot-Le Breton6ca89162021-01-07 14:50:51 +010015264- If the process-vary option is enabled and the response has an unknown encoding (not
15265 mentioned in https://www.iana.org/assignments/http-parameters/http-parameters.xhtml)
15266 while varying on the accept-encoding client header
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020015267
15268- If the request is not a GET
15269- If the HTTP version of the request is smaller than 1.1
15270- If the request contains an Authorization header
15271
15272
152736.2. Setup
15274-----------
15275
15276To setup a cache, you must define a cache section and use it in a proxy with
15277the corresponding http-request and response actions.
15278
15279
152806.2.1. Cache section
15281---------------------
15282
15283cache <name>
15284 Declare a cache section, allocate a shared cache memory named <name>, the
15285 size of cache is mandatory.
15286
15287total-max-size <megabytes>
15288 Define the size in RAM of the cache in megabytes. This size is split in
15289 blocks of 1kB which are used by the cache entries. Its maximum value is 4095.
15290
15291max-object-size <bytes>
15292 Define the maximum size of the objects to be cached. Must not be greater than
15293 an half of "total-max-size". If not set, it equals to a 256th of the cache size.
15294 All objects with sizes larger than "max-object-size" will not be cached.
15295
15296max-age <seconds>
Remi Tricot-Le Breton5853c0c2020-12-10 17:58:43 +010015297 Define the maximum expiration duration. The expiration is set as the lowest
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020015298 value between the s-maxage or max-age (in this order) directive in the
15299 Cache-Control response header and this value. The default value is 60
15300 seconds, which means that you can't cache an object more than 60 seconds by
15301 default.
15302
Remi Tricot-Le Bretone6cc5b52020-12-23 18:13:53 +010015303process-vary <on/off>
15304 Enable or disable the processing of the Vary header. When disabled, a response
Remi Tricot-Le Breton754b2422020-11-16 15:56:10 +010015305 containing such a header will never be cached. When enabled, we need to calculate
15306 a preliminary hash for a subset of request headers on all the incoming requests
15307 (which might come with a cpu cost) which will be used to build a secondary key
Remi Tricot-Le Bretone6cc5b52020-12-23 18:13:53 +010015308 for a given request (see RFC 7234#4.1). The default value is off (disabled).
Remi Tricot-Le Breton754b2422020-11-16 15:56:10 +010015309
Remi Tricot-Le Breton5853c0c2020-12-10 17:58:43 +010015310max-secondary-entries <number>
15311 Define the maximum number of simultaneous secondary entries with the same primary
15312 key in the cache. This needs the vary support to be enabled. Its default value is 10
15313 and should be passed a strictly positive integer.
15314
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020015315
153166.2.2. Proxy section
15317---------------------
15318
15319http-request cache-use <name> [ { if | unless } <condition> ]
15320 Try to deliver a cached object from the cache <name>. This directive is also
15321 mandatory to store the cache as it calculates the cache hash. If you want to
15322 use a condition for both storage and delivering that's a good idea to put it
15323 after this one.
15324
15325http-response cache-store <name> [ { if | unless } <condition> ]
15326 Store an http-response within the cache. The storage of the response headers
15327 is done at this step, which means you can use others http-response actions
15328 to modify headers before or after the storage of the response. This action
15329 is responsible for the setup of the cache storage filter.
15330
15331
15332Example:
15333
15334 backend bck1
15335 mode http
15336
15337 http-request cache-use foobar
15338 http-response cache-store foobar
15339 server srv1 127.0.0.1:80
15340
15341 cache foobar
15342 total-max-size 4
15343 max-age 240
15344
15345
Willy Tarreau74ca5042013-06-11 23:12:07 +0200153467. Using ACLs and fetching samples
15347----------------------------------
15348
Davor Ocelice9ed2812017-12-25 17:49:28 +010015349HAProxy is capable of extracting data from request or response streams, from
Willy Tarreau74ca5042013-06-11 23:12:07 +020015350client or server information, from tables, environmental information etc...
15351The action of extracting such data is called fetching a sample. Once retrieved,
15352these samples may be used for various purposes such as a key to a stick-table,
15353but most common usages consist in matching them against predefined constant
15354data called patterns.
15355
15356
153577.1. ACL basics
15358---------------
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015359
15360The use of Access Control Lists (ACL) provides a flexible solution to perform
15361content switching and generally to take decisions based on content extracted
15362from the request, the response or any environmental status. The principle is
15363simple :
15364
Willy Tarreau74ca5042013-06-11 23:12:07 +020015365 - extract a data sample from a stream, table or the environment
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015366 - optionally apply some format conversion to the extracted sample
Willy Tarreau74ca5042013-06-11 23:12:07 +020015367 - apply one or multiple pattern matching methods on this sample
15368 - perform actions only when a pattern matches the sample
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015369
Willy Tarreau74ca5042013-06-11 23:12:07 +020015370The actions generally consist in blocking a request, selecting a backend, or
15371adding a header.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015372
15373In order to define a test, the "acl" keyword is used. The syntax is :
15374
Willy Tarreau74ca5042013-06-11 23:12:07 +020015375 acl <aclname> <criterion> [flags] [operator] [<value>] ...
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015376
15377This creates a new ACL <aclname> or completes an existing one with new tests.
15378Those tests apply to the portion of request/response specified in <criterion>
15379and may be adjusted with optional flags [flags]. Some criteria also support
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015380an operator which may be specified before the set of values. Optionally some
15381conversion operators may be applied to the sample, and they will be specified
15382as a comma-delimited list of keywords just after the first keyword. The values
15383are of the type supported by the criterion, and are separated by spaces.
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015384
15385ACL names must be formed from upper and lower case letters, digits, '-' (dash),
15386'_' (underscore) , '.' (dot) and ':' (colon). ACL names are case-sensitive,
15387which means that "my_acl" and "My_Acl" are two different ACLs.
15388
15389There is no enforced limit to the number of ACLs. The unused ones do not affect
15390performance, they just consume a small amount of memory.
15391
Willy Tarreau74ca5042013-06-11 23:12:07 +020015392The criterion generally is the name of a sample fetch method, or one of its ACL
15393specific declinations. The default test method is implied by the output type of
15394this sample fetch method. The ACL declinations can describe alternate matching
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015395methods of a same sample fetch method. The sample fetch methods are the only
15396ones supporting a conversion.
Willy Tarreau74ca5042013-06-11 23:12:07 +020015397
15398Sample fetch methods return data which can be of the following types :
15399 - boolean
15400 - integer (signed or unsigned)
15401 - IPv4 or IPv6 address
15402 - string
15403 - data block
15404
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015405Converters transform any of these data into any of these. For example, some
15406converters might convert a string to a lower-case string while other ones
15407would turn a string to an IPv4 address, or apply a netmask to an IP address.
15408The resulting sample is of the type of the last converter applied to the list,
15409which defaults to the type of the sample fetch method.
15410
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015411Each sample or converter returns data of a specific type, specified with its
15412keyword in this documentation. When an ACL is declared using a standard sample
15413fetch method, certain types automatically involved a default matching method
15414which are summarized in the table below :
15415
15416 +---------------------+-----------------+
15417 | Sample or converter | Default |
15418 | output type | matching method |
15419 +---------------------+-----------------+
15420 | boolean | bool |
15421 +---------------------+-----------------+
15422 | integer | int |
15423 +---------------------+-----------------+
15424 | ip | ip |
15425 +---------------------+-----------------+
15426 | string | str |
15427 +---------------------+-----------------+
15428 | binary | none, use "-m" |
15429 +---------------------+-----------------+
15430
15431Note that in order to match a binary samples, it is mandatory to specify a
15432matching method, see below.
15433
Willy Tarreau74ca5042013-06-11 23:12:07 +020015434The ACL engine can match these types against patterns of the following types :
15435 - boolean
15436 - integer or integer range
15437 - IP address / network
15438 - string (exact, substring, suffix, prefix, subdir, domain)
15439 - regular expression
15440 - hex block
15441
Willy Tarreauc57f0e22009-05-10 13:12:33 +020015442The following ACL flags are currently supported :
15443
Willy Tarreau2b5285d2010-05-09 23:45:24 +020015444 -i : ignore case during matching of all subsequent patterns.
15445 -f : load patterns from a file.
Willy Tarreau74ca5042013-06-11 23:12:07 +020015446 -m : use a specific pattern matching method
Thierry FOURNIERb7729c92014-02-11 16:24:41 +010015447 -n : forbid the DNS resolutions
Thierry FOURNIER9860c412014-01-29 14:23:29 +010015448 -M : load the file pointed by -f like a map file.
Thierry FOURNIER3534d882014-01-20 17:01:44 +010015449 -u : force the unique id of the ACL
Willy Tarreau6a06a402007-07-15 20:15:28 +020015450 -- : force end of flags. Useful when a string looks like one of the flags.
15451
Willy Tarreau74ca5042013-06-11 23:12:07 +020015452The "-f" flag is followed by the name of a file from which all lines will be
15453read as individual values. It is even possible to pass multiple "-f" arguments
15454if the patterns are to be loaded from multiple files. Empty lines as well as
15455lines beginning with a sharp ('#') will be ignored. All leading spaces and tabs
15456will be stripped. If it is absolutely necessary to insert a valid pattern
15457beginning with a sharp, just prefix it with a space so that it is not taken for
Daniel Corbett9f0843f2021-05-08 10:50:37 -040015458a comment. Depending on the data type and match method, HAProxy may load the
Willy Tarreau74ca5042013-06-11 23:12:07 +020015459lines into a binary tree, allowing very fast lookups. This is true for IPv4 and
15460exact string matching. In this case, duplicates will automatically be removed.
15461
Thierry FOURNIER9860c412014-01-29 14:23:29 +010015462The "-M" flag allows an ACL to use a map file. If this flag is set, the file is
15463parsed as two column file. The first column contains the patterns used by the
15464ACL, and the second column contain the samples. The sample can be used later by
15465a map. This can be useful in some rare cases where an ACL would just be used to
15466check for the existence of a pattern in a map before a mapping is applied.
15467
Thierry FOURNIER3534d882014-01-20 17:01:44 +010015468The "-u" flag forces the unique id of the ACL. This unique id is used with the
15469socket interface to identify ACL and dynamically change its values. Note that a
15470file is always identified by its name even if an id is set.
15471
Willy Tarreau74ca5042013-06-11 23:12:07 +020015472Also, note that the "-i" flag applies to subsequent entries and not to entries
15473loaded from files preceding it. For instance :
15474
15475 acl valid-ua hdr(user-agent) -f exact-ua.lst -i -f generic-ua.lst test
15476
15477In this example, each line of "exact-ua.lst" will be exactly matched against
15478the "user-agent" header of the request. Then each line of "generic-ua" will be
15479case-insensitively matched. Then the word "test" will be insensitively matched
15480as well.
15481
15482The "-m" flag is used to select a specific pattern matching method on the input
15483sample. All ACL-specific criteria imply a pattern matching method and generally
15484do not need this flag. However, this flag is useful with generic sample fetch
15485methods to describe how they're going to be matched against the patterns. This
15486is required for sample fetches which return data type for which there is no
Davor Ocelice9ed2812017-12-25 17:49:28 +010015487obvious matching method (e.g. string or binary). When "-m" is specified and
Willy Tarreau74ca5042013-06-11 23:12:07 +020015488followed by a pattern matching method name, this method is used instead of the
15489default one for the criterion. This makes it possible to match contents in ways
15490that were not initially planned, or with sample fetch methods which return a
15491string. The matching method also affects the way the patterns are parsed.
15492
Thierry FOURNIERb7729c92014-02-11 16:24:41 +010015493The "-n" flag forbids the dns resolutions. It is used with the load of ip files.
15494By default, if the parser cannot parse ip address it considers that the parsed
15495string is maybe a domain name and try dns resolution. The flag "-n" disable this
15496resolution. It is useful for detecting malformed ip lists. Note that if the DNS
Daniel Corbett9f0843f2021-05-08 10:50:37 -040015497server is not reachable, the HAProxy configuration parsing may last many minutes
John Roeslerfb2fce12019-07-10 15:45:51 -050015498waiting for the timeout. During this time no error messages are displayed. The
Thierry FOURNIERb7729c92014-02-11 16:24:41 +010015499flag "-n" disable this behavior. Note also that during the runtime, this
15500function is disabled for the dynamic acl modifications.
15501
Willy Tarreau74ca5042013-06-11 23:12:07 +020015502There are some restrictions however. Not all methods can be used with all
15503sample fetch methods. Also, if "-m" is used in conjunction with "-f", it must
15504be placed first. The pattern matching method must be one of the following :
Willy Tarreau5adeda12013-03-31 22:13:34 +020015505
15506 - "found" : only check if the requested sample could be found in the stream,
15507 but do not compare it against any pattern. It is recommended not
Willy Tarreau74ca5042013-06-11 23:12:07 +020015508 to pass any pattern to avoid confusion. This matching method is
15509 particularly useful to detect presence of certain contents such
15510 as headers, cookies, etc... even if they are empty and without
15511 comparing them to anything nor counting them.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015512
15513 - "bool" : check the value as a boolean. It can only be applied to fetches
15514 which return a boolean or integer value, and takes no pattern.
Willy Tarreau74ca5042013-06-11 23:12:07 +020015515 Value zero or false does not match, all other values do match.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015516
15517 - "int" : match the value as an integer. It can be used with integer and
Willy Tarreau74ca5042013-06-11 23:12:07 +020015518 boolean samples. Boolean false is integer 0, true is integer 1.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015519
15520 - "ip" : match the value as an IPv4 or IPv6 address. It is compatible
Willy Tarreau74ca5042013-06-11 23:12:07 +020015521 with IP address samples only, so it is implied and never needed.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015522
Davor Ocelice9ed2812017-12-25 17:49:28 +010015523 - "bin" : match the contents against a hexadecimal string representing a
Willy Tarreau5adeda12013-03-31 22:13:34 +020015524 binary sequence. This may be used with binary or string samples.
15525
15526 - "len" : match the sample's length as an integer. This may be used with
15527 binary or string samples.
15528
Willy Tarreau74ca5042013-06-11 23:12:07 +020015529 - "str" : exact match : match the contents against a string. This may be
15530 used with binary or string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015531
Willy Tarreau74ca5042013-06-11 23:12:07 +020015532 - "sub" : substring match : check that the contents contain at least one of
15533 the provided string patterns. This may be used with binary or
15534 string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015535
Willy Tarreau74ca5042013-06-11 23:12:07 +020015536 - "reg" : regex match : match the contents against a list of regular
15537 expressions. This may be used with binary or string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015538
Willy Tarreau74ca5042013-06-11 23:12:07 +020015539 - "beg" : prefix match : check that the contents begin like the provided
15540 string patterns. This may be used with binary or string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015541
Willy Tarreau74ca5042013-06-11 23:12:07 +020015542 - "end" : suffix match : check that the contents end like the provided
15543 string patterns. This may be used with binary or string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015544
Willy Tarreau74ca5042013-06-11 23:12:07 +020015545 - "dir" : subdir match : check that a slash-delimited portion of the
15546 contents exactly matches one of the provided string patterns.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015547 This may be used with binary or string samples.
15548
Willy Tarreau74ca5042013-06-11 23:12:07 +020015549 - "dom" : domain match : check that a dot-delimited portion of the contents
15550 exactly match one of the provided string patterns. This may be
15551 used with binary or string samples.
Willy Tarreau5adeda12013-03-31 22:13:34 +020015552
15553For example, to quickly detect the presence of cookie "JSESSIONID" in an HTTP
15554request, it is possible to do :
15555
15556 acl jsess_present cook(JSESSIONID) -m found
15557
15558In order to apply a regular expression on the 500 first bytes of data in the
15559buffer, one would use the following acl :
15560
15561 acl script_tag payload(0,500) -m reg -i <script>
15562
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015563On systems where the regex library is much slower when using "-i", it is
15564possible to convert the sample to lowercase before matching, like this :
15565
15566 acl script_tag payload(0,500),lower -m reg <script>
15567
Willy Tarreau74ca5042013-06-11 23:12:07 +020015568All ACL-specific criteria imply a default matching method. Most often, these
15569criteria are composed by concatenating the name of the original sample fetch
15570method and the matching method. For example, "hdr_beg" applies the "beg" match
15571to samples retrieved using the "hdr" fetch method. Since all ACL-specific
15572criteria rely on a sample fetch method, it is always possible instead to use
15573the original sample fetch method and the explicit matching method using "-m".
Willy Tarreau2b5285d2010-05-09 23:45:24 +020015574
Willy Tarreau74ca5042013-06-11 23:12:07 +020015575If an alternate match is specified using "-m" on an ACL-specific criterion,
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030015576the matching method is simply applied to the underlying sample fetch method.
15577For example, all ACLs below are exact equivalent :
Willy Tarreau2b5285d2010-05-09 23:45:24 +020015578
Willy Tarreau74ca5042013-06-11 23:12:07 +020015579 acl short_form hdr_beg(host) www.
15580 acl alternate1 hdr_beg(host) -m beg www.
15581 acl alternate2 hdr_dom(host) -m beg www.
15582 acl alternate3 hdr(host) -m beg www.
Willy Tarreau2b5285d2010-05-09 23:45:24 +020015583
Willy Tarreau2b5285d2010-05-09 23:45:24 +020015584
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015585The table below summarizes the compatibility matrix between sample or converter
15586types and the pattern types to fetch against. It indicates for each compatible
15587combination the name of the matching method to be used, surrounded with angle
15588brackets ">" and "<" when the method is the default one and will work by
15589default without "-m".
Willy Tarreau0ba27502007-12-24 16:55:16 +010015590
Willy Tarreau74ca5042013-06-11 23:12:07 +020015591 +-------------------------------------------------+
15592 | Input sample type |
15593 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015594 | pattern type | boolean | integer | ip | string | binary |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015595 +----------------------+---------+---------+---------+---------+---------+
15596 | none (presence only) | found | found | found | found | found |
15597 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015598 | none (boolean value) |> bool <| bool | | bool | |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015599 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015600 | integer (value) | int |> int <| int | int | |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015601 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015602 | integer (length) | len | len | len | len | len |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015603 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015604 | IP address | | |> ip <| ip | ip |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015605 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIER2a06e392014-05-11 15:49:55 +020015606 | exact string | str | str | str |> str <| str |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015607 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015608 | prefix | beg | beg | beg | beg | beg |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015609 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015610 | suffix | end | end | end | end | end |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015611 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015612 | substring | sub | sub | sub | sub | sub |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015613 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015614 | subdir | dir | dir | dir | dir | dir |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015615 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015616 | domain | dom | dom | dom | dom | dom |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015617 +----------------------+---------+---------+---------+---------+---------+
Thierry FOURNIERe3ded592013-12-06 15:36:54 +010015618 | regex | reg | reg | reg | reg | reg |
Willy Tarreau74ca5042013-06-11 23:12:07 +020015619 +----------------------+---------+---------+---------+---------+---------+
15620 | hex block | | | | bin | bin |
15621 +----------------------+---------+---------+---------+---------+---------+
Willy Tarreau6a06a402007-07-15 20:15:28 +020015622
15623
Willy Tarreau74ca5042013-06-11 23:12:07 +0200156247.1.1. Matching booleans
15625------------------------
15626
15627In order to match a boolean, no value is needed and all values are ignored.
15628Boolean matching is used by default for all fetch methods of type "boolean".
15629When boolean matching is used, the fetched value is returned as-is, which means
15630that a boolean "true" will always match and a boolean "false" will never match.
15631
15632Boolean matching may also be enforced using "-m bool" on fetch methods which
15633return an integer value. Then, integer value 0 is converted to the boolean
15634"false" and all other values are converted to "true".
15635
Willy Tarreau6a06a402007-07-15 20:15:28 +020015636
Willy Tarreau74ca5042013-06-11 23:12:07 +0200156377.1.2. Matching integers
15638------------------------
15639
15640Integer matching applies by default to integer fetch methods. It can also be
15641enforced on boolean fetches using "-m int". In this case, "false" is converted
15642to the integer 0, and "true" is converted to the integer 1.
15643
15644Integer matching also supports integer ranges and operators. Note that integer
15645matching only applies to positive values. A range is a value expressed with a
15646lower and an upper bound separated with a colon, both of which may be omitted.
Willy Tarreau6a06a402007-07-15 20:15:28 +020015647
15648For instance, "1024:65535" is a valid range to represent a range of
15649unprivileged ports, and "1024:" would also work. "0:1023" is a valid
15650representation of privileged ports, and ":1023" would also work.
15651
Willy Tarreau62644772008-07-16 18:36:06 +020015652As a special case, some ACL functions support decimal numbers which are in fact
15653two integers separated by a dot. This is used with some version checks for
15654instance. All integer properties apply to those decimal numbers, including
15655ranges and operators.
15656
Willy Tarreau6a06a402007-07-15 20:15:28 +020015657For an easier usage, comparison operators are also supported. Note that using
Willy Tarreau0ba27502007-12-24 16:55:16 +010015658operators with ranges does not make much sense and is strongly discouraged.
15659Similarly, it does not make much sense to perform order comparisons with a set
15660of values.
Willy Tarreau6a06a402007-07-15 20:15:28 +020015661
Willy Tarreau0ba27502007-12-24 16:55:16 +010015662Available operators for integer matching are :
Willy Tarreau6a06a402007-07-15 20:15:28 +020015663
15664 eq : true if the tested value equals at least one value
15665 ge : true if the tested value is greater than or equal to at least one value
15666 gt : true if the tested value is greater than at least one value
15667 le : true if the tested value is less than or equal to at least one value
15668 lt : true if the tested value is less than at least one value
15669
Willy Tarreau0ba27502007-12-24 16:55:16 +010015670For instance, the following ACL matches any negative Content-Length header :
Willy Tarreau6a06a402007-07-15 20:15:28 +020015671
15672 acl negative-length hdr_val(content-length) lt 0
15673
Willy Tarreau62644772008-07-16 18:36:06 +020015674This one matches SSL versions between 3.0 and 3.1 (inclusive) :
15675
15676 acl sslv3 req_ssl_ver 3:3.1
15677
Willy Tarreau6a06a402007-07-15 20:15:28 +020015678
Willy Tarreau74ca5042013-06-11 23:12:07 +0200156797.1.3. Matching strings
15680-----------------------
15681
15682String matching applies to string or binary fetch methods, and exists in 6
15683different forms :
15684
15685 - exact match (-m str) : the extracted string must exactly match the
Davor Ocelice9ed2812017-12-25 17:49:28 +010015686 patterns;
Willy Tarreau74ca5042013-06-11 23:12:07 +020015687
15688 - substring match (-m sub) : the patterns are looked up inside the
Davor Ocelice9ed2812017-12-25 17:49:28 +010015689 extracted string, and the ACL matches if any of them is found inside;
Willy Tarreau74ca5042013-06-11 23:12:07 +020015690
15691 - prefix match (-m beg) : the patterns are compared with the beginning of
15692 the extracted string, and the ACL matches if any of them matches.
15693
15694 - suffix match (-m end) : the patterns are compared with the end of the
15695 extracted string, and the ACL matches if any of them matches.
15696
Baptiste Assmann33db6002016-03-06 23:32:10 +010015697 - subdir match (-m dir) : the patterns are looked up inside the extracted
Willy Tarreau74ca5042013-06-11 23:12:07 +020015698 string, delimited with slashes ("/"), and the ACL matches if any of them
15699 matches.
15700
15701 - domain match (-m dom) : the patterns are looked up inside the extracted
15702 string, delimited with dots ("."), and the ACL matches if any of them
15703 matches.
Willy Tarreau6a06a402007-07-15 20:15:28 +020015704
15705String matching applies to verbatim strings as they are passed, with the
15706exception of the backslash ("\") which makes it possible to escape some
15707characters such as the space. If the "-i" flag is passed before the first
15708string, then the matching will be performed ignoring the case. In order
15709to match the string "-i", either set it second, or pass the "--" flag
Willy Tarreau0ba27502007-12-24 16:55:16 +010015710before the first string. Same applies of course to match the string "--".
Willy Tarreau6a06a402007-07-15 20:15:28 +020015711
Mathias Weiersmuellercb250fc2019-12-02 09:43:40 +010015712Do not use string matches for binary fetches which might contain null bytes
15713(0x00), as the comparison stops at the occurrence of the first null byte.
15714Instead, convert the binary fetch to a hex string with the hex converter first.
15715
15716Example:
15717 # matches if the string <tag> is present in the binary sample
15718 acl tag_found req.payload(0,0),hex -m sub 3C7461673E
15719
Willy Tarreau6a06a402007-07-15 20:15:28 +020015720
Willy Tarreau74ca5042013-06-11 23:12:07 +0200157217.1.4. Matching regular expressions (regexes)
15722---------------------------------------------
Willy Tarreau6a06a402007-07-15 20:15:28 +020015723
15724Just like with string matching, regex matching applies to verbatim strings as
15725they are passed, with the exception of the backslash ("\") which makes it
15726possible to escape some characters such as the space. If the "-i" flag is
15727passed before the first regex, then the matching will be performed ignoring
15728the case. In order to match the string "-i", either set it second, or pass
Willy Tarreau0ba27502007-12-24 16:55:16 +010015729the "--" flag before the first string. Same principle applies of course to
15730match the string "--".
Willy Tarreau6a06a402007-07-15 20:15:28 +020015731
15732
Willy Tarreau74ca5042013-06-11 23:12:07 +0200157337.1.5. Matching arbitrary data blocks
15734-------------------------------------
15735
15736It is possible to match some extracted samples against a binary block which may
15737not safely be represented as a string. For this, the patterns must be passed as
15738a series of hexadecimal digits in an even number, when the match method is set
15739to binary. Each sequence of two digits will represent a byte. The hexadecimal
15740digits may be used upper or lower case.
15741
15742Example :
15743 # match "Hello\n" in the input stream (\x48 \x65 \x6c \x6c \x6f \x0a)
15744 acl hello payload(0,6) -m bin 48656c6c6f0a
15745
15746
157477.1.6. Matching IPv4 and IPv6 addresses
15748---------------------------------------
Willy Tarreau6a06a402007-07-15 20:15:28 +020015749
15750IPv4 addresses values can be specified either as plain addresses or with a
15751netmask appended, in which case the IPv4 address matches whenever it is
15752within the network. Plain addresses may also be replaced with a resolvable
Willy Tarreaud2a4aa22008-01-31 15:28:22 +010015753host name, but this practice is generally discouraged as it makes it more
Willy Tarreau0ba27502007-12-24 16:55:16 +010015754difficult to read and debug configurations. If hostnames are used, you should
15755at least ensure that they are present in /etc/hosts so that the configuration
15756does not depend on any random DNS match at the moment the configuration is
15757parsed.
Willy Tarreau6a06a402007-07-15 20:15:28 +020015758
Daniel Schnellereba56342016-04-13 00:26:52 +020015759The dotted IPv4 address notation is supported in both regular as well as the
15760abbreviated form with all-0-octets omitted:
15761
15762 +------------------+------------------+------------------+
15763 | Example 1 | Example 2 | Example 3 |
15764 +------------------+------------------+------------------+
15765 | 192.168.0.1 | 10.0.0.12 | 127.0.0.1 |
15766 | 192.168.1 | 10.12 | 127.1 |
15767 | 192.168.0.1/22 | 10.0.0.12/8 | 127.0.0.1/8 |
15768 | 192.168.1/22 | 10.12/8 | 127.1/8 |
15769 +------------------+------------------+------------------+
15770
15771Notice that this is different from RFC 4632 CIDR address notation in which
15772192.168.42/24 would be equivalent to 192.168.42.0/24.
15773
Willy Tarreauceb4ac92012-04-28 00:41:46 +020015774IPv6 may be entered in their usual form, with or without a netmask appended.
15775Only bit counts are accepted for IPv6 netmasks. In order to avoid any risk of
15776trouble with randomly resolved IP addresses, host names are never allowed in
15777IPv6 patterns.
15778
15779HAProxy is also able to match IPv4 addresses with IPv6 addresses in the
15780following situations :
15781 - tested address is IPv4, pattern address is IPv4, the match applies
15782 in IPv4 using the supplied mask if any.
15783 - tested address is IPv6, pattern address is IPv6, the match applies
15784 in IPv6 using the supplied mask if any.
15785 - tested address is IPv6, pattern address is IPv4, the match applies in IPv4
15786 using the pattern's mask if the IPv6 address matches with 2002:IPV4::,
15787 ::IPV4 or ::ffff:IPV4, otherwise it fails.
15788 - tested address is IPv4, pattern address is IPv6, the IPv4 address is first
15789 converted to IPv6 by prefixing ::ffff: in front of it, then the match is
15790 applied in IPv6 using the supplied IPv6 mask.
15791
Willy Tarreau74ca5042013-06-11 23:12:07 +020015792
157937.2. Using ACLs to form conditions
15794----------------------------------
15795
15796Some actions are only performed upon a valid condition. A condition is a
15797combination of ACLs with operators. 3 operators are supported :
15798
15799 - AND (implicit)
15800 - OR (explicit with the "or" keyword or the "||" operator)
15801 - Negation with the exclamation mark ("!")
Willy Tarreau6a06a402007-07-15 20:15:28 +020015802
Willy Tarreau74ca5042013-06-11 23:12:07 +020015803A condition is formed as a disjunctive form:
Willy Tarreau6a06a402007-07-15 20:15:28 +020015804
Willy Tarreau74ca5042013-06-11 23:12:07 +020015805 [!]acl1 [!]acl2 ... [!]acln { or [!]acl1 [!]acl2 ... [!]acln } ...
Willy Tarreaubef91e72013-03-31 23:14:46 +020015806
Willy Tarreau74ca5042013-06-11 23:12:07 +020015807Such conditions are generally used after an "if" or "unless" statement,
15808indicating when the condition will trigger the action.
Willy Tarreaubef91e72013-03-31 23:14:46 +020015809
Willy Tarreau74ca5042013-06-11 23:12:07 +020015810For instance, to block HTTP requests to the "*" URL with methods other than
15811"OPTIONS", as well as POST requests without content-length, and GET or HEAD
15812requests with a content-length greater than 0, and finally every request which
15813is not either GET/HEAD/POST/OPTIONS !
15814
15815 acl missing_cl hdr_cnt(Content-length) eq 0
Jarno Huuskonen84c51ec2017-04-03 14:20:34 +030015816 http-request deny if HTTP_URL_STAR !METH_OPTIONS || METH_POST missing_cl
15817 http-request deny if METH_GET HTTP_CONTENT
15818 http-request deny unless METH_GET or METH_POST or METH_OPTIONS
Willy Tarreau74ca5042013-06-11 23:12:07 +020015819
15820To select a different backend for requests to static contents on the "www" site
15821and to every request on the "img", "video", "download" and "ftp" hosts :
15822
15823 acl url_static path_beg /static /images /img /css
15824 acl url_static path_end .gif .png .jpg .css .js
15825 acl host_www hdr_beg(host) -i www
15826 acl host_static hdr_beg(host) -i img. video. download. ftp.
15827
Davor Ocelice9ed2812017-12-25 17:49:28 +010015828 # now use backend "static" for all static-only hosts, and for static URLs
Willy Tarreau74ca5042013-06-11 23:12:07 +020015829 # of host "www". Use backend "www" for the rest.
15830 use_backend static if host_static or host_www url_static
15831 use_backend www if host_www
15832
15833It is also possible to form rules using "anonymous ACLs". Those are unnamed ACL
15834expressions that are built on the fly without needing to be declared. They must
15835be enclosed between braces, with a space before and after each brace (because
15836the braces must be seen as independent words). Example :
15837
15838 The following rule :
15839
15840 acl missing_cl hdr_cnt(Content-length) eq 0
Jarno Huuskonen84c51ec2017-04-03 14:20:34 +030015841 http-request deny if METH_POST missing_cl
Willy Tarreau74ca5042013-06-11 23:12:07 +020015842
15843 Can also be written that way :
15844
Jarno Huuskonen84c51ec2017-04-03 14:20:34 +030015845 http-request deny if METH_POST { hdr_cnt(Content-length) eq 0 }
Willy Tarreau74ca5042013-06-11 23:12:07 +020015846
15847It is generally not recommended to use this construct because it's a lot easier
15848to leave errors in the configuration when written that way. However, for very
15849simple rules matching only one source IP address for instance, it can make more
15850sense to use them than to declare ACLs with random names. Another example of
15851good use is the following :
15852
15853 With named ACLs :
15854
15855 acl site_dead nbsrv(dynamic) lt 2
15856 acl site_dead nbsrv(static) lt 2
15857 monitor fail if site_dead
15858
15859 With anonymous ACLs :
15860
15861 monitor fail if { nbsrv(dynamic) lt 2 } || { nbsrv(static) lt 2 }
15862
Jarno Huuskonen84c51ec2017-04-03 14:20:34 +030015863See section 4.2 for detailed help on the "http-request deny" and "use_backend"
15864keywords.
Willy Tarreau74ca5042013-06-11 23:12:07 +020015865
15866
158677.3. Fetching samples
15868---------------------
15869
15870Historically, sample fetch methods were only used to retrieve data to match
15871against patterns using ACLs. With the arrival of stick-tables, a new class of
15872sample fetch methods was created, most often sharing the same syntax as their
15873ACL counterpart. These sample fetch methods are also known as "fetches". As
15874of now, ACLs and fetches have converged. All ACL fetch methods have been made
15875available as fetch methods, and ACLs may use any sample fetch method as well.
15876
15877This section details all available sample fetch methods and their output type.
15878Some sample fetch methods have deprecated aliases that are used to maintain
15879compatibility with existing configurations. They are then explicitly marked as
15880deprecated and should not be used in new setups.
15881
15882The ACL derivatives are also indicated when available, with their respective
15883matching methods. These ones all have a well defined default pattern matching
15884method, so it is never necessary (though allowed) to pass the "-m" option to
15885indicate how the sample will be matched using ACLs.
15886
15887As indicated in the sample type versus matching compatibility matrix above,
15888when using a generic sample fetch method in an ACL, the "-m" option is
15889mandatory unless the sample type is one of boolean, integer, IPv4 or IPv6. When
15890the same keyword exists as an ACL keyword and as a standard fetch method, the
15891ACL engine will automatically pick the ACL-only one by default.
15892
15893Some of these keywords support one or multiple mandatory arguments, and one or
15894multiple optional arguments. These arguments are strongly typed and are checked
15895when the configuration is parsed so that there is no risk of running with an
Davor Ocelice9ed2812017-12-25 17:49:28 +010015896incorrect argument (e.g. an unresolved backend name). Fetch function arguments
15897are passed between parenthesis and are delimited by commas. When an argument
Willy Tarreau74ca5042013-06-11 23:12:07 +020015898is optional, it will be indicated below between square brackets ('[ ]'). When
15899all arguments are optional, the parenthesis may be omitted.
15900
15901Thus, the syntax of a standard sample fetch method is one of the following :
15902 - name
15903 - name(arg1)
15904 - name(arg1,arg2)
15905
Thierry FOURNIER060762e2014-04-23 13:29:15 +020015906
159077.3.1. Converters
15908-----------------
15909
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015910Sample fetch methods may be combined with transformations to be applied on top
15911of the fetched sample (also called "converters"). These combinations form what
15912is called "sample expressions" and the result is a "sample". Initially this
15913was only supported by "stick on" and "stick store-request" directives but this
Davor Ocelice9ed2812017-12-25 17:49:28 +010015914has now be extended to all places where samples may be used (ACLs, log-format,
Willy Tarreaue6b11e42013-11-26 19:02:32 +010015915unique-id-format, add-header, ...).
15916
15917These transformations are enumerated as a series of specific keywords after the
15918sample fetch method. These keywords may equally be appended immediately after
15919the fetch keyword's argument, delimited by a comma. These keywords can also
Davor Ocelice9ed2812017-12-25 17:49:28 +010015920support some arguments (e.g. a netmask) which must be passed in parenthesis.
Willy Tarreau0ba27502007-12-24 16:55:16 +010015921
Willy Tarreau97707872015-01-27 15:12:13 +010015922A certain category of converters are bitwise and arithmetic operators which
15923support performing basic operations on integers. Some bitwise operations are
15924supported (and, or, xor, cpl) and some arithmetic operations are supported
15925(add, sub, mul, div, mod, neg). Some comparators are provided (odd, even, not,
15926bool) which make it possible to report a match without having to write an ACL.
15927
Willy Tarreau74ca5042013-06-11 23:12:07 +020015928The currently available list of transformation keywords include :
Willy Tarreau0ba27502007-12-24 16:55:16 +010015929
Ben Shillitof25e8e52016-12-02 14:25:37 +00001593051d.single(<prop>[,<prop>*])
15931 Returns values for the properties requested as a string, where values are
15932 separated by the delimiter specified with "51degrees-property-separator".
15933 The device is identified using the User-Agent header passed to the
15934 converter. The function can be passed up to five property names, and if a
15935 property name can't be found, the value "NoData" is returned.
15936
15937 Example :
Davor Ocelice9ed2812017-12-25 17:49:28 +010015938 # Here the header "X-51D-DeviceTypeMobileTablet" is added to the request,
15939 # containing values for the three properties requested by using the
Ben Shillitof25e8e52016-12-02 14:25:37 +000015940 # User-Agent passed to the converter.
15941 frontend http-in
15942 bind *:8081
15943 default_backend servers
15944 http-request set-header X-51D-DeviceTypeMobileTablet \
15945 %[req.fhdr(User-Agent),51d.single(DeviceType,IsMobile,IsTablet)]
15946
Willy Tarreau97707872015-01-27 15:12:13 +010015947add(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020015948 Adds <value> to the input value of type signed integer, and returns the
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020015949 result as a signed integer. <value> can be a numeric value or a variable
Daniel Schneller0b547052016-03-21 20:46:57 +010015950 name. The name of the variable starts with an indication about its scope. The
15951 scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010015952 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010015953 "sess" : the variable is shared with the whole session
15954 "txn" : the variable is shared with the transaction (request and response)
15955 "req" : the variable is shared only during request processing
15956 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010015957 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010015958 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010015959
Nenad Merdanovicc31499d2019-03-23 11:00:32 +010015960aes_gcm_dec(<bits>,<nonce>,<key>,<aead_tag>)
15961 Decrypts the raw byte input using the AES128-GCM, AES192-GCM or
15962 AES256-GCM algorithm, depending on the <bits> parameter. All other parameters
15963 need to be base64 encoded and the returned result is in raw byte format.
15964 If the <aead_tag> validation fails, the converter doesn't return any data.
15965 The <nonce>, <key> and <aead_tag> can either be strings or variables. This
15966 converter requires at least OpenSSL 1.0.1.
15967
15968 Example:
15969 http-response set-header X-Decrypted-Text %[var(txn.enc),\
15970 aes_gcm_dec(128,txn.nonce,Zm9vb2Zvb29mb29wZm9vbw==,txn.aead_tag)]
15971
Willy Tarreau97707872015-01-27 15:12:13 +010015972and(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020015973 Performs a bitwise "AND" between <value> and the input value of type signed
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020015974 integer, and returns the result as an signed integer. <value> can be a
Daniel Schneller0b547052016-03-21 20:46:57 +010015975 numeric value or a variable name. The name of the variable starts with an
15976 indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010015977 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010015978 "sess" : the variable is shared with the whole session
15979 "txn" : the variable is shared with the transaction (request and response)
15980 "req" : the variable is shared only during request processing
15981 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010015982 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010015983 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010015984
Holger Just1bfc24b2017-05-06 00:56:53 +020015985b64dec
15986 Converts (decodes) a base64 encoded input string to its binary
15987 representation. It performs the inverse operation of base64().
Moemen MHEDHBI92f7d432021-04-01 20:53:59 +020015988 For base64url("URL and Filename Safe Alphabet" (RFC 4648)) variant
15989 see "ub64dec".
Holger Just1bfc24b2017-05-06 00:56:53 +020015990
Emeric Brun53d1a982014-04-30 18:21:37 +020015991base64
15992 Converts a binary input sample to a base64 string. It is used to log or
Davor Ocelice9ed2812017-12-25 17:49:28 +010015993 transfer binary content in a way that can be reliably transferred (e.g.
Moemen MHEDHBI92f7d432021-04-01 20:53:59 +020015994 an SSL ID can be copied in a header). For base64url("URL and Filename
15995 Safe Alphabet" (RFC 4648)) variant see "ub64enc".
Emeric Brun53d1a982014-04-30 18:21:37 +020015996
Willy Tarreau97707872015-01-27 15:12:13 +010015997bool
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020015998 Returns a boolean TRUE if the input value of type signed integer is
Willy Tarreau97707872015-01-27 15:12:13 +010015999 non-null, otherwise returns FALSE. Used in conjunction with and(), it can be
Davor Ocelice9ed2812017-12-25 17:49:28 +010016000 used to report true/false for bit testing on input values (e.g. verify the
Willy Tarreau97707872015-01-27 15:12:13 +010016001 presence of a flag).
16002
Emeric Brun54c4ac82014-11-03 15:32:43 +010016003bytes(<offset>[,<length>])
16004 Extracts some bytes from an input binary sample. The result is a binary
16005 sample starting at an offset (in bytes) of the original sample and
Tim Düsterhus4896c442016-11-29 02:15:19 +010016006 optionally truncated at the given length.
Emeric Brun54c4ac82014-11-03 15:32:43 +010016007
Willy Tarreau280f42b2018-02-19 15:34:12 +010016008concat([<start>],[<var>],[<end>])
16009 Concatenates up to 3 fields after the current sample which is then turned to
16010 a string. The first one, <start>, is a constant string, that will be appended
16011 immediately after the existing sample. It may be omitted if not used. The
16012 second one, <var>, is a variable name. The variable will be looked up, its
16013 contents converted to a string, and it will be appended immediately after the
16014 <first> part. If the variable is not found, nothing is appended. It may be
16015 omitted as well. The third field, <end> is a constant string that will be
16016 appended after the variable. It may also be omitted. Together, these elements
16017 allow to concatenate variables with delimiters to an existing set of
16018 variables. This can be used to build new variables made of a succession of
Willy Tarreauef21fac2020-02-14 13:37:20 +010016019 other variables, such as colon-delimited values. If commas or closing
Daniel Corbett67a82712020-07-06 23:01:19 -040016020 parenthesis are needed as delimiters, they must be protected by quotes or
Willy Tarreauef21fac2020-02-14 13:37:20 +010016021 backslashes, themselves protected so that they are not stripped by the first
16022 level parser. See examples below.
Willy Tarreau280f42b2018-02-19 15:34:12 +010016023
16024 Example:
16025 tcp-request session set-var(sess.src) src
16026 tcp-request session set-var(sess.dn) ssl_c_s_dn
16027 tcp-request session set-var(txn.sig) str(),concat(<ip=,sess.ip,>),concat(<dn=,sess.dn,>)
Willy Tarreauef21fac2020-02-14 13:37:20 +010016028 tcp-request session set-var(txn.ipport) "str(),concat('addr=(',sess.ip),concat(',',sess.port,')')"
Willy Tarreau280f42b2018-02-19 15:34:12 +010016029 http-request set-header x-hap-sig %[var(txn.sig)]
16030
Willy Tarreau97707872015-01-27 15:12:13 +010016031cpl
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016032 Takes the input value of type signed integer, applies a ones-complement
16033 (flips all bits) and returns the result as an signed integer.
Willy Tarreau97707872015-01-27 15:12:13 +010016034
Willy Tarreau80599772015-01-20 19:35:24 +010016035crc32([<avalanche>])
16036 Hashes a binary input sample into an unsigned 32-bit quantity using the CRC32
16037 hash function. Optionally, it is possible to apply a full avalanche hash
16038 function to the output if the optional <avalanche> argument equals 1. This
16039 converter uses the same functions as used by the various hash-based load
16040 balancing algorithms, so it will provide exactly the same results. It is
16041 provided for compatibility with other software which want a CRC32 to be
16042 computed on some input keys, so it follows the most common implementation as
16043 found in Ethernet, Gzip, PNG, etc... It is slower than the other algorithms
16044 but may provide a better or at least less predictable distribution. It must
16045 not be used for security purposes as a 32-bit hash is trivial to break. See
Emmanuel Hocdet50791a72018-03-21 11:19:01 +010016046 also "djb2", "sdbm", "wt6", "crc32c" and the "hash-type" directive.
16047
16048crc32c([<avalanche>])
16049 Hashes a binary input sample into an unsigned 32-bit quantity using the CRC32C
16050 hash function. Optionally, it is possible to apply a full avalanche hash
16051 function to the output if the optional <avalanche> argument equals 1. This
16052 converter uses the same functions as described in RFC4960, Appendix B [8].
16053 It is provided for compatibility with other software which want a CRC32C to be
16054 computed on some input keys. It is slower than the other algorithms and it must
16055 not be used for security purposes as a 32-bit hash is trivial to break. See
16056 also "djb2", "sdbm", "wt6", "crc32" and the "hash-type" directive.
Willy Tarreau80599772015-01-20 19:35:24 +010016057
Christopher Fauletea159d62020-04-01 16:21:44 +020016058cut_crlf
16059 Cuts the string representation of the input sample on the first carriage
16060 return ('\r') or newline ('\n') character found. Only the string length is
16061 updated.
16062
David Carlier29b3ca32015-09-25 14:09:21 +010016063da-csv-conv(<prop>[,<prop>*])
David Carlier4542b102015-06-01 13:54:29 +020016064 Asks the DeviceAtlas converter to identify the User Agent string passed on
16065 input, and to emit a string made of the concatenation of the properties
16066 enumerated in argument, delimited by the separator defined by the global
16067 keyword "deviceatlas-property-separator", or by default the pipe character
Daniel Corbett9f0843f2021-05-08 10:50:37 -040016068 ('|'). There's a limit of 12 different properties imposed by the HAProxy
David Carlier4542b102015-06-01 13:54:29 +020016069 configuration language.
16070
16071 Example:
16072 frontend www
Cyril Bonté307ee1e2015-09-28 23:16:06 +020016073 bind *:8881
16074 default_backend servers
David Carlier840b0242016-03-16 10:09:55 +000016075 http-request set-header X-DeviceAtlas-Data %[req.fhdr(User-Agent),da-csv(primaryHardwareType,osName,osVersion,browserName,browserVersion,browserRenderingEngine)]
David Carlier4542b102015-06-01 13:54:29 +020016076
Willy Tarreau0851fd52019-12-17 10:07:25 +010016077debug([<prefix][,<destination>])
16078 This converter is used as debug tool. It takes a capture of the input sample
16079 and sends it to event sink <destination>, which may designate a ring buffer
16080 such as "buf0", as well as "stdout", or "stderr". Available sinks may be
16081 checked at run time by issuing "show events" on the CLI. When not specified,
16082 the output will be "buf0", which may be consulted via the CLI's "show events"
16083 command. An optional prefix <prefix> may be passed to help distinguish
16084 outputs from multiple expressions. It will then appear before the colon in
16085 the output message. The input sample is passed as-is on the output, so that
16086 it is safe to insert the debug converter anywhere in a chain, even with non-
16087 printable sample types.
16088
16089 Example:
16090 tcp-request connection track-sc0 src,debug(track-sc)
Thierry FOURNIER9687c772015-05-07 15:46:29 +020016091
Patrick Gansterer8e366512020-04-22 16:47:57 +020016092digest(<algorithm>)
16093 Converts a binary input sample to a message digest. The result is a binary
16094 sample. The <algorithm> must be an OpenSSL message digest name (e.g. sha256).
16095
Daniel Corbett9f0843f2021-05-08 10:50:37 -040016096 Please note that this converter is only available when HAProxy has been
Patrick Gansterer8e366512020-04-22 16:47:57 +020016097 compiled with USE_OPENSSL.
16098
Willy Tarreau97707872015-01-27 15:12:13 +010016099div(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016100 Divides the input value of type signed integer by <value>, and returns the
16101 result as an signed integer. If <value> is null, the largest unsigned
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016102 integer is returned (typically 2^63-1). <value> can be a numeric value or a
Daniel Schneller0b547052016-03-21 20:46:57 +010016103 variable name. The name of the variable starts with an indication about its
16104 scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016105 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016106 "sess" : the variable is shared with the whole session
16107 "txn" : the variable is shared with the transaction (request and response)
16108 "req" : the variable is shared only during request processing
16109 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010016110 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016111 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010016112
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020016113djb2([<avalanche>])
16114 Hashes a binary input sample into an unsigned 32-bit quantity using the DJB2
16115 hash function. Optionally, it is possible to apply a full avalanche hash
16116 function to the output if the optional <avalanche> argument equals 1. This
16117 converter uses the same functions as used by the various hash-based load
16118 balancing algorithms, so it will provide exactly the same results. It is
16119 mostly intended for debugging, but can be used as a stick-table entry to
16120 collect rough statistics. It must not be used for security purposes as a
Emmanuel Hocdet50791a72018-03-21 11:19:01 +010016121 32-bit hash is trivial to break. See also "crc32", "sdbm", "wt6", "crc32c",
16122 and the "hash-type" directive.
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020016123
Willy Tarreau97707872015-01-27 15:12:13 +010016124even
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016125 Returns a boolean TRUE if the input value of type signed integer is even
Willy Tarreau97707872015-01-27 15:12:13 +010016126 otherwise returns FALSE. It is functionally equivalent to "not,and(1),bool".
16127
Marcin Deranek9631a282018-04-16 14:30:46 +020016128field(<index>,<delimiters>[,<count>])
16129 Extracts the substring at the given index counting from the beginning
16130 (positive index) or from the end (negative index) considering given delimiters
16131 from an input string. Indexes start at 1 or -1 and delimiters are a string
16132 formatted list of chars. Optionally you can specify <count> of fields to
16133 extract (default: 1). Value of 0 indicates extraction of all remaining
16134 fields.
16135
16136 Example :
16137 str(f1_f2_f3__f5),field(5,_) # f5
16138 str(f1_f2_f3__f5),field(2,_,0) # f2_f3__f5
16139 str(f1_f2_f3__f5),field(2,_,2) # f2_f3
16140 str(f1_f2_f3__f5),field(-2,_,3) # f2_f3_
16141 str(f1_f2_f3__f5),field(-3,_,0) # f1_f2_f3
Emeric Brunf399b0d2014-11-03 17:07:03 +010016142
Baptiste Assmanne138dda2020-10-22 15:39:03 +020016143fix_is_valid
16144 Parses a binary payload and performs sanity checks regarding FIX (Financial
16145 Information eXchange):
16146
16147 - checks that all tag IDs and values are not empty and the tags IDs are well
16148 numeric
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +050016149 - checks the BeginString tag is the first tag with a valid FIX version
Baptiste Assmanne138dda2020-10-22 15:39:03 +020016150 - checks the BodyLength tag is the second one with the right body length
Christopher Fauleted4bef72021-03-18 17:40:56 +010016151 - checks the MsgType tag is the third tag.
Baptiste Assmanne138dda2020-10-22 15:39:03 +020016152 - checks that last tag in the message is the CheckSum tag with a valid
16153 checksum
16154
16155 Due to current HAProxy design, only the first message sent by the client and
16156 the server can be parsed.
16157
16158 This converter returns a boolean, true if the payload contains a valid FIX
16159 message, false if not.
16160
16161 See also the fix_tag_value converter.
16162
16163 Example:
16164 tcp-request inspect-delay 10s
16165 tcp-request content reject unless { req.payload(0,0),fix_is_valid }
16166
16167fix_tag_value(<tag>)
16168 Parses a FIX (Financial Information eXchange) message and extracts the value
16169 from the tag <tag>. <tag> can be a string or an integer pointing to the
16170 desired tag. Any integer value is accepted, but only the following strings
16171 are translated into their integer equivalent: BeginString, BodyLength,
Daniel Corbettbefef702021-03-09 23:00:34 -050016172 MsgType, SenderCompID, TargetCompID, CheckSum. More tag names can be easily
Baptiste Assmanne138dda2020-10-22 15:39:03 +020016173 added.
16174
16175 Due to current HAProxy design, only the first message sent by the client and
16176 the server can be parsed. No message validation is performed by this
16177 converter. It is highly recommended to validate the message first using
16178 fix_is_valid converter.
16179
16180 See also the fix_is_valid converter.
16181
16182 Example:
16183 tcp-request inspect-delay 10s
16184 tcp-request content reject unless { req.payload(0,0),fix_is_valid }
16185 # MsgType tag ID is 35, so both lines below will return the same content
16186 tcp-request content set-var(txn.foo) req.payload(0,0),fix_tag_value(35)
16187 tcp-request content set-var(txn.bar) req.payload(0,0),fix_tag_value(MsgType)
16188
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016189hex
Davor Ocelice9ed2812017-12-25 17:49:28 +010016190 Converts a binary input sample to a hex string containing two hex digits per
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016191 input byte. It is used to log or transfer hex dumps of some binary input data
Davor Ocelice9ed2812017-12-25 17:49:28 +010016192 in a way that can be reliably transferred (e.g. an SSL ID can be copied in a
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016193 header).
Thierry FOURNIER2f49d6d2014-03-12 15:01:52 +010016194
Dragan Dosen3f957b22017-10-24 09:27:34 +020016195hex2i
16196 Converts a hex string containing two hex digits per input byte to an
John Roeslerfb2fce12019-07-10 15:45:51 -050016197 integer. If the input value cannot be converted, then zero is returned.
Dragan Dosen3f957b22017-10-24 09:27:34 +020016198
Christopher Faulet4ccc12f2020-04-01 09:08:32 +020016199htonl
16200 Converts the input integer value to its 32-bit binary representation in the
16201 network byte order. Because sample fetches own signed 64-bit integer, when
16202 this converter is used, the input integer value is first casted to an
16203 unsigned 32-bit integer.
16204
Tim Duesterhusa3082092021-01-21 17:40:49 +010016205hmac(<algorithm>,<key>)
Patrick Gansterer8e366512020-04-22 16:47:57 +020016206 Converts a binary input sample to a message authentication code with the given
16207 key. The result is a binary sample. The <algorithm> must be one of the
16208 registered OpenSSL message digest names (e.g. sha256). The <key> parameter must
16209 be base64 encoded and can either be a string or a variable.
16210
Daniel Corbett9f0843f2021-05-08 10:50:37 -040016211 Please note that this converter is only available when HAProxy has been
Patrick Gansterer8e366512020-04-22 16:47:57 +020016212 compiled with USE_OPENSSL.
16213
Cyril Bonté6bcd1822019-11-05 23:13:59 +010016214http_date([<offset],[<unit>])
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016215 Converts an integer supposed to contain a date since epoch to a string
16216 representing this date in a format suitable for use in HTTP header fields. If
Damien Claisseae6f1252019-10-30 15:57:28 +000016217 an offset value is specified, then it is added to the date before the
16218 conversion is operated. This is particularly useful to emit Date header fields,
16219 Expires values in responses when combined with a positive offset, or
16220 Last-Modified values when the offset is negative.
16221 If a unit value is specified, then consider the timestamp as either
16222 "s" for seconds (default behavior), "ms" for milliseconds, or "us" for
16223 microseconds since epoch. Offset is assumed to have the same unit as
16224 input timestamp.
Willy Tarreau74ca5042013-06-11 23:12:07 +020016225
Tim Duesterhus3943e4f2020-09-11 14:25:23 +020016226iif(<true>,<false>)
16227 Returns the <true> string if the input value is true. Returns the <false>
16228 string otherwise.
16229
16230 Example:
Tim Duesterhus870713b2020-09-11 17:13:12 +020016231 http-request set-header x-forwarded-proto %[ssl_fc,iif(https,http)]
Tim Duesterhus3943e4f2020-09-11 14:25:23 +020016232
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016233in_table(<table>)
16234 Uses the string representation of the input sample to perform a look up in
16235 the specified table. If the key is not found in the table, a boolean false
16236 is returned. Otherwise a boolean true is returned. This can be used to verify
Davor Ocelice9ed2812017-12-25 17:49:28 +010016237 the presence of a certain key in a table tracking some elements (e.g. whether
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016238 or not a source IP address or an Authorization header was already seen).
16239
Tim Duesterhusa3082092021-01-21 17:40:49 +010016240ipmask(<mask4>,[<mask6>])
Tim Duesterhus1478aa72018-01-25 16:24:51 +010016241 Apply a mask to an IP address, and use the result for lookups and storage.
Willy Tarreauffcb2e42014-07-10 16:29:08 +020016242 This can be used to make all hosts within a certain mask to share the same
Tim Duesterhus1478aa72018-01-25 16:24:51 +010016243 table entries and as such use the same server. The mask4 can be passed in
16244 dotted form (e.g. 255.255.255.0) or in CIDR form (e.g. 24). The mask6 can
16245 be passed in quadruplet form (e.g. ffff:ffff::) or in CIDR form (e.g. 64).
16246 If no mask6 is given IPv6 addresses will fail to convert for backwards
16247 compatibility reasons.
Willy Tarreauffcb2e42014-07-10 16:29:08 +020016248
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016249json([<input-code>])
Davor Ocelice9ed2812017-12-25 17:49:28 +010016250 Escapes the input string and produces an ASCII output string ready to use as a
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016251 JSON string. The converter tries to decode the input string according to the
Herve COMMOWICK8dfe8632016-08-05 12:01:20 +020016252 <input-code> parameter. It can be "ascii", "utf8", "utf8s", "utf8p" or
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016253 "utf8ps". The "ascii" decoder never fails. The "utf8" decoder detects 3 types
16254 of errors:
16255 - bad UTF-8 sequence (lone continuation byte, bad number of continuation
16256 bytes, ...)
16257 - invalid range (the decoded value is within a UTF-8 prohibited range),
16258 - code overlong (the value is encoded with more bytes than necessary).
16259
16260 The UTF-8 JSON encoding can produce a "too long value" error when the UTF-8
16261 character is greater than 0xffff because the JSON string escape specification
16262 only authorizes 4 hex digits for the value encoding. The UTF-8 decoder exists
16263 in 4 variants designated by a combination of two suffix letters : "p" for
16264 "permissive" and "s" for "silently ignore". The behaviors of the decoders
16265 are :
Davor Ocelice9ed2812017-12-25 17:49:28 +010016266 - "ascii" : never fails;
16267 - "utf8" : fails on any detected errors;
16268 - "utf8s" : never fails, but removes characters corresponding to errors;
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016269 - "utf8p" : accepts and fixes the overlong errors, but fails on any other
Davor Ocelice9ed2812017-12-25 17:49:28 +010016270 error;
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016271 - "utf8ps" : never fails, accepts and fixes the overlong errors, but removes
16272 characters corresponding to the other errors.
16273
16274 This converter is particularly useful for building properly escaped JSON for
Davor Ocelice9ed2812017-12-25 17:49:28 +010016275 logging to servers which consume JSON-formatted traffic logs.
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016276
16277 Example:
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016278 capture request header Host len 15
Herve COMMOWICK8dfe8632016-08-05 12:01:20 +020016279 capture request header user-agent len 150
16280 log-format '{"ip":"%[src]","user-agent":"%[capture.req.hdr(1),json(utf8s)]"}'
Thierry FOURNIER317e1c42014-08-12 10:20:47 +020016281
16282 Input request from client 127.0.0.1:
16283 GET / HTTP/1.0
16284 User-Agent: Very "Ugly" UA 1/2
16285
16286 Output log:
16287 {"ip":"127.0.0.1","user-agent":"Very \"Ugly\" UA 1\/2"}
16288
Alex51c8ad42021-04-15 16:45:15 +020016289json_query(<json_path>,[<output_type>])
16290 The json_query converter supports the JSON types string, boolean and
16291 number. Floating point numbers will be returned as a string. By
16292 specifying the output_type 'int' the value will be converted to an
16293 Integer. If conversion is not possible the json_query converter fails.
16294
16295 <json_path> must be a valid JSON Path string as defined in
16296 https://datatracker.ietf.org/doc/draft-ietf-jsonpath-base/
16297
16298 Example:
16299 # get a integer value from the request body
16300 # "{"integer":4}" => 5
16301 http-request set-var(txn.pay_int) req.body,json_query('$.integer','int'),add(1)
16302
16303 # get a key with '.' in the name
16304 # {"my.key":"myvalue"} => myvalue
16305 http-request set-var(txn.pay_mykey) req.body,json_query('$.my\\.key')
16306
16307 # {"boolean-false":false} => 0
16308 http-request set-var(txn.pay_boolean_false) req.body,json_query('$.boolean-false')
16309
16310 # get the value of the key 'iss' from a JWT Bearer token
16311 http-request set-var(txn.token_payload) req.hdr(Authorization),word(2,.),ub64dec,json_query('$.iss')
16312
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016313language(<value>[,<default>])
16314 Returns the value with the highest q-factor from a list as extracted from the
16315 "accept-language" header using "req.fhdr". Values with no q-factor have a
16316 q-factor of 1. Values with a q-factor of 0 are dropped. Only values which
16317 belong to the list of semi-colon delimited <values> will be considered. The
16318 argument <value> syntax is "lang[;lang[;lang[;...]]]". If no value matches the
16319 given list and a default value is provided, it is returned. Note that language
16320 names may have a variant after a dash ('-'). If this variant is present in the
16321 list, it will be matched, but if it is not, only the base language is checked.
16322 The match is case-sensitive, and the output string is always one of those
Davor Ocelice9ed2812017-12-25 17:49:28 +010016323 provided in arguments. The ordering of arguments is meaningless, only the
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016324 ordering of the values in the request counts, as the first value among
16325 multiple sharing the same q-factor is used.
Thierry FOURNIERad903512014-04-11 17:51:01 +020016326
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016327 Example :
Thierry FOURNIERad903512014-04-11 17:51:01 +020016328
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016329 # this configuration switches to the backend matching a
16330 # given language based on the request :
Thierry FOURNIERad903512014-04-11 17:51:01 +020016331
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016332 acl es req.fhdr(accept-language),language(es;fr;en) -m str es
16333 acl fr req.fhdr(accept-language),language(es;fr;en) -m str fr
16334 acl en req.fhdr(accept-language),language(es;fr;en) -m str en
16335 use_backend spanish if es
16336 use_backend french if fr
16337 use_backend english if en
16338 default_backend choose_your_language
Thierry FOURNIERad903512014-04-11 17:51:01 +020016339
Willy Tarreau60a2ee72017-12-15 07:13:48 +010016340length
Etienne Carriereed0d24e2017-12-13 13:41:34 +010016341 Get the length of the string. This can only be placed after a string
16342 sample fetch function or after a transformation keyword returning a string
16343 type. The result is of type integer.
16344
Willy Tarreauffcb2e42014-07-10 16:29:08 +020016345lower
16346 Convert a string sample to lower case. This can only be placed after a string
16347 sample fetch function or after a transformation keyword returning a string
16348 type. The result is of type string.
16349
Willy Tarreau0dbfdba2014-07-10 16:37:47 +020016350ltime(<format>[,<offset>])
16351 Converts an integer supposed to contain a date since epoch to a string
16352 representing this date in local time using a format defined by the <format>
16353 string using strftime(3). The purpose is to allow any date format to be used
16354 in logs. An optional <offset> in seconds may be applied to the input date
16355 (positive or negative). See the strftime() man page for the format supported
16356 by your operating system. See also the utime converter.
16357
16358 Example :
16359
16360 # Emit two colons, one with the local time and another with ip:port
Davor Ocelice9ed2812017-12-25 17:49:28 +010016361 # e.g. 20140710162350 127.0.0.1:57325
Willy Tarreau0dbfdba2014-07-10 16:37:47 +020016362 log-format %[date,ltime(%Y%m%d%H%M%S)]\ %ci:%cp
16363
Christopher Faulet51fc9d12020-04-01 17:24:41 +020016364ltrim(<chars>)
16365 Skips any characters from <chars> from the beginning of the string
16366 representation of the input sample.
16367
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016368map(<map_file>[,<default_value>])
16369map_<match_type>(<map_file>[,<default_value>])
16370map_<match_type>_<output_type>(<map_file>[,<default_value>])
16371 Search the input value from <map_file> using the <match_type> matching method,
16372 and return the associated value converted to the type <output_type>. If the
16373 input value cannot be found in the <map_file>, the converter returns the
16374 <default_value>. If the <default_value> is not set, the converter fails and
16375 acts as if no input value could be fetched. If the <match_type> is not set, it
16376 defaults to "str". Likewise, if the <output_type> is not set, it defaults to
16377 "str". For convenience, the "map" keyword is an alias for "map_str" and maps a
16378 string to another string.
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010016379
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016380 It is important to avoid overlapping between the keys : IP addresses and
16381 strings are stored in trees, so the first of the finest match will be used.
16382 Other keys are stored in lists, so the first matching occurrence will be used.
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010016383
Tim Düsterhus4896c442016-11-29 02:15:19 +010016384 The following array contains the list of all map functions available sorted by
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016385 input type, match type and output type.
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010016386
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016387 input type | match method | output type str | output type int | output type ip
16388 -----------+--------------+-----------------+-----------------+---------------
16389 str | str | map_str | map_str_int | map_str_ip
16390 -----------+--------------+-----------------+-----------------+---------------
Willy Tarreau787a4c02014-05-10 07:55:30 +020016391 str | beg | map_beg | map_beg_int | map_end_ip
16392 -----------+--------------+-----------------+-----------------+---------------
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016393 str | sub | map_sub | map_sub_int | map_sub_ip
16394 -----------+--------------+-----------------+-----------------+---------------
16395 str | dir | map_dir | map_dir_int | map_dir_ip
16396 -----------+--------------+-----------------+-----------------+---------------
16397 str | dom | map_dom | map_dom_int | map_dom_ip
16398 -----------+--------------+-----------------+-----------------+---------------
16399 str | end | map_end | map_end_int | map_end_ip
16400 -----------+--------------+-----------------+-----------------+---------------
Ruoshan Huang3c5e3742016-12-02 16:25:31 +080016401 str | reg | map_reg | map_reg_int | map_reg_ip
16402 -----------+--------------+-----------------+-----------------+---------------
16403 str | reg | map_regm | map_reg_int | map_reg_ip
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016404 -----------+--------------+-----------------+-----------------+---------------
16405 int | int | map_int | map_int_int | map_int_ip
16406 -----------+--------------+-----------------+-----------------+---------------
16407 ip | ip | map_ip | map_ip_int | map_ip_ip
16408 -----------+--------------+-----------------+-----------------+---------------
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010016409
Thierry Fournier8feaa662016-02-10 22:55:20 +010016410 The special map called "map_regm" expect matching zone in the regular
16411 expression and modify the output replacing back reference (like "\1") by
16412 the corresponding match text.
16413
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016414 The file contains one key + value per line. Lines which start with '#' are
16415 ignored, just like empty lines. Leading tabs and spaces are stripped. The key
16416 is then the first "word" (series of non-space/tabs characters), and the value
16417 is what follows this series of space/tab till the end of the line excluding
16418 trailing spaces/tabs.
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010016419
Thierry FOURNIER060762e2014-04-23 13:29:15 +020016420 Example :
16421
16422 # this is a comment and is ignored
16423 2.22.246.0/23 United Kingdom \n
16424 <-><-----------><--><------------><---->
16425 | | | | `- trailing spaces ignored
16426 | | | `---------- value
16427 | | `-------------------- middle spaces ignored
16428 | `---------------------------- key
16429 `------------------------------------ leading spaces ignored
16430
Willy Tarreau97707872015-01-27 15:12:13 +010016431mod(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016432 Divides the input value of type signed integer by <value>, and returns the
16433 remainder as an signed integer. If <value> is null, then zero is returned.
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016434 <value> can be a numeric value or a variable name. The name of the variable
Daniel Schneller0b547052016-03-21 20:46:57 +010016435 starts with an indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016436 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016437 "sess" : the variable is shared with the whole session
16438 "txn" : the variable is shared with the transaction (request and response)
16439 "req" : the variable is shared only during request processing
16440 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010016441 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016442 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010016443
Alexbf1bd5a2021-04-24 13:02:21 +020016444mqtt_field_value(<packettype>,<fieldname_or_property_ID>)
Baptiste Assmanne279ca62020-10-27 18:10:06 +010016445 Returns value of <fieldname> found in input MQTT payload of type
16446 <packettype>.
16447 <packettype> can be either a string (case insensitive matching) or a numeric
16448 value corresponding to the type of packet we're supposed to extract data
16449 from.
16450 Supported string and integers can be found here:
16451 https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html#_Toc398718021
16452 https://docs.oasis-open.org/mqtt/mqtt/v5.0/os/mqtt-v5.0-os.html#_Toc3901022
16453
16454 <fieldname> depends on <packettype> and can be any of the following below.
16455 (note that <fieldname> matching is case insensitive).
16456 <property id> can only be found in MQTT v5.0 streams. check this table:
16457 https://docs.oasis-open.org/mqtt/mqtt/v5.0/os/mqtt-v5.0-os.html#_Toc3901029
16458
16459 - CONNECT (or 1): flags, protocol_name, protocol_version, client_identifier,
16460 will_topic, will_payload, username, password, keepalive
16461 OR any property ID as a numeric value (for MQTT v5.0
16462 packets only):
16463 17: Session Expiry Interval
16464 33: Receive Maximum
16465 39: Maximum Packet Size
16466 34: Topic Alias Maximum
16467 25: Request Response Information
16468 23: Request Problem Information
16469 21: Authentication Method
16470 22: Authentication Data
16471 18: Will Delay Interval
16472 1: Payload Format Indicator
16473 2: Message Expiry Interval
16474 3: Content Type
16475 8: Response Topic
16476 9: Correlation Data
16477 Not supported yet:
16478 38: User Property
16479
16480 - CONNACK (or 2): flags, protocol_version, reason_code
16481 OR any property ID as a numeric value (for MQTT v5.0
16482 packets only):
16483 17: Session Expiry Interval
16484 33: Receive Maximum
16485 36: Maximum QoS
16486 37: Retain Available
16487 39: Maximum Packet Size
16488 18: Assigned Client Identifier
16489 34: Topic Alias Maximum
16490 31: Reason String
16491 40; Wildcard Subscription Available
16492 41: Subscription Identifiers Available
16493 42: Shared Subscription Available
16494 19: Server Keep Alive
16495 26: Response Information
16496 28: Server Reference
16497 21: Authentication Method
16498 22: Authentication Data
16499 Not supported yet:
16500 38: User Property
16501
16502 Due to current HAProxy design, only the first message sent by the client and
16503 the server can be parsed. Thus this converter can extract data only from
16504 CONNECT and CONNACK packet types. CONNECT is the first message sent by the
16505 client and CONNACK is the first response sent by the server.
16506
16507 Example:
16508
16509 acl data_in_buffer req.len ge 4
16510 tcp-request content set-var(txn.username) \
16511 req.payload(0,0),mqtt_field_value(connect,protocol_name) \
16512 if data_in_buffer
16513 # do the same as above
16514 tcp-request content set-var(txn.username) \
16515 req.payload(0,0),mqtt_field_value(1,protocol_name) \
16516 if data_in_buffer
16517
16518mqtt_is_valid
16519 Checks that the binary input is a valid MQTT packet. It returns a boolean.
16520
16521 Due to current HAProxy design, only the first message sent by the client and
16522 the server can be parsed. Thus this converter can extract data only from
16523 CONNECT and CONNACK packet types. CONNECT is the first message sent by the
16524 client and CONNACK is the first response sent by the server.
16525
16526 Example:
16527
16528 acl data_in_buffer req.len ge 4
Daniel Corbettcc9d9b02021-05-13 10:46:07 -040016529 tcp-request content reject unless { req.payload(0,0),mqtt_is_valid }
Baptiste Assmanne279ca62020-10-27 18:10:06 +010016530
Willy Tarreau97707872015-01-27 15:12:13 +010016531mul(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016532 Multiplies the input value of type signed integer by <value>, and returns
Thierry FOURNIER00c005c2015-07-08 01:10:21 +020016533 the product as an signed integer. In case of overflow, the largest possible
16534 value for the sign is returned so that the operation doesn't wrap around.
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016535 <value> can be a numeric value or a variable name. The name of the variable
Daniel Schneller0b547052016-03-21 20:46:57 +010016536 starts with an indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016537 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016538 "sess" : the variable is shared with the whole session
16539 "txn" : the variable is shared with the transaction (request and response)
16540 "req" : the variable is shared only during request processing
16541 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010016542 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016543 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010016544
Nenad Merdanovicb7e7c472017-03-12 21:56:55 +010016545nbsrv
16546 Takes an input value of type string, interprets it as a backend name and
16547 returns the number of usable servers in that backend. Can be used in places
16548 where we want to look up a backend from a dynamic name, like a result of a
16549 map lookup.
16550
Willy Tarreau97707872015-01-27 15:12:13 +010016551neg
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016552 Takes the input value of type signed integer, computes the opposite value,
16553 and returns the remainder as an signed integer. 0 is identity. This operator
16554 is provided for reversed subtracts : in order to subtract the input from a
16555 constant, simply perform a "neg,add(value)".
Willy Tarreau97707872015-01-27 15:12:13 +010016556
16557not
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016558 Returns a boolean FALSE if the input value of type signed integer is
Willy Tarreau97707872015-01-27 15:12:13 +010016559 non-null, otherwise returns TRUE. Used in conjunction with and(), it can be
Davor Ocelice9ed2812017-12-25 17:49:28 +010016560 used to report true/false for bit testing on input values (e.g. verify the
Willy Tarreau97707872015-01-27 15:12:13 +010016561 absence of a flag).
16562
16563odd
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016564 Returns a boolean TRUE if the input value of type signed integer is odd
Willy Tarreau97707872015-01-27 15:12:13 +010016565 otherwise returns FALSE. It is functionally equivalent to "and(1),bool".
16566
16567or(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016568 Performs a bitwise "OR" between <value> and the input value of type signed
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016569 integer, and returns the result as an signed integer. <value> can be a
Daniel Schneller0b547052016-03-21 20:46:57 +010016570 numeric value or a variable name. The name of the variable starts with an
16571 indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016572 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016573 "sess" : the variable is shared with the whole session
16574 "txn" : the variable is shared with the transaction (request and response)
16575 "req" : the variable is shared only during request processing
16576 "res" : the variable is shared only during response processing
Davor Ocelice9ed2812017-12-25 17:49:28 +010016577 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016578 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010016579
Frédéric Lécaillebfe61382019-03-06 14:34:36 +010016580protobuf(<field_number>,[<field_type>])
16581 This extracts the protocol buffers message field in raw mode of an input binary
16582 sample representation of a protocol buffer message with <field_number> as field
16583 number (dotted notation) if <field_type> is not present, or as an integer sample
16584 if this field is present (see also "ungrpc" below).
16585 The list of the authorized types is the following one: "int32", "int64", "uint32",
16586 "uint64", "sint32", "sint64", "bool", "enum" for the "varint" wire type 0
16587 "fixed64", "sfixed64", "double" for the 64bit wire type 1, "fixed32", "sfixed32",
16588 "float" for the wire type 5. Note that "string" is considered as a length-delimited
16589 type, so it does not require any <field_type> argument to be extracted.
16590 More information may be found here about the protocol buffers message field types:
16591 https://developers.google.com/protocol-buffers/docs/encoding
16592
Willy Tarreauc4dc3502015-01-23 20:39:28 +010016593regsub(<regex>,<subst>[,<flags>])
Willy Tarreau7eda8492015-01-20 19:47:06 +010016594 Applies a regex-based substitution to the input string. It does the same
16595 operation as the well-known "sed" utility with "s/<regex>/<subst>/". By
16596 default it will replace in the input string the first occurrence of the
16597 largest part matching the regular expression <regex> with the substitution
16598 string <subst>. It is possible to replace all occurrences instead by adding
16599 the flag "g" in the third argument <flags>. It is also possible to make the
16600 regex case insensitive by adding the flag "i" in <flags>. Since <flags> is a
16601 string, it is made up from the concatenation of all desired flags. Thus if
16602 both "i" and "g" are desired, using "gi" or "ig" will have the same effect.
Willy Tarreauef21fac2020-02-14 13:37:20 +010016603 The first use of this converter is to replace certain characters or sequence
16604 of characters with other ones.
16605
16606 It is highly recommended to enclose the regex part using protected quotes to
16607 improve clarity and never have a closing parenthesis from the regex mixed up
16608 with the parenthesis from the function. Just like in Bourne shell, the first
16609 level of quotes is processed when delimiting word groups on the line, a
16610 second level is usable for argument. It is recommended to use single quotes
16611 outside since these ones do not try to resolve backslashes nor dollar signs.
Willy Tarreau7eda8492015-01-20 19:47:06 +010016612
Willy Tarreaucd0d2ed2020-02-14 17:33:06 +010016613 Examples:
Willy Tarreau7eda8492015-01-20 19:47:06 +010016614
16615 # de-duplicate "/" in header "x-path".
16616 # input: x-path: /////a///b/c/xzxyz/
16617 # output: x-path: /a/b/c/xzxyz/
Willy Tarreauef21fac2020-02-14 13:37:20 +010016618 http-request set-header x-path "%[hdr(x-path),regsub('/+','/','g')]"
Willy Tarreau7eda8492015-01-20 19:47:06 +010016619
Willy Tarreaucd0d2ed2020-02-14 17:33:06 +010016620 # copy query string to x-query and drop all leading '?', ';' and '&'
16621 http-request set-header x-query "%[query,regsub([?;&]*,'')]"
16622
Jerome Magnin07e1e3c2020-02-16 19:20:19 +010016623 # capture groups and backreferences
16624 # both lines do the same.
Willy Tarreau465dc7d2020-10-08 18:05:56 +020016625 http-request redirect location %[url,'regsub("(foo|bar)([0-9]+)?","\2\1",i)']
Jerome Magnin07e1e3c2020-02-16 19:20:19 +010016626 http-request redirect location %[url,regsub(\"(foo|bar)([0-9]+)?\",\"\2\1\",i)]
16627
Thierry FOURNIER35ab2752015-05-28 13:22:03 +020016628capture-req(<id>)
16629 Capture the string entry in the request slot <id> and returns the entry as
16630 is. If the slot doesn't exist, the capture fails silently.
16631
16632 See also: "declare capture", "http-request capture",
Baptiste Assmann5ac425c2015-10-21 23:13:46 +020016633 "http-response capture", "capture.req.hdr" and
16634 "capture.res.hdr" (sample fetches).
Thierry FOURNIER35ab2752015-05-28 13:22:03 +020016635
16636capture-res(<id>)
16637 Capture the string entry in the response slot <id> and returns the entry as
16638 is. If the slot doesn't exist, the capture fails silently.
16639
16640 See also: "declare capture", "http-request capture",
Baptiste Assmann5ac425c2015-10-21 23:13:46 +020016641 "http-response capture", "capture.req.hdr" and
16642 "capture.res.hdr" (sample fetches).
Thierry FOURNIER35ab2752015-05-28 13:22:03 +020016643
Christopher Faulet568415a2020-04-01 17:24:47 +020016644rtrim(<chars>)
16645 Skips any characters from <chars> from the end of the string representation
16646 of the input sample.
16647
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020016648sdbm([<avalanche>])
16649 Hashes a binary input sample into an unsigned 32-bit quantity using the SDBM
16650 hash function. Optionally, it is possible to apply a full avalanche hash
16651 function to the output if the optional <avalanche> argument equals 1. This
16652 converter uses the same functions as used by the various hash-based load
16653 balancing algorithms, so it will provide exactly the same results. It is
16654 mostly intended for debugging, but can be used as a stick-table entry to
16655 collect rough statistics. It must not be used for security purposes as a
Emmanuel Hocdet50791a72018-03-21 11:19:01 +010016656 32-bit hash is trivial to break. See also "crc32", "djb2", "wt6", "crc32c",
16657 and the "hash-type" directive.
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020016658
Tim Duesterhusf38175c2020-06-09 11:48:42 +020016659secure_memcmp(<var>)
16660 Compares the contents of <var> with the input value. Both values are treated
16661 as a binary string. Returns a boolean indicating whether both binary strings
16662 match.
16663
16664 If both binary strings have the same length then the comparison will be
16665 performed in constant time.
16666
Daniel Corbett9f0843f2021-05-08 10:50:37 -040016667 Please note that this converter is only available when HAProxy has been
Tim Duesterhusf38175c2020-06-09 11:48:42 +020016668 compiled with USE_OPENSSL.
16669
16670 Example :
16671
16672 http-request set-var(txn.token) hdr(token)
16673 # Check whether the token sent by the client matches the secret token
16674 # value, without leaking the contents using a timing attack.
16675 acl token_given str(my_secret_token),secure_memcmp(txn.token)
16676
Tim Duesterhusef4e45c2021-01-21 17:40:50 +010016677set-var(<var>)
Davor Ocelice9ed2812017-12-25 17:49:28 +010016678 Sets a variable with the input content and returns the content on the output
16679 as-is. The variable keeps the value and the associated input type. The name of
16680 the variable starts with an indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016681 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016682 "sess" : the variable is shared with the whole session
16683 "txn" : the variable is shared with the transaction (request and
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020016684 response),
Daniel Schneller0b547052016-03-21 20:46:57 +010016685 "req" : the variable is shared only during request processing,
16686 "res" : the variable is shared only during response processing.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020016687 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016688 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020016689
Dragan Dosen6e5a9ca2017-10-24 09:18:23 +020016690sha1
Tim Duesterhusd4376302019-06-17 12:41:44 +020016691 Converts a binary input sample to a SHA-1 digest. The result is a binary
Dragan Dosen6e5a9ca2017-10-24 09:18:23 +020016692 sample with length of 20 bytes.
16693
Tim Duesterhusd4376302019-06-17 12:41:44 +020016694sha2([<bits>])
16695 Converts a binary input sample to a digest in the SHA-2 family. The result
16696 is a binary sample with length of <bits>/8 bytes.
16697
16698 Valid values for <bits> are 224, 256, 384, 512, each corresponding to
16699 SHA-<bits>. The default value is 256.
16700
Daniel Corbett9f0843f2021-05-08 10:50:37 -040016701 Please note that this converter is only available when HAProxy has been
Tim Duesterhusd4376302019-06-17 12:41:44 +020016702 compiled with USE_OPENSSL.
16703
Nenad Merdanovic177adc92019-08-27 01:58:13 +020016704srv_queue
16705 Takes an input value of type string, either a server name or <backend>/<server>
16706 format and returns the number of queued sessions on that server. Can be used
16707 in places where we want to look up queued sessions from a dynamic name, like a
16708 cookie value (e.g. req.cook(SRVID),srv_queue) and then make a decision to break
16709 persistence or direct a request elsewhere.
16710
Tim Duesterhusca097c12018-04-27 21:18:45 +020016711strcmp(<var>)
16712 Compares the contents of <var> with the input value of type string. Returns
16713 the result as a signed integer compatible with strcmp(3): 0 if both strings
16714 are identical. A value less than 0 if the left string is lexicographically
16715 smaller than the right string or if the left string is shorter. A value greater
16716 than 0 otherwise (right string greater than left string or the right string is
16717 shorter).
16718
Tim Duesterhusf38175c2020-06-09 11:48:42 +020016719 See also the secure_memcmp converter if you need to compare two binary
16720 strings in constant time.
16721
Tim Duesterhusca097c12018-04-27 21:18:45 +020016722 Example :
16723
16724 http-request set-var(txn.host) hdr(host)
16725 # Check whether the client is attempting domain fronting.
16726 acl ssl_sni_http_host_match ssl_fc_sni,strcmp(txn.host) eq 0
16727
16728
Willy Tarreau97707872015-01-27 15:12:13 +010016729sub(<value>)
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020016730 Subtracts <value> from the input value of type signed integer, and returns
16731 the result as an signed integer. Note: in order to subtract the input from
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016732 a constant, simply perform a "neg,add(value)". <value> can be a numeric value
Daniel Schneller0b547052016-03-21 20:46:57 +010016733 or a variable name. The name of the variable starts with an indication about
16734 its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010016735 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010016736 "sess" : the variable is shared with the whole session
16737 "txn" : the variable is shared with the transaction (request and
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016738 response),
Daniel Schneller0b547052016-03-21 20:46:57 +010016739 "req" : the variable is shared only during request processing,
16740 "res" : the variable is shared only during response processing.
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020016741 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010016742 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010016743
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016744table_bytes_in_rate(<table>)
16745 Uses the string representation of the input sample to perform a look up in
16746 the specified table. If the key is not found in the table, integer value zero
16747 is returned. Otherwise the converter returns the average client-to-server
16748 bytes rate associated with the input sample in the designated table, measured
16749 in amount of bytes over the period configured in the table. See also the
16750 sc_bytes_in_rate sample fetch keyword.
16751
16752
16753table_bytes_out_rate(<table>)
16754 Uses the string representation of the input sample to perform a look up in
16755 the specified table. If the key is not found in the table, integer value zero
16756 is returned. Otherwise the converter returns the average server-to-client
16757 bytes rate associated with the input sample in the designated table, measured
16758 in amount of bytes over the period configured in the table. See also the
16759 sc_bytes_out_rate sample fetch keyword.
16760
16761table_conn_cnt(<table>)
16762 Uses the string representation of the input sample to perform a look up in
16763 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016764 is returned. Otherwise the converter returns the cumulative number of incoming
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016765 connections associated with the input sample in the designated table. See
16766 also the sc_conn_cnt sample fetch keyword.
16767
16768table_conn_cur(<table>)
16769 Uses the string representation of the input sample to perform a look up in
16770 the specified table. If the key is not found in the table, integer value zero
16771 is returned. Otherwise the converter returns the current amount of concurrent
16772 tracked connections associated with the input sample in the designated table.
16773 See also the sc_conn_cur sample fetch keyword.
16774
16775table_conn_rate(<table>)
16776 Uses the string representation of the input sample to perform a look up in
16777 the specified table. If the key is not found in the table, integer value zero
16778 is returned. Otherwise the converter returns the average incoming connection
16779 rate associated with the input sample in the designated table. See also the
16780 sc_conn_rate sample fetch keyword.
16781
Thierry FOURNIER236657b2015-08-19 08:25:14 +020016782table_gpt0(<table>)
16783 Uses the string representation of the input sample to perform a look up in
16784 the specified table. If the key is not found in the table, boolean value zero
16785 is returned. Otherwise the converter returns the current value of the first
16786 general purpose tag associated with the input sample in the designated table.
16787 See also the sc_get_gpt0 sample fetch keyword.
16788
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016789table_gpc0(<table>)
16790 Uses the string representation of the input sample to perform a look up in
16791 the specified table. If the key is not found in the table, integer value zero
16792 is returned. Otherwise the converter returns the current value of the first
16793 general purpose counter associated with the input sample in the designated
16794 table. See also the sc_get_gpc0 sample fetch keyword.
16795
16796table_gpc0_rate(<table>)
16797 Uses the string representation of the input sample to perform a look up in
16798 the specified table. If the key is not found in the table, integer value zero
16799 is returned. Otherwise the converter returns the frequency which the gpc0
16800 counter was incremented over the configured period in the table, associated
16801 with the input sample in the designated table. See also the sc_get_gpc0_rate
16802 sample fetch keyword.
16803
Frédéric Lécaille6778b272018-01-29 15:22:53 +010016804table_gpc1(<table>)
16805 Uses the string representation of the input sample to perform a look up in
16806 the specified table. If the key is not found in the table, integer value zero
16807 is returned. Otherwise the converter returns the current value of the second
16808 general purpose counter associated with the input sample in the designated
16809 table. See also the sc_get_gpc1 sample fetch keyword.
16810
16811table_gpc1_rate(<table>)
16812 Uses the string representation of the input sample to perform a look up in
16813 the specified table. If the key is not found in the table, integer value zero
16814 is returned. Otherwise the converter returns the frequency which the gpc1
16815 counter was incremented over the configured period in the table, associated
16816 with the input sample in the designated table. See also the sc_get_gpc1_rate
16817 sample fetch keyword.
16818
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016819table_http_err_cnt(<table>)
16820 Uses the string representation of the input sample to perform a look up in
16821 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016822 is returned. Otherwise the converter returns the cumulative number of HTTP
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016823 errors associated with the input sample in the designated table. See also the
16824 sc_http_err_cnt sample fetch keyword.
16825
16826table_http_err_rate(<table>)
16827 Uses the string representation of the input sample to perform a look up in
16828 the specified table. If the key is not found in the table, integer value zero
16829 is returned. Otherwise the average rate of HTTP errors associated with the
16830 input sample in the designated table, measured in amount of errors over the
16831 period configured in the table. See also the sc_http_err_rate sample fetch
16832 keyword.
16833
Willy Tarreau826f3ab2021-02-10 12:07:15 +010016834table_http_fail_cnt(<table>)
16835 Uses the string representation of the input sample to perform a look up in
16836 the specified table. If the key is not found in the table, integer value zero
16837 is returned. Otherwise the converter returns the cumulative number of HTTP
16838 failures associated with the input sample in the designated table. See also
16839 the sc_http_fail_cnt sample fetch keyword.
16840
16841table_http_fail_rate(<table>)
16842 Uses the string representation of the input sample to perform a look up in
16843 the specified table. If the key is not found in the table, integer value zero
16844 is returned. Otherwise the average rate of HTTP failures associated with the
16845 input sample in the designated table, measured in amount of failures over the
16846 period configured in the table. See also the sc_http_fail_rate sample fetch
16847 keyword.
16848
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016849table_http_req_cnt(<table>)
16850 Uses the string representation of the input sample to perform a look up in
16851 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016852 is returned. Otherwise the converter returns the cumulative number of HTTP
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016853 requests associated with the input sample in the designated table. See also
16854 the sc_http_req_cnt sample fetch keyword.
16855
16856table_http_req_rate(<table>)
16857 Uses the string representation of the input sample to perform a look up in
16858 the specified table. If the key is not found in the table, integer value zero
16859 is returned. Otherwise the average rate of HTTP requests associated with the
16860 input sample in the designated table, measured in amount of requests over the
16861 period configured in the table. See also the sc_http_req_rate sample fetch
16862 keyword.
16863
16864table_kbytes_in(<table>)
16865 Uses the string representation of the input sample to perform a look up in
16866 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016867 is returned. Otherwise the converter returns the cumulative number of client-
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016868 to-server data associated with the input sample in the designated table,
16869 measured in kilobytes. The test is currently performed on 32-bit integers,
16870 which limits values to 4 terabytes. See also the sc_kbytes_in sample fetch
16871 keyword.
16872
16873table_kbytes_out(<table>)
16874 Uses the string representation of the input sample to perform a look up in
16875 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016876 is returned. Otherwise the converter returns the cumulative number of server-
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016877 to-client data associated with the input sample in the designated table,
16878 measured in kilobytes. The test is currently performed on 32-bit integers,
16879 which limits values to 4 terabytes. See also the sc_kbytes_out sample fetch
16880 keyword.
16881
16882table_server_id(<table>)
16883 Uses the string representation of the input sample to perform a look up in
16884 the specified table. If the key is not found in the table, integer value zero
16885 is returned. Otherwise the converter returns the server ID associated with
16886 the input sample in the designated table. A server ID is associated to a
16887 sample by a "stick" rule when a connection to a server succeeds. A server ID
16888 zero means that no server is associated with this key.
16889
16890table_sess_cnt(<table>)
16891 Uses the string representation of the input sample to perform a look up in
16892 the specified table. If the key is not found in the table, integer value zero
Davor Ocelice9ed2812017-12-25 17:49:28 +010016893 is returned. Otherwise the converter returns the cumulative number of incoming
Willy Tarreaud9f316a2014-07-10 14:03:38 +020016894 sessions associated with the input sample in the designated table. Note that
16895 a session here refers to an incoming connection being accepted by the
16896 "tcp-request connection" rulesets. See also the sc_sess_cnt sample fetch
16897 keyword.
16898
16899table_sess_rate(<table>)
16900 Uses the string representation of the input sample to perform a look up in
16901 the specified table. If the key is not found in the table, integer value zero
16902 is returned. Otherwise the converter returns the average incoming session
16903 rate associated with the input sample in the designated table. Note that a
16904 session here refers to an incoming connection being accepted by the
16905 "tcp-request connection" rulesets. See also the sc_sess_rate sample fetch
16906 keyword.
16907
16908table_trackers(<table>)
16909 Uses the string representation of the input sample to perform a look up in
16910 the specified table. If the key is not found in the table, integer value zero
16911 is returned. Otherwise the converter returns the current amount of concurrent
16912 connections tracking the same key as the input sample in the designated
16913 table. It differs from table_conn_cur in that it does not rely on any stored
16914 information but on the table's reference count (the "use" value which is
16915 returned by "show table" on the CLI). This may sometimes be more suited for
16916 layer7 tracking. It can be used to tell a server how many concurrent
16917 connections there are from a given address for example. See also the
16918 sc_trackers sample fetch keyword.
16919
Moemen MHEDHBI92f7d432021-04-01 20:53:59 +020016920ub64dec
16921 This converter is the base64url variant of b64dec converter. base64url
16922 encoding is the "URL and Filename Safe Alphabet" variant of base64 encoding.
16923 It is also the encoding used in JWT (JSON Web Token) standard.
16924
16925 Example:
16926 # Decoding a JWT payload:
16927 http-request set-var(txn.token_payload) req.hdr(Authorization),word(2,.),ub64dec
16928
16929ub64enc
16930 This converter is the base64url variant of base64 converter.
16931
Willy Tarreauffcb2e42014-07-10 16:29:08 +020016932upper
16933 Convert a string sample to upper case. This can only be placed after a string
16934 sample fetch function or after a transformation keyword returning a string
16935 type. The result is of type string.
16936
Willy Tarreau62ba9ba2020-04-23 17:54:47 +020016937url_dec([<in_form>])
16938 Takes an url-encoded string provided as input and returns the decoded version
16939 as output. The input and the output are of type string. If the <in_form>
16940 argument is set to a non-zero integer value, the input string is assumed to
16941 be part of a form or query string and the '+' character will be turned into a
16942 space (' '). Otherwise this will only happen after a question mark indicating
16943 a query string ('?').
Thierry FOURNIER82ff3c92015-05-07 15:46:20 +020016944
William Dauchy888b0ae2021-01-06 23:39:50 +010016945url_enc([<enc_type>])
16946 Takes a string provided as input and returns the encoded version as output.
16947 The input and the output are of type string. By default the type of encoding
16948 is meant for `query` type. There is no other type supported for now but the
16949 optional argument is here for future changes.
16950
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016951ungrpc(<field_number>,[<field_type>])
Frédéric Lécaille50290fb2019-02-27 14:34:51 +010016952 This extracts the protocol buffers message field in raw mode of an input binary
Frédéric Lécaillebfe61382019-03-06 14:34:36 +010016953 sample representation of a gRPC message with <field_number> as field number
16954 (dotted notation) if <field_type> is not present, or as an integer sample if this
16955 field is present.
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016956 The list of the authorized types is the following one: "int32", "int64", "uint32",
16957 "uint64", "sint32", "sint64", "bool", "enum" for the "varint" wire type 0
16958 "fixed64", "sfixed64", "double" for the 64bit wire type 1, "fixed32", "sfixed32",
16959 "float" for the wire type 5. Note that "string" is considered as a length-delimited
Frédéric Lécaille93d33162019-03-06 09:35:59 +010016960 type, so it does not require any <field_type> argument to be extracted.
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016961 More information may be found here about the protocol buffers message field types:
16962 https://developers.google.com/protocol-buffers/docs/encoding
Frédéric Lécaille50290fb2019-02-27 14:34:51 +010016963
16964 Example:
16965 // with such a protocol buffer .proto file content adapted from
16966 // https://github.com/grpc/grpc/blob/master/examples/protos/route_guide.proto
16967
16968 message Point {
16969 int32 latitude = 1;
16970 int32 longitude = 2;
16971 }
16972
16973 message PPoint {
16974 Point point = 59;
16975 }
16976
16977 message Rectangle {
16978 // One corner of the rectangle.
16979 PPoint lo = 48;
16980 // The other corner of the rectangle.
16981 PPoint hi = 49;
16982 }
16983
Peter Gervaidf4c9d22020-06-11 18:05:11 +020016984 let's say a body request is made of a "Rectangle" object value (two PPoint
16985 protocol buffers messages), the four protocol buffers fields could be
16986 extracted with these "ungrpc" directives:
Frédéric Lécaille50290fb2019-02-27 14:34:51 +010016987
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016988 req.body,ungrpc(48.59.1,int32) # "latitude" of "lo" first PPoint
16989 req.body,ungrpc(48.59.2,int32) # "longitude" of "lo" first PPoint
John Roeslerfb2fce12019-07-10 15:45:51 -050016990 req.body,ungrpc(49.59.1,int32) # "latitude" of "hi" second PPoint
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016991 req.body,ungrpc(49.59.2,int32) # "longitude" of "hi" second PPoint
16992
Peter Gervaidf4c9d22020-06-11 18:05:11 +020016993 We could also extract the intermediary 48.59 field as a binary sample as follows:
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016994
Frédéric Lécaille93d33162019-03-06 09:35:59 +010016995 req.body,ungrpc(48.59)
Frédéric Lécaille756d97f2019-03-04 19:03:48 +010016996
Peter Gervaidf4c9d22020-06-11 18:05:11 +020016997 As a gRPC message is always made of a gRPC header followed by protocol buffers
16998 messages, in the previous example the "latitude" of "lo" first PPoint
16999 could be extracted with these equivalent directives:
Frédéric Lécaillebfe61382019-03-06 14:34:36 +010017000
17001 req.body,ungrpc(48.59),protobuf(1,int32)
17002 req.body,ungrpc(48),protobuf(59.1,int32)
17003 req.body,ungrpc(48),protobuf(59),protobuf(1,int32)
17004
Peter Gervaidf4c9d22020-06-11 18:05:11 +020017005 Note that the first convert must be "ungrpc", the remaining ones must be
17006 "protobuf" and only the last one may have or not a second argument to
17007 interpret the previous binary sample.
Frédéric Lécaillebfe61382019-03-06 14:34:36 +010017008
Frédéric Lécaille50290fb2019-02-27 14:34:51 +010017009
Tim Duesterhusef4e45c2021-01-21 17:40:50 +010017010unset-var(<var>)
Christopher Faulet85d79c92016-11-09 16:54:56 +010017011 Unsets a variable if the input content is defined. The name of the variable
17012 starts with an indication about its scope. The scopes allowed are:
17013 "proc" : the variable is shared with the whole process
17014 "sess" : the variable is shared with the whole session
17015 "txn" : the variable is shared with the transaction (request and
17016 response),
17017 "req" : the variable is shared only during request processing,
17018 "res" : the variable is shared only during response processing.
17019 This prefix is followed by a name. The separator is a '.'. The name may only
17020 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
17021
Willy Tarreau0dbfdba2014-07-10 16:37:47 +020017022utime(<format>[,<offset>])
17023 Converts an integer supposed to contain a date since epoch to a string
17024 representing this date in UTC time using a format defined by the <format>
17025 string using strftime(3). The purpose is to allow any date format to be used
17026 in logs. An optional <offset> in seconds may be applied to the input date
17027 (positive or negative). See the strftime() man page for the format supported
17028 by your operating system. See also the ltime converter.
17029
17030 Example :
17031
17032 # Emit two colons, one with the UTC time and another with ip:port
Davor Ocelice9ed2812017-12-25 17:49:28 +010017033 # e.g. 20140710162350 127.0.0.1:57325
Willy Tarreau0dbfdba2014-07-10 16:37:47 +020017034 log-format %[date,utime(%Y%m%d%H%M%S)]\ %ci:%cp
17035
Marcin Deranek9631a282018-04-16 14:30:46 +020017036word(<index>,<delimiters>[,<count>])
17037 Extracts the nth word counting from the beginning (positive index) or from
17038 the end (negative index) considering given delimiters from an input string.
17039 Indexes start at 1 or -1 and delimiters are a string formatted list of chars.
Jerome Magnin88209322020-01-28 13:33:44 +010017040 Delimiters at the beginning or end of the input string are ignored.
Marcin Deranek9631a282018-04-16 14:30:46 +020017041 Optionally you can specify <count> of words to extract (default: 1).
17042 Value of 0 indicates extraction of all remaining words.
17043
17044 Example :
17045 str(f1_f2_f3__f5),word(4,_) # f5
17046 str(f1_f2_f3__f5),word(2,_,0) # f2_f3__f5
17047 str(f1_f2_f3__f5),word(3,_,2) # f3__f5
17048 str(f1_f2_f3__f5),word(-2,_,3) # f1_f2_f3
17049 str(f1_f2_f3__f5),word(-3,_,0) # f1_f2
Jerome Magnin88209322020-01-28 13:33:44 +010017050 str(/f1/f2/f3/f4),word(1,/) # f1
Emeric Brunc9a0f6d2014-11-25 14:09:01 +010017051
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020017052wt6([<avalanche>])
17053 Hashes a binary input sample into an unsigned 32-bit quantity using the WT6
17054 hash function. Optionally, it is possible to apply a full avalanche hash
17055 function to the output if the optional <avalanche> argument equals 1. This
17056 converter uses the same functions as used by the various hash-based load
17057 balancing algorithms, so it will provide exactly the same results. It is
17058 mostly intended for debugging, but can be used as a stick-table entry to
17059 collect rough statistics. It must not be used for security purposes as a
Emmanuel Hocdet50791a72018-03-21 11:19:01 +010017060 32-bit hash is trivial to break. See also "crc32", "djb2", "sdbm", "crc32c",
17061 and the "hash-type" directive.
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020017062
Willy Tarreau97707872015-01-27 15:12:13 +010017063xor(<value>)
17064 Performs a bitwise "XOR" (exclusive OR) between <value> and the input value
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020017065 of type signed integer, and returns the result as an signed integer.
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020017066 <value> can be a numeric value or a variable name. The name of the variable
Daniel Schneller0b547052016-03-21 20:46:57 +010017067 starts with an indication about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010017068 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010017069 "sess" : the variable is shared with the whole session
17070 "txn" : the variable is shared with the transaction (request and
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020017071 response),
Daniel Schneller0b547052016-03-21 20:46:57 +010017072 "req" : the variable is shared only during request processing,
17073 "res" : the variable is shared only during response processing.
Thierry FOURNIER5d86fae2015-07-07 21:10:16 +020017074 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010017075 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Willy Tarreau97707872015-01-27 15:12:13 +010017076
Dragan Dosen04bf0cc2020-12-22 21:44:33 +010017077xxh3([<seed>])
17078 Hashes a binary input sample into a signed 64-bit quantity using the XXH3
17079 64-bit variant of the XXhash hash function. This hash supports a seed which
17080 defaults to zero but a different value maybe passed as the <seed> argument.
17081 This hash is known to be very good and very fast so it can be used to hash
17082 URLs and/or URL parameters for use as stick-table keys to collect statistics
17083 with a low collision rate, though care must be taken as the algorithm is not
17084 considered as cryptographically secure.
17085
Thierry FOURNIER01e09742016-12-26 11:46:11 +010017086xxh32([<seed>])
17087 Hashes a binary input sample into an unsigned 32-bit quantity using the 32-bit
17088 variant of the XXHash hash function. This hash supports a seed which defaults
17089 to zero but a different value maybe passed as the <seed> argument. This hash
17090 is known to be very good and very fast so it can be used to hash URLs and/or
17091 URL parameters for use as stick-table keys to collect statistics with a low
17092 collision rate, though care must be taken as the algorithm is not considered
17093 as cryptographically secure.
17094
17095xxh64([<seed>])
17096 Hashes a binary input sample into a signed 64-bit quantity using the 64-bit
17097 variant of the XXHash hash function. This hash supports a seed which defaults
17098 to zero but a different value maybe passed as the <seed> argument. This hash
17099 is known to be very good and very fast so it can be used to hash URLs and/or
17100 URL parameters for use as stick-table keys to collect statistics with a low
17101 collision rate, though care must be taken as the algorithm is not considered
17102 as cryptographically secure.
17103
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010017104
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200171057.3.2. Fetching samples from internal states
Willy Tarreau74ca5042013-06-11 23:12:07 +020017106--------------------------------------------
17107
17108A first set of sample fetch methods applies to internal information which does
17109not even relate to any client information. These ones are sometimes used with
17110"monitor-fail" directives to report an internal status to external watchers.
17111The sample fetch methods described in this section are usable anywhere.
17112
17113always_false : boolean
17114 Always returns the boolean "false" value. It may be used with ACLs as a
17115 temporary replacement for another one when adjusting configurations.
17116
17117always_true : boolean
17118 Always returns the boolean "true" value. It may be used with ACLs as a
17119 temporary replacement for another one when adjusting configurations.
17120
17121avg_queue([<backend>]) : integer
Willy Tarreaud63335a2010-02-26 12:56:52 +010017122 Returns the total number of queued connections of the designated backend
Willy Tarreau74ca5042013-06-11 23:12:07 +020017123 divided by the number of active servers. The current backend is used if no
17124 backend is specified. This is very similar to "queue" except that the size of
17125 the farm is considered, in order to give a more accurate measurement of the
17126 time it may take for a new connection to be processed. The main usage is with
17127 ACL to return a sorry page to new users when it becomes certain they will get
17128 a degraded service, or to pass to the backend servers in a header so that
17129 they decide to work in degraded mode or to disable some functions to speed up
17130 the processing a bit. Note that in the event there would not be any active
17131 server anymore, twice the number of queued connections would be considered as
17132 the measured value. This is a fair estimate, as we expect one server to get
17133 back soon anyway, but we still prefer to send new traffic to another backend
17134 if in better shape. See also the "queue", "be_conn", and "be_sess_rate"
17135 sample fetches.
Krzysztof Piotr Oledzki346f76d2010-01-12 21:59:30 +010017136
Willy Tarreau74ca5042013-06-11 23:12:07 +020017137be_conn([<backend>]) : integer
Willy Tarreaua36af912009-10-10 12:02:45 +020017138 Applies to the number of currently established connections on the backend,
17139 possibly including the connection being evaluated. If no backend name is
17140 specified, the current one is used. But it is also possible to check another
17141 backend. It can be used to use a specific farm when the nominal one is full.
Patrick Hemmer4cdf3ab2018-06-14 17:10:27 -040017142 See also the "fe_conn", "queue", "be_conn_free", and "be_sess_rate" criteria.
17143
17144be_conn_free([<backend>]) : integer
17145 Returns an integer value corresponding to the number of available connections
17146 across available servers in the backend. Queue slots are not included. Backup
17147 servers are also not included, unless all other servers are down. If no
17148 backend name is specified, the current one is used. But it is also possible
17149 to check another backend. It can be used to use a specific farm when the
Patrick Hemmer155e93e2018-06-14 18:01:35 -040017150 nominal one is full. See also the "be_conn", "connslots", and "srv_conn_free"
17151 criteria.
Patrick Hemmer4cdf3ab2018-06-14 17:10:27 -040017152
17153 OTHER CAVEATS AND NOTES: if any of the server maxconn, or maxqueue is 0
17154 (meaning unlimited), then this fetch clearly does not make sense, in which
17155 case the value returned will be -1.
Willy Tarreau6a06a402007-07-15 20:15:28 +020017156
Willy Tarreau74ca5042013-06-11 23:12:07 +020017157be_sess_rate([<backend>]) : integer
17158 Returns an integer value corresponding to the sessions creation rate on the
17159 backend, in number of new sessions per second. This is used with ACLs to
17160 switch to an alternate backend when an expensive or fragile one reaches too
Davor Ocelice9ed2812017-12-25 17:49:28 +010017161 high a session rate, or to limit abuse of service (e.g. prevent sucking of an
Willy Tarreau74ca5042013-06-11 23:12:07 +020017162 online dictionary). It can also be useful to add this element to logs using a
17163 log-format directive.
Willy Tarreaud63335a2010-02-26 12:56:52 +010017164
17165 Example :
17166 # Redirect to an error page if the dictionary is requested too often
17167 backend dynamic
17168 mode http
17169 acl being_scanned be_sess_rate gt 100
17170 redirect location /denied.html if being_scanned
Willy Tarreau0ba27502007-12-24 16:55:16 +010017171
Davor Ocelice9ed2812017-12-25 17:49:28 +010017172bin(<hex>) : bin
Thierry FOURNIERcc103292015-06-06 19:30:17 +020017173 Returns a binary chain. The input is the hexadecimal representation
17174 of the string.
17175
17176bool(<bool>) : bool
17177 Returns a boolean value. <bool> can be 'true', 'false', '1' or '0'.
17178 'false' and '0' are the same. 'true' and '1' are the same.
17179
Willy Tarreau74ca5042013-06-11 23:12:07 +020017180connslots([<backend>]) : integer
17181 Returns an integer value corresponding to the number of connection slots
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030017182 still available in the backend, by totaling the maximum amount of
Willy Tarreau74ca5042013-06-11 23:12:07 +020017183 connections on all servers and the maximum queue size. This is probably only
17184 used with ACLs.
Tait Clarridge7896d522012-12-05 21:39:31 -050017185
Jeffrey 'jf' Lim5051d7b2008-09-04 01:03:03 +080017186 The basic idea here is to be able to measure the number of connection "slots"
Willy Tarreau55165fe2009-05-10 12:02:55 +020017187 still available (connection + queue), so that anything beyond that (intended
Jeffrey 'jf' Lim5051d7b2008-09-04 01:03:03 +080017188 usage; see "use_backend" keyword) can be redirected to a different backend.
17189
Willy Tarreau55165fe2009-05-10 12:02:55 +020017190 'connslots' = number of available server connection slots, + number of
17191 available server queue slots.
Jeffrey 'jf' Lim5051d7b2008-09-04 01:03:03 +080017192
Willy Tarreaua36af912009-10-10 12:02:45 +020017193 Note that while "fe_conn" may be used, "connslots" comes in especially
Willy Tarreau55165fe2009-05-10 12:02:55 +020017194 useful when you have a case of traffic going to one single ip, splitting into
Willy Tarreau74ca5042013-06-11 23:12:07 +020017195 multiple backends (perhaps using ACLs to do name-based load balancing) and
Willy Tarreau55165fe2009-05-10 12:02:55 +020017196 you want to be able to differentiate between different backends, and their
Davor Ocelice9ed2812017-12-25 17:49:28 +010017197 available "connslots". Also, whereas "nbsrv" only measures servers that are
Willy Tarreau74ca5042013-06-11 23:12:07 +020017198 actually *down*, this fetch is more fine-grained and looks into the number of
Willy Tarreaua36af912009-10-10 12:02:45 +020017199 available connection slots as well. See also "queue" and "avg_queue".
Jeffrey 'jf' Lim5051d7b2008-09-04 01:03:03 +080017200
Willy Tarreau55165fe2009-05-10 12:02:55 +020017201 OTHER CAVEATS AND NOTES: at this point in time, the code does not take care
17202 of dynamic connections. Also, if any of the server maxconn, or maxqueue is 0,
Willy Tarreau74ca5042013-06-11 23:12:07 +020017203 then this fetch clearly does not make sense, in which case the value returned
Willy Tarreau55165fe2009-05-10 12:02:55 +020017204 will be -1.
Jeffrey 'jf' Lim5051d7b2008-09-04 01:03:03 +080017205
Willy Tarreau70fe9442018-11-22 16:07:39 +010017206cpu_calls : integer
17207 Returns the number of calls to the task processing the stream or current
17208 request since it was allocated. This number is reset for each new request on
17209 the same connections in case of HTTP keep-alive. This value should usually be
17210 low and stable (around 2 calls for a typically simple request) but may become
17211 high if some processing (compression, caching or analysis) is performed. This
17212 is purely for performance monitoring purposes.
17213
17214cpu_ns_avg : integer
17215 Returns the average number of nanoseconds spent in each call to the task
17216 processing the stream or current request. This number is reset for each new
17217 request on the same connections in case of HTTP keep-alive. This value
17218 indicates the overall cost of processing the request or the connection for
17219 each call. There is no good nor bad value but the time spent in a call
17220 automatically causes latency for other processing (see lat_ns_avg below),
17221 and may affect other connection's apparent response time. Certain operations
17222 like compression, complex regex matching or heavy Lua operations may directly
17223 affect this value, and having it in the logs will make it easier to spot the
17224 faulty processing that needs to be fixed to recover decent performance.
17225 Note: this value is exactly cpu_ns_tot divided by cpu_calls.
17226
17227cpu_ns_tot : integer
17228 Returns the total number of nanoseconds spent in each call to the task
17229 processing the stream or current request. This number is reset for each new
17230 request on the same connections in case of HTTP keep-alive. This value
17231 indicates the overall cost of processing the request or the connection for
17232 each call. There is no good nor bad value but the time spent in a call
17233 automatically causes latency for other processing (see lat_ns_avg below),
17234 induces CPU costs on the machine, and may affect other connection's apparent
17235 response time. Certain operations like compression, complex regex matching or
17236 heavy Lua operations may directly affect this value, and having it in the
17237 logs will make it easier to spot the faulty processing that needs to be fixed
17238 to recover decent performance. The value may be artificially high due to a
17239 high cpu_calls count, for example when processing many HTTP chunks, and for
17240 this reason it is often preferred to log cpu_ns_avg instead.
17241
Cyril Bonté6bcd1822019-11-05 23:13:59 +010017242date([<offset>],[<unit>]) : integer
Willy Tarreau6236d3a2013-07-25 14:28:25 +020017243 Returns the current date as the epoch (number of seconds since 01/01/1970).
Damien Claisseae6f1252019-10-30 15:57:28 +000017244
17245 If an offset value is specified, then it is added to the current date before
17246 returning the value. This is particularly useful to compute relative dates,
17247 as both positive and negative offsets are allowed.
Willy Tarreau276fae92013-07-25 14:36:01 +020017248 It is useful combined with the http_date converter.
17249
Damien Claisseae6f1252019-10-30 15:57:28 +000017250 <unit> is facultative, and can be set to "s" for seconds (default behavior),
17251 "ms" for milliseconds or "us" for microseconds.
17252 If unit is set, return value is an integer reflecting either seconds,
17253 milliseconds or microseconds since epoch, plus offset.
17254 It is useful when a time resolution of less than a second is needed.
17255
Willy Tarreau276fae92013-07-25 14:36:01 +020017256 Example :
17257
17258 # set an expires header to now+1 hour in every response
17259 http-response set-header Expires %[date(3600),http_date]
Willy Tarreau6236d3a2013-07-25 14:28:25 +020017260
Damien Claisseae6f1252019-10-30 15:57:28 +000017261 # set an expires header to now+1 hour in every response, with
17262 # millisecond granularity
17263 http-response set-header Expires %[date(3600000,ms),http_date(0,ms)]
17264
Etienne Carrierea792a0a2018-01-17 13:43:24 +010017265date_us : integer
17266 Return the microseconds part of the date (the "second" part is returned by
17267 date sample). This sample is coherent with the date sample as it is comes
17268 from the same timeval structure.
17269
Willy Tarreaud716f9b2017-10-13 11:03:15 +020017270distcc_body(<token>[,<occ>]) : binary
17271 Parses a distcc message and returns the body associated to occurrence #<occ>
17272 of the token <token>. Occurrences start at 1, and when unspecified, any may
17273 match though in practice only the first one is checked for now. This can be
17274 used to extract file names or arguments in files built using distcc through
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017275 HAProxy. Please refer to distcc's protocol documentation for the complete
Willy Tarreaud716f9b2017-10-13 11:03:15 +020017276 list of supported tokens.
17277
17278distcc_param(<token>[,<occ>]) : integer
17279 Parses a distcc message and returns the parameter associated to occurrence
17280 #<occ> of the token <token>. Occurrences start at 1, and when unspecified,
17281 any may match though in practice only the first one is checked for now. This
17282 can be used to extract certain information such as the protocol version, the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017283 file size or the argument in files built using distcc through HAProxy.
Willy Tarreaud716f9b2017-10-13 11:03:15 +020017284 Another use case consists in waiting for the start of the preprocessed file
17285 contents before connecting to the server to avoid keeping idle connections.
17286 Please refer to distcc's protocol documentation for the complete list of
17287 supported tokens.
17288
17289 Example :
17290 # wait up to 20s for the pre-processed file to be uploaded
17291 tcp-request inspect-delay 20s
17292 tcp-request content accept if { distcc_param(DOTI) -m found }
17293 # send large files to the big farm
17294 use_backend big_farm if { distcc_param(DOTI) gt 1000000 }
17295
Willy Tarreau595ec542013-06-12 21:34:28 +020017296env(<name>) : string
17297 Returns a string containing the value of environment variable <name>. As a
17298 reminder, environment variables are per-process and are sampled when the
17299 process starts. This can be useful to pass some information to a next hop
17300 server, or with ACLs to take specific action when the process is started a
17301 certain way.
17302
17303 Examples :
17304 # Pass the Via header to next hop with the local hostname in it
17305 http-request add-header Via 1.1\ %[env(HOSTNAME)]
17306
17307 # reject cookie-less requests when the STOP environment variable is set
17308 http-request deny if !{ cook(SESSIONID) -m found } { env(STOP) -m found }
17309
Willy Tarreau74ca5042013-06-11 23:12:07 +020017310fe_conn([<frontend>]) : integer
17311 Returns the number of currently established connections on the frontend,
Willy Tarreaud63335a2010-02-26 12:56:52 +010017312 possibly including the connection being evaluated. If no frontend name is
17313 specified, the current one is used. But it is also possible to check another
Willy Tarreau74ca5042013-06-11 23:12:07 +020017314 frontend. It can be used to return a sorry page before hard-blocking, or to
17315 use a specific backend to drain new requests when the farm is considered
Davor Ocelice9ed2812017-12-25 17:49:28 +010017316 full. This is mostly used with ACLs but can also be used to pass some
Willy Tarreau74ca5042013-06-11 23:12:07 +020017317 statistics to servers in HTTP headers. See also the "dst_conn", "be_conn",
17318 "fe_sess_rate" fetches.
Willy Tarreaua36af912009-10-10 12:02:45 +020017319
Nenad Merdanovicad9a7e92016-10-03 04:57:37 +020017320fe_req_rate([<frontend>]) : integer
17321 Returns an integer value corresponding to the number of HTTP requests per
17322 second sent to a frontend. This number can differ from "fe_sess_rate" in
17323 situations where client-side keep-alive is enabled.
17324
Willy Tarreau74ca5042013-06-11 23:12:07 +020017325fe_sess_rate([<frontend>]) : integer
17326 Returns an integer value corresponding to the sessions creation rate on the
17327 frontend, in number of new sessions per second. This is used with ACLs to
17328 limit the incoming session rate to an acceptable range in order to prevent
17329 abuse of service at the earliest moment, for example when combined with other
17330 layer 4 ACLs in order to force the clients to wait a bit for the rate to go
17331 down below the limit. It can also be useful to add this element to logs using
17332 a log-format directive. See also the "rate-limit sessions" directive for use
17333 in frontends.
Willy Tarreau079ff0a2009-03-05 21:34:28 +010017334
17335 Example :
17336 # This frontend limits incoming mails to 10/s with a max of 100
17337 # concurrent connections. We accept any connection below 10/s, and
17338 # force excess clients to wait for 100 ms. Since clients are limited to
17339 # 100 max, there cannot be more than 10 incoming mails per second.
17340 frontend mail
17341 bind :25
17342 mode tcp
17343 maxconn 100
17344 acl too_fast fe_sess_rate ge 10
17345 tcp-request inspect-delay 100ms
17346 tcp-request content accept if ! too_fast
17347 tcp-request content accept if WAIT_END
Willy Tarreaud72758d2010-01-12 10:42:19 +010017348
Nenad Merdanovic807a6e72017-03-12 22:00:00 +010017349hostname : string
17350 Returns the system hostname.
17351
Thierry FOURNIER07ee64e2015-07-06 23:43:03 +020017352int(<integer>) : signed integer
17353 Returns a signed integer.
17354
Thierry FOURNIERcc103292015-06-06 19:30:17 +020017355ipv4(<ipv4>) : ipv4
17356 Returns an ipv4.
17357
17358ipv6(<ipv6>) : ipv6
17359 Returns an ipv6.
17360
Willy Tarreau70fe9442018-11-22 16:07:39 +010017361lat_ns_avg : integer
17362 Returns the average number of nanoseconds spent between the moment the task
17363 handling the stream is woken up and the moment it is effectively called. This
17364 number is reset for each new request on the same connections in case of HTTP
17365 keep-alive. This value indicates the overall latency inflicted to the current
17366 request by all other requests being processed in parallel, and is a direct
17367 indicator of perceived performance due to noisy neighbours. In order to keep
17368 the value low, it is possible to reduce the scheduler's run queue depth using
17369 "tune.runqueue-depth", to reduce the number of concurrent events processed at
17370 once using "tune.maxpollevents", to decrease the stream's nice value using
Willy Tarreaue7723bd2020-06-24 11:11:02 +020017371 the "nice" option on the "bind" lines or in the frontend, to enable low
17372 latency scheduling using "tune.sched.low-latency", or to look for other heavy
17373 requests in logs (those exhibiting large values of "cpu_ns_avg"), whose
17374 processing needs to be adjusted or fixed. Compression of large buffers could
17375 be a culprit, like heavy regex or long lists of regex. Note: this value is
17376 exactly lat_ns_tot divided by cpu_calls.
Willy Tarreau70fe9442018-11-22 16:07:39 +010017377
17378lat_ns_tot : integer
17379 Returns the total number of nanoseconds spent between the moment the task
17380 handling the stream is woken up and the moment it is effectively called. This
17381 number is reset for each new request on the same connections in case of HTTP
17382 keep-alive. This value indicates the overall latency inflicted to the current
17383 request by all other requests being processed in parallel, and is a direct
17384 indicator of perceived performance due to noisy neighbours. In order to keep
17385 the value low, it is possible to reduce the scheduler's run queue depth using
17386 "tune.runqueue-depth", to reduce the number of concurrent events processed at
17387 once using "tune.maxpollevents", to decrease the stream's nice value using
Willy Tarreaue7723bd2020-06-24 11:11:02 +020017388 the "nice" option on the "bind" lines or in the frontend, to enable low
17389 latency scheduling using "tune.sched.low-latency", or to look for other heavy
17390 requests in logs (those exhibiting large values of "cpu_ns_avg"), whose
17391 processing needs to be adjusted or fixed. Compression of large buffers could
17392 be a culprit, like heavy regex or long lists of regex. Note: while it
Willy Tarreau70fe9442018-11-22 16:07:39 +010017393 may intuitively seem that the total latency adds to a transfer time, it is
17394 almost never true because while a task waits for the CPU, network buffers
17395 continue to fill up and the next call will process more at once. The value
17396 may be artificially high due to a high cpu_calls count, for example when
17397 processing many HTTP chunks, and for this reason it is often preferred to log
17398 lat_ns_avg instead, which is a more relevant performance indicator.
17399
Thierry FOURNIERcc103292015-06-06 19:30:17 +020017400meth(<method>) : method
17401 Returns a method.
17402
Willy Tarreau0f30d262014-11-24 16:02:05 +010017403nbproc : integer
17404 Returns an integer value corresponding to the number of processes that were
17405 started (it equals the global "nbproc" setting). This is useful for logging
17406 and debugging purposes.
17407
Willy Tarreau74ca5042013-06-11 23:12:07 +020017408nbsrv([<backend>]) : integer
17409 Returns an integer value corresponding to the number of usable servers of
17410 either the current backend or the named backend. This is mostly used with
17411 ACLs but can also be useful when added to logs. This is normally used to
Willy Tarreaud63335a2010-02-26 12:56:52 +010017412 switch to an alternate backend when the number of servers is too low to
17413 to handle some load. It is useful to report a failure when combined with
17414 "monitor fail".
Willy Tarreau079ff0a2009-03-05 21:34:28 +010017415
Patrick Hemmerfabb24f2018-08-13 14:07:57 -040017416prio_class : integer
17417 Returns the priority class of the current session for http mode or connection
17418 for tcp mode. The value will be that set by the last call to "http-request
17419 set-priority-class" or "tcp-request content set-priority-class".
17420
17421prio_offset : integer
17422 Returns the priority offset of the current session for http mode or
17423 connection for tcp mode. The value will be that set by the last call to
17424 "http-request set-priority-offset" or "tcp-request content
17425 set-priority-offset".
17426
Willy Tarreau0f30d262014-11-24 16:02:05 +010017427proc : integer
17428 Returns an integer value corresponding to the position of the process calling
17429 the function, between 1 and global.nbproc. This is useful for logging and
17430 debugging purposes.
17431
Willy Tarreau74ca5042013-06-11 23:12:07 +020017432queue([<backend>]) : integer
Willy Tarreaud63335a2010-02-26 12:56:52 +010017433 Returns the total number of queued connections of the designated backend,
17434 including all the connections in server queues. If no backend name is
17435 specified, the current one is used, but it is also possible to check another
Willy Tarreau74ca5042013-06-11 23:12:07 +020017436 one. This is useful with ACLs or to pass statistics to backend servers. This
17437 can be used to take actions when queuing goes above a known level, generally
17438 indicating a surge of traffic or a massive slowdown on the servers. One
17439 possible action could be to reject new users but still accept old ones. See
17440 also the "avg_queue", "be_conn", and "be_sess_rate" fetches.
17441
Willy Tarreau84310e22014-02-14 11:59:04 +010017442rand([<range>]) : integer
17443 Returns a random integer value within a range of <range> possible values,
17444 starting at zero. If the range is not specified, it defaults to 2^32, which
17445 gives numbers between 0 and 4294967295. It can be useful to pass some values
17446 needed to take some routing decisions for example, or just for debugging
17447 purposes. This random must not be used for security purposes.
17448
Willy Tarreau74ca5042013-06-11 23:12:07 +020017449srv_conn([<backend>/]<server>) : integer
17450 Returns an integer value corresponding to the number of currently established
17451 connections on the designated server, possibly including the connection being
17452 evaluated. If <backend> is omitted, then the server is looked up in the
17453 current backend. It can be used to use a specific farm when one server is
17454 full, or to inform the server about our view of the number of active
Patrick Hemmer155e93e2018-06-14 18:01:35 -040017455 connections with it. See also the "fe_conn", "be_conn", "queue", and
17456 "srv_conn_free" fetch methods.
17457
17458srv_conn_free([<backend>/]<server>) : integer
17459 Returns an integer value corresponding to the number of available connections
17460 on the designated server, possibly including the connection being evaluated.
17461 The value does not include queue slots. If <backend> is omitted, then the
17462 server is looked up in the current backend. It can be used to use a specific
17463 farm when one server is full, or to inform the server about our view of the
17464 number of active connections with it. See also the "be_conn_free" and
17465 "srv_conn" fetch methods.
17466
17467 OTHER CAVEATS AND NOTES: If the server maxconn is 0, then this fetch clearly
17468 does not make sense, in which case the value returned will be -1.
Willy Tarreau74ca5042013-06-11 23:12:07 +020017469
17470srv_is_up([<backend>/]<server>) : boolean
17471 Returns true when the designated server is UP, and false when it is either
17472 DOWN or in maintenance mode. If <backend> is omitted, then the server is
17473 looked up in the current backend. It is mainly used to take action based on
Davor Ocelice9ed2812017-12-25 17:49:28 +010017474 an external status reported via a health check (e.g. a geographical site's
Willy Tarreau74ca5042013-06-11 23:12:07 +020017475 availability). Another possible use which is more of a hack consists in
17476 using dummy servers as boolean variables that can be enabled or disabled from
17477 the CLI, so that rules depending on those ACLs can be tweaked in realtime.
17478
Willy Tarreauff2b7af2017-10-13 11:46:26 +020017479srv_queue([<backend>/]<server>) : integer
17480 Returns an integer value corresponding to the number of connections currently
17481 pending in the designated server's queue. If <backend> is omitted, then the
17482 server is looked up in the current backend. It can sometimes be used together
17483 with the "use-server" directive to force to use a known faster server when it
17484 is not much loaded. See also the "srv_conn", "avg_queue" and "queue" sample
17485 fetch methods.
17486
Willy Tarreau74ca5042013-06-11 23:12:07 +020017487srv_sess_rate([<backend>/]<server>) : integer
17488 Returns an integer corresponding to the sessions creation rate on the
17489 designated server, in number of new sessions per second. If <backend> is
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030017490 omitted, then the server is looked up in the current backend. This is mostly
Willy Tarreau74ca5042013-06-11 23:12:07 +020017491 used with ACLs but can make sense with logs too. This is used to switch to an
17492 alternate backend when an expensive or fragile one reaches too high a session
Davor Ocelice9ed2812017-12-25 17:49:28 +010017493 rate, or to limit abuse of service (e.g. prevent latent requests from
Willy Tarreau74ca5042013-06-11 23:12:07 +020017494 overloading servers).
17495
17496 Example :
17497 # Redirect to a separate back
17498 acl srv1_full srv_sess_rate(be1/srv1) gt 50
17499 acl srv2_full srv_sess_rate(be1/srv2) gt 50
17500 use_backend be2 if srv1_full or srv2_full
17501
Alexbf1bd5a2021-04-24 13:02:21 +020017502srv_iweight([<backend>/]<server>) : integer
Christopher Faulet1bea8652020-07-10 16:03:45 +020017503 Returns an integer corresponding to the server's initial weight. If <backend>
17504 is omitted, then the server is looked up in the current backend. See also
17505 "srv_weight" and "srv_uweight".
17506
Alexbf1bd5a2021-04-24 13:02:21 +020017507srv_uweight([<backend>/]<server>) : integer
Christopher Faulet1bea8652020-07-10 16:03:45 +020017508 Returns an integer corresponding to the user visible server's weight. If
17509 <backend> is omitted, then the server is looked up in the current
17510 backend. See also "srv_weight" and "srv_iweight".
17511
Alexbf1bd5a2021-04-24 13:02:21 +020017512srv_weight([<backend>/]<server>) : integer
Christopher Faulet1bea8652020-07-10 16:03:45 +020017513 Returns an integer corresponding to the current (or effective) server's
17514 weight. If <backend> is omitted, then the server is looked up in the current
17515 backend. See also "srv_iweight" and "srv_uweight".
17516
Willy Tarreau0f30d262014-11-24 16:02:05 +010017517stopping : boolean
17518 Returns TRUE if the process calling the function is currently stopping. This
17519 can be useful for logging, or for relaxing certain checks or helping close
17520 certain connections upon graceful shutdown.
17521
Thierry FOURNIERcc103292015-06-06 19:30:17 +020017522str(<string>) : string
17523 Returns a string.
17524
Willy Tarreau74ca5042013-06-11 23:12:07 +020017525table_avl([<table>]) : integer
17526 Returns the total number of available entries in the current proxy's
17527 stick-table or in the designated stick-table. See also table_cnt.
17528
17529table_cnt([<table>]) : integer
17530 Returns the total number of entries currently in use in the current proxy's
17531 stick-table or in the designated stick-table. See also src_conn_cnt and
17532 table_avl for other entry counting methods.
17533
Christopher Faulet34adb2a2017-11-21 21:45:38 +010017534thread : integer
17535 Returns an integer value corresponding to the position of the thread calling
17536 the function, between 0 and (global.nbthread-1). This is useful for logging
17537 and debugging purposes.
17538
Alexandar Lazica429ad32021-06-01 00:27:01 +020017539uuid([<version>]) : string
17540 Returns a UUID following the RFC4122 standard. If the version is not
17541 specified, a UUID version 4 (fully random) is returned.
17542 Currently, only version 4 is supported.
17543
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020017544var(<var-name>) : undefined
17545 Returns a variable with the stored type. If the variable is not set, the
Daniel Schneller0b547052016-03-21 20:46:57 +010017546 sample fetch fails. The name of the variable starts with an indication
17547 about its scope. The scopes allowed are:
Christopher Fauletff2613e2016-11-09 11:36:17 +010017548 "proc" : the variable is shared with the whole process
Daniel Schneller0b547052016-03-21 20:46:57 +010017549 "sess" : the variable is shared with the whole session
17550 "txn" : the variable is shared with the transaction (request and
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020017551 response),
Daniel Schneller0b547052016-03-21 20:46:57 +010017552 "req" : the variable is shared only during request processing,
17553 "res" : the variable is shared only during response processing.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020017554 This prefix is followed by a name. The separator is a '.'. The name may only
Christopher Fauletb71557a2016-10-31 10:49:03 +010017555 contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
Thierry FOURNIER4834bc72015-06-06 19:29:07 +020017556
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200175577.3.3. Fetching samples at Layer 4
Willy Tarreau74ca5042013-06-11 23:12:07 +020017558----------------------------------
17559
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017560The layer 4 usually describes just the transport layer which in HAProxy is
Willy Tarreau74ca5042013-06-11 23:12:07 +020017561closest to the connection, where no content is yet made available. The fetch
17562methods described here are usable as low as the "tcp-request connection" rule
17563sets unless they require some future information. Those generally include
17564TCP/IP addresses and ports, as well as elements from stick-tables related to
Willy Tarreau4d4149c2013-07-23 19:33:46 +020017565the incoming connection. For retrieving a value from a sticky counters, the
17566counter number can be explicitly set as 0, 1, or 2 using the pre-defined
Moemen MHEDHBI9cf46342018-09-25 17:50:53 +020017567"sc0_", "sc1_", or "sc2_" prefix. These three pre-defined prefixes can only be
17568used if MAX_SESS_STKCTR value does not exceed 3, otherwise the counter number
17569can be specified as the first integer argument when using the "sc_" prefix.
17570Starting from "sc_0" to "sc_N" where N is (MAX_SESS_STKCTR-1). An optional
17571table may be specified with the "sc*" form, in which case the currently
17572tracked key will be looked up into this alternate table instead of the table
17573currently being tracked.
Willy Tarreau74ca5042013-06-11 23:12:07 +020017574
Christopher Faulet7d081f02021-04-15 09:38:37 +020017575bc_dst : ip
17576 This is the destination ip address of the connection on the server side,
17577 which is the server address HAProxy connected to. It is of type IP and works
17578 on both IPv4 and IPv6 tables. On IPv6 tables, IPv4 address is mapped to its
17579 IPv6 equivalent, according to RFC 4291.
17580
17581bc_dst_port : integer
17582 Returns an integer value corresponding to the destination TCP port of the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017583 connection on the server side, which is the port HAProxy connected to.
Christopher Faulet7d081f02021-04-15 09:38:37 +020017584
Jérôme Magnin35e53a62019-01-16 14:38:37 +010017585bc_http_major : integer
Jérôme Magnin86577422018-12-07 09:03:11 +010017586 Returns the backend connection's HTTP major version encoding, which may be 1
17587 for HTTP/0.9 to HTTP/1.1 or 2 for HTTP/2. Note, this is based on the on-wire
17588 encoding and not the version present in the request header.
17589
Christopher Faulet7d081f02021-04-15 09:38:37 +020017590bc_src : ip
17591 This is the source ip address of the connection on the server side, which is
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017592 the server address HAProxy connected from. It is of type IP and works on both
Christopher Faulet7d081f02021-04-15 09:38:37 +020017593 IPv4 and IPv6 tables. On IPv6 tables, IPv4 addresses are mapped to their IPv6
17594 equivalent, according to RFC 4291.
17595
17596bc_src_port : integer
17597 Returns an integer value corresponding to the TCP source port of the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040017598 connection on the server side, which is the port HAProxy connected from.
Christopher Faulet7d081f02021-04-15 09:38:37 +020017599
Willy Tarreau74ca5042013-06-11 23:12:07 +020017600be_id : integer
17601 Returns an integer containing the current backend's id. It can be used in
Christopher Fauletd1b44642020-04-30 09:51:15 +020017602 frontends with responses to check which backend processed the request. It can
17603 also be used in a tcp-check or an http-check ruleset.
Willy Tarreau74ca5042013-06-11 23:12:07 +020017604
Marcin Deranekd2471c22016-12-12 14:08:05 +010017605be_name : string
17606 Returns a string containing the current backend's name. It can be used in
Christopher Fauletd1b44642020-04-30 09:51:15 +020017607 frontends with responses to check which backend processed the request. It can
17608 also be used in a tcp-check or an http-check ruleset.
Marcin Deranekd2471c22016-12-12 14:08:05 +010017609
Amaury Denoyelled91d7792020-12-10 13:43:56 +010017610be_server_timeout : integer
17611 Returns the configuration value in millisecond for the server timeout of the
17612 current backend. This timeout can be overwritten by a "set-timeout" rule. See
17613 also the "cur_server_timeout".
17614
17615be_tunnel_timeout : integer
17616 Returns the configuration value in millisecond for the tunnel timeout of the
17617 current backend. This timeout can be overwritten by a "set-timeout" rule. See
17618 also the "cur_tunnel_timeout".
17619
Amaury Denoyellef7719a22020-12-10 13:43:58 +010017620cur_server_timeout : integer
17621 Returns the currently applied server timeout in millisecond for the stream.
17622 In the default case, this will be equal to be_server_timeout unless a
17623 "set-timeout" rule has been applied. See also "be_server_timeout".
17624
17625cur_tunnel_timeout : integer
17626 Returns the currently applied tunnel timeout in millisecond for the stream.
17627 In the default case, this will be equal to be_tunnel_timeout unless a
17628 "set-timeout" rule has been applied. See also "be_tunnel_timeout".
17629
Willy Tarreau74ca5042013-06-11 23:12:07 +020017630dst : ip
17631 This is the destination IPv4 address of the connection on the client side,
17632 which is the address the client connected to. It can be useful when running
17633 in transparent mode. It is of type IP and works on both IPv4 and IPv6 tables.
17634 On IPv6 tables, IPv4 address is mapped to its IPv6 equivalent, according to
Willy Tarreau64ded3d2019-01-23 10:02:15 +010017635 RFC 4291. When the incoming connection passed through address translation or
17636 redirection involving connection tracking, the original destination address
17637 before the redirection will be reported. On Linux systems, the source and
17638 destination may seldom appear reversed if the nf_conntrack_tcp_loose sysctl
17639 is set, because a late response may reopen a timed out connection and switch
17640 what is believed to be the source and the destination.
Willy Tarreau74ca5042013-06-11 23:12:07 +020017641
17642dst_conn : integer
17643 Returns an integer value corresponding to the number of currently established
17644 connections on the same socket including the one being evaluated. It is
17645 normally used with ACLs but can as well be used to pass the information to
17646 servers in an HTTP header or in logs. It can be used to either return a sorry
17647 page before hard-blocking, or to use a specific backend to drain new requests
17648 when the socket is considered saturated. This offers the ability to assign
17649 different limits to different listening ports or addresses. See also the
17650 "fe_conn" and "be_conn" fetches.
Willy Tarreaud63335a2010-02-26 12:56:52 +010017651
Willy Tarreau16e01562016-08-09 16:46:18 +020017652dst_is_local : boolean
17653 Returns true if the destination address of the incoming connection is local
17654 to the system, or false if the address doesn't exist on the system, meaning
17655 that it was intercepted in transparent mode. It can be useful to apply
17656 certain rules by default to forwarded traffic and other rules to the traffic
Davor Ocelice9ed2812017-12-25 17:49:28 +010017657 targeting the real address of the machine. For example the stats page could
Willy Tarreau16e01562016-08-09 16:46:18 +020017658 be delivered only on this address, or SSH access could be locally redirected.
17659 Please note that the check involves a few system calls, so it's better to do
17660 it only once per connection.
17661
Willy Tarreau74ca5042013-06-11 23:12:07 +020017662dst_port : integer
17663 Returns an integer value corresponding to the destination TCP port of the
17664 connection on the client side, which is the port the client connected to.
17665 This might be used when running in transparent mode, when assigning dynamic
17666 ports to some clients for a whole application session, to stick all users to
17667 a same server, or to pass the destination port information to a server using
17668 an HTTP header.
17669
Willy Tarreau60ca10a2017-08-18 15:26:54 +020017670fc_http_major : integer
17671 Reports the front connection's HTTP major version encoding, which may be 1
17672 for HTTP/0.9 to HTTP/1.1 or 2 for HTTP/2. Note, this is based on the on-wire
17673 encoding and not on the version present in the request header.
17674
Geoff Simmons7185b782019-08-27 18:31:16 +020017675fc_pp_authority : string
17676 Returns the authority TLV sent by the client in the PROXY protocol header,
17677 if any.
17678
Tim Duesterhusd1b15b62020-03-13 12:34:23 +010017679fc_pp_unique_id : string
17680 Returns the unique ID TLV sent by the client in the PROXY protocol header,
17681 if any.
17682
Emeric Brun4f603012017-01-05 15:11:44 +010017683fc_rcvd_proxy : boolean
17684 Returns true if the client initiated the connection with a PROXY protocol
17685 header.
17686
Thierry Fournier / OZON.IO6310bef2016-07-24 20:16:50 +020017687fc_rtt(<unit>) : integer
17688 Returns the Round Trip Time (RTT) measured by the kernel for the client
17689 connection. <unit> is facultative, by default the unit is milliseconds. <unit>
17690 can be set to "ms" for milliseconds or "us" for microseconds. If the server
17691 connection is not established, if the connection is not TCP or if the
17692 operating system does not support TCP_INFO, for example Linux kernels before
17693 2.4, the sample fetch fails.
17694
17695fc_rttvar(<unit>) : integer
17696 Returns the Round Trip Time (RTT) variance measured by the kernel for the
17697 client connection. <unit> is facultative, by default the unit is milliseconds.
17698 <unit> can be set to "ms" for milliseconds or "us" for microseconds. If the
17699 server connection is not established, if the connection is not TCP or if the
17700 operating system does not support TCP_INFO, for example Linux kernels before
17701 2.4, the sample fetch fails.
17702
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017703fc_unacked : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017704 Returns the unacked counter measured by the kernel for the client connection.
17705 If the server connection is not established, if the connection is not TCP or
17706 if the operating system does not support TCP_INFO, for example Linux kernels
17707 before 2.4, the sample fetch fails.
17708
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017709fc_sacked : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017710 Returns the sacked counter measured by the kernel for the client connection.
17711 If the server connection is not established, if the connection is not TCP or
17712 if the operating system does not support TCP_INFO, for example Linux kernels
17713 before 2.4, the sample fetch fails.
17714
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017715fc_retrans : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017716 Returns the retransmits counter measured by the kernel for the client
17717 connection. If the server connection is not established, if the connection is
17718 not TCP or if the operating system does not support TCP_INFO, for example
17719 Linux kernels before 2.4, the sample fetch fails.
17720
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017721fc_fackets : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017722 Returns the fack counter measured by the kernel for the client
17723 connection. If the server connection is not established, if the connection is
17724 not TCP or if the operating system does not support TCP_INFO, for example
17725 Linux kernels before 2.4, the sample fetch fails.
17726
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017727fc_lost : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017728 Returns the lost counter measured by the kernel for the client
17729 connection. If the server connection is not established, if the connection is
17730 not TCP or if the operating system does not support TCP_INFO, for example
17731 Linux kernels before 2.4, the sample fetch fails.
17732
Christopher Fauletba0c53e2019-10-17 14:40:48 +020017733fc_reordering : integer
Joe Williams30fcd392016-08-10 07:06:44 -070017734 Returns the reordering counter measured by the kernel for the client
17735 connection. If the server connection is not established, if the connection is
17736 not TCP or if the operating system does not support TCP_INFO, for example
17737 Linux kernels before 2.4, the sample fetch fails.
17738
Marcin Deranek9a66dfb2018-04-13 14:37:50 +020017739fe_defbe : string
17740 Returns a string containing the frontend's default backend name. It can be
17741 used in frontends to check which backend will handle requests by default.
17742
Willy Tarreau74ca5042013-06-11 23:12:07 +020017743fe_id : integer
17744 Returns an integer containing the current frontend's id. It can be used in
Marcin Deranek6e413ed2016-12-13 12:40:01 +010017745 backends to check from which frontend it was called, or to stick all users
Willy Tarreau74ca5042013-06-11 23:12:07 +020017746 coming via a same frontend to the same server.
17747
Marcin Deranekd2471c22016-12-12 14:08:05 +010017748fe_name : string
17749 Returns a string containing the current frontend's name. It can be used in
17750 backends to check from which frontend it was called, or to stick all users
17751 coming via a same frontend to the same server.
17752
Amaury Denoyelleda184d52020-12-10 13:43:55 +010017753fe_client_timeout : integer
17754 Returns the configuration value in millisecond for the client timeout of the
17755 current frontend.
17756
Cyril Bonté62ba8702014-04-22 23:52:25 +020017757sc_bytes_in_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017758sc0_bytes_in_rate([<table>]) : integer
17759sc1_bytes_in_rate([<table>]) : integer
17760sc2_bytes_in_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017761 Returns the average client-to-server bytes rate from the currently tracked
17762 counters, measured in amount of bytes over the period configured in the
17763 table. See also src_bytes_in_rate.
17764
Cyril Bonté62ba8702014-04-22 23:52:25 +020017765sc_bytes_out_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017766sc0_bytes_out_rate([<table>]) : integer
17767sc1_bytes_out_rate([<table>]) : integer
17768sc2_bytes_out_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017769 Returns the average server-to-client bytes rate from the currently tracked
17770 counters, measured in amount of bytes over the period configured in the
17771 table. See also src_bytes_out_rate.
17772
Cyril Bonté62ba8702014-04-22 23:52:25 +020017773sc_clr_gpc0(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017774sc0_clr_gpc0([<table>]) : integer
17775sc1_clr_gpc0([<table>]) : integer
17776sc2_clr_gpc0([<table>]) : integer
Willy Tarreauf73cd112011-08-13 01:45:16 +020017777 Clears the first General Purpose Counter associated to the currently tracked
17778 counters, and returns its previous value. Before the first invocation, the
Willy Tarreau869948b2013-01-04 14:14:57 +010017779 stored value is zero, so first invocation will always return zero. This is
17780 typically used as a second ACL in an expression in order to mark a connection
17781 when a first ACL was verified :
Willy Tarreauf73cd112011-08-13 01:45:16 +020017782
Jarno Huuskonen676f6222017-03-30 09:19:45 +030017783 Example:
Willy Tarreauf73cd112011-08-13 01:45:16 +020017784 # block if 5 consecutive requests continue to come faster than 10 sess
17785 # per second, and reset the counter as soon as the traffic slows down.
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020017786 acl abuse sc0_http_req_rate gt 10
17787 acl kill sc0_inc_gpc0 gt 5
17788 acl save sc0_clr_gpc0 ge 0
Willy Tarreauf73cd112011-08-13 01:45:16 +020017789 tcp-request connection accept if !abuse save
17790 tcp-request connection reject if abuse kill
17791
Frédéric Lécaille6778b272018-01-29 15:22:53 +010017792sc_clr_gpc1(<ctr>[,<table>]) : integer
17793sc0_clr_gpc1([<table>]) : integer
17794sc1_clr_gpc1([<table>]) : integer
17795sc2_clr_gpc1([<table>]) : integer
17796 Clears the second General Purpose Counter associated to the currently tracked
17797 counters, and returns its previous value. Before the first invocation, the
17798 stored value is zero, so first invocation will always return zero. This is
17799 typically used as a second ACL in an expression in order to mark a connection
17800 when a first ACL was verified.
17801
Cyril Bonté62ba8702014-04-22 23:52:25 +020017802sc_conn_cnt(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017803sc0_conn_cnt([<table>]) : integer
17804sc1_conn_cnt([<table>]) : integer
17805sc2_conn_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010017806 Returns the cumulative number of incoming connections from currently tracked
Willy Tarreaue9656522010-08-17 15:40:09 +020017807 counters. See also src_conn_cnt.
17808
Cyril Bonté62ba8702014-04-22 23:52:25 +020017809sc_conn_cur(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017810sc0_conn_cur([<table>]) : integer
17811sc1_conn_cur([<table>]) : integer
17812sc2_conn_cur([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017813 Returns the current amount of concurrent connections tracking the same
17814 tracked counters. This number is automatically incremented when tracking
17815 begins and decremented when tracking stops. See also src_conn_cur.
17816
Cyril Bonté62ba8702014-04-22 23:52:25 +020017817sc_conn_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017818sc0_conn_rate([<table>]) : integer
17819sc1_conn_rate([<table>]) : integer
17820sc2_conn_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017821 Returns the average connection rate from the currently tracked counters,
17822 measured in amount of connections over the period configured in the table.
17823 See also src_conn_rate.
17824
Cyril Bonté62ba8702014-04-22 23:52:25 +020017825sc_get_gpc0(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017826sc0_get_gpc0([<table>]) : integer
17827sc1_get_gpc0([<table>]) : integer
17828sc2_get_gpc0([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017829 Returns the value of the first General Purpose Counter associated to the
Willy Tarreau4d4149c2013-07-23 19:33:46 +020017830 currently tracked counters. See also src_get_gpc0 and sc/sc0/sc1/sc2_inc_gpc0.
Willy Tarreauba2ffd12013-05-29 15:54:14 +020017831
Frédéric Lécaille6778b272018-01-29 15:22:53 +010017832sc_get_gpc1(<ctr>[,<table>]) : integer
17833sc0_get_gpc1([<table>]) : integer
17834sc1_get_gpc1([<table>]) : integer
17835sc2_get_gpc1([<table>]) : integer
17836 Returns the value of the second General Purpose Counter associated to the
17837 currently tracked counters. See also src_get_gpc1 and sc/sc0/sc1/sc2_inc_gpc1.
17838
Thierry FOURNIER236657b2015-08-19 08:25:14 +020017839sc_get_gpt0(<ctr>[,<table>]) : integer
17840sc0_get_gpt0([<table>]) : integer
17841sc1_get_gpt0([<table>]) : integer
17842sc2_get_gpt0([<table>]) : integer
17843 Returns the value of the first General Purpose Tag associated to the
17844 currently tracked counters. See also src_get_gpt0.
17845
Cyril Bonté62ba8702014-04-22 23:52:25 +020017846sc_gpc0_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017847sc0_gpc0_rate([<table>]) : integer
17848sc1_gpc0_rate([<table>]) : integer
17849sc2_gpc0_rate([<table>]) : integer
Willy Tarreauba2ffd12013-05-29 15:54:14 +020017850 Returns the average increment rate of the first General Purpose Counter
17851 associated to the currently tracked counters. It reports the frequency
17852 which the gpc0 counter was incremented over the configured period. See also
Willy Tarreau4d4149c2013-07-23 19:33:46 +020017853 src_gpc0_rate, sc/sc0/sc1/sc2_get_gpc0, and sc/sc0/sc1/sc2_inc_gpc0. Note
17854 that the "gpc0_rate" counter must be stored in the stick-table for a value to
17855 be returned, as "gpc0" only holds the event count.
Willy Tarreaue9656522010-08-17 15:40:09 +020017856
Frédéric Lécaille6778b272018-01-29 15:22:53 +010017857sc_gpc1_rate(<ctr>[,<table>]) : integer
17858sc0_gpc1_rate([<table>]) : integer
17859sc1_gpc1_rate([<table>]) : integer
17860sc2_gpc1_rate([<table>]) : integer
17861 Returns the average increment rate of the second General Purpose Counter
17862 associated to the currently tracked counters. It reports the frequency
17863 which the gpc1 counter was incremented over the configured period. See also
17864 src_gpcA_rate, sc/sc0/sc1/sc2_get_gpc1, and sc/sc0/sc1/sc2_inc_gpc1. Note
17865 that the "gpc1_rate" counter must be stored in the stick-table for a value to
17866 be returned, as "gpc1" only holds the event count.
17867
Cyril Bonté62ba8702014-04-22 23:52:25 +020017868sc_http_err_cnt(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017869sc0_http_err_cnt([<table>]) : integer
17870sc1_http_err_cnt([<table>]) : integer
17871sc2_http_err_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010017872 Returns the cumulative number of HTTP errors from the currently tracked
Willy Tarreaue9656522010-08-17 15:40:09 +020017873 counters. This includes the both request errors and 4xx error responses.
17874 See also src_http_err_cnt.
17875
Cyril Bonté62ba8702014-04-22 23:52:25 +020017876sc_http_err_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017877sc0_http_err_rate([<table>]) : integer
17878sc1_http_err_rate([<table>]) : integer
17879sc2_http_err_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017880 Returns the average rate of HTTP errors from the currently tracked counters,
17881 measured in amount of errors over the period configured in the table. This
17882 includes the both request errors and 4xx error responses. See also
17883 src_http_err_rate.
17884
Willy Tarreau826f3ab2021-02-10 12:07:15 +010017885sc_http_fail_cnt(<ctr>[,<table>]) : integer
17886sc0_http_fail_cnt([<table>]) : integer
17887sc1_http_fail_cnt([<table>]) : integer
17888sc2_http_fail_cnt([<table>]) : integer
17889 Returns the cumulative number of HTTP response failures from the currently
17890 tracked counters. This includes the both response errors and 5xx status codes
17891 other than 501 and 505. See also src_http_fail_cnt.
17892
17893sc_http_fail_rate(<ctr>[,<table>]) : integer
17894sc0_http_fail_rate([<table>]) : integer
17895sc1_http_fail_rate([<table>]) : integer
17896sc2_http_fail_rate([<table>]) : integer
17897 Returns the average rate of HTTP response failures from the currently tracked
17898 counters, measured in amount of failures over the period configured in the
17899 table. This includes the both response errors and 5xx status codes other than
17900 501 and 505. See also src_http_fail_rate.
17901
Cyril Bonté62ba8702014-04-22 23:52:25 +020017902sc_http_req_cnt(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017903sc0_http_req_cnt([<table>]) : integer
17904sc1_http_req_cnt([<table>]) : integer
17905sc2_http_req_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010017906 Returns the cumulative number of HTTP requests from the currently tracked
Willy Tarreaue9656522010-08-17 15:40:09 +020017907 counters. This includes every started request, valid or not. See also
17908 src_http_req_cnt.
17909
Cyril Bonté62ba8702014-04-22 23:52:25 +020017910sc_http_req_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017911sc0_http_req_rate([<table>]) : integer
17912sc1_http_req_rate([<table>]) : integer
17913sc2_http_req_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017914 Returns the average rate of HTTP requests from the currently tracked
17915 counters, measured in amount of requests over the period configured in
17916 the table. This includes every started request, valid or not. See also
17917 src_http_req_rate.
17918
Cyril Bonté62ba8702014-04-22 23:52:25 +020017919sc_inc_gpc0(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017920sc0_inc_gpc0([<table>]) : integer
17921sc1_inc_gpc0([<table>]) : integer
17922sc2_inc_gpc0([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017923 Increments the first General Purpose Counter associated to the currently
Willy Tarreau869948b2013-01-04 14:14:57 +010017924 tracked counters, and returns its new value. Before the first invocation,
17925 the stored value is zero, so first invocation will increase it to 1 and will
17926 return 1. This is typically used as a second ACL in an expression in order
17927 to mark a connection when a first ACL was verified :
Willy Tarreaue9656522010-08-17 15:40:09 +020017928
Jarno Huuskonen676f6222017-03-30 09:19:45 +030017929 Example:
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020017930 acl abuse sc0_http_req_rate gt 10
17931 acl kill sc0_inc_gpc0 gt 0
Willy Tarreaue9656522010-08-17 15:40:09 +020017932 tcp-request connection reject if abuse kill
17933
Frédéric Lécaille6778b272018-01-29 15:22:53 +010017934sc_inc_gpc1(<ctr>[,<table>]) : integer
17935sc0_inc_gpc1([<table>]) : integer
17936sc1_inc_gpc1([<table>]) : integer
17937sc2_inc_gpc1([<table>]) : integer
17938 Increments the second General Purpose Counter associated to the currently
17939 tracked counters, and returns its new value. Before the first invocation,
17940 the stored value is zero, so first invocation will increase it to 1 and will
17941 return 1. This is typically used as a second ACL in an expression in order
17942 to mark a connection when a first ACL was verified.
17943
Cyril Bonté62ba8702014-04-22 23:52:25 +020017944sc_kbytes_in(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017945sc0_kbytes_in([<table>]) : integer
17946sc1_kbytes_in([<table>]) : integer
17947sc2_kbytes_in([<table>]) : integer
Willy Tarreaua01b9742014-07-10 15:29:24 +020017948 Returns the total amount of client-to-server data from the currently tracked
17949 counters, measured in kilobytes. The test is currently performed on 32-bit
17950 integers, which limits values to 4 terabytes. See also src_kbytes_in.
Willy Tarreaue9656522010-08-17 15:40:09 +020017951
Cyril Bonté62ba8702014-04-22 23:52:25 +020017952sc_kbytes_out(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017953sc0_kbytes_out([<table>]) : integer
17954sc1_kbytes_out([<table>]) : integer
17955sc2_kbytes_out([<table>]) : integer
Willy Tarreaua01b9742014-07-10 15:29:24 +020017956 Returns the total amount of server-to-client data from the currently tracked
17957 counters, measured in kilobytes. The test is currently performed on 32-bit
17958 integers, which limits values to 4 terabytes. See also src_kbytes_out.
Willy Tarreaue9656522010-08-17 15:40:09 +020017959
Cyril Bonté62ba8702014-04-22 23:52:25 +020017960sc_sess_cnt(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017961sc0_sess_cnt([<table>]) : integer
17962sc1_sess_cnt([<table>]) : integer
17963sc2_sess_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010017964 Returns the cumulative number of incoming connections that were transformed
Willy Tarreaue9656522010-08-17 15:40:09 +020017965 into sessions, which means that they were accepted by a "tcp-request
17966 connection" rule, from the currently tracked counters. A backend may count
17967 more sessions than connections because each connection could result in many
Jamie Gloudonaaa21002012-08-25 00:18:33 -040017968 backend sessions if some HTTP keep-alive is performed over the connection
Willy Tarreaue9656522010-08-17 15:40:09 +020017969 with the client. See also src_sess_cnt.
17970
Cyril Bonté62ba8702014-04-22 23:52:25 +020017971sc_sess_rate(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017972sc0_sess_rate([<table>]) : integer
17973sc1_sess_rate([<table>]) : integer
17974sc2_sess_rate([<table>]) : integer
Willy Tarreaue9656522010-08-17 15:40:09 +020017975 Returns the average session rate from the currently tracked counters,
17976 measured in amount of sessions over the period configured in the table. A
17977 session is a connection that got past the early "tcp-request connection"
17978 rules. A backend may count more sessions than connections because each
17979 connection could result in many backend sessions if some HTTP keep-alive is
Jamie Gloudonaaa21002012-08-25 00:18:33 -040017980 performed over the connection with the client. See also src_sess_rate.
Willy Tarreaue9656522010-08-17 15:40:09 +020017981
Cyril Bonté62ba8702014-04-22 23:52:25 +020017982sc_tracked(<ctr>[,<table>]) : boolean
Willy Tarreau0f791d42013-07-23 19:56:43 +020017983sc0_tracked([<table>]) : boolean
17984sc1_tracked([<table>]) : boolean
17985sc2_tracked([<table>]) : boolean
Willy Tarreau6f1615f2013-06-03 15:15:22 +020017986 Returns true if the designated session counter is currently being tracked by
17987 the current session. This can be useful when deciding whether or not we want
17988 to set some values in a header passed to the server.
17989
Cyril Bonté62ba8702014-04-22 23:52:25 +020017990sc_trackers(<ctr>[,<table>]) : integer
Willy Tarreau0f791d42013-07-23 19:56:43 +020017991sc0_trackers([<table>]) : integer
17992sc1_trackers([<table>]) : integer
17993sc2_trackers([<table>]) : integer
Willy Tarreau2406db42012-12-09 12:16:43 +010017994 Returns the current amount of concurrent connections tracking the same
17995 tracked counters. This number is automatically incremented when tracking
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020017996 begins and decremented when tracking stops. It differs from sc0_conn_cur in
Willy Tarreau2406db42012-12-09 12:16:43 +010017997 that it does not rely on any stored information but on the table's reference
17998 count (the "use" value which is returned by "show table" on the CLI). This
Willy Tarreau74ca5042013-06-11 23:12:07 +020017999 may sometimes be more suited for layer7 tracking. It can be used to tell a
18000 server how many concurrent connections there are from a given address for
18001 example.
Willy Tarreau2406db42012-12-09 12:16:43 +010018002
Willy Tarreau74ca5042013-06-11 23:12:07 +020018003so_id : integer
18004 Returns an integer containing the current listening socket's id. It is useful
18005 in frontends involving many "bind" lines, or to stick all users coming via a
18006 same socket to the same server.
Willy Tarreaud63335a2010-02-26 12:56:52 +010018007
Jerome Magnineb421b22020-03-27 22:08:40 +010018008so_name : string
18009 Returns a string containing the current listening socket's name, as defined
18010 with name on a "bind" line. It can serve the same purposes as so_id but with
18011 strings instead of integers.
18012
Willy Tarreau74ca5042013-06-11 23:12:07 +020018013src : ip
Davor Ocelice9ed2812017-12-25 17:49:28 +010018014 This is the source IPv4 address of the client of the session. It is of type
Willy Tarreau74ca5042013-06-11 23:12:07 +020018015 IP and works on both IPv4 and IPv6 tables. On IPv6 tables, IPv4 addresses are
18016 mapped to their IPv6 equivalent, according to RFC 4291. Note that it is the
18017 TCP-level source address which is used, and not the address of a client
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010018018 behind a proxy. However if the "accept-proxy" or "accept-netscaler-cip" bind
18019 directive is used, it can be the address of a client behind another
18020 PROXY-protocol compatible component for all rule sets except
Willy Tarreau64ded3d2019-01-23 10:02:15 +010018021 "tcp-request connection" which sees the real address. When the incoming
18022 connection passed through address translation or redirection involving
18023 connection tracking, the original destination address before the redirection
18024 will be reported. On Linux systems, the source and destination may seldom
18025 appear reversed if the nf_conntrack_tcp_loose sysctl is set, because a late
18026 response may reopen a timed out connection and switch what is believed to be
18027 the source and the destination.
Willy Tarreaud63335a2010-02-26 12:56:52 +010018028
Thierry FOURNIERd5f624d2013-11-26 11:52:33 +010018029 Example:
18030 # add an HTTP header in requests with the originating address' country
18031 http-request set-header X-Country %[src,map_ip(geoip.lst)]
18032
Willy Tarreau74ca5042013-06-11 23:12:07 +020018033src_bytes_in_rate([<table>]) : integer
18034 Returns the average bytes rate from the incoming connection's source address
18035 in the current proxy's stick-table or in the designated stick-table, measured
18036 in amount of bytes over the period configured in the table. If the address is
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018037 not found, zero is returned. See also sc/sc0/sc1/sc2_bytes_in_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018038
Willy Tarreau74ca5042013-06-11 23:12:07 +020018039src_bytes_out_rate([<table>]) : integer
18040 Returns the average bytes rate to the incoming connection's source address in
18041 the current proxy's stick-table or in the designated stick-table, measured in
Willy Tarreauc9705a12010-07-27 20:05:50 +020018042 amount of bytes over the period configured in the table. If the address is
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018043 not found, zero is returned. See also sc/sc0/sc1/sc2_bytes_out_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018044
Willy Tarreau74ca5042013-06-11 23:12:07 +020018045src_clr_gpc0([<table>]) : integer
18046 Clears the first General Purpose Counter associated to the incoming
18047 connection's source address in the current proxy's stick-table or in the
18048 designated stick-table, and returns its previous value. If the address is not
18049 found, an entry is created and 0 is returned. This is typically used as a
18050 second ACL in an expression in order to mark a connection when a first ACL
18051 was verified :
Willy Tarreauf73cd112011-08-13 01:45:16 +020018052
Jarno Huuskonen676f6222017-03-30 09:19:45 +030018053 Example:
Willy Tarreauf73cd112011-08-13 01:45:16 +020018054 # block if 5 consecutive requests continue to come faster than 10 sess
18055 # per second, and reset the counter as soon as the traffic slows down.
18056 acl abuse src_http_req_rate gt 10
18057 acl kill src_inc_gpc0 gt 5
Willy Tarreau869948b2013-01-04 14:14:57 +010018058 acl save src_clr_gpc0 ge 0
Willy Tarreauf73cd112011-08-13 01:45:16 +020018059 tcp-request connection accept if !abuse save
18060 tcp-request connection reject if abuse kill
18061
Frédéric Lécaille6778b272018-01-29 15:22:53 +010018062src_clr_gpc1([<table>]) : integer
18063 Clears the second General Purpose Counter associated to the incoming
18064 connection's source address in the current proxy's stick-table or in the
18065 designated stick-table, and returns its previous value. If the address is not
18066 found, an entry is created and 0 is returned. This is typically used as a
18067 second ACL in an expression in order to mark a connection when a first ACL
18068 was verified.
18069
Willy Tarreau74ca5042013-06-11 23:12:07 +020018070src_conn_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010018071 Returns the cumulative number of connections initiated from the current
Willy Tarreau74ca5042013-06-11 23:12:07 +020018072 incoming connection's source address in the current proxy's stick-table or in
Willy Tarreauc9705a12010-07-27 20:05:50 +020018073 the designated stick-table. If the address is not found, zero is returned.
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018074 See also sc/sc0/sc1/sc2_conn_cnt.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018075
Willy Tarreau74ca5042013-06-11 23:12:07 +020018076src_conn_cur([<table>]) : integer
Willy Tarreauc9705a12010-07-27 20:05:50 +020018077 Returns the current amount of concurrent connections initiated from the
Willy Tarreau74ca5042013-06-11 23:12:07 +020018078 current incoming connection's source address in the current proxy's
18079 stick-table or in the designated stick-table. If the address is not found,
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018080 zero is returned. See also sc/sc0/sc1/sc2_conn_cur.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018081
Willy Tarreau74ca5042013-06-11 23:12:07 +020018082src_conn_rate([<table>]) : integer
18083 Returns the average connection rate from the incoming connection's source
18084 address in the current proxy's stick-table or in the designated stick-table,
18085 measured in amount of connections over the period configured in the table. If
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018086 the address is not found, zero is returned. See also sc/sc0/sc1/sc2_conn_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018087
Willy Tarreau74ca5042013-06-11 23:12:07 +020018088src_get_gpc0([<table>]) : integer
Willy Tarreauc9705a12010-07-27 20:05:50 +020018089 Returns the value of the first General Purpose Counter associated to the
Willy Tarreau74ca5042013-06-11 23:12:07 +020018090 incoming connection's source address in the current proxy's stick-table or in
Willy Tarreauc9705a12010-07-27 20:05:50 +020018091 the designated stick-table. If the address is not found, zero is returned.
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018092 See also sc/sc0/sc1/sc2_get_gpc0 and src_inc_gpc0.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018093
Frédéric Lécaille6778b272018-01-29 15:22:53 +010018094src_get_gpc1([<table>]) : integer
18095 Returns the value of the second General Purpose Counter associated to the
18096 incoming connection's source address in the current proxy's stick-table or in
18097 the designated stick-table. If the address is not found, zero is returned.
18098 See also sc/sc0/sc1/sc2_get_gpc1 and src_inc_gpc1.
18099
Thierry FOURNIER236657b2015-08-19 08:25:14 +020018100src_get_gpt0([<table>]) : integer
18101 Returns the value of the first General Purpose Tag associated to the
18102 incoming connection's source address in the current proxy's stick-table or in
18103 the designated stick-table. If the address is not found, zero is returned.
18104 See also sc/sc0/sc1/sc2_get_gpt0.
18105
Willy Tarreau74ca5042013-06-11 23:12:07 +020018106src_gpc0_rate([<table>]) : integer
Willy Tarreauba2ffd12013-05-29 15:54:14 +020018107 Returns the average increment rate of the first General Purpose Counter
Willy Tarreau74ca5042013-06-11 23:12:07 +020018108 associated to the incoming connection's source address in the current proxy's
Willy Tarreauba2ffd12013-05-29 15:54:14 +020018109 stick-table or in the designated stick-table. It reports the frequency
18110 which the gpc0 counter was incremented over the configured period. See also
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018111 sc/sc0/sc1/sc2_gpc0_rate, src_get_gpc0, and sc/sc0/sc1/sc2_inc_gpc0. Note
18112 that the "gpc0_rate" counter must be stored in the stick-table for a value to
18113 be returned, as "gpc0" only holds the event count.
Willy Tarreauba2ffd12013-05-29 15:54:14 +020018114
Frédéric Lécaille6778b272018-01-29 15:22:53 +010018115src_gpc1_rate([<table>]) : integer
18116 Returns the average increment rate of the second General Purpose Counter
18117 associated to the incoming connection's source address in the current proxy's
18118 stick-table or in the designated stick-table. It reports the frequency
18119 which the gpc1 counter was incremented over the configured period. See also
18120 sc/sc0/sc1/sc2_gpc1_rate, src_get_gpc1, and sc/sc0/sc1/sc2_inc_gpc1. Note
18121 that the "gpc1_rate" counter must be stored in the stick-table for a value to
18122 be returned, as "gpc1" only holds the event count.
18123
Willy Tarreau74ca5042013-06-11 23:12:07 +020018124src_http_err_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010018125 Returns the cumulative number of HTTP errors from the incoming connection's
Willy Tarreau74ca5042013-06-11 23:12:07 +020018126 source address in the current proxy's stick-table or in the designated
Willy Tarreauc9705a12010-07-27 20:05:50 +020018127 stick-table. This includes the both request errors and 4xx error responses.
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018128 See also sc/sc0/sc1/sc2_http_err_cnt. If the address is not found, zero is
Willy Tarreau74ca5042013-06-11 23:12:07 +020018129 returned.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018130
Willy Tarreau74ca5042013-06-11 23:12:07 +020018131src_http_err_rate([<table>]) : integer
18132 Returns the average rate of HTTP errors from the incoming connection's source
18133 address in the current proxy's stick-table or in the designated stick-table,
18134 measured in amount of errors over the period configured in the table. This
18135 includes the both request errors and 4xx error responses. If the address is
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018136 not found, zero is returned. See also sc/sc0/sc1/sc2_http_err_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018137
Willy Tarreau826f3ab2021-02-10 12:07:15 +010018138src_http_fail_cnt([<table>]) : integer
18139 Returns the cumulative number of HTTP response failures triggered by the
18140 incoming connection's source address in the current proxy's stick-table or in
Ilya Shipitsin0de36ad2021-02-20 00:23:36 +050018141 the designated stick-table. This includes the both response errors and 5xx
Willy Tarreau826f3ab2021-02-10 12:07:15 +010018142 status codes other than 501 and 505. See also sc/sc0/sc1/sc2_http_fail_cnt.
18143 If the address is not found, zero is returned.
18144
18145src_http_fail_rate([<table>]) : integer
18146 Returns the average rate of HTTP response failures triggered by the incoming
18147 connection's source address in the current proxy's stick-table or in the
18148 designated stick-table, measured in amount of failures over the period
18149 configured in the table. This includes the both response errors and 5xx
18150 status codes other than 501 and 505. If the address is not found, zero is
18151 returned. See also sc/sc0/sc1/sc2_http_fail_rate.
18152
Willy Tarreau74ca5042013-06-11 23:12:07 +020018153src_http_req_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010018154 Returns the cumulative number of HTTP requests from the incoming connection's
Willy Tarreau74ca5042013-06-11 23:12:07 +020018155 source address in the current proxy's stick-table or in the designated stick-
18156 table. This includes every started request, valid or not. If the address is
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018157 not found, zero is returned. See also sc/sc0/sc1/sc2_http_req_cnt.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018158
Willy Tarreau74ca5042013-06-11 23:12:07 +020018159src_http_req_rate([<table>]) : integer
18160 Returns the average rate of HTTP requests from the incoming connection's
18161 source address in the current proxy's stick-table or in the designated stick-
18162 table, measured in amount of requests over the period configured in the
Willy Tarreauc9705a12010-07-27 20:05:50 +020018163 table. This includes every started request, valid or not. If the address is
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018164 not found, zero is returned. See also sc/sc0/sc1/sc2_http_req_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018165
Willy Tarreau74ca5042013-06-11 23:12:07 +020018166src_inc_gpc0([<table>]) : integer
18167 Increments the first General Purpose Counter associated to the incoming
18168 connection's source address in the current proxy's stick-table or in the
18169 designated stick-table, and returns its new value. If the address is not
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020018170 found, an entry is created and 1 is returned. See also sc0/sc2/sc2_inc_gpc0.
Willy Tarreau74ca5042013-06-11 23:12:07 +020018171 This is typically used as a second ACL in an expression in order to mark a
18172 connection when a first ACL was verified :
Willy Tarreauc9705a12010-07-27 20:05:50 +020018173
Jarno Huuskonen676f6222017-03-30 09:19:45 +030018174 Example:
Willy Tarreauc9705a12010-07-27 20:05:50 +020018175 acl abuse src_http_req_rate gt 10
Willy Tarreau869948b2013-01-04 14:14:57 +010018176 acl kill src_inc_gpc0 gt 0
Willy Tarreaue9656522010-08-17 15:40:09 +020018177 tcp-request connection reject if abuse kill
Willy Tarreauc9705a12010-07-27 20:05:50 +020018178
Frédéric Lécaille6778b272018-01-29 15:22:53 +010018179src_inc_gpc1([<table>]) : integer
18180 Increments the second General Purpose Counter associated to the incoming
18181 connection's source address in the current proxy's stick-table or in the
18182 designated stick-table, and returns its new value. If the address is not
18183 found, an entry is created and 1 is returned. See also sc0/sc2/sc2_inc_gpc1.
18184 This is typically used as a second ACL in an expression in order to mark a
18185 connection when a first ACL was verified.
18186
Willy Tarreau16e01562016-08-09 16:46:18 +020018187src_is_local : boolean
18188 Returns true if the source address of the incoming connection is local to the
18189 system, or false if the address doesn't exist on the system, meaning that it
18190 comes from a remote machine. Note that UNIX addresses are considered local.
18191 It can be useful to apply certain access restrictions based on where the
Davor Ocelice9ed2812017-12-25 17:49:28 +010018192 client comes from (e.g. require auth or https for remote machines). Please
Willy Tarreau16e01562016-08-09 16:46:18 +020018193 note that the check involves a few system calls, so it's better to do it only
18194 once per connection.
18195
Willy Tarreau74ca5042013-06-11 23:12:07 +020018196src_kbytes_in([<table>]) : integer
Willy Tarreaua01b9742014-07-10 15:29:24 +020018197 Returns the total amount of data received from the incoming connection's
18198 source address in the current proxy's stick-table or in the designated
18199 stick-table, measured in kilobytes. If the address is not found, zero is
18200 returned. The test is currently performed on 32-bit integers, which limits
18201 values to 4 terabytes. See also sc/sc0/sc1/sc2_kbytes_in.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018202
Willy Tarreau74ca5042013-06-11 23:12:07 +020018203src_kbytes_out([<table>]) : integer
Willy Tarreaua01b9742014-07-10 15:29:24 +020018204 Returns the total amount of data sent to the incoming connection's source
18205 address in the current proxy's stick-table or in the designated stick-table,
18206 measured in kilobytes. If the address is not found, zero is returned. The
18207 test is currently performed on 32-bit integers, which limits values to 4
18208 terabytes. See also sc/sc0/sc1/sc2_kbytes_out.
Willy Tarreaua975b8f2010-06-05 19:13:27 +020018209
Willy Tarreau74ca5042013-06-11 23:12:07 +020018210src_port : integer
18211 Returns an integer value corresponding to the TCP source port of the
18212 connection on the client side, which is the port the client connected from.
18213 Usage of this function is very limited as modern protocols do not care much
18214 about source ports nowadays.
Willy Tarreau079ff0a2009-03-05 21:34:28 +010018215
Willy Tarreau74ca5042013-06-11 23:12:07 +020018216src_sess_cnt([<table>]) : integer
Davor Ocelice9ed2812017-12-25 17:49:28 +010018217 Returns the cumulative number of connections initiated from the incoming
Willy Tarreauc9705a12010-07-27 20:05:50 +020018218 connection's source IPv4 address in the current proxy's stick-table or in the
18219 designated stick-table, that were transformed into sessions, which means that
18220 they were accepted by "tcp-request" rules. If the address is not found, zero
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018221 is returned. See also sc/sc0/sc1/sc2_sess_cnt.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018222
Willy Tarreau74ca5042013-06-11 23:12:07 +020018223src_sess_rate([<table>]) : integer
18224 Returns the average session rate from the incoming connection's source
18225 address in the current proxy's stick-table or in the designated stick-table,
18226 measured in amount of sessions over the period configured in the table. A
18227 session is a connection that went past the early "tcp-request" rules. If the
Willy Tarreau4d4149c2013-07-23 19:33:46 +020018228 address is not found, zero is returned. See also sc/sc0/sc1/sc2_sess_rate.
Willy Tarreauc9705a12010-07-27 20:05:50 +020018229
Willy Tarreau74ca5042013-06-11 23:12:07 +020018230src_updt_conn_cnt([<table>]) : integer
18231 Creates or updates the entry associated to the incoming connection's source
18232 address in the current proxy's stick-table or in the designated stick-table.
18233 This table must be configured to store the "conn_cnt" data type, otherwise
18234 the match will be ignored. The current count is incremented by one, and the
18235 expiration timer refreshed. The updated count is returned, so this match
18236 can't return zero. This was used to reject service abusers based on their
18237 source address. Note: it is recommended to use the more complete "track-sc*"
18238 actions in "tcp-request" rules instead.
Willy Tarreaua975b8f2010-06-05 19:13:27 +020018239
18240 Example :
18241 # This frontend limits incoming SSH connections to 3 per 10 second for
18242 # each source address, and rejects excess connections until a 10 second
18243 # silence is observed. At most 20 addresses are tracked.
18244 listen ssh
18245 bind :22
18246 mode tcp
18247 maxconn 100
Willy Tarreauc9705a12010-07-27 20:05:50 +020018248 stick-table type ip size 20 expire 10s store conn_cnt
Willy Tarreau74ca5042013-06-11 23:12:07 +020018249 tcp-request content reject if { src_updt_conn_cnt gt 3 }
Willy Tarreaua975b8f2010-06-05 19:13:27 +020018250 server local 127.0.0.1:22
18251
Willy Tarreau74ca5042013-06-11 23:12:07 +020018252srv_id : integer
18253 Returns an integer containing the server's id when processing the response.
18254 While it's almost only used with ACLs, it may be used for logging or
Christopher Fauletd1b44642020-04-30 09:51:15 +020018255 debugging. It can also be used in a tcp-check or an http-check ruleset.
Hervé COMMOWICKdaa824e2011-08-05 12:09:44 +020018256
vkill1dfd1652019-10-30 16:58:14 +080018257srv_name : string
18258 Returns a string containing the server's name when processing the response.
18259 While it's almost only used with ACLs, it may be used for logging or
Christopher Fauletd1b44642020-04-30 09:51:15 +020018260 debugging. It can also be used in a tcp-check or an http-check ruleset.
vkill1dfd1652019-10-30 16:58:14 +080018261
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200182627.3.4. Fetching samples at Layer 5
Willy Tarreau74ca5042013-06-11 23:12:07 +020018263----------------------------------
Willy Tarreau0b1cd942010-05-16 22:18:27 +020018264
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018265The layer 5 usually describes just the session layer which in HAProxy is
Willy Tarreau74ca5042013-06-11 23:12:07 +020018266closest to the session once all the connection handshakes are finished, but
18267when no content is yet made available. The fetch methods described here are
18268usable as low as the "tcp-request content" rule sets unless they require some
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030018269future information. Those generally include the results of SSL negotiations.
Willy Tarreauc735a072011-03-29 00:57:02 +020018270
Ben Shillitof25e8e52016-12-02 14:25:37 +00001827151d.all(<prop>[,<prop>*]) : string
18272 Returns values for the properties requested as a string, where values are
18273 separated by the delimiter specified with "51degrees-property-separator".
18274 The device is identified using all the important HTTP headers from the
18275 request. The function can be passed up to five property names, and if a
18276 property name can't be found, the value "NoData" is returned.
18277
18278 Example :
18279 # Here the header "X-51D-DeviceTypeMobileTablet" is added to the request
18280 # containing the three properties requested using all relevant headers from
18281 # the request.
18282 frontend http-in
18283 bind *:8081
18284 default_backend servers
18285 http-request set-header X-51D-DeviceTypeMobileTablet \
18286 %[51d.all(DeviceType,IsMobile,IsTablet)]
18287
Emeric Brun645ae792014-04-30 14:21:06 +020018288ssl_bc : boolean
18289 Returns true when the back connection was made via an SSL/TLS transport
18290 layer and is locally deciphered. This means the outgoing connection was made
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018291 other a server with the "ssl" option. It can be used in a tcp-check or an
18292 http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018293
18294ssl_bc_alg_keysize : integer
18295 Returns the symmetric cipher key size supported in bits when the outgoing
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018296 connection was made over an SSL/TLS transport layer. It can be used in a
18297 tcp-check or an http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018298
Olivier Houchard6b77f492018-11-22 18:18:29 +010018299ssl_bc_alpn : string
18300 This extracts the Application Layer Protocol Negotiation field from an
18301 outgoing connection made via a TLS transport layer.
Michael Prokop4438c602019-05-24 10:25:45 +020018302 The result is a string containing the protocol name negotiated with the
Olivier Houchard6b77f492018-11-22 18:18:29 +010018303 server. The SSL library must have been built with support for TLS
18304 extensions enabled (check haproxy -vv). Note that the TLS ALPN extension is
18305 not advertised unless the "alpn" keyword on the "server" line specifies a
18306 protocol list. Also, nothing forces the server to pick a protocol from this
18307 list, any other one may be requested. The TLS ALPN extension is meant to
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018308 replace the TLS NPN extension. See also "ssl_bc_npn". It can be used in a
18309 tcp-check or an http-check ruleset.
Olivier Houchard6b77f492018-11-22 18:18:29 +010018310
Emeric Brun645ae792014-04-30 14:21:06 +020018311ssl_bc_cipher : string
18312 Returns the name of the used cipher when the outgoing connection was made
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018313 over an SSL/TLS transport layer. It can be used in a tcp-check or an
18314 http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018315
Patrick Hemmer65674662019-06-04 08:13:03 -040018316ssl_bc_client_random : binary
18317 Returns the client random of the back connection when the incoming connection
18318 was made over an SSL/TLS transport layer. It is useful to to decrypt traffic
18319 sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or BoringSSL.
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018320 It can be used in a tcp-check or an http-check ruleset.
Patrick Hemmer65674662019-06-04 08:13:03 -040018321
Emeric Brun74f7ffa2018-02-19 16:14:12 +010018322ssl_bc_is_resumed : boolean
18323 Returns true when the back connection was made over an SSL/TLS transport
18324 layer and the newly created SSL session was resumed using a cached
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018325 session or a TLS ticket. It can be used in a tcp-check or an http-check
18326 ruleset.
Emeric Brun74f7ffa2018-02-19 16:14:12 +010018327
Olivier Houchard6b77f492018-11-22 18:18:29 +010018328ssl_bc_npn : string
18329 This extracts the Next Protocol Negotiation field from an outgoing connection
18330 made via a TLS transport layer. The result is a string containing the
Michael Prokop4438c602019-05-24 10:25:45 +020018331 protocol name negotiated with the server . The SSL library must have been
Olivier Houchard6b77f492018-11-22 18:18:29 +010018332 built with support for TLS extensions enabled (check haproxy -vv). Note that
18333 the TLS NPN extension is not advertised unless the "npn" keyword on the
18334 "server" line specifies a protocol list. Also, nothing forces the server to
18335 pick a protocol from this list, any other one may be used. Please note that
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018336 the TLS NPN extension was replaced with ALPN. It can be used in a tcp-check
18337 or an http-check ruleset.
Olivier Houchard6b77f492018-11-22 18:18:29 +010018338
Emeric Brun645ae792014-04-30 14:21:06 +020018339ssl_bc_protocol : string
18340 Returns the name of the used protocol when the outgoing connection was made
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018341 over an SSL/TLS transport layer. It can be used in a tcp-check or an
18342 http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018343
Emeric Brunb73a9b02014-04-30 18:49:19 +020018344ssl_bc_unique_id : binary
Emeric Brun645ae792014-04-30 14:21:06 +020018345 When the outgoing connection was made over an SSL/TLS transport layer,
Emeric Brunb73a9b02014-04-30 18:49:19 +020018346 returns the TLS unique ID as defined in RFC5929 section 3. The unique id
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018347 can be encoded to base64 using the converter: "ssl_bc_unique_id,base64". It
18348 can be used in a tcp-check or an http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018349
Patrick Hemmer65674662019-06-04 08:13:03 -040018350ssl_bc_server_random : binary
18351 Returns the server random of the back connection when the incoming connection
18352 was made over an SSL/TLS transport layer. It is useful to to decrypt traffic
18353 sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or BoringSSL.
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018354 It can be used in a tcp-check or an http-check ruleset.
Patrick Hemmer65674662019-06-04 08:13:03 -040018355
Emeric Brun645ae792014-04-30 14:21:06 +020018356ssl_bc_session_id : binary
18357 Returns the SSL ID of the back connection when the outgoing connection was
18358 made over an SSL/TLS transport layer. It is useful to log if we want to know
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018359 if session was reused or not. It can be used in a tcp-check or an http-check
18360 ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018361
Patrick Hemmere0275472018-04-28 19:15:51 -040018362ssl_bc_session_key : binary
18363 Returns the SSL session master key of the back connection when the outgoing
18364 connection was made over an SSL/TLS transport layer. It is useful to decrypt
18365 traffic sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018366 BoringSSL. It can be used in a tcp-check or an http-check ruleset.
Patrick Hemmere0275472018-04-28 19:15:51 -040018367
Emeric Brun645ae792014-04-30 14:21:06 +020018368ssl_bc_use_keysize : integer
18369 Returns the symmetric cipher key size used in bits when the outgoing
Christopher Fauletd92ea7f2020-04-30 10:03:55 +020018370 connection was made over an SSL/TLS transport layer. It can be used in a
18371 tcp-check or an http-check ruleset.
Emeric Brun645ae792014-04-30 14:21:06 +020018372
Willy Tarreau74ca5042013-06-11 23:12:07 +020018373ssl_c_ca_err : integer
18374 When the incoming connection was made over an SSL/TLS transport layer,
18375 returns the ID of the first error detected during verification of the client
18376 certificate at depth > 0, or 0 if no error was encountered during this
18377 verification process. Please refer to your SSL library's documentation to
18378 find the exhaustive list of error codes.
Willy Tarreauc735a072011-03-29 00:57:02 +020018379
Willy Tarreau74ca5042013-06-11 23:12:07 +020018380ssl_c_ca_err_depth : integer
18381 When the incoming connection was made over an SSL/TLS transport layer,
18382 returns the depth in the CA chain of the first error detected during the
18383 verification of the client certificate. If no error is encountered, 0 is
18384 returned.
Willy Tarreau0ba27502007-12-24 16:55:16 +010018385
Christopher Faulet70d10d12020-11-06 12:10:33 +010018386ssl_c_chain_der : binary
William Dauchya598b502020-08-06 18:11:38 +020018387 Returns the DER formatted chain certificate presented by the client when the
18388 incoming connection was made over an SSL/TLS transport layer. When used for
18389 an ACL, the value(s) to match against can be passed in hexadecimal form. One
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +050018390 can parse the result with any lib accepting ASN.1 DER data. It currently
William Dauchya598b502020-08-06 18:11:38 +020018391 does not support resumed sessions.
18392
Christopher Faulet70d10d12020-11-06 12:10:33 +010018393ssl_c_der : binary
18394 Returns the DER formatted certificate presented by the client when the
18395 incoming connection was made over an SSL/TLS transport layer. When used for
18396 an ACL, the value(s) to match against can be passed in hexadecimal form.
18397
Willy Tarreau74ca5042013-06-11 23:12:07 +020018398ssl_c_err : integer
18399 When the incoming connection was made over an SSL/TLS transport layer,
18400 returns the ID of the first error detected during verification at depth 0, or
18401 0 if no error was encountered during this verification process. Please refer
18402 to your SSL library's documentation to find the exhaustive list of error
18403 codes.
Willy Tarreau62644772008-07-16 18:36:06 +020018404
Elliot Otchet71f82972020-01-15 08:12:14 -050018405ssl_c_i_dn([<entry>[,<occ>[,<format>]]]) : string
Willy Tarreau74ca5042013-06-11 23:12:07 +020018406 When the incoming connection was made over an SSL/TLS transport layer,
18407 returns the full distinguished name of the issuer of the certificate
18408 presented by the client when no <entry> is specified, or the value of the
18409 first given entry found from the beginning of the DN. If a positive/negative
18410 occurrence number is specified as the optional second argument, it returns
18411 the value of the nth given entry value from the beginning/end of the DN.
18412 For instance, "ssl_c_i_dn(OU,2)" the second organization unit, and
18413 "ssl_c_i_dn(CN)" retrieves the common name.
Elliot Otchet71f82972020-01-15 08:12:14 -050018414 The <format> parameter allows you to receive the DN suitable for
18415 consumption by different protocols. Currently supported is rfc2253 for
18416 LDAP v3.
18417 If you'd like to modify the format only you can specify an empty string
18418 and zero for the first two parameters. Example: ssl_c_i_dn(,0,rfc2253)
Willy Tarreau62644772008-07-16 18:36:06 +020018419
Willy Tarreau74ca5042013-06-11 23:12:07 +020018420ssl_c_key_alg : string
18421 Returns the name of the algorithm used to generate the key of the certificate
18422 presented by the client when the incoming connection was made over an SSL/TLS
18423 transport layer.
Willy Tarreau62644772008-07-16 18:36:06 +020018424
Willy Tarreau74ca5042013-06-11 23:12:07 +020018425ssl_c_notafter : string
18426 Returns the end date presented by the client as a formatted string
18427 YYMMDDhhmmss[Z] when the incoming connection was made over an SSL/TLS
18428 transport layer.
Emeric Brunbede3d02009-06-30 17:54:00 +020018429
Willy Tarreau74ca5042013-06-11 23:12:07 +020018430ssl_c_notbefore : string
18431 Returns the start date presented by the client as a formatted string
18432 YYMMDDhhmmss[Z] when the incoming connection was made over an SSL/TLS
18433 transport layer.
Willy Tarreaub6672b52011-12-12 17:23:41 +010018434
Elliot Otchet71f82972020-01-15 08:12:14 -050018435ssl_c_s_dn([<entry>[,<occ>[,<format>]]]) : string
Willy Tarreau74ca5042013-06-11 23:12:07 +020018436 When the incoming connection was made over an SSL/TLS transport layer,
18437 returns the full distinguished name of the subject of the certificate
18438 presented by the client when no <entry> is specified, or the value of the
18439 first given entry found from the beginning of the DN. If a positive/negative
18440 occurrence number is specified as the optional second argument, it returns
18441 the value of the nth given entry value from the beginning/end of the DN.
18442 For instance, "ssl_c_s_dn(OU,2)" the second organization unit, and
18443 "ssl_c_s_dn(CN)" retrieves the common name.
Elliot Otchet71f82972020-01-15 08:12:14 -050018444 The <format> parameter allows you to receive the DN suitable for
18445 consumption by different protocols. Currently supported is rfc2253 for
18446 LDAP v3.
18447 If you'd like to modify the format only you can specify an empty string
18448 and zero for the first two parameters. Example: ssl_c_s_dn(,0,rfc2253)
Willy Tarreaub6672b52011-12-12 17:23:41 +010018449
Willy Tarreau74ca5042013-06-11 23:12:07 +020018450ssl_c_serial : binary
18451 Returns the serial of the certificate presented by the client when the
18452 incoming connection was made over an SSL/TLS transport layer. When used for
18453 an ACL, the value(s) to match against can be passed in hexadecimal form.
Emeric Brun2525b6b2012-10-18 15:59:43 +020018454
Willy Tarreau74ca5042013-06-11 23:12:07 +020018455ssl_c_sha1 : binary
18456 Returns the SHA-1 fingerprint of the certificate presented by the client when
18457 the incoming connection was made over an SSL/TLS transport layer. This can be
18458 used to stick a client to a server, or to pass this information to a server.
Willy Tarreau2d0caa32014-07-02 19:01:22 +020018459 Note that the output is binary, so if you want to pass that signature to the
18460 server, you need to encode it in hex or base64, such as in the example below:
18461
Jarno Huuskonen676f6222017-03-30 09:19:45 +030018462 Example:
Willy Tarreau2d0caa32014-07-02 19:01:22 +020018463 http-request set-header X-SSL-Client-SHA1 %[ssl_c_sha1,hex]
Emeric Brun2525b6b2012-10-18 15:59:43 +020018464
Willy Tarreau74ca5042013-06-11 23:12:07 +020018465ssl_c_sig_alg : string
18466 Returns the name of the algorithm used to sign the certificate presented by
18467 the client when the incoming connection was made over an SSL/TLS transport
18468 layer.
Emeric Brun87855892012-10-17 17:39:35 +020018469
Willy Tarreau74ca5042013-06-11 23:12:07 +020018470ssl_c_used : boolean
18471 Returns true if current SSL session uses a client certificate even if current
18472 connection uses SSL session resumption. See also "ssl_fc_has_crt".
Emeric Brun7f56e742012-10-19 18:15:40 +020018473
Willy Tarreau74ca5042013-06-11 23:12:07 +020018474ssl_c_verify : integer
18475 Returns the verify result error ID when the incoming connection was made over
18476 an SSL/TLS transport layer, otherwise zero if no error is encountered. Please
18477 refer to your SSL library's documentation for an exhaustive list of error
18478 codes.
Emeric Brunce5ad802012-10-22 14:11:22 +020018479
Willy Tarreau74ca5042013-06-11 23:12:07 +020018480ssl_c_version : integer
18481 Returns the version of the certificate presented by the client when the
18482 incoming connection was made over an SSL/TLS transport layer.
Emeric Brunce5ad802012-10-22 14:11:22 +020018483
Emeric Brun43e79582014-10-29 19:03:26 +010018484ssl_f_der : binary
18485 Returns the DER formatted certificate presented by the frontend when the
18486 incoming connection was made over an SSL/TLS transport layer. When used for
18487 an ACL, the value(s) to match against can be passed in hexadecimal form.
18488
Elliot Otchet71f82972020-01-15 08:12:14 -050018489ssl_f_i_dn([<entry>[,<occ>[,<format>]]]) : string
Willy Tarreau74ca5042013-06-11 23:12:07 +020018490 When the incoming connection was made over an SSL/TLS transport layer,
18491 returns the full distinguished name of the issuer of the certificate
18492 presented by the frontend when no <entry> is specified, or the value of the
18493 first given entry found from the beginning of the DN. If a positive/negative
Emeric Brun87855892012-10-17 17:39:35 +020018494 occurrence number is specified as the optional second argument, it returns
Willy Tarreau74ca5042013-06-11 23:12:07 +020018495 the value of the nth given entry value from the beginning/end of the DN.
18496 For instance, "ssl_f_i_dn(OU,2)" the second organization unit, and
18497 "ssl_f_i_dn(CN)" retrieves the common name.
Elliot Otchet71f82972020-01-15 08:12:14 -050018498 The <format> parameter allows you to receive the DN suitable for
18499 consumption by different protocols. Currently supported is rfc2253 for
18500 LDAP v3.
18501 If you'd like to modify the format only you can specify an empty string
18502 and zero for the first two parameters. Example: ssl_f_i_dn(,0,rfc2253)
Emeric Brun87855892012-10-17 17:39:35 +020018503
Willy Tarreau74ca5042013-06-11 23:12:07 +020018504ssl_f_key_alg : string
18505 Returns the name of the algorithm used to generate the key of the certificate
18506 presented by the frontend when the incoming connection was made over an
18507 SSL/TLS transport layer.
Emeric Brun7f56e742012-10-19 18:15:40 +020018508
Willy Tarreau74ca5042013-06-11 23:12:07 +020018509ssl_f_notafter : string
18510 Returns the end date presented by the frontend as a formatted string
18511 YYMMDDhhmmss[Z] when the incoming connection was made over an SSL/TLS
18512 transport layer.
Emeric Brun2525b6b2012-10-18 15:59:43 +020018513
Willy Tarreau74ca5042013-06-11 23:12:07 +020018514ssl_f_notbefore : string
18515 Returns the start date presented by the frontend as a formatted string
18516 YYMMDDhhmmss[Z] when the incoming connection was made over an SSL/TLS
18517 transport layer.
Emeric Brun87855892012-10-17 17:39:35 +020018518
Elliot Otchet71f82972020-01-15 08:12:14 -050018519ssl_f_s_dn([<entry>[,<occ>[,<format>]]]) : string
Willy Tarreau74ca5042013-06-11 23:12:07 +020018520 When the incoming connection was made over an SSL/TLS transport layer,
18521 returns the full distinguished name of the subject of the certificate
18522 presented by the frontend when no <entry> is specified, or the value of the
18523 first given entry found from the beginning of the DN. If a positive/negative
18524 occurrence number is specified as the optional second argument, it returns
18525 the value of the nth given entry value from the beginning/end of the DN.
18526 For instance, "ssl_f_s_dn(OU,2)" the second organization unit, and
18527 "ssl_f_s_dn(CN)" retrieves the common name.
Elliot Otchet71f82972020-01-15 08:12:14 -050018528 The <format> parameter allows you to receive the DN suitable for
18529 consumption by different protocols. Currently supported is rfc2253 for
18530 LDAP v3.
18531 If you'd like to modify the format only you can specify an empty string
18532 and zero for the first two parameters. Example: ssl_f_s_dn(,0,rfc2253)
Emeric Brunce5ad802012-10-22 14:11:22 +020018533
Willy Tarreau74ca5042013-06-11 23:12:07 +020018534ssl_f_serial : binary
18535 Returns the serial of the certificate presented by the frontend when the
18536 incoming connection was made over an SSL/TLS transport layer. When used for
18537 an ACL, the value(s) to match against can be passed in hexadecimal form.
Emeric Brun87855892012-10-17 17:39:35 +020018538
Emeric Brun55f4fa82014-04-30 17:11:25 +020018539ssl_f_sha1 : binary
18540 Returns the SHA-1 fingerprint of the certificate presented by the frontend
18541 when the incoming connection was made over an SSL/TLS transport layer. This
18542 can be used to know which certificate was chosen using SNI.
18543
Willy Tarreau74ca5042013-06-11 23:12:07 +020018544ssl_f_sig_alg : string
18545 Returns the name of the algorithm used to sign the certificate presented by
18546 the frontend when the incoming connection was made over an SSL/TLS transport
18547 layer.
Emeric Brun7f56e742012-10-19 18:15:40 +020018548
Willy Tarreau74ca5042013-06-11 23:12:07 +020018549ssl_f_version : integer
18550 Returns the version of the certificate presented by the frontend when the
18551 incoming connection was made over an SSL/TLS transport layer.
18552
18553ssl_fc : boolean
Emeric Brun2525b6b2012-10-18 15:59:43 +020018554 Returns true when the front connection was made via an SSL/TLS transport
18555 layer and is locally deciphered. This means it has matched a socket declared
18556 with a "bind" line having the "ssl" option.
18557
Willy Tarreau74ca5042013-06-11 23:12:07 +020018558 Example :
18559 # This passes "X-Proto: https" to servers when client connects over SSL
18560 listen http-https
18561 bind :80
18562 bind :443 ssl crt /etc/haproxy.pem
18563 http-request add-header X-Proto https if { ssl_fc }
18564
18565ssl_fc_alg_keysize : integer
18566 Returns the symmetric cipher key size supported in bits when the incoming
18567 connection was made over an SSL/TLS transport layer.
18568
18569ssl_fc_alpn : string
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030018570 This extracts the Application Layer Protocol Negotiation field from an
Willy Tarreau74ca5042013-06-11 23:12:07 +020018571 incoming connection made via a TLS transport layer and locally deciphered by
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018572 HAProxy. The result is a string containing the protocol name advertised by
Willy Tarreau74ca5042013-06-11 23:12:07 +020018573 the client. The SSL library must have been built with support for TLS
18574 extensions enabled (check haproxy -vv). Note that the TLS ALPN extension is
18575 not advertised unless the "alpn" keyword on the "bind" line specifies a
18576 protocol list. Also, nothing forces the client to pick a protocol from this
18577 list, any other one may be requested. The TLS ALPN extension is meant to
18578 replace the TLS NPN extension. See also "ssl_fc_npn".
18579
Willy Tarreau74ca5042013-06-11 23:12:07 +020018580ssl_fc_cipher : string
18581 Returns the name of the used cipher when the incoming connection was made
18582 over an SSL/TLS transport layer.
Willy Tarreauab861d32013-04-02 02:30:41 +020018583
Thierry FOURNIER5bf77322017-02-25 12:45:22 +010018584ssl_fc_cipherlist_bin : binary
18585 Returns the binary form of the client hello cipher list. The maximum returned
18586 value length is according with the value of
Emmanuel Hocdetaaee7502017-03-07 18:34:58 +010018587 "tune.ssl.capture-cipherlist-size".
Thierry FOURNIER5bf77322017-02-25 12:45:22 +010018588
18589ssl_fc_cipherlist_hex : string
18590 Returns the binary form of the client hello cipher list encoded as
18591 hexadecimal. The maximum returned value length is according with the value of
Emmanuel Hocdetaaee7502017-03-07 18:34:58 +010018592 "tune.ssl.capture-cipherlist-size".
Thierry FOURNIER5bf77322017-02-25 12:45:22 +010018593
18594ssl_fc_cipherlist_str : string
18595 Returns the decoded text form of the client hello cipher list. The maximum
18596 number of ciphers returned is according with the value of
18597 "tune.ssl.capture-cipherlist-size". Note that this sample-fetch is only
Davor Ocelice9ed2812017-12-25 17:49:28 +010018598 available with OpenSSL >= 1.0.2. If the function is not enabled, this
Emmanuel Hocdetddcde192017-09-01 17:32:08 +020018599 sample-fetch returns the hash like "ssl_fc_cipherlist_xxh".
Thierry FOURNIER5bf77322017-02-25 12:45:22 +010018600
18601ssl_fc_cipherlist_xxh : integer
18602 Returns a xxh64 of the cipher list. This hash can be return only is the value
18603 "tune.ssl.capture-cipherlist-size" is set greater than 0, however the hash
Emmanuel Hocdetaaee7502017-03-07 18:34:58 +010018604 take in account all the data of the cipher list.
Thierry FOURNIER5bf77322017-02-25 12:45:22 +010018605
Patrick Hemmer65674662019-06-04 08:13:03 -040018606ssl_fc_client_random : binary
18607 Returns the client random of the front connection when the incoming connection
18608 was made over an SSL/TLS transport layer. It is useful to to decrypt traffic
18609 sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or BoringSSL.
18610
William Lallemand7d42ef52020-07-06 11:41:30 +020018611ssl_fc_client_early_traffic_secret : string
18612 Return the CLIENT_EARLY_TRAFFIC_SECRET as an hexadecimal string for the
18613 front connection when the incoming connection was made over a TLS 1.3
18614 transport layer.
18615 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18616 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18617 activated with "tune.ssl.keylog on" in the global section. See also
18618 "tune.ssl.keylog"
18619
18620ssl_fc_client_handshake_traffic_secret : string
18621 Return the CLIENT_HANDSHAKE_TRAFFIC_SECRET as an hexadecimal string for the
18622 front connection when the incoming connection was made over a TLS 1.3
18623 transport layer.
18624 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18625 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18626 activated with "tune.ssl.keylog on" in the global section. See also
18627 "tune.ssl.keylog"
18628
18629ssl_fc_client_traffic_secret_0 : string
18630 Return the CLIENT_TRAFFIC_SECRET_0 as an hexadecimal string for the
18631 front connection when the incoming connection was made over a TLS 1.3
18632 transport layer.
18633 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18634 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18635 activated with "tune.ssl.keylog on" in the global section. See also
18636 "tune.ssl.keylog"
18637
18638ssl_fc_exporter_secret : string
18639 Return the EXPORTER_SECRET as an hexadecimal string for the
18640 front connection when the incoming connection was made over a TLS 1.3
18641 transport layer.
18642 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18643 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18644 activated with "tune.ssl.keylog on" in the global section. See also
18645 "tune.ssl.keylog"
18646
18647ssl_fc_early_exporter_secret : string
18648 Return the EARLY_EXPORTER_SECRET as an hexadecimal string for the
18649 front connection when the incoming connection was made over an TLS 1.3
18650 transport layer.
18651 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18652 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18653 activated with "tune.ssl.keylog on" in the global section. See also
18654 "tune.ssl.keylog"
18655
Willy Tarreau74ca5042013-06-11 23:12:07 +020018656ssl_fc_has_crt : boolean
Emeric Brun2525b6b2012-10-18 15:59:43 +020018657 Returns true if a client certificate is present in an incoming connection over
18658 SSL/TLS transport layer. Useful if 'verify' statement is set to 'optional'.
Emeric Brun9143d372012-12-20 15:44:16 +010018659 Note: on SSL session resumption with Session ID or TLS ticket, client
18660 certificate is not present in the current connection but may be retrieved
18661 from the cache or the ticket. So prefer "ssl_c_used" if you want to check if
18662 current SSL session uses a client certificate.
Emeric Brun2525b6b2012-10-18 15:59:43 +020018663
Olivier Houchardccaa7de2017-10-02 11:51:03 +020018664ssl_fc_has_early : boolean
18665 Returns true if early data were sent, and the handshake didn't happen yet. As
18666 it has security implications, it is useful to be able to refuse those, or
18667 wait until the handshake happened.
18668
Willy Tarreau74ca5042013-06-11 23:12:07 +020018669ssl_fc_has_sni : boolean
18670 This checks for the presence of a Server Name Indication TLS extension (SNI)
Willy Tarreauf7bc57c2012-10-03 00:19:48 +020018671 in an incoming connection was made over an SSL/TLS transport layer. Returns
18672 true when the incoming connection presents a TLS SNI field. This requires
John Roeslerfb2fce12019-07-10 15:45:51 -050018673 that the SSL library is built with support for TLS extensions enabled (check
Willy Tarreauf7bc57c2012-10-03 00:19:48 +020018674 haproxy -vv).
Willy Tarreau7875d092012-09-10 08:20:03 +020018675
Nenad Merdanovic1516fe32016-05-17 03:31:21 +020018676ssl_fc_is_resumed : boolean
Nenad Merdanovic26ea8222015-05-18 02:28:57 +020018677 Returns true if the SSL/TLS session has been resumed through the use of
Jérôme Magnin4a326cb2018-01-15 14:01:17 +010018678 SSL session cache or TLS tickets on an incoming connection over an SSL/TLS
18679 transport layer.
Nenad Merdanovic26ea8222015-05-18 02:28:57 +020018680
Willy Tarreau74ca5042013-06-11 23:12:07 +020018681ssl_fc_npn : string
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030018682 This extracts the Next Protocol Negotiation field from an incoming connection
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018683 made via a TLS transport layer and locally deciphered by HAProxy. The result
Willy Tarreau74ca5042013-06-11 23:12:07 +020018684 is a string containing the protocol name advertised by the client. The SSL
18685 library must have been built with support for TLS extensions enabled (check
18686 haproxy -vv). Note that the TLS NPN extension is not advertised unless the
18687 "npn" keyword on the "bind" line specifies a protocol list. Also, nothing
18688 forces the client to pick a protocol from this list, any other one may be
18689 requested. Please note that the TLS NPN extension was replaced with ALPN.
Willy Tarreaua33c6542012-10-15 13:19:06 +020018690
Willy Tarreau74ca5042013-06-11 23:12:07 +020018691ssl_fc_protocol : string
18692 Returns the name of the used protocol when the incoming connection was made
18693 over an SSL/TLS transport layer.
Willy Tarreau7875d092012-09-10 08:20:03 +020018694
Emeric Brunb73a9b02014-04-30 18:49:19 +020018695ssl_fc_unique_id : binary
David Sc1ad52e2014-04-08 18:48:47 -040018696 When the incoming connection was made over an SSL/TLS transport layer,
Emeric Brunb73a9b02014-04-30 18:49:19 +020018697 returns the TLS unique ID as defined in RFC5929 section 3. The unique id
18698 can be encoded to base64 using the converter: "ssl_bc_unique_id,base64".
David Sc1ad52e2014-04-08 18:48:47 -040018699
William Lallemand7d42ef52020-07-06 11:41:30 +020018700ssl_fc_server_handshake_traffic_secret : string
18701 Return the SERVER_HANDSHAKE_TRAFFIC_SECRET as an hexadecimal string for the
18702 front connection when the incoming connection was made over a TLS 1.3
18703 transport layer.
18704 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18705 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18706 activated with "tune.ssl.keylog on" in the global section. See also
18707 "tune.ssl.keylog"
18708
18709ssl_fc_server_traffic_secret_0 : string
18710 Return the SERVER_TRAFFIC_SECRET_0 as an hexadecimal string for the
18711 front connection when the incoming connection was made over an TLS 1.3
18712 transport layer.
18713 Require OpenSSL >= 1.1.1. This is one of the keys dumped by the OpenSSL
18714 keylog callback to generate the SSLKEYLOGFILE. The SSL Key logging must be
18715 activated with "tune.ssl.keylog on" in the global section. See also
18716 "tune.ssl.keylog"
18717
Patrick Hemmer65674662019-06-04 08:13:03 -040018718ssl_fc_server_random : binary
18719 Returns the server random of the front connection when the incoming connection
18720 was made over an SSL/TLS transport layer. It is useful to to decrypt traffic
18721 sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or BoringSSL.
18722
Willy Tarreau74ca5042013-06-11 23:12:07 +020018723ssl_fc_session_id : binary
18724 Returns the SSL ID of the front connection when the incoming connection was
18725 made over an SSL/TLS transport layer. It is useful to stick a given client to
18726 a server. It is important to note that some browsers refresh their session ID
18727 every few minutes.
Willy Tarreau7875d092012-09-10 08:20:03 +020018728
Patrick Hemmere0275472018-04-28 19:15:51 -040018729ssl_fc_session_key : binary
18730 Returns the SSL session master key of the front connection when the incoming
18731 connection was made over an SSL/TLS transport layer. It is useful to decrypt
18732 traffic sent using ephemeral ciphers. This requires OpenSSL >= 1.1.0, or
18733 BoringSSL.
18734
18735
Willy Tarreau74ca5042013-06-11 23:12:07 +020018736ssl_fc_sni : string
18737 This extracts the Server Name Indication TLS extension (SNI) field from an
18738 incoming connection made via an SSL/TLS transport layer and locally
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018739 deciphered by HAProxy. The result (when present) typically is a string
Willy Tarreau74ca5042013-06-11 23:12:07 +020018740 matching the HTTPS host name (253 chars or less). The SSL library must have
18741 been built with support for TLS extensions enabled (check haproxy -vv).
18742
Alex18c88772021-06-05 13:23:08 +020018743 This fetch is different from "req.ssl_sni" above in that it applies to the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018744 connection being deciphered by HAProxy and not to SSL contents being blindly
Willy Tarreau74ca5042013-06-11 23:12:07 +020018745 forwarded. See also "ssl_fc_sni_end" and "ssl_fc_sni_reg" below. This
John Roeslerfb2fce12019-07-10 15:45:51 -050018746 requires that the SSL library is built with support for TLS extensions
Cyril Bonté9c1eb1e2012-10-09 22:45:34 +020018747 enabled (check haproxy -vv).
Willy Tarreau62644772008-07-16 18:36:06 +020018748
Willy Tarreau74ca5042013-06-11 23:12:07 +020018749 ACL derivatives :
Willy Tarreau74ca5042013-06-11 23:12:07 +020018750 ssl_fc_sni_end : suffix match
18751 ssl_fc_sni_reg : regex match
Emeric Brun589fcad2012-10-16 14:13:26 +020018752
Willy Tarreau74ca5042013-06-11 23:12:07 +020018753ssl_fc_use_keysize : integer
18754 Returns the symmetric cipher key size used in bits when the incoming
18755 connection was made over an SSL/TLS transport layer.
Willy Tarreaub6fb4202008-07-20 11:18:28 +020018756
William Lallemandbfa3e812020-06-25 20:07:18 +020018757ssl_s_der : binary
18758 Returns the DER formatted certificate presented by the server when the
18759 outgoing connection was made over an SSL/TLS transport layer. When used for
18760 an ACL, the value(s) to match against can be passed in hexadecimal form.
18761
William Dauchya598b502020-08-06 18:11:38 +020018762ssl_s_chain_der : binary
18763 Returns the DER formatted chain certificate presented by the server when the
18764 outgoing connection was made over an SSL/TLS transport layer. When used for
18765 an ACL, the value(s) to match against can be passed in hexadecimal form. One
Ilya Shipitsin2272d8a2020-12-21 01:22:40 +050018766 can parse the result with any lib accepting ASN.1 DER data. It currently
William Dauchya598b502020-08-06 18:11:38 +020018767 does not support resumed sessions.
18768
William Lallemandbfa3e812020-06-25 20:07:18 +020018769ssl_s_key_alg : string
18770 Returns the name of the algorithm used to generate the key of the certificate
18771 presented by the server when the outgoing connection was made over an
18772 SSL/TLS transport layer.
18773
18774ssl_s_notafter : string
18775 Returns the end date presented by the server as a formatted string
18776 YYMMDDhhmmss[Z] when the outgoing connection was made over an SSL/TLS
18777 transport layer.
18778
18779ssl_s_notbefore : string
18780 Returns the start date presented by the server as a formatted string
18781 YYMMDDhhmmss[Z] when the outgoing connection was made over an SSL/TLS
18782 transport layer.
18783
18784ssl_s_i_dn([<entry>[,<occ>[,<format>]]]) : string
18785 When the outgoing connection was made over an SSL/TLS transport layer,
18786 returns the full distinguished name of the issuer of the certificate
18787 presented by the server when no <entry> is specified, or the value of the
18788 first given entry found from the beginning of the DN. If a positive/negative
18789 occurrence number is specified as the optional second argument, it returns
18790 the value of the nth given entry value from the beginning/end of the DN.
William Lallemand8f600c82020-06-26 09:55:06 +020018791 For instance, "ssl_s_i_dn(OU,2)" the second organization unit, and
18792 "ssl_s_i_dn(CN)" retrieves the common name.
William Lallemandbfa3e812020-06-25 20:07:18 +020018793 The <format> parameter allows you to receive the DN suitable for
18794 consumption by different protocols. Currently supported is rfc2253 for
18795 LDAP v3.
18796 If you'd like to modify the format only you can specify an empty string
18797 and zero for the first two parameters. Example: ssl_s_i_dn(,0,rfc2253)
18798
18799ssl_s_s_dn([<entry>[,<occ>[,<format>]]]) : string
18800 When the outgoing connection was made over an SSL/TLS transport layer,
18801 returns the full distinguished name of the subject of the certificate
18802 presented by the server when no <entry> is specified, or the value of the
18803 first given entry found from the beginning of the DN. If a positive/negative
18804 occurrence number is specified as the optional second argument, it returns
18805 the value of the nth given entry value from the beginning/end of the DN.
William Lallemand8f600c82020-06-26 09:55:06 +020018806 For instance, "ssl_s_s_dn(OU,2)" the second organization unit, and
18807 "ssl_s_s_dn(CN)" retrieves the common name.
William Lallemandbfa3e812020-06-25 20:07:18 +020018808 The <format> parameter allows you to receive the DN suitable for
18809 consumption by different protocols. Currently supported is rfc2253 for
18810 LDAP v3.
18811 If you'd like to modify the format only you can specify an empty string
18812 and zero for the first two parameters. Example: ssl_s_s_dn(,0,rfc2253)
18813
18814ssl_s_serial : binary
18815 Returns the serial of the certificate presented by the server when the
18816 outgoing connection was made over an SSL/TLS transport layer. When used for
18817 an ACL, the value(s) to match against can be passed in hexadecimal form.
18818
18819ssl_s_sha1 : binary
18820 Returns the SHA-1 fingerprint of the certificate presented by the server
18821 when the outgoing connection was made over an SSL/TLS transport layer. This
18822 can be used to know which certificate was chosen using SNI.
18823
18824ssl_s_sig_alg : string
18825 Returns the name of the algorithm used to sign the certificate presented by
18826 the server when the outgoing connection was made over an SSL/TLS transport
18827 layer.
18828
18829ssl_s_version : integer
18830 Returns the version of the certificate presented by the server when the
18831 outgoing connection was made over an SSL/TLS transport layer.
Willy Tarreaub6fb4202008-07-20 11:18:28 +020018832
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200188337.3.5. Fetching samples from buffer contents (Layer 6)
Willy Tarreau74ca5042013-06-11 23:12:07 +020018834------------------------------------------------------
Willy Tarreaub6fb4202008-07-20 11:18:28 +020018835
Willy Tarreau74ca5042013-06-11 23:12:07 +020018836Fetching samples from buffer contents is a bit different from the previous
18837sample fetches above because the sampled data are ephemeral. These data can
18838only be used when they're available and will be lost when they're forwarded.
18839For this reason, samples fetched from buffer contents during a request cannot
18840be used in a response for example. Even while the data are being fetched, they
18841can change. Sometimes it is necessary to set some delays or combine multiple
18842sample fetch methods to ensure that the expected data are complete and usable,
18843for example through TCP request content inspection. Please see the "tcp-request
18844content" keyword for more detailed information on the subject.
Willy Tarreau62644772008-07-16 18:36:06 +020018845
Christopher Fauleta434a002021-03-25 11:58:51 +010018846Warning : Following sample fetches are ignored if used from HTTP proxies. They
18847 only deal with raw contents found in the buffers. On their side,
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018848 HTTP proxies use structured content. Thus raw representation of
Christopher Fauleta434a002021-03-25 11:58:51 +010018849 these data are meaningless. A warning is emitted if an ACL relies on
18850 one of the following sample fetches. But it is not possible to detect
18851 all invalid usage (for instance inside a log-format string or a
18852 sample expression). So be careful.
18853
Willy Tarreau74ca5042013-06-11 23:12:07 +020018854payload(<offset>,<length>) : binary (deprecated)
Davor Ocelice9ed2812017-12-25 17:49:28 +010018855 This is an alias for "req.payload" when used in the context of a request (e.g.
Willy Tarreau74ca5042013-06-11 23:12:07 +020018856 "stick on", "stick match"), and for "res.payload" when used in the context of
18857 a response such as in "stick store response".
Willy Tarreau0ba27502007-12-24 16:55:16 +010018858
Willy Tarreau74ca5042013-06-11 23:12:07 +020018859payload_lv(<offset1>,<length>[,<offset2>]) : binary (deprecated)
18860 This is an alias for "req.payload_lv" when used in the context of a request
Davor Ocelice9ed2812017-12-25 17:49:28 +010018861 (e.g. "stick on", "stick match"), and for "res.payload_lv" when used in the
Willy Tarreau74ca5042013-06-11 23:12:07 +020018862 context of a response such as in "stick store response".
Willy Tarreau0ba27502007-12-24 16:55:16 +010018863
Willy Tarreau74ca5042013-06-11 23:12:07 +020018864req.len : integer
18865req_len : integer (deprecated)
18866 Returns an integer value corresponding to the number of bytes present in the
18867 request buffer. This is mostly used in ACL. It is important to understand
18868 that this test does not return false as long as the buffer is changing. This
18869 means that a check with equality to zero will almost always immediately match
18870 at the beginning of the session, while a test for more data will wait for
Daniel Corbett9f0843f2021-05-08 10:50:37 -040018871 that data to come in and return false only when HAProxy is certain that no
Willy Tarreau74ca5042013-06-11 23:12:07 +020018872 more data will come in. This test was designed to be used with TCP request
18873 content inspection.
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018874
Willy Tarreau74ca5042013-06-11 23:12:07 +020018875req.payload(<offset>,<length>) : binary
18876 This extracts a binary block of <length> bytes and starting at byte <offset>
Willy Tarreau00f00842013-08-02 11:07:32 +020018877 in the request buffer. As a special case, if the <length> argument is zero,
18878 the the whole buffer from <offset> to the end is extracted. This can be used
18879 with ACLs in order to check for the presence of some content in a buffer at
18880 any location.
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018881
Willy Tarreau74ca5042013-06-11 23:12:07 +020018882 ACL alternatives :
18883 payload(<offset>,<length>) : hex binary match
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018884
Willy Tarreau74ca5042013-06-11 23:12:07 +020018885req.payload_lv(<offset1>,<length>[,<offset2>]) : binary
18886 This extracts a binary block whose size is specified at <offset1> for <length>
18887 bytes, and which starts at <offset2> if specified or just after the length in
18888 the request buffer. The <offset2> parameter also supports relative offsets if
18889 prepended with a '+' or '-' sign.
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018890
Willy Tarreau74ca5042013-06-11 23:12:07 +020018891 ACL alternatives :
18892 payload_lv(<offset1>,<length>[,<offset2>]) : hex binary match
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018893
Willy Tarreau74ca5042013-06-11 23:12:07 +020018894 Example : please consult the example from the "stick store-response" keyword.
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018895
Willy Tarreau74ca5042013-06-11 23:12:07 +020018896req.proto_http : boolean
18897req_proto_http : boolean (deprecated)
18898 Returns true when data in the request buffer look like HTTP and correctly
18899 parses as such. It is the same parser as the common HTTP request parser which
18900 is used so there should be no surprises. The test does not match until the
18901 request is complete, failed or timed out. This test may be used to report the
18902 protocol in TCP logs, but the biggest use is to block TCP request analysis
18903 until a complete HTTP request is present in the buffer, for example to track
18904 a header.
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018905
Willy Tarreau74ca5042013-06-11 23:12:07 +020018906 Example:
18907 # track request counts per "base" (concatenation of Host+URL)
18908 tcp-request inspect-delay 10s
18909 tcp-request content reject if !HTTP
Willy Tarreaube4a3ef2013-06-17 15:04:07 +020018910 tcp-request content track-sc0 base table req-rate
Willy Tarreaua7ad50c2012-04-29 15:39:40 +020018911
Willy Tarreau74ca5042013-06-11 23:12:07 +020018912req.rdp_cookie([<name>]) : string
18913rdp_cookie([<name>]) : string (deprecated)
18914 When the request buffer looks like the RDP protocol, extracts the RDP cookie
18915 <name>, or any cookie if unspecified. The parser only checks for the first
18916 cookie, as illustrated in the RDP protocol specification. The cookie name is
18917 case insensitive. Generally the "MSTS" cookie name will be used, as it can
18918 contain the user name of the client connecting to the server if properly
18919 configured on the client. The "MSTSHASH" cookie is often used as well for
18920 session stickiness to servers.
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018921
Willy Tarreau74ca5042013-06-11 23:12:07 +020018922 This differs from "balance rdp-cookie" in that any balancing algorithm may be
18923 used and thus the distribution of clients to backend servers is not linked to
18924 a hash of the RDP cookie. It is envisaged that using a balancing algorithm
18925 such as "balance roundrobin" or "balance leastconn" will lead to a more even
18926 distribution of clients to backend servers than the hash used by "balance
18927 rdp-cookie".
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018928
Willy Tarreau74ca5042013-06-11 23:12:07 +020018929 ACL derivatives :
18930 req_rdp_cookie([<name>]) : exact string match
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018931
Willy Tarreau74ca5042013-06-11 23:12:07 +020018932 Example :
18933 listen tse-farm
18934 bind 0.0.0.0:3389
18935 # wait up to 5s for an RDP cookie in the request
18936 tcp-request inspect-delay 5s
18937 tcp-request content accept if RDP_COOKIE
18938 # apply RDP cookie persistence
18939 persist rdp-cookie
18940 # Persist based on the mstshash cookie
18941 # This is only useful makes sense if
18942 # balance rdp-cookie is not used
18943 stick-table type string size 204800
18944 stick on req.rdp_cookie(mstshash)
18945 server srv1 1.1.1.1:3389
18946 server srv1 1.1.1.2:3389
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018947
Willy Tarreau74ca5042013-06-11 23:12:07 +020018948 See also : "balance rdp-cookie", "persist rdp-cookie", "tcp-request" and the
18949 "req_rdp_cookie" ACL.
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018950
Willy Tarreau74ca5042013-06-11 23:12:07 +020018951req.rdp_cookie_cnt([name]) : integer
18952rdp_cookie_cnt([name]) : integer (deprecated)
18953 Tries to parse the request buffer as RDP protocol, then returns an integer
18954 corresponding to the number of RDP cookies found. If an optional cookie name
18955 is passed, only cookies matching this name are considered. This is mostly
18956 used in ACL.
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018957
Willy Tarreau74ca5042013-06-11 23:12:07 +020018958 ACL derivatives :
18959 req_rdp_cookie_cnt([<name>]) : integer match
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018960
Alex Zorin4afdd132018-12-30 13:56:28 +110018961req.ssl_alpn : string
18962 Returns a string containing the values of the Application-Layer Protocol
18963 Negotiation (ALPN) TLS extension (RFC7301), sent by the client within the SSL
18964 ClientHello message. Note that this only applies to raw contents found in the
18965 request buffer and not to the contents deciphered via an SSL data layer, so
18966 this will not work with "bind" lines having the "ssl" option. This is useful
18967 in ACL to make a routing decision based upon the ALPN preferences of a TLS
Jarno Huuskonene504f812019-01-03 07:56:49 +020018968 client, like in the example below. See also "ssl_fc_alpn".
Alex Zorin4afdd132018-12-30 13:56:28 +110018969
18970 Examples :
18971 # Wait for a client hello for at most 5 seconds
18972 tcp-request inspect-delay 5s
18973 tcp-request content accept if { req_ssl_hello_type 1 }
Jarno Huuskonene504f812019-01-03 07:56:49 +020018974 use_backend bk_acme if { req.ssl_alpn acme-tls/1 }
Alex Zorin4afdd132018-12-30 13:56:28 +110018975 default_backend bk_default
18976
Nenad Merdanovic5fc7d7e2015-07-07 22:00:17 +020018977req.ssl_ec_ext : boolean
18978 Returns a boolean identifying if client sent the Supported Elliptic Curves
18979 Extension as defined in RFC4492, section 5.1. within the SSL ClientHello
Cyril Bonté307ee1e2015-09-28 23:16:06 +020018980 message. This can be used to present ECC compatible clients with EC
18981 certificate and to use RSA for all others, on the same IP address. Note that
18982 this only applies to raw contents found in the request buffer and not to
18983 contents deciphered via an SSL data layer, so this will not work with "bind"
18984 lines having the "ssl" option.
Nenad Merdanovic5fc7d7e2015-07-07 22:00:17 +020018985
Willy Tarreau74ca5042013-06-11 23:12:07 +020018986req.ssl_hello_type : integer
18987req_ssl_hello_type : integer (deprecated)
18988 Returns an integer value containing the type of the SSL hello message found
18989 in the request buffer if the buffer contains data that parse as a complete
18990 SSL (v3 or superior) client hello message. Note that this only applies to raw
18991 contents found in the request buffer and not to contents deciphered via an
18992 SSL data layer, so this will not work with "bind" lines having the "ssl"
18993 option. This is mostly used in ACL to detect presence of an SSL hello message
18994 that is supposed to contain an SSL session ID usable for stickiness.
Willy Tarreau04aa6a92012-04-06 18:57:55 +020018995
Willy Tarreau74ca5042013-06-11 23:12:07 +020018996req.ssl_sni : string
18997req_ssl_sni : string (deprecated)
18998 Returns a string containing the value of the Server Name TLS extension sent
18999 by a client in a TLS stream passing through the request buffer if the buffer
19000 contains data that parse as a complete SSL (v3 or superior) client hello
19001 message. Note that this only applies to raw contents found in the request
19002 buffer and not to contents deciphered via an SSL data layer, so this will not
Lukas Tribusa267b5d2020-07-19 00:25:06 +020019003 work with "bind" lines having the "ssl" option. This will only work for actual
19004 implicit TLS based protocols like HTTPS (443), IMAPS (993), SMTPS (465),
19005 however it will not work for explicit TLS based protocols, like SMTP (25/587)
19006 or IMAP (143). SNI normally contains the name of the host the client tries to
19007 connect to (for recent browsers). SNI is useful for allowing or denying access
19008 to certain hosts when SSL/TLS is used by the client. This test was designed to
19009 be used with TCP request content inspection. If content switching is needed,
19010 it is recommended to first wait for a complete client hello (type 1), like in
19011 the example below. See also "ssl_fc_sni".
Willy Tarreau04aa6a92012-04-06 18:57:55 +020019012
Willy Tarreau74ca5042013-06-11 23:12:07 +020019013 ACL derivatives :
Alex18c88772021-06-05 13:23:08 +020019014 req.ssl_sni : exact string match
Willy Tarreau04aa6a92012-04-06 18:57:55 +020019015
Willy Tarreau74ca5042013-06-11 23:12:07 +020019016 Examples :
19017 # Wait for a client hello for at most 5 seconds
19018 tcp-request inspect-delay 5s
19019 tcp-request content accept if { req_ssl_hello_type 1 }
Alex18c88772021-06-05 13:23:08 +020019020 use_backend bk_allow if { req.ssl_sni -f allowed_sites }
Willy Tarreau74ca5042013-06-11 23:12:07 +020019021 default_backend bk_sorry_page
Willy Tarreau04aa6a92012-04-06 18:57:55 +020019022
Pradeep Jindalbb2acf52015-09-29 10:12:57 +053019023req.ssl_st_ext : integer
19024 Returns 0 if the client didn't send a SessionTicket TLS Extension (RFC5077)
19025 Returns 1 if the client sent SessionTicket TLS Extension
19026 Returns 2 if the client also sent non-zero length TLS SessionTicket
19027 Note that this only applies to raw contents found in the request buffer and
19028 not to contents deciphered via an SSL data layer, so this will not work with
19029 "bind" lines having the "ssl" option. This can for example be used to detect
19030 whether the client sent a SessionTicket or not and stick it accordingly, if
19031 no SessionTicket then stick on SessionID or don't stick as there's no server
19032 side state is there when SessionTickets are in use.
19033
Willy Tarreau74ca5042013-06-11 23:12:07 +020019034req.ssl_ver : integer
19035req_ssl_ver : integer (deprecated)
19036 Returns an integer value containing the version of the SSL/TLS protocol of a
19037 stream present in the request buffer. Both SSLv2 hello messages and SSLv3
19038 messages are supported. TLSv1 is announced as SSL version 3.1. The value is
19039 composed of the major version multiplied by 65536, added to the minor
19040 version. Note that this only applies to raw contents found in the request
19041 buffer and not to contents deciphered via an SSL data layer, so this will not
19042 work with "bind" lines having the "ssl" option. The ACL version of the test
Davor Ocelice9ed2812017-12-25 17:49:28 +010019043 matches against a decimal notation in the form MAJOR.MINOR (e.g. 3.1). This
Willy Tarreau74ca5042013-06-11 23:12:07 +020019044 fetch is mostly used in ACL.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019045
Willy Tarreau74ca5042013-06-11 23:12:07 +020019046 ACL derivatives :
19047 req_ssl_ver : decimal match
Willy Tarreaud63335a2010-02-26 12:56:52 +010019048
Willy Tarreau47e8eba2013-09-11 23:28:46 +020019049res.len : integer
19050 Returns an integer value corresponding to the number of bytes present in the
19051 response buffer. This is mostly used in ACL. It is important to understand
19052 that this test does not return false as long as the buffer is changing. This
19053 means that a check with equality to zero will almost always immediately match
19054 at the beginning of the session, while a test for more data will wait for
Daniel Corbett9f0843f2021-05-08 10:50:37 -040019055 that data to come in and return false only when HAProxy is certain that no
Willy Tarreau47e8eba2013-09-11 23:28:46 +020019056 more data will come in. This test was designed to be used with TCP response
Christopher Faulete596d182020-05-05 17:46:34 +020019057 content inspection. But it may also be used in tcp-check based expect rules.
Willy Tarreau47e8eba2013-09-11 23:28:46 +020019058
Willy Tarreau74ca5042013-06-11 23:12:07 +020019059res.payload(<offset>,<length>) : binary
19060 This extracts a binary block of <length> bytes and starting at byte <offset>
Willy Tarreau00f00842013-08-02 11:07:32 +020019061 in the response buffer. As a special case, if the <length> argument is zero,
Christopher Faulete596d182020-05-05 17:46:34 +020019062 the whole buffer from <offset> to the end is extracted. This can be used
Willy Tarreau00f00842013-08-02 11:07:32 +020019063 with ACLs in order to check for the presence of some content in a buffer at
Christopher Faulete596d182020-05-05 17:46:34 +020019064 any location. It may also be used in tcp-check based expect rules.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019065
Willy Tarreau74ca5042013-06-11 23:12:07 +020019066res.payload_lv(<offset1>,<length>[,<offset2>]) : binary
19067 This extracts a binary block whose size is specified at <offset1> for <length>
19068 bytes, and which starts at <offset2> if specified or just after the length in
19069 the response buffer. The <offset2> parameter also supports relative offsets
Christopher Faulete596d182020-05-05 17:46:34 +020019070 if prepended with a '+' or '-' sign. It may also be used in tcp-check based
19071 expect rules.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019072
Willy Tarreau74ca5042013-06-11 23:12:07 +020019073 Example : please consult the example from the "stick store-response" keyword.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019074
Willy Tarreau971f7b62015-09-29 14:06:59 +020019075res.ssl_hello_type : integer
19076rep_ssl_hello_type : integer (deprecated)
19077 Returns an integer value containing the type of the SSL hello message found
19078 in the response buffer if the buffer contains data that parses as a complete
19079 SSL (v3 or superior) hello message. Note that this only applies to raw
19080 contents found in the response buffer and not to contents deciphered via an
19081 SSL data layer, so this will not work with "server" lines having the "ssl"
19082 option. This is mostly used in ACL to detect presence of an SSL hello message
19083 that is supposed to contain an SSL session ID usable for stickiness.
19084
Willy Tarreau74ca5042013-06-11 23:12:07 +020019085wait_end : boolean
19086 This fetch either returns true when the inspection period is over, or does
19087 not fetch. It is only used in ACLs, in conjunction with content analysis to
Davor Ocelice9ed2812017-12-25 17:49:28 +010019088 avoid returning a wrong verdict early. It may also be used to delay some
Willy Tarreau74ca5042013-06-11 23:12:07 +020019089 actions, such as a delayed reject for some special addresses. Since it either
19090 stops the rules evaluation or immediately returns true, it is recommended to
Davor Ocelice9ed2812017-12-25 17:49:28 +010019091 use this acl as the last one in a rule. Please note that the default ACL
Willy Tarreau74ca5042013-06-11 23:12:07 +020019092 "WAIT_END" is always usable without prior declaration. This test was designed
19093 to be used with TCP request content inspection.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019094
Willy Tarreau74ca5042013-06-11 23:12:07 +020019095 Examples :
19096 # delay every incoming request by 2 seconds
19097 tcp-request inspect-delay 2s
19098 tcp-request content accept if WAIT_END
Willy Tarreaud63335a2010-02-26 12:56:52 +010019099
Willy Tarreau74ca5042013-06-11 23:12:07 +020019100 # don't immediately tell bad guys they are rejected
19101 tcp-request inspect-delay 10s
19102 acl goodguys src 10.0.0.0/24
19103 acl badguys src 10.0.1.0/24
19104 tcp-request content accept if goodguys
19105 tcp-request content reject if badguys WAIT_END
19106 tcp-request content reject
19107
19108
Thierry FOURNIER060762e2014-04-23 13:29:15 +0200191097.3.6. Fetching HTTP samples (Layer 7)
Willy Tarreau74ca5042013-06-11 23:12:07 +020019110--------------------------------------
19111
19112It is possible to fetch samples from HTTP contents, requests and responses.
19113This application layer is also called layer 7. It is only possible to fetch the
19114data in this section when a full HTTP request or response has been parsed from
19115its respective request or response buffer. This is always the case with all
19116HTTP specific rules and for sections running with "mode http". When using TCP
19117content inspection, it may be necessary to support an inspection delay in order
19118to let the request or response come in first. These fetches may require a bit
19119more CPU resources than the layer 4 ones, but not much since the request and
19120response are indexed.
19121
Christopher Faulet4d37e532021-03-26 14:44:00 +010019122Note : Regarding HTTP processing from the tcp-request content rules, everything
19123 will work as expected from an HTTP proxy. However, from a TCP proxy,
19124 without an HTTP upgrade, it will only work for HTTP/1 content. For
19125 HTTP/2 content, only the preface is visible. Thus, it is only possible
19126 to rely to "req.proto_http", "req.ver" and eventually "method" sample
19127 fetches. All other L7 sample fetches will fail. After an HTTP upgrade,
19128 they will work in the same manner than from an HTTP proxy.
19129
Willy Tarreau74ca5042013-06-11 23:12:07 +020019130base : string
19131 This returns the concatenation of the first Host header and the path part of
19132 the request, which starts at the first slash and ends before the question
19133 mark. It can be useful in virtual hosted environments to detect URL abuses as
19134 well as to improve shared caches efficiency. Using this with a limited size
19135 stick table also allows one to collect statistics about most commonly
19136 requested objects by host/path. With ACLs it can allow simple content
19137 switching rules involving the host and the path at the same time, such as
19138 "www.example.com/favicon.ico". See also "path" and "uri".
19139
19140 ACL derivatives :
19141 base : exact string match
19142 base_beg : prefix match
19143 base_dir : subdir match
19144 base_dom : domain match
19145 base_end : suffix match
19146 base_len : length match
19147 base_reg : regex match
19148 base_sub : substring match
19149
19150base32 : integer
19151 This returns a 32-bit hash of the value returned by the "base" fetch method
19152 above. This is useful to track per-URL activity on high traffic sites without
19153 having to store all URLs. Instead a shorter hash is stored, saving a lot of
Willy Tarreau23ec4ca2014-07-15 20:15:37 +020019154 memory. The output type is an unsigned integer. The hash function used is
19155 SDBM with full avalanche on the output. Technically, base32 is exactly equal
19156 to "base,sdbm(1)".
Willy Tarreau74ca5042013-06-11 23:12:07 +020019157
19158base32+src : binary
19159 This returns the concatenation of the base32 fetch above and the src fetch
19160 below. The resulting type is of type binary, with a size of 8 or 20 bytes
19161 depending on the source address family. This can be used to track per-IP,
19162 per-URL counters.
19163
Yves Lafonb4d37082021-02-11 11:01:28 +010019164baseq : string
19165 This returns the concatenation of the first Host header and the path part of
19166 the request with the query-string, which starts at the first slash. Using this
19167 instead of "base" allows one to properly identify the target resource, for
19168 statistics or caching use cases. See also "path", "pathq" and "base".
19169
William Lallemand65ad6e12014-01-31 15:08:02 +010019170capture.req.hdr(<idx>) : string
19171 This extracts the content of the header captured by the "capture request
19172 header", idx is the position of the capture keyword in the configuration.
19173 The first entry is an index of 0. See also: "capture request header".
19174
19175capture.req.method : string
19176 This extracts the METHOD of an HTTP request. It can be used in both request
19177 and response. Unlike "method", it can be used in both request and response
19178 because it's allocated.
19179
19180capture.req.uri : string
19181 This extracts the request's URI, which starts at the first slash and ends
19182 before the first space in the request (without the host part). Unlike "path"
19183 and "url", it can be used in both request and response because it's
19184 allocated.
19185
Willy Tarreau3c1b5ec2014-04-24 23:41:57 +020019186capture.req.ver : string
19187 This extracts the request's HTTP version and returns either "HTTP/1.0" or
19188 "HTTP/1.1". Unlike "req.ver", it can be used in both request, response, and
19189 logs because it relies on a persistent flag.
19190
William Lallemand65ad6e12014-01-31 15:08:02 +010019191capture.res.hdr(<idx>) : string
19192 This extracts the content of the header captured by the "capture response
19193 header", idx is the position of the capture keyword in the configuration.
19194 The first entry is an index of 0.
19195 See also: "capture response header"
19196
Willy Tarreau3c1b5ec2014-04-24 23:41:57 +020019197capture.res.ver : string
19198 This extracts the response's HTTP version and returns either "HTTP/1.0" or
19199 "HTTP/1.1". Unlike "res.ver", it can be used in logs because it relies on a
19200 persistent flag.
19201
Willy Tarreaua5910cc2015-05-02 00:46:08 +020019202req.body : binary
Christopher Fauletaf4dc4c2020-05-05 17:33:25 +020019203 This returns the HTTP request's available body as a block of data. It is
19204 recommended to use "option http-buffer-request" to be sure to wait, as much
19205 as possible, for the request's body.
Willy Tarreaua5910cc2015-05-02 00:46:08 +020019206
Thierry FOURNIER9826c772015-05-20 15:50:54 +020019207req.body_param([<name>) : string
19208 This fetch assumes that the body of the POST request is url-encoded. The user
19209 can check if the "content-type" contains the value
19210 "application/x-www-form-urlencoded". This extracts the first occurrence of the
19211 parameter <name> in the body, which ends before '&'. The parameter name is
19212 case-sensitive. If no name is given, any parameter will match, and the first
19213 one will be returned. The result is a string corresponding to the value of the
19214 parameter <name> as presented in the request body (no URL decoding is
19215 performed). Note that the ACL version of this fetch iterates over multiple
19216 parameters and will iteratively report all parameters values if no name is
19217 given.
19218
Willy Tarreaua5910cc2015-05-02 00:46:08 +020019219req.body_len : integer
19220 This returns the length of the HTTP request's available body in bytes. It may
19221 be lower than the advertised length if the body is larger than the buffer. It
Christopher Fauletaf4dc4c2020-05-05 17:33:25 +020019222 is recommended to use "option http-buffer-request" to be sure to wait, as
19223 much as possible, for the request's body.
Willy Tarreaua5910cc2015-05-02 00:46:08 +020019224
19225req.body_size : integer
19226 This returns the advertised length of the HTTP request's body in bytes. It
Christopher Fauletaf4dc4c2020-05-05 17:33:25 +020019227 will represent the advertised Content-Length header, or the size of the
19228 available data in case of chunked encoding.
Willy Tarreaua5910cc2015-05-02 00:46:08 +020019229
Willy Tarreau74ca5042013-06-11 23:12:07 +020019230req.cook([<name>]) : string
19231cook([<name>]) : string (deprecated)
19232 This extracts the last occurrence of the cookie name <name> on a "Cookie"
19233 header line from the request, and returns its value as string. If no name is
19234 specified, the first cookie value is returned. When used with ACLs, all
19235 matching cookies are evaluated. Spaces around the name and the value are
19236 ignored as requested by the Cookie header specification (RFC6265). The cookie
19237 name is case-sensitive. Empty cookies are valid, so an empty cookie may very
19238 well return an empty value if it is present. Use the "found" match to detect
19239 presence. Use the res.cook() variant for response cookies sent by the server.
19240
19241 ACL derivatives :
19242 cook([<name>]) : exact string match
19243 cook_beg([<name>]) : prefix match
19244 cook_dir([<name>]) : subdir match
19245 cook_dom([<name>]) : domain match
19246 cook_end([<name>]) : suffix match
19247 cook_len([<name>]) : length match
19248 cook_reg([<name>]) : regex match
19249 cook_sub([<name>]) : substring match
Willy Tarreaud63335a2010-02-26 12:56:52 +010019250
Willy Tarreau74ca5042013-06-11 23:12:07 +020019251req.cook_cnt([<name>]) : integer
19252cook_cnt([<name>]) : integer (deprecated)
19253 Returns an integer value representing the number of occurrences of the cookie
19254 <name> in the request, or all cookies if <name> is not specified.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019255
Willy Tarreau74ca5042013-06-11 23:12:07 +020019256req.cook_val([<name>]) : integer
19257cook_val([<name>]) : integer (deprecated)
19258 This extracts the last occurrence of the cookie name <name> on a "Cookie"
19259 header line from the request, and converts its value to an integer which is
19260 returned. If no name is specified, the first cookie value is returned. When
19261 used in ACLs, all matching names are iterated over until a value matches.
Willy Tarreau0e698542011-09-16 08:32:32 +020019262
Willy Tarreau74ca5042013-06-11 23:12:07 +020019263cookie([<name>]) : string (deprecated)
19264 This extracts the last occurrence of the cookie name <name> on a "Cookie"
19265 header line from the request, or a "Set-Cookie" header from the response, and
19266 returns its value as a string. A typical use is to get multiple clients
19267 sharing a same profile use the same server. This can be similar to what
Willy Tarreau294d0f02015-08-10 19:40:12 +020019268 "appsession" did with the "request-learn" statement, but with support for
Willy Tarreau74ca5042013-06-11 23:12:07 +020019269 multi-peer synchronization and state keeping across restarts. If no name is
19270 specified, the first cookie value is returned. This fetch should not be used
19271 anymore and should be replaced by req.cook() or res.cook() instead as it
19272 ambiguously uses the direction based on the context where it is used.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019273
Willy Tarreau74ca5042013-06-11 23:12:07 +020019274hdr([<name>[,<occ>]]) : string
19275 This is equivalent to req.hdr() when used on requests, and to res.hdr() when
19276 used on responses. Please refer to these respective fetches for more details.
19277 In case of doubt about the fetch direction, please use the explicit ones.
19278 Note that contrary to the hdr() sample fetch method, the hdr_* ACL keywords
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030019279 unambiguously apply to the request headers.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019280
Willy Tarreau74ca5042013-06-11 23:12:07 +020019281req.fhdr(<name>[,<occ>]) : string
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019282 This returns the full value of the last occurrence of header <name> in an
19283 HTTP request. It differs from req.hdr() in that any commas present in the
19284 value are returned and are not used as delimiters. This is sometimes useful
19285 with headers such as User-Agent.
19286
19287 When used from an ACL, all occurrences are iterated over until a match is
19288 found.
19289
Willy Tarreau74ca5042013-06-11 23:12:07 +020019290 Optionally, a specific occurrence might be specified as a position number.
19291 Positive values indicate a position from the first occurrence, with 1 being
19292 the first one. Negative values indicate positions relative to the last one,
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019293 with -1 being the last one.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019294
Willy Tarreau74ca5042013-06-11 23:12:07 +020019295req.fhdr_cnt([<name>]) : integer
19296 Returns an integer value representing the number of occurrences of request
19297 header field name <name>, or the total number of header fields if <name> is
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019298 not specified. Like req.fhdr() it differs from res.hdr_cnt() by not splitting
19299 headers at commas.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019300
Willy Tarreau74ca5042013-06-11 23:12:07 +020019301req.hdr([<name>[,<occ>]]) : string
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019302 This returns the last comma-separated value of the header <name> in an HTTP
19303 request. The fetch considers any comma as a delimiter for distinct values.
19304 This is useful if you need to process headers that are defined to be a list
19305 of values, such as Accept, or X-Forwarded-For. If full-line headers are
19306 desired instead, use req.fhdr(). Please carefully check RFC 7231 to know how
19307 certain headers are supposed to be parsed. Also, some of them are case
19308 insensitive (e.g. Connection).
19309
19310 When used from an ACL, all occurrences are iterated over until a match is
19311 found.
19312
Willy Tarreau74ca5042013-06-11 23:12:07 +020019313 Optionally, a specific occurrence might be specified as a position number.
19314 Positive values indicate a position from the first occurrence, with 1 being
19315 the first one. Negative values indicate positions relative to the last one,
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019316 with -1 being the last one.
19317
19318 A typical use is with the X-Forwarded-For header once converted to IP,
19319 associated with an IP stick-table.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019320
Willy Tarreau74ca5042013-06-11 23:12:07 +020019321 ACL derivatives :
19322 hdr([<name>[,<occ>]]) : exact string match
19323 hdr_beg([<name>[,<occ>]]) : prefix match
19324 hdr_dir([<name>[,<occ>]]) : subdir match
19325 hdr_dom([<name>[,<occ>]]) : domain match
19326 hdr_end([<name>[,<occ>]]) : suffix match
19327 hdr_len([<name>[,<occ>]]) : length match
19328 hdr_reg([<name>[,<occ>]]) : regex match
19329 hdr_sub([<name>[,<occ>]]) : substring match
19330
19331req.hdr_cnt([<name>]) : integer
19332hdr_cnt([<header>]) : integer (deprecated)
19333 Returns an integer value representing the number of occurrences of request
19334 header field name <name>, or the total number of header field values if
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019335 <name> is not specified. Like req.hdr() it counts each comma separated
19336 part of the header's value. If counting of full-line headers is desired,
19337 then req.fhdr_cnt() should be used instead.
19338
19339 With ACLs, it can be used to detect presence, absence or abuse of a specific
19340 header, as well as to block request smuggling attacks by rejecting requests
19341 which contain more than one of certain headers.
19342
19343 Refer to req.hdr() for more information on header matching.
Willy Tarreau74ca5042013-06-11 23:12:07 +020019344
19345req.hdr_ip([<name>[,<occ>]]) : ip
19346hdr_ip([<name>[,<occ>]]) : ip (deprecated)
19347 This extracts the last occurrence of header <name> in an HTTP request,
19348 converts it to an IPv4 or IPv6 address and returns this address. When used
19349 with ACLs, all occurrences are checked, and if <name> is omitted, every value
Willy Tarreau7b0e00d2021-03-25 14:12:29 +010019350 of every header is checked. The parser strictly adheres to the format
19351 described in RFC7239, with the extension that IPv4 addresses may optionally
19352 be followed by a colon (':') and a valid decimal port number (0 to 65535),
19353 which will be silently dropped. All other forms will not match and will
19354 cause the address to be ignored.
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019355
19356 The <occ> parameter is processed as with req.hdr().
19357
19358 A typical use is with the X-Forwarded-For and X-Client-IP headers.
Willy Tarreau74ca5042013-06-11 23:12:07 +020019359
19360req.hdr_val([<name>[,<occ>]]) : integer
19361hdr_val([<name>[,<occ>]]) : integer (deprecated)
19362 This extracts the last occurrence of header <name> in an HTTP request, and
19363 converts it to an integer value. When used with ACLs, all occurrences are
19364 checked, and if <name> is omitted, every value of every header is checked.
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019365
19366 The <occ> parameter is processed as with req.hdr().
19367
19368 A typical use is with the X-Forwarded-For header.
Willy Tarreau74ca5042013-06-11 23:12:07 +020019369
Christopher Faulet687a68e2020-11-24 17:13:24 +010019370req.hdrs : string
19371 Returns the current request headers as string including the last empty line
19372 separating headers from the request body. The last empty line can be used to
19373 detect a truncated header block. This sample fetch is useful for some SPOE
19374 headers analyzers and for advanced logging.
19375
19376req.hdrs_bin : binary
19377 Returns the current request headers contained in preparsed binary form. This
19378 is useful for offloading some processing with SPOE. Each string is described
19379 by a length followed by the number of bytes indicated in the length. The
19380 length is represented using the variable integer encoding detailed in the
19381 SPOE documentation. The end of the list is marked by a couple of empty header
19382 names and values (length of 0 for both).
19383
19384 *(<str:header-name><str:header-value>)<empty string><empty string>
Frédéric Lécailleec891192019-02-26 15:02:35 +010019385
Christopher Faulet687a68e2020-11-24 17:13:24 +010019386 int: refer to the SPOE documentation for the encoding
19387 str: <int:length><bytes>
Frédéric Lécailleec891192019-02-26 15:02:35 +010019388
Willy Tarreau74ca5042013-06-11 23:12:07 +020019389http_auth(<userlist>) : boolean
19390 Returns a boolean indicating whether the authentication data received from
19391 the client match a username & password stored in the specified userlist. This
19392 fetch function is not really useful outside of ACLs. Currently only http
19393 basic auth is supported.
19394
Thierry FOURNIER9eec0a62014-01-22 18:38:02 +010019395http_auth_group(<userlist>) : string
19396 Returns a string corresponding to the user name found in the authentication
19397 data received from the client if both the user name and password are valid
19398 according to the specified userlist. The main purpose is to use it in ACLs
19399 where it is then checked whether the user belongs to any group within a list.
Willy Tarreau74ca5042013-06-11 23:12:07 +020019400 This fetch function is not really useful outside of ACLs. Currently only http
19401 basic auth is supported.
19402
19403 ACL derivatives :
Thierry FOURNIER9eec0a62014-01-22 18:38:02 +010019404 http_auth_group(<userlist>) : group ...
19405 Returns true when the user extracted from the request and whose password is
19406 valid according to the specified userlist belongs to at least one of the
19407 groups.
Willy Tarreau74ca5042013-06-11 23:12:07 +020019408
Christopher Fauleta4063562019-08-02 11:51:37 +020019409http_auth_pass : string
Willy Tarreauc9c6cdb2020-03-05 16:03:58 +010019410 Returns the user's password found in the authentication data received from
19411 the client, as supplied in the Authorization header. Not checks are
19412 performed by this sample fetch. Only Basic authentication is supported.
Christopher Fauleta4063562019-08-02 11:51:37 +020019413
19414http_auth_type : string
Willy Tarreauc9c6cdb2020-03-05 16:03:58 +010019415 Returns the authentication method found in the authentication data received from
19416 the client, as supplied in the Authorization header. Not checks are
19417 performed by this sample fetch. Only Basic authentication is supported.
Christopher Fauleta4063562019-08-02 11:51:37 +020019418
19419http_auth_user : string
Willy Tarreauc9c6cdb2020-03-05 16:03:58 +010019420 Returns the user name found in the authentication data received from the
19421 client, as supplied in the Authorization header. Not checks are performed by
19422 this sample fetch. Only Basic authentication is supported.
Christopher Fauleta4063562019-08-02 11:51:37 +020019423
Willy Tarreau74ca5042013-06-11 23:12:07 +020019424http_first_req : boolean
Willy Tarreau7f18e522010-10-22 20:04:13 +020019425 Returns true when the request being processed is the first one of the
19426 connection. This can be used to add or remove headers that may be missing
Willy Tarreau74ca5042013-06-11 23:12:07 +020019427 from some requests when a request is not the first one, or to help grouping
19428 requests in the logs.
Willy Tarreau7f18e522010-10-22 20:04:13 +020019429
Willy Tarreau74ca5042013-06-11 23:12:07 +020019430method : integer + string
19431 Returns an integer value corresponding to the method in the HTTP request. For
19432 example, "GET" equals 1 (check sources to establish the matching). Value 9
19433 means "other method" and may be converted to a string extracted from the
19434 stream. This should not be used directly as a sample, this is only meant to
19435 be used from ACLs, which transparently convert methods from patterns to these
19436 integer + string values. Some predefined ACL already check for most common
19437 methods.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019438
Willy Tarreau74ca5042013-06-11 23:12:07 +020019439 ACL derivatives :
19440 method : case insensitive method match
Willy Tarreau6a06a402007-07-15 20:15:28 +020019441
Willy Tarreau74ca5042013-06-11 23:12:07 +020019442 Example :
19443 # only accept GET and HEAD requests
19444 acl valid_method method GET HEAD
19445 http-request deny if ! valid_method
Willy Tarreau6a06a402007-07-15 20:15:28 +020019446
Willy Tarreau74ca5042013-06-11 23:12:07 +020019447path : string
19448 This extracts the request's URL path, which starts at the first slash and
19449 ends before the question mark (without the host part). A typical use is with
19450 prefetch-capable caches, and with portals which need to aggregate multiple
19451 information from databases and keep them in caches. Note that with outgoing
19452 caches, it would be wiser to use "url" instead. With ACLs, it's typically
Davor Ocelice9ed2812017-12-25 17:49:28 +010019453 used to match exact file names (e.g. "/login.php"), or directory parts using
Willy Tarreau74ca5042013-06-11 23:12:07 +020019454 the derivative forms. See also the "url" and "base" fetch methods.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019455
Willy Tarreau74ca5042013-06-11 23:12:07 +020019456 ACL derivatives :
19457 path : exact string match
19458 path_beg : prefix match
19459 path_dir : subdir match
19460 path_dom : domain match
19461 path_end : suffix match
19462 path_len : length match
19463 path_reg : regex match
19464 path_sub : substring match
Willy Tarreau6a06a402007-07-15 20:15:28 +020019465
Christopher Faulete720c322020-09-02 17:25:18 +020019466pathq : string
19467 This extracts the request's URL path with the query-string, which starts at
19468 the first slash. This sample fetch is pretty handy to always retrieve a
19469 relative URI, excluding the scheme and the authority part, if any. Indeed,
19470 while it is the common representation for an HTTP/1.1 request target, in
19471 HTTP/2, an absolute URI is often used. This sample fetch will return the same
19472 result in both cases.
19473
Willy Tarreau49ad95c2015-01-19 15:06:26 +010019474query : string
19475 This extracts the request's query string, which starts after the first
19476 question mark. If no question mark is present, this fetch returns nothing. If
19477 a question mark is present but nothing follows, it returns an empty string.
19478 This means it's possible to easily know whether a query string is present
Tim Düsterhus4896c442016-11-29 02:15:19 +010019479 using the "found" matching method. This fetch is the complement of "path"
Willy Tarreau49ad95c2015-01-19 15:06:26 +010019480 which stops before the question mark.
19481
Willy Tarreaueb27ec72015-02-20 13:55:29 +010019482req.hdr_names([<delim>]) : string
19483 This builds a string made from the concatenation of all header names as they
19484 appear in the request when the rule is evaluated. The default delimiter is
19485 the comma (',') but it may be overridden as an optional argument <delim>. In
19486 this case, only the first character of <delim> is considered.
19487
Willy Tarreau74ca5042013-06-11 23:12:07 +020019488req.ver : string
19489req_ver : string (deprecated)
19490 Returns the version string from the HTTP request, for example "1.1". This can
19491 be useful for logs, but is mostly there for ACL. Some predefined ACL already
19492 check for versions 1.0 and 1.1.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019493
Willy Tarreau74ca5042013-06-11 23:12:07 +020019494 ACL derivatives :
19495 req_ver : exact string match
Willy Tarreau0e698542011-09-16 08:32:32 +020019496
Christopher Faulete596d182020-05-05 17:46:34 +020019497res.body : binary
19498 This returns the HTTP response's available body as a block of data. Unlike
19499 the request side, there is no directive to wait for the response's body. This
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019500 sample fetch is really useful (and usable) in the health-check context.
19501
19502 It may be used in tcp-check based expect rules.
Christopher Faulete596d182020-05-05 17:46:34 +020019503
19504res.body_len : integer
19505 This returns the length of the HTTP response available body in bytes. Unlike
19506 the request side, there is no directive to wait for the response's body. This
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019507 sample fetch is really useful (and usable) in the health-check context.
19508
19509 It may be used in tcp-check based expect rules.
Christopher Faulete596d182020-05-05 17:46:34 +020019510
19511res.body_size : integer
19512 This returns the advertised length of the HTTP response body in bytes. It
19513 will represent the advertised Content-Length header, or the size of the
19514 available data in case of chunked encoding. Unlike the request side, there is
19515 no directive to wait for the response body. This sample fetch is really
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019516 useful (and usable) in the health-check context.
19517
19518 It may be used in tcp-check based expect rules.
Christopher Faulete596d182020-05-05 17:46:34 +020019519
Remi Tricot-Le Bretonbf971212020-10-27 11:55:57 +010019520res.cache_hit : boolean
19521 Returns the boolean "true" value if the response has been built out of an
19522 HTTP cache entry, otherwise returns boolean "false".
19523
19524res.cache_name : string
19525 Returns a string containing the name of the HTTP cache that was used to
19526 build the HTTP response if res.cache_hit is true, otherwise returns an
19527 empty string.
19528
Willy Tarreau74ca5042013-06-11 23:12:07 +020019529res.comp : boolean
19530 Returns the boolean "true" value if the response has been compressed by
19531 HAProxy, otherwise returns boolean "false". This may be used to add
19532 information in the logs.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019533
Willy Tarreau74ca5042013-06-11 23:12:07 +020019534res.comp_algo : string
19535 Returns a string containing the name of the algorithm used if the response
19536 was compressed by HAProxy, for example : "deflate". This may be used to add
19537 some information in the logs.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019538
Willy Tarreau74ca5042013-06-11 23:12:07 +020019539res.cook([<name>]) : string
19540scook([<name>]) : string (deprecated)
19541 This extracts the last occurrence of the cookie name <name> on a "Set-Cookie"
19542 header line from the response, and returns its value as string. If no name is
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019543 specified, the first cookie value is returned.
19544
19545 It may be used in tcp-check based expect rules.
Willy Tarreau0ce3aa02012-04-25 18:46:33 +020019546
Willy Tarreau74ca5042013-06-11 23:12:07 +020019547 ACL derivatives :
19548 scook([<name>] : exact string match
Willy Tarreau0ce3aa02012-04-25 18:46:33 +020019549
Willy Tarreau74ca5042013-06-11 23:12:07 +020019550res.cook_cnt([<name>]) : integer
19551scook_cnt([<name>]) : integer (deprecated)
19552 Returns an integer value representing the number of occurrences of the cookie
19553 <name> in the response, or all cookies if <name> is not specified. This is
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019554 mostly useful when combined with ACLs to detect suspicious responses.
19555
19556 It may be used in tcp-check based expect rules.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019557
Willy Tarreau74ca5042013-06-11 23:12:07 +020019558res.cook_val([<name>]) : integer
19559scook_val([<name>]) : integer (deprecated)
19560 This extracts the last occurrence of the cookie name <name> on a "Set-Cookie"
19561 header line from the response, and converts its value to an integer which is
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019562 returned. If no name is specified, the first cookie value is returned.
19563
19564 It may be used in tcp-check based expect rules.
Willy Tarreaud63335a2010-02-26 12:56:52 +010019565
Willy Tarreau74ca5042013-06-11 23:12:07 +020019566res.fhdr([<name>[,<occ>]]) : string
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019567 This fetch works like the req.fhdr() fetch with the difference that it acts
19568 on the headers within an HTTP response.
19569
19570 Like req.fhdr() the res.fhdr() fetch returns full values. If the header is
19571 defined to be a list you should use res.hdr().
19572
19573 This fetch is sometimes useful with headers such as Date or Expires.
19574
19575 It may be used in tcp-check based expect rules.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019576
Willy Tarreau74ca5042013-06-11 23:12:07 +020019577res.fhdr_cnt([<name>]) : integer
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019578 This fetch works like the req.fhdr_cnt() fetch with the difference that it
19579 acts on the headers within an HTTP response.
19580
19581 Like req.fhdr_cnt() the res.fhdr_cnt() fetch acts on full values. If the
19582 header is defined to be a list you should use res.hdr_cnt().
19583
19584 It may be used in tcp-check based expect rules.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019585
Willy Tarreau74ca5042013-06-11 23:12:07 +020019586res.hdr([<name>[,<occ>]]) : string
19587shdr([<name>[,<occ>]]) : string (deprecated)
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019588 This fetch works like the req.hdr() fetch with the difference that it acts
19589 on the headers within an HTTP response.
19590
Ilya Shipitsinacf84592021-02-06 22:29:08 +050019591 Like req.hdr() the res.hdr() fetch considers the comma to be a delimiter. If
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019592 this is not desired res.fhdr() should be used.
19593
19594 It may be used in tcp-check based expect rules.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019595
Willy Tarreau74ca5042013-06-11 23:12:07 +020019596 ACL derivatives :
19597 shdr([<name>[,<occ>]]) : exact string match
19598 shdr_beg([<name>[,<occ>]]) : prefix match
19599 shdr_dir([<name>[,<occ>]]) : subdir match
19600 shdr_dom([<name>[,<occ>]]) : domain match
19601 shdr_end([<name>[,<occ>]]) : suffix match
19602 shdr_len([<name>[,<occ>]]) : length match
19603 shdr_reg([<name>[,<occ>]]) : regex match
19604 shdr_sub([<name>[,<occ>]]) : substring match
19605
19606res.hdr_cnt([<name>]) : integer
19607shdr_cnt([<name>]) : integer (deprecated)
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019608 This fetch works like the req.hdr_cnt() fetch with the difference that it
19609 acts on the headers within an HTTP response.
19610
19611 Like req.hdr_cnt() the res.hdr_cnt() fetch considers the comma to be a
Ilya Shipitsinacf84592021-02-06 22:29:08 +050019612 delimiter. If this is not desired res.fhdr_cnt() should be used.
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019613
19614 It may be used in tcp-check based expect rules.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019615
Willy Tarreau74ca5042013-06-11 23:12:07 +020019616res.hdr_ip([<name>[,<occ>]]) : ip
19617shdr_ip([<name>[,<occ>]]) : ip (deprecated)
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019618 This fetch works like the req.hdr_ip() fetch with the difference that it
19619 acts on the headers within an HTTP response.
19620
19621 This can be useful to learn some data into a stick table.
19622
19623 It may be used in tcp-check based expect rules.
Willy Tarreau6a06a402007-07-15 20:15:28 +020019624
Willy Tarreaueb27ec72015-02-20 13:55:29 +010019625res.hdr_names([<delim>]) : string
19626 This builds a string made from the concatenation of all header names as they
19627 appear in the response when the rule is evaluated. The default delimiter is
19628 the comma (',') but it may be overridden as an optional argument <delim>. In
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019629 this case, only the first character of <delim> is considered.
19630
19631 It may be used in tcp-check based expect rules.
Willy Tarreaueb27ec72015-02-20 13:55:29 +010019632
Willy Tarreau74ca5042013-06-11 23:12:07 +020019633res.hdr_val([<name>[,<occ>]]) : integer
19634shdr_val([<name>[,<occ>]]) : integer (deprecated)
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019635 This fetch works like the req.hdr_val() fetch with the difference that it
19636 acts on the headers within an HTTP response.
19637
19638 This can be useful to learn some data into a stick table.
19639
19640 It may be used in tcp-check based expect rules.
Christopher Faulete596d182020-05-05 17:46:34 +020019641
19642res.hdrs : string
19643 Returns the current response headers as string including the last empty line
19644 separating headers from the request body. The last empty line can be used to
19645 detect a truncated header block. This sample fetch is useful for some SPOE
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019646 headers analyzers and for advanced logging.
19647
19648 It may also be used in tcp-check based expect rules.
Christopher Faulete596d182020-05-05 17:46:34 +020019649
19650res.hdrs_bin : binary
19651 Returns the current response headers contained in preparsed binary form. This
19652 is useful for offloading some processing with SPOE. It may be used in
19653 tcp-check based expect rules. Each string is described by a length followed
19654 by the number of bytes indicated in the length. The length is represented
19655 using the variable integer encoding detailed in the SPOE documentation. The
19656 end of the list is marked by a couple of empty header names and values
19657 (length of 0 for both).
19658
19659 *(<str:header-name><str:header-value>)<empty string><empty string>
19660
19661 int: refer to the SPOE documentation for the encoding
19662 str: <int:length><bytes>
Alexandre Cassen5eb1a902007-11-29 15:43:32 +010019663
Willy Tarreau74ca5042013-06-11 23:12:07 +020019664res.ver : string
19665resp_ver : string (deprecated)
19666 Returns the version string from the HTTP response, for example "1.1". This
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019667 can be useful for logs, but is mostly there for ACL.
19668
19669 It may be used in tcp-check based expect rules.
Willy Tarreau0e698542011-09-16 08:32:32 +020019670
Willy Tarreau74ca5042013-06-11 23:12:07 +020019671 ACL derivatives :
19672 resp_ver : exact string match
Alexandre Cassen5eb1a902007-11-29 15:43:32 +010019673
Willy Tarreau74ca5042013-06-11 23:12:07 +020019674set-cookie([<name>]) : string (deprecated)
19675 This extracts the last occurrence of the cookie name <name> on a "Set-Cookie"
19676 header line from the response and uses the corresponding value to match. This
Willy Tarreau294d0f02015-08-10 19:40:12 +020019677 can be comparable to what "appsession" did with default options, but with
Willy Tarreau74ca5042013-06-11 23:12:07 +020019678 support for multi-peer synchronization and state keeping across restarts.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +010019679
Willy Tarreau74ca5042013-06-11 23:12:07 +020019680 This fetch function is deprecated and has been superseded by the "res.cook"
19681 fetch. This keyword will disappear soon.
Krzysztof Piotr Oledzki6b35ce12010-02-01 23:35:44 +010019682
Willy Tarreau74ca5042013-06-11 23:12:07 +020019683status : integer
19684 Returns an integer containing the HTTP status code in the HTTP response, for
19685 example, 302. It is mostly used within ACLs and integer ranges, for example,
Tim Duesterhus27c70ae2021-01-23 17:50:21 +010019686 to remove any Location header if the response is not a 3xx.
19687
19688 It may be used in tcp-check based expect rules.
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019689
Thierry Fournier0e00dca2016-04-07 15:47:40 +020019690unique-id : string
19691 Returns the unique-id attached to the request. The directive
19692 "unique-id-format" must be set. If it is not set, the unique-id sample fetch
19693 fails. Note that the unique-id is usually used with HTTP requests, however this
19694 sample fetch can be used with other protocols. Obviously, if it is used with
19695 other protocols than HTTP, the unique-id-format directive must not contain
19696 HTTP parts. See: unique-id-format and unique-id-header
19697
Willy Tarreau74ca5042013-06-11 23:12:07 +020019698url : string
19699 This extracts the request's URL as presented in the request. A typical use is
19700 with prefetch-capable caches, and with portals which need to aggregate
19701 multiple information from databases and keep them in caches. With ACLs, using
19702 "path" is preferred over using "url", because clients may send a full URL as
19703 is normally done with proxies. The only real use is to match "*" which does
19704 not match in "path", and for which there is already a predefined ACL. See
19705 also "path" and "base".
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019706
Willy Tarreau74ca5042013-06-11 23:12:07 +020019707 ACL derivatives :
19708 url : exact string match
19709 url_beg : prefix match
19710 url_dir : subdir match
19711 url_dom : domain match
19712 url_end : suffix match
19713 url_len : length match
19714 url_reg : regex match
19715 url_sub : substring match
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019716
Willy Tarreau74ca5042013-06-11 23:12:07 +020019717url_ip : ip
19718 This extracts the IP address from the request's URL when the host part is
19719 presented as an IP address. Its use is very limited. For instance, a
19720 monitoring system might use this field as an alternative for the source IP in
19721 order to test what path a given source address would follow, or to force an
19722 entry in a table for a given source address. With ACLs it can be used to
19723 restrict access to certain systems through a proxy, for example when combined
19724 with option "http_proxy".
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019725
Willy Tarreau74ca5042013-06-11 23:12:07 +020019726url_port : integer
19727 This extracts the port part from the request's URL. Note that if the port is
19728 not specified in the request, port 80 is assumed. With ACLs it can be used to
19729 restrict access to certain systems through a proxy, for example when combined
19730 with option "http_proxy".
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019731
Willy Tarreau1ede1da2015-05-07 16:06:18 +020019732urlp([<name>[,<delim>]]) : string
19733url_param([<name>[,<delim>]]) : string
Willy Tarreau74ca5042013-06-11 23:12:07 +020019734 This extracts the first occurrence of the parameter <name> in the query
19735 string, which begins after either '?' or <delim>, and which ends before '&',
Willy Tarreau1ede1da2015-05-07 16:06:18 +020019736 ';' or <delim>. The parameter name is case-sensitive. If no name is given,
19737 any parameter will match, and the first one will be returned. The result is
19738 a string corresponding to the value of the parameter <name> as presented in
19739 the request (no URL decoding is performed). This can be used for session
Willy Tarreau74ca5042013-06-11 23:12:07 +020019740 stickiness based on a client ID, to extract an application cookie passed as a
19741 URL parameter, or in ACLs to apply some checks. Note that the ACL version of
Willy Tarreau1ede1da2015-05-07 16:06:18 +020019742 this fetch iterates over multiple parameters and will iteratively report all
19743 parameters values if no name is given
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019744
Willy Tarreau74ca5042013-06-11 23:12:07 +020019745 ACL derivatives :
19746 urlp(<name>[,<delim>]) : exact string match
19747 urlp_beg(<name>[,<delim>]) : prefix match
19748 urlp_dir(<name>[,<delim>]) : subdir match
19749 urlp_dom(<name>[,<delim>]) : domain match
19750 urlp_end(<name>[,<delim>]) : suffix match
19751 urlp_len(<name>[,<delim>]) : length match
19752 urlp_reg(<name>[,<delim>]) : regex match
19753 urlp_sub(<name>[,<delim>]) : substring match
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019754
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019755
Willy Tarreau74ca5042013-06-11 23:12:07 +020019756 Example :
19757 # match http://example.com/foo?PHPSESSIONID=some_id
19758 stick on urlp(PHPSESSIONID)
19759 # match http://example.com/foo;JSESSIONID=some_id
19760 stick on urlp(JSESSIONID,;)
Willy Tarreau25c1ebc2012-04-25 16:21:44 +020019761
Jarno Huuskonen676f6222017-03-30 09:19:45 +030019762urlp_val([<name>[,<delim>]]) : integer
Willy Tarreau74ca5042013-06-11 23:12:07 +020019763 See "urlp" above. This one extracts the URL parameter <name> in the request
19764 and converts it to an integer value. This can be used for session stickiness
19765 based on a user ID for example, or with ACLs to match a page number or price.
Willy Tarreaua9fddca2012-07-31 07:51:48 +020019766
Dragan Dosen0070cd52016-06-16 12:19:49 +020019767url32 : integer
19768 This returns a 32-bit hash of the value obtained by concatenating the first
19769 Host header and the whole URL including parameters (not only the path part of
19770 the request, as in the "base32" fetch above). This is useful to track per-URL
19771 activity. A shorter hash is stored, saving a lot of memory. The output type
19772 is an unsigned integer.
19773
19774url32+src : binary
19775 This returns the concatenation of the "url32" fetch and the "src" fetch. The
19776 resulting type is of type binary, with a size of 8 or 20 bytes depending on
19777 the source address family. This can be used to track per-IP, per-URL counters.
19778
Christopher Faulet16032ab2020-04-30 11:30:00 +020019779
Christopher Faulete596d182020-05-05 17:46:34 +0200197807.3.7. Fetching samples for developers
Christopher Fauletd47941d2020-01-08 14:40:19 +010019781---------------------------------------
19782
19783This set of sample fetch methods is reserved to developers and must never be
19784used on a production environment, except on developer demand, for debugging
19785purposes. Moreover, no special care will be taken on backwards compatibility.
19786There is no warranty the following sample fetches will never change, be renamed
19787or simply removed. So be really careful if you should use one of them. To avoid
19788any ambiguity, these sample fetches are placed in the dedicated scope "internal",
19789for instance "internal.strm.is_htx".
19790
19791internal.htx.data : integer
19792 Returns the size in bytes used by data in the HTX message associated to a
19793 channel. The channel is chosen depending on the sample direction.
19794
19795internal.htx.free : integer
19796 Returns the free space (size - used) in bytes in the HTX message associated
19797 to a channel. The channel is chosen depending on the sample direction.
19798
19799internal.htx.free_data : integer
19800 Returns the free space for the data in bytes in the HTX message associated to
19801 a channel. The channel is chosen depending on the sample direction.
19802
19803internal.htx.has_eom : boolean
Christopher Fauletd1ac2b92020-12-02 19:12:22 +010019804 Returns true if the HTX message associated to a channel contains the
19805 end-of-message flag (EOM). Otherwise, it returns false. The channel is chosen
19806 depending on the sample direction.
Christopher Fauletd47941d2020-01-08 14:40:19 +010019807
19808internal.htx.nbblks : integer
19809 Returns the number of blocks present in the HTX message associated to a
19810 channel. The channel is chosen depending on the sample direction.
19811
19812internal.htx.size : integer
19813 Returns the total size in bytes of the HTX message associated to a
19814 channel. The channel is chosen depending on the sample direction.
19815
19816internal.htx.used : integer
19817 Returns the total size used in bytes (data + metadata) in the HTX message
19818 associated to a channel. The channel is chosen depending on the sample
19819 direction.
19820
19821internal.htx_blk.size(<idx>) : integer
19822 Returns the size of the block at the position <idx> in the HTX message
19823 associated to a channel or 0 if it does not exist. The channel is chosen
19824 depending on the sample direction. <idx> may be any positive integer or one
19825 of the special value :
19826 * head : The oldest inserted block
19827 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019828 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019829
19830internal.htx_blk.type(<idx>) : string
19831 Returns the type of the block at the position <idx> in the HTX message
19832 associated to a channel or "HTX_BLK_UNUSED" if it does not exist. The channel
19833 is chosen depending on the sample direction. <idx> may be any positive
19834 integer or one of the special value :
19835 * head : The oldest inserted block
19836 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019837 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019838
19839internal.htx_blk.data(<idx>) : binary
19840 Returns the value of the DATA block at the position <idx> in the HTX message
19841 associated to a channel or an empty string if it does not exist or if it is
19842 not a DATA block. The channel is chosen depending on the sample direction.
19843 <idx> may be any positive integer or one of the special value :
19844
19845 * head : The oldest inserted block
19846 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019847 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019848
19849internal.htx_blk.hdrname(<idx>) : string
19850 Returns the header name of the HEADER block at the position <idx> in the HTX
19851 message associated to a channel or an empty string if it does not exist or if
19852 it is not an HEADER block. The channel is chosen depending on the sample
19853 direction. <idx> may be any positive integer or one of the special value :
19854
19855 * head : The oldest inserted block
19856 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019857 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019858
19859internal.htx_blk.hdrval(<idx>) : string
19860 Returns the header value of the HEADER block at the position <idx> in the HTX
19861 message associated to a channel or an empty string if it does not exist or if
19862 it is not an HEADER block. The channel is chosen depending on the sample
19863 direction. <idx> may be any positive integer or one of the special value :
19864
19865 * head : The oldest inserted block
19866 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019867 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019868
19869internal.htx_blk.start_line(<idx>) : string
19870 Returns the value of the REQ_SL or RES_SL block at the position <idx> in the
19871 HTX message associated to a channel or an empty string if it does not exist
19872 or if it is not a SL block. The channel is chosen depending on the sample
19873 direction. <idx> may be any positive integer or one of the special value :
19874
19875 * head : The oldest inserted block
19876 * tail : The newest inserted block
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050019877 * first : The first block where to (re)start the analysis
Christopher Fauletd47941d2020-01-08 14:40:19 +010019878
19879internal.strm.is_htx : boolean
19880 Returns true if the current stream is an HTX stream. It means the data in the
19881 channels buffers are stored using the internal HTX representation. Otherwise,
19882 it returns false.
19883
19884
Willy Tarreau74ca5042013-06-11 23:12:07 +0200198857.4. Pre-defined ACLs
Willy Tarreauc57f0e22009-05-10 13:12:33 +020019886---------------------
Willy Tarreauced27012008-01-17 20:35:34 +010019887
Willy Tarreauc57f0e22009-05-10 13:12:33 +020019888Some predefined ACLs are hard-coded so that they do not have to be declared in
19889every frontend which needs them. They all have their names in upper case in
Patrick Mézard2382ad62010-05-09 10:43:32 +020019890order to avoid confusion. Their equivalence is provided below.
Willy Tarreauced27012008-01-17 20:35:34 +010019891
Willy Tarreauc57f0e22009-05-10 13:12:33 +020019892ACL name Equivalent to Usage
Christopher Faulet779184e2021-04-01 17:24:04 +020019893---------------+----------------------------------+------------------------------------------------------
19894FALSE always_false never match
19895HTTP req.proto_http match if request protocol is valid HTTP
19896HTTP_1.0 req.ver 1.0 match if HTTP request version is 1.0
19897HTTP_1.1 req.ver 1.1 match if HTTP request version is 1.1
Christopher Faulet8043e832021-03-26 16:00:54 +010019898HTTP_2.0 req.ver 2.0 match if HTTP request version is 2.0
Christopher Faulet779184e2021-04-01 17:24:04 +020019899HTTP_CONTENT req.hdr_val(content-length) gt 0 match an existing content-length in the HTTP request
19900HTTP_URL_ABS url_reg ^[^/:]*:// match absolute URL with scheme
19901HTTP_URL_SLASH url_beg / match URL beginning with "/"
19902HTTP_URL_STAR url * match URL equal to "*"
19903LOCALHOST src 127.0.0.1/8 match connection from local host
19904METH_CONNECT method CONNECT match HTTP CONNECT method
19905METH_DELETE method DELETE match HTTP DELETE method
19906METH_GET method GET HEAD match HTTP GET or HEAD method
19907METH_HEAD method HEAD match HTTP HEAD method
19908METH_OPTIONS method OPTIONS match HTTP OPTIONS method
19909METH_POST method POST match HTTP POST method
19910METH_PUT method PUT match HTTP PUT method
19911METH_TRACE method TRACE match HTTP TRACE method
19912RDP_COOKIE req.rdp_cookie_cnt gt 0 match presence of an RDP cookie in the request buffer
19913REQ_CONTENT req.len gt 0 match data in the request buffer
19914TRUE always_true always match
19915WAIT_END wait_end wait for end of content analysis
19916---------------+----------------------------------+------------------------------------------------------
Willy Tarreauced27012008-01-17 20:35:34 +010019917
Willy Tarreaub937b7e2010-01-12 15:27:54 +010019918
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200199198. Logging
19920----------
Willy Tarreau844e3c52008-01-11 16:28:18 +010019921
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019922One of HAProxy's strong points certainly lies is its precise logs. It probably
19923provides the finest level of information available for such a product, which is
19924very important for troubleshooting complex environments. Standard information
19925provided in logs include client ports, TCP/HTTP state timers, precise session
19926state at termination and precise termination cause, information about decisions
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010019927to direct traffic to a server, and of course the ability to capture arbitrary
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019928headers.
19929
19930In order to improve administrators reactivity, it offers a great transparency
19931about encountered problems, both internal and external, and it is possible to
19932send logs to different sources at the same time with different level filters :
19933
19934 - global process-level logs (system errors, start/stop, etc..)
19935 - per-instance system and internal errors (lack of resource, bugs, ...)
19936 - per-instance external troubles (servers up/down, max connections)
19937 - per-instance activity (client connections), either at the establishment or
19938 at the termination.
Davor Ocelice9ed2812017-12-25 17:49:28 +010019939 - per-request control of log-level, e.g.
Jim Freeman9e8714b2015-05-26 09:16:34 -060019940 http-request set-log-level silent if sensitive_request
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019941
19942The ability to distribute different levels of logs to different log servers
19943allow several production teams to interact and to fix their problems as soon
19944as possible. For example, the system team might monitor system-wide errors,
19945while the application team might be monitoring the up/down for their servers in
19946real time, and the security team might analyze the activity logs with one hour
19947delay.
19948
19949
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200199508.1. Log levels
19951---------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019952
Simon Hormandf791f52011-05-29 15:01:10 +090019953TCP and HTTP connections can be logged with information such as the date, time,
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019954source IP address, destination address, connection duration, response times,
Simon Hormandf791f52011-05-29 15:01:10 +090019955HTTP request, HTTP return code, number of bytes transmitted, conditions
19956in which the session ended, and even exchanged cookies values. For example
19957track a particular user's problems. All messages may be sent to up to two
19958syslog servers. Check the "log" keyword in section 4.2 for more information
19959about log facilities.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019960
19961
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200199628.2. Log formats
19963----------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019964
William Lallemand48940402012-01-30 16:47:22 +010019965HAProxy supports 5 log formats. Several fields are common between these formats
Simon Hormandf791f52011-05-29 15:01:10 +090019966and will be detailed in the following sections. A few of them may vary
19967slightly with the configuration, due to indicators specific to certain
19968options. The supported formats are as follows :
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019969
19970 - the default format, which is very basic and very rarely used. It only
19971 provides very basic information about the incoming connection at the moment
19972 it is accepted : source IP:port, destination IP:port, and frontend-name.
19973 This mode will eventually disappear so it will not be described to great
19974 extents.
19975
19976 - the TCP format, which is more advanced. This format is enabled when "option
19977 tcplog" is set on the frontend. HAProxy will then usually wait for the
19978 connection to terminate before logging. This format provides much richer
19979 information, such as timers, connection counts, queue size, etc... This
19980 format is recommended for pure TCP proxies.
19981
19982 - the HTTP format, which is the most advanced for HTTP proxying. This format
19983 is enabled when "option httplog" is set on the frontend. It provides the
19984 same information as the TCP format with some HTTP-specific fields such as
19985 the request, the status code, and captures of headers and cookies. This
19986 format is recommended for HTTP proxies.
19987
Emeric Brun3a058f32009-06-30 18:26:00 +020019988 - the CLF HTTP format, which is equivalent to the HTTP format, but with the
19989 fields arranged in the same order as the CLF format. In this mode, all
19990 timers, captures, flags, etc... appear one per field after the end of the
19991 common fields, in the same order they appear in the standard HTTP format.
19992
William Lallemand48940402012-01-30 16:47:22 +010019993 - the custom log format, allows you to make your own log line.
19994
Willy Tarreaucc6c8912009-02-22 10:53:55 +010019995Next sections will go deeper into details for each of these formats. Format
19996specification will be performed on a "field" basis. Unless stated otherwise, a
19997field is a portion of text delimited by any number of spaces. Since syslog
19998servers are susceptible of inserting fields at the beginning of a line, it is
19999always assumed that the first field is the one containing the process name and
20000identifier.
20001
20002Note : Since log lines may be quite long, the log examples in sections below
20003 might be broken into multiple lines. The example log lines will be
20004 prefixed with 3 closing angle brackets ('>>>') and each time a log is
20005 broken into multiple lines, each non-final line will end with a
20006 backslash ('\') and the next line will start indented by two characters.
20007
20008
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200200098.2.1. Default log format
20010-------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020011
20012This format is used when no specific option is set. The log is emitted as soon
20013as the connection is accepted. One should note that this currently is the only
20014format which logs the request's destination IP and ports.
20015
20016 Example :
20017 listen www
20018 mode http
20019 log global
20020 server srv1 127.0.0.1:8000
20021
20022 >>> Feb 6 12:12:09 localhost \
20023 haproxy[14385]: Connect from 10.0.1.2:33312 to 10.0.3.31:8012 \
20024 (www/HTTP)
20025
20026 Field Format Extract from the example above
20027 1 process_name '[' pid ']:' haproxy[14385]:
20028 2 'Connect from' Connect from
20029 3 source_ip ':' source_port 10.0.1.2:33312
20030 4 'to' to
20031 5 destination_ip ':' destination_port 10.0.3.31:8012
20032 6 '(' frontend_name '/' mode ')' (www/HTTP)
20033
20034Detailed fields description :
20035 - "source_ip" is the IP address of the client which initiated the connection.
20036 - "source_port" is the TCP port of the client which initiated the connection.
20037 - "destination_ip" is the IP address the client connected to.
20038 - "destination_port" is the TCP port the client connected to.
20039 - "frontend_name" is the name of the frontend (or listener) which received
20040 and processed the connection.
20041 - "mode is the mode the frontend is operating (TCP or HTTP).
20042
Willy Tarreauceb24bc2010-11-09 12:46:41 +010020043In case of a UNIX socket, the source and destination addresses are marked as
20044"unix:" and the ports reflect the internal ID of the socket which accepted the
20045connection (the same ID as reported in the stats).
20046
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020047It is advised not to use this deprecated format for newer installations as it
20048will eventually disappear.
20049
20050
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200200518.2.2. TCP log format
20052---------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020053
20054The TCP format is used when "option tcplog" is specified in the frontend, and
20055is the recommended format for pure TCP proxies. It provides a lot of precious
20056information for troubleshooting. Since this format includes timers and byte
20057counts, the log is normally emitted at the end of the session. It can be
20058emitted earlier if "option logasap" is specified, which makes sense in most
20059environments with long sessions such as remote terminals. Sessions which match
20060the "monitor" rules are never logged. It is also possible not to emit logs for
20061sessions for which no data were exchanged between the client and the server, by
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +020020062specifying "option dontlognull" in the frontend. Successful connections will
20063not be logged if "option dontlog-normal" is specified in the frontend. A few
20064fields may slightly vary depending on some configuration options, those are
20065marked with a star ('*') after the field name below.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020066
20067 Example :
20068 frontend fnt
20069 mode tcp
20070 option tcplog
20071 log global
20072 default_backend bck
20073
20074 backend bck
20075 server srv1 127.0.0.1:8000
20076
20077 >>> Feb 6 12:12:56 localhost \
20078 haproxy[14387]: 10.0.1.2:33313 [06/Feb/2009:12:12:51.443] fnt \
20079 bck/srv1 0/0/5007 212 -- 0/0/0/0/3 0/0
20080
20081 Field Format Extract from the example above
20082 1 process_name '[' pid ']:' haproxy[14387]:
20083 2 client_ip ':' client_port 10.0.1.2:33313
20084 3 '[' accept_date ']' [06/Feb/2009:12:12:51.443]
20085 4 frontend_name fnt
20086 5 backend_name '/' server_name bck/srv1
20087 6 Tw '/' Tc '/' Tt* 0/0/5007
20088 7 bytes_read* 212
20089 8 termination_state --
20090 9 actconn '/' feconn '/' beconn '/' srv_conn '/' retries* 0/0/0/0/3
20091 10 srv_queue '/' backend_queue 0/0
20092
20093Detailed fields description :
20094 - "client_ip" is the IP address of the client which initiated the TCP
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020095 connection to HAProxy. If the connection was accepted on a UNIX socket
Willy Tarreauceb24bc2010-11-09 12:46:41 +010020096 instead, the IP address would be replaced with the word "unix". Note that
20097 when the connection is accepted on a socket configured with "accept-proxy"
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010020098 and the PROXY protocol is correctly used, or with a "accept-netscaler-cip"
Davor Ocelice9ed2812017-12-25 17:49:28 +010020099 and the NetScaler Client IP insertion protocol is correctly used, then the
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010020100 logs will reflect the forwarded connection's information.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020101
20102 - "client_port" is the TCP port of the client which initiated the connection.
Willy Tarreauceb24bc2010-11-09 12:46:41 +010020103 If the connection was accepted on a UNIX socket instead, the port would be
20104 replaced with the ID of the accepting socket, which is also reported in the
20105 stats interface.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020106
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020107 - "accept_date" is the exact date when the connection was received by HAProxy
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020108 (which might be very slightly different from the date observed on the
20109 network if there was some queuing in the system's backlog). This is usually
Willy Tarreau590a0512018-09-05 11:56:48 +020020110 the same date which may appear in any upstream firewall's log. When used in
20111 HTTP mode, the accept_date field will be reset to the first moment the
20112 connection is ready to receive a new request (end of previous response for
20113 HTTP/1, immediately after previous request for HTTP/2).
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020114
20115 - "frontend_name" is the name of the frontend (or listener) which received
20116 and processed the connection.
20117
20118 - "backend_name" is the name of the backend (or listener) which was selected
20119 to manage the connection to the server. This will be the same as the
20120 frontend if no switching rule has been applied, which is common for TCP
20121 applications.
20122
20123 - "server_name" is the name of the last server to which the connection was
20124 sent, which might differ from the first one if there were connection errors
20125 and a redispatch occurred. Note that this server belongs to the backend
20126 which processed the request. If the connection was aborted before reaching
20127 a server, "<NOSRV>" is indicated instead of a server name.
20128
20129 - "Tw" is the total time in milliseconds spent waiting in the various queues.
20130 It can be "-1" if the connection was aborted before reaching the queue.
20131 See "Timers" below for more details.
20132
20133 - "Tc" is the total time in milliseconds spent waiting for the connection to
20134 establish to the final server, including retries. It can be "-1" if the
20135 connection was aborted before a connection could be established. See
20136 "Timers" below for more details.
20137
20138 - "Tt" is the total time in milliseconds elapsed between the accept and the
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030020139 last close. It covers all possible processing. There is one exception, if
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020140 "option logasap" was specified, then the time counting stops at the moment
20141 the log is emitted. In this case, a '+' sign is prepended before the value,
20142 indicating that the final one will be larger. See "Timers" below for more
20143 details.
20144
20145 - "bytes_read" is the total number of bytes transmitted from the server to
20146 the client when the log is emitted. If "option logasap" is specified, the
20147 this value will be prefixed with a '+' sign indicating that the final one
20148 may be larger. Please note that this value is a 64-bit counter, so log
20149 analysis tools must be able to handle it without overflowing.
20150
20151 - "termination_state" is the condition the session was in when the session
20152 ended. This indicates the session state, which side caused the end of
20153 session to happen, and for what reason (timeout, error, ...). The normal
20154 flags should be "--", indicating the session was closed by either end with
20155 no data remaining in buffers. See below "Session state at disconnection"
20156 for more details.
20157
20158 - "actconn" is the total number of concurrent connections on the process when
Jamie Gloudonaaa21002012-08-25 00:18:33 -040020159 the session was logged. It is useful to detect when some per-process system
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020160 limits have been reached. For instance, if actconn is close to 512 when
20161 multiple connection errors occur, chances are high that the system limits
20162 the process to use a maximum of 1024 file descriptors and that all of them
Willy Tarreauc57f0e22009-05-10 13:12:33 +020020163 are used. See section 3 "Global parameters" to find how to tune the system.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020164
20165 - "feconn" is the total number of concurrent connections on the frontend when
20166 the session was logged. It is useful to estimate the amount of resource
20167 required to sustain high loads, and to detect when the frontend's "maxconn"
20168 has been reached. Most often when this value increases by huge jumps, it is
20169 because there is congestion on the backend servers, but sometimes it can be
20170 caused by a denial of service attack.
20171
20172 - "beconn" is the total number of concurrent connections handled by the
20173 backend when the session was logged. It includes the total number of
20174 concurrent connections active on servers as well as the number of
20175 connections pending in queues. It is useful to estimate the amount of
20176 additional servers needed to support high loads for a given application.
20177 Most often when this value increases by huge jumps, it is because there is
20178 congestion on the backend servers, but sometimes it can be caused by a
20179 denial of service attack.
20180
20181 - "srv_conn" is the total number of concurrent connections still active on
20182 the server when the session was logged. It can never exceed the server's
20183 configured "maxconn" parameter. If this value is very often close or equal
20184 to the server's "maxconn", it means that traffic regulation is involved a
20185 lot, meaning that either the server's maxconn value is too low, or that
20186 there aren't enough servers to process the load with an optimal response
20187 time. When only one of the server's "srv_conn" is high, it usually means
20188 that this server has some trouble causing the connections to take longer to
20189 be processed than on other servers.
20190
20191 - "retries" is the number of connection retries experienced by this session
20192 when trying to connect to the server. It must normally be zero, unless a
20193 server is being stopped at the same moment the connection was attempted.
20194 Frequent retries generally indicate either a network problem between
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020195 HAProxy and the server, or a misconfigured system backlog on the server
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020196 preventing new connections from being queued. This field may optionally be
20197 prefixed with a '+' sign, indicating that the session has experienced a
20198 redispatch after the maximal retry count has been reached on the initial
20199 server. In this case, the server name appearing in the log is the one the
20200 connection was redispatched to, and not the first one, though both may
20201 sometimes be the same in case of hashing for instance. So as a general rule
20202 of thumb, when a '+' is present in front of the retry count, this count
20203 should not be attributed to the logged server.
20204
20205 - "srv_queue" is the total number of requests which were processed before
20206 this one in the server queue. It is zero when the request has not gone
20207 through the server queue. It makes it possible to estimate the approximate
20208 server's response time by dividing the time spent in queue by the number of
20209 requests in the queue. It is worth noting that if a session experiences a
20210 redispatch and passes through two server queues, their positions will be
Davor Ocelice9ed2812017-12-25 17:49:28 +010020211 cumulative. A request should not pass through both the server queue and the
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020212 backend queue unless a redispatch occurs.
20213
20214 - "backend_queue" is the total number of requests which were processed before
20215 this one in the backend's global queue. It is zero when the request has not
20216 gone through the global queue. It makes it possible to estimate the average
20217 queue length, which easily translates into a number of missing servers when
20218 divided by a server's "maxconn" parameter. It is worth noting that if a
20219 session experiences a redispatch, it may pass twice in the backend's queue,
Davor Ocelice9ed2812017-12-25 17:49:28 +010020220 and then both positions will be cumulative. A request should not pass
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020221 through both the server queue and the backend queue unless a redispatch
20222 occurs.
20223
20224
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200202258.2.3. HTTP log format
20226----------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020227
20228The HTTP format is the most complete and the best suited for HTTP proxies. It
20229is enabled by when "option httplog" is specified in the frontend. It provides
20230the same level of information as the TCP format with additional features which
20231are specific to the HTTP protocol. Just like the TCP format, the log is usually
20232emitted at the end of the session, unless "option logasap" is specified, which
20233generally only makes sense for download sites. A session which matches the
20234"monitor" rules will never logged. It is also possible not to log sessions for
20235which no data were sent by the client by specifying "option dontlognull" in the
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +020020236frontend. Successful connections will not be logged if "option dontlog-normal"
20237is specified in the frontend.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020238
20239Most fields are shared with the TCP log, some being different. A few fields may
20240slightly vary depending on some configuration options. Those ones are marked
20241with a star ('*') after the field name below.
20242
20243 Example :
20244 frontend http-in
20245 mode http
20246 option httplog
20247 log global
20248 default_backend bck
20249
20250 backend static
20251 server srv1 127.0.0.1:8000
20252
20253 >>> Feb 6 12:14:14 localhost \
20254 haproxy[14389]: 10.0.1.2:33317 [06/Feb/2009:12:14:14.655] http-in \
20255 static/srv1 10/0/30/69/109 200 2750 - - ---- 1/1/1/1/0 0/0 {1wt.eu} \
Willy Tarreaud72758d2010-01-12 10:42:19 +010020256 {} "GET /index.html HTTP/1.1"
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020257
20258 Field Format Extract from the example above
20259 1 process_name '[' pid ']:' haproxy[14389]:
20260 2 client_ip ':' client_port 10.0.1.2:33317
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020261 3 '[' request_date ']' [06/Feb/2009:12:14:14.655]
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020262 4 frontend_name http-in
20263 5 backend_name '/' server_name static/srv1
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020264 6 TR '/' Tw '/' Tc '/' Tr '/' Ta* 10/0/30/69/109
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020265 7 status_code 200
20266 8 bytes_read* 2750
20267 9 captured_request_cookie -
20268 10 captured_response_cookie -
20269 11 termination_state ----
20270 12 actconn '/' feconn '/' beconn '/' srv_conn '/' retries* 1/1/1/1/0
20271 13 srv_queue '/' backend_queue 0/0
20272 14 '{' captured_request_headers* '}' {haproxy.1wt.eu}
20273 15 '{' captured_response_headers* '}' {}
20274 16 '"' http_request '"' "GET /index.html HTTP/1.1"
Willy Tarreaud72758d2010-01-12 10:42:19 +010020275
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020276Detailed fields description :
20277 - "client_ip" is the IP address of the client which initiated the TCP
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020278 connection to HAProxy. If the connection was accepted on a UNIX socket
Willy Tarreauceb24bc2010-11-09 12:46:41 +010020279 instead, the IP address would be replaced with the word "unix". Note that
20280 when the connection is accepted on a socket configured with "accept-proxy"
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010020281 and the PROXY protocol is correctly used, or with a "accept-netscaler-cip"
Davor Ocelice9ed2812017-12-25 17:49:28 +010020282 and the NetScaler Client IP insertion protocol is correctly used, then the
Bertrand Jacquin93b227d2016-06-04 15:11:10 +010020283 logs will reflect the forwarded connection's information.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020284
20285 - "client_port" is the TCP port of the client which initiated the connection.
Willy Tarreauceb24bc2010-11-09 12:46:41 +010020286 If the connection was accepted on a UNIX socket instead, the port would be
20287 replaced with the ID of the accepting socket, which is also reported in the
20288 stats interface.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020289
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020290 - "request_date" is the exact date when the first byte of the HTTP request
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020291 was received by HAProxy (log field %tr).
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020292
20293 - "frontend_name" is the name of the frontend (or listener) which received
20294 and processed the connection.
20295
20296 - "backend_name" is the name of the backend (or listener) which was selected
20297 to manage the connection to the server. This will be the same as the
20298 frontend if no switching rule has been applied.
20299
20300 - "server_name" is the name of the last server to which the connection was
20301 sent, which might differ from the first one if there were connection errors
20302 and a redispatch occurred. Note that this server belongs to the backend
20303 which processed the request. If the request was aborted before reaching a
20304 server, "<NOSRV>" is indicated instead of a server name. If the request was
20305 intercepted by the stats subsystem, "<STATS>" is indicated instead.
20306
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020307 - "TR" is the total time in milliseconds spent waiting for a full HTTP
20308 request from the client (not counting body) after the first byte was
20309 received. It can be "-1" if the connection was aborted before a complete
John Roeslerfb2fce12019-07-10 15:45:51 -050020310 request could be received or a bad request was received. It should
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020311 always be very small because a request generally fits in one single packet.
20312 Large times here generally indicate network issues between the client and
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020313 HAProxy or requests being typed by hand. See section 8.4 "Timing Events"
Willy Tarreau590a0512018-09-05 11:56:48 +020020314 for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020315
20316 - "Tw" is the total time in milliseconds spent waiting in the various queues.
20317 It can be "-1" if the connection was aborted before reaching the queue.
Willy Tarreau590a0512018-09-05 11:56:48 +020020318 See section 8.4 "Timing Events" for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020319
20320 - "Tc" is the total time in milliseconds spent waiting for the connection to
20321 establish to the final server, including retries. It can be "-1" if the
Willy Tarreau590a0512018-09-05 11:56:48 +020020322 request was aborted before a connection could be established. See section
20323 8.4 "Timing Events" for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020324
20325 - "Tr" is the total time in milliseconds spent waiting for the server to send
20326 a full HTTP response, not counting data. It can be "-1" if the request was
20327 aborted before a complete response could be received. It generally matches
20328 the server's processing time for the request, though it may be altered by
20329 the amount of data sent by the client to the server. Large times here on
Willy Tarreau590a0512018-09-05 11:56:48 +020020330 "GET" requests generally indicate an overloaded server. See section 8.4
20331 "Timing Events" for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020332
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020333 - "Ta" is the time the request remained active in HAProxy, which is the total
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020334 time in milliseconds elapsed between the first byte of the request was
20335 received and the last byte of response was sent. It covers all possible
20336 processing except the handshake (see Th) and idle time (see Ti). There is
20337 one exception, if "option logasap" was specified, then the time counting
20338 stops at the moment the log is emitted. In this case, a '+' sign is
20339 prepended before the value, indicating that the final one will be larger.
Willy Tarreau590a0512018-09-05 11:56:48 +020020340 See section 8.4 "Timing Events" for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020341
20342 - "status_code" is the HTTP status code returned to the client. This status
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020343 is generally set by the server, but it might also be set by HAProxy when
20344 the server cannot be reached or when its response is blocked by HAProxy.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020345
20346 - "bytes_read" is the total number of bytes transmitted to the client when
20347 the log is emitted. This does include HTTP headers. If "option logasap" is
John Roeslerfb2fce12019-07-10 15:45:51 -050020348 specified, this value will be prefixed with a '+' sign indicating that
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020349 the final one may be larger. Please note that this value is a 64-bit
20350 counter, so log analysis tools must be able to handle it without
20351 overflowing.
20352
20353 - "captured_request_cookie" is an optional "name=value" entry indicating that
20354 the client had this cookie in the request. The cookie name and its maximum
20355 length are defined by the "capture cookie" statement in the frontend
20356 configuration. The field is a single dash ('-') when the option is not
20357 set. Only one cookie may be captured, it is generally used to track session
20358 ID exchanges between a client and a server to detect session crossing
20359 between clients due to application bugs. For more details, please consult
20360 the section "Capturing HTTP headers and cookies" below.
20361
20362 - "captured_response_cookie" is an optional "name=value" entry indicating
20363 that the server has returned a cookie with its response. The cookie name
20364 and its maximum length are defined by the "capture cookie" statement in the
20365 frontend configuration. The field is a single dash ('-') when the option is
20366 not set. Only one cookie may be captured, it is generally used to track
20367 session ID exchanges between a client and a server to detect session
20368 crossing between clients due to application bugs. For more details, please
20369 consult the section "Capturing HTTP headers and cookies" below.
20370
20371 - "termination_state" is the condition the session was in when the session
20372 ended. This indicates the session state, which side caused the end of
20373 session to happen, for what reason (timeout, error, ...), just like in TCP
20374 logs, and information about persistence operations on cookies in the last
20375 two characters. The normal flags should begin with "--", indicating the
20376 session was closed by either end with no data remaining in buffers. See
20377 below "Session state at disconnection" for more details.
20378
20379 - "actconn" is the total number of concurrent connections on the process when
Jamie Gloudonaaa21002012-08-25 00:18:33 -040020380 the session was logged. It is useful to detect when some per-process system
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020381 limits have been reached. For instance, if actconn is close to 512 or 1024
20382 when multiple connection errors occur, chances are high that the system
20383 limits the process to use a maximum of 1024 file descriptors and that all
Willy Tarreauc57f0e22009-05-10 13:12:33 +020020384 of them are used. See section 3 "Global parameters" to find how to tune the
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020385 system.
20386
20387 - "feconn" is the total number of concurrent connections on the frontend when
20388 the session was logged. It is useful to estimate the amount of resource
20389 required to sustain high loads, and to detect when the frontend's "maxconn"
20390 has been reached. Most often when this value increases by huge jumps, it is
20391 because there is congestion on the backend servers, but sometimes it can be
20392 caused by a denial of service attack.
20393
20394 - "beconn" is the total number of concurrent connections handled by the
20395 backend when the session was logged. It includes the total number of
20396 concurrent connections active on servers as well as the number of
20397 connections pending in queues. It is useful to estimate the amount of
20398 additional servers needed to support high loads for a given application.
20399 Most often when this value increases by huge jumps, it is because there is
20400 congestion on the backend servers, but sometimes it can be caused by a
20401 denial of service attack.
20402
20403 - "srv_conn" is the total number of concurrent connections still active on
20404 the server when the session was logged. It can never exceed the server's
20405 configured "maxconn" parameter. If this value is very often close or equal
20406 to the server's "maxconn", it means that traffic regulation is involved a
20407 lot, meaning that either the server's maxconn value is too low, or that
20408 there aren't enough servers to process the load with an optimal response
20409 time. When only one of the server's "srv_conn" is high, it usually means
20410 that this server has some trouble causing the requests to take longer to be
20411 processed than on other servers.
20412
20413 - "retries" is the number of connection retries experienced by this session
20414 when trying to connect to the server. It must normally be zero, unless a
20415 server is being stopped at the same moment the connection was attempted.
20416 Frequent retries generally indicate either a network problem between
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020417 HAProxy and the server, or a misconfigured system backlog on the server
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020418 preventing new connections from being queued. This field may optionally be
20419 prefixed with a '+' sign, indicating that the session has experienced a
20420 redispatch after the maximal retry count has been reached on the initial
20421 server. In this case, the server name appearing in the log is the one the
20422 connection was redispatched to, and not the first one, though both may
20423 sometimes be the same in case of hashing for instance. So as a general rule
20424 of thumb, when a '+' is present in front of the retry count, this count
20425 should not be attributed to the logged server.
20426
20427 - "srv_queue" is the total number of requests which were processed before
20428 this one in the server queue. It is zero when the request has not gone
20429 through the server queue. It makes it possible to estimate the approximate
20430 server's response time by dividing the time spent in queue by the number of
20431 requests in the queue. It is worth noting that if a session experiences a
20432 redispatch and passes through two server queues, their positions will be
Davor Ocelice9ed2812017-12-25 17:49:28 +010020433 cumulative. A request should not pass through both the server queue and the
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020434 backend queue unless a redispatch occurs.
20435
20436 - "backend_queue" is the total number of requests which were processed before
20437 this one in the backend's global queue. It is zero when the request has not
20438 gone through the global queue. It makes it possible to estimate the average
20439 queue length, which easily translates into a number of missing servers when
20440 divided by a server's "maxconn" parameter. It is worth noting that if a
20441 session experiences a redispatch, it may pass twice in the backend's queue,
Davor Ocelice9ed2812017-12-25 17:49:28 +010020442 and then both positions will be cumulative. A request should not pass
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020443 through both the server queue and the backend queue unless a redispatch
20444 occurs.
20445
20446 - "captured_request_headers" is a list of headers captured in the request due
20447 to the presence of the "capture request header" statement in the frontend.
20448 Multiple headers can be captured, they will be delimited by a vertical bar
20449 ('|'). When no capture is enabled, the braces do not appear, causing a
20450 shift of remaining fields. It is important to note that this field may
20451 contain spaces, and that using it requires a smarter log parser than when
20452 it's not used. Please consult the section "Capturing HTTP headers and
20453 cookies" below for more details.
20454
20455 - "captured_response_headers" is a list of headers captured in the response
20456 due to the presence of the "capture response header" statement in the
20457 frontend. Multiple headers can be captured, they will be delimited by a
20458 vertical bar ('|'). When no capture is enabled, the braces do not appear,
20459 causing a shift of remaining fields. It is important to note that this
20460 field may contain spaces, and that using it requires a smarter log parser
20461 than when it's not used. Please consult the section "Capturing HTTP headers
20462 and cookies" below for more details.
20463
20464 - "http_request" is the complete HTTP request line, including the method,
20465 request and HTTP version string. Non-printable characters are encoded (see
20466 below the section "Non-printable characters"). This is always the last
20467 field, and it is always delimited by quotes and is the only one which can
20468 contain quotes. If new fields are added to the log format, they will be
20469 added before this field. This field might be truncated if the request is
20470 huge and does not fit in the standard syslog buffer (1024 characters). This
20471 is the reason why this field must always remain the last one.
20472
20473
Cyril Bontédc4d9032012-04-08 21:57:39 +0200204748.2.4. Custom log format
20475------------------------
William Lallemand48940402012-01-30 16:47:22 +010020476
Willy Tarreau2beef582012-12-20 17:22:52 +010020477The directive log-format allows you to customize the logs in http mode and tcp
William Lallemandbddd4fd2012-02-27 11:23:10 +010020478mode. It takes a string as argument.
William Lallemand48940402012-01-30 16:47:22 +010020479
Davor Ocelice9ed2812017-12-25 17:49:28 +010020480HAProxy understands some log format variables. % precedes log format variables.
William Lallemand48940402012-01-30 16:47:22 +010020481Variables can take arguments using braces ('{}'), and multiple arguments are
20482separated by commas within the braces. Flags may be added or removed by
20483prefixing them with a '+' or '-' sign.
20484
20485Special variable "%o" may be used to propagate its flags to all other
20486variables on the same format string. This is particularly handy with quoted
Dragan Dosen835b9212016-02-12 13:23:03 +010020487("Q") and escaped ("E") string formats.
William Lallemand48940402012-01-30 16:47:22 +010020488
Willy Tarreauc8368452012-12-21 00:09:23 +010020489If a variable is named between square brackets ('[' .. ']') then it is used
Willy Tarreaube722a22014-06-13 16:31:59 +020020490as a sample expression rule (see section 7.3). This it useful to add some
Willy Tarreauc8368452012-12-21 00:09:23 +010020491less common information such as the client's SSL certificate's DN, or to log
20492the key that would be used to store an entry into a stick table.
20493
Dragan Dosen1e3b16f2020-06-23 18:16:44 +020020494Note: spaces must be escaped. In configuration directives "log-format",
20495"log-format-sd" and "unique-id-format", spaces are considered as
20496delimiters and are merged. In order to emit a verbatim '%', it must be
20497preceded by another '%' resulting in '%%'.
William Lallemand48940402012-01-30 16:47:22 +010020498
Dragan Dosen835b9212016-02-12 13:23:03 +010020499Note: when using the RFC5424 syslog message format, the characters '"',
20500'\' and ']' inside PARAM-VALUE should be escaped with '\' as prefix (see
20501https://tools.ietf.org/html/rfc5424#section-6.3.3 for more details). In
20502such cases, the use of the flag "E" should be considered.
20503
William Lallemand48940402012-01-30 16:47:22 +010020504Flags are :
20505 * Q: quote a string
Jamie Gloudonaaa21002012-08-25 00:18:33 -040020506 * X: hexadecimal representation (IPs, Ports, %Ts, %rt, %pid)
Dragan Dosen835b9212016-02-12 13:23:03 +010020507 * E: escape characters '"', '\' and ']' in a string with '\' as prefix
20508 (intended purpose is for the RFC5424 structured-data log formats)
William Lallemand48940402012-01-30 16:47:22 +010020509
20510 Example:
20511
20512 log-format %T\ %t\ Some\ Text
20513 log-format %{+Q}o\ %t\ %s\ %{-Q}r
20514
Dragan Dosen835b9212016-02-12 13:23:03 +010020515 log-format-sd %{+Q,+E}o\ [exampleSDID@1234\ header=%[capture.req.hdr(0)]]
20516
William Lallemand48940402012-01-30 16:47:22 +010020517At the moment, the default HTTP format is defined this way :
20518
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020519 log-format "%ci:%cp [%tr] %ft %b/%s %TR/%Tw/%Tc/%Tr/%Ta %ST %B %CC \
20520 %CS %tsc %ac/%fc/%bc/%sc/%rc %sq/%bq %hr %hs %{+Q}r"
William Lallemand48940402012-01-30 16:47:22 +010020521
William Lallemandbddd4fd2012-02-27 11:23:10 +010020522the default CLF format is defined this way :
William Lallemand48940402012-01-30 16:47:22 +010020523
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020524 log-format "%{+Q}o %{-Q}ci - - [%trg] %r %ST %B \"\" \"\" %cp \
20525 %ms %ft %b %s %TR %Tw %Tc %Tr %Ta %tsc %ac %fc \
20526 %bc %sc %rc %sq %bq %CC %CS %hrl %hsl"
William Lallemand48940402012-01-30 16:47:22 +010020527
William Lallemandbddd4fd2012-02-27 11:23:10 +010020528and the default TCP format is defined this way :
20529
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020530 log-format "%ci:%cp [%t] %ft %b/%s %Tw/%Tc/%Tt %B %ts \
20531 %ac/%fc/%bc/%sc/%rc %sq/%bq"
William Lallemandbddd4fd2012-02-27 11:23:10 +010020532
William Lallemand48940402012-01-30 16:47:22 +010020533Please refer to the table below for currently defined variables :
20534
William Lallemandbddd4fd2012-02-27 11:23:10 +010020535 +---+------+-----------------------------------------------+-------------+
Willy Tarreauffc3fcd2012-10-12 20:17:54 +020020536 | R | var | field name (8.2.2 and 8.2.3 for description) | type |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020537 +---+------+-----------------------------------------------+-------------+
20538 | | %o | special variable, apply flags on all next var | |
20539 +---+------+-----------------------------------------------+-------------+
Willy Tarreau2beef582012-12-20 17:22:52 +010020540 | | %B | bytes_read (from server to client) | numeric |
20541 | H | %CC | captured_request_cookie | string |
20542 | H | %CS | captured_response_cookie | string |
William Lallemand5f232402012-04-05 18:02:55 +020020543 | | %H | hostname | string |
Andrew Hayworth0ebc55f2015-04-27 21:37:03 +000020544 | H | %HM | HTTP method (ex: POST) | string |
Maciej Zdeb21acc332020-11-26 10:45:52 +000020545 | H | %HP | HTTP request URI without query string | string |
Maciej Zdebfcdfd852020-11-30 18:27:47 +000020546 | H | %HPO | HTTP path only (without host nor query string)| string |
Andrew Hayworthe63ac872015-07-31 16:14:16 +000020547 | H | %HQ | HTTP request URI query string (ex: ?bar=baz) | string |
Andrew Hayworth0ebc55f2015-04-27 21:37:03 +000020548 | H | %HU | HTTP request URI (ex: /foo?bar=baz) | string |
20549 | H | %HV | HTTP version (ex: HTTP/1.0) | string |
William Lallemanda73203e2012-03-12 12:48:57 +010020550 | | %ID | unique-id | string |
Willy Tarreau4bf99632014-06-13 12:21:40 +020020551 | | %ST | status_code | numeric |
William Lallemand5f232402012-04-05 18:02:55 +020020552 | | %T | gmt_date_time | date |
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020553 | | %Ta | Active time of the request (from TR to end) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020554 | | %Tc | Tc | numeric |
Willy Tarreau27b639d2016-05-17 17:55:27 +020020555 | | %Td | Td = Tt - (Tq + Tw + Tc + Tr) | numeric |
Yuxans Yao4e25b012012-10-19 10:36:09 +080020556 | | %Tl | local_date_time | date |
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020557 | | %Th | connection handshake time (SSL, PROXY proto) | numeric |
20558 | H | %Ti | idle time before the HTTP request | numeric |
20559 | H | %Tq | Th + Ti + TR | numeric |
20560 | H | %TR | time to receive the full request from 1st byte| numeric |
20561 | H | %Tr | Tr (response time) | numeric |
William Lallemand5f232402012-04-05 18:02:55 +020020562 | | %Ts | timestamp | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020563 | | %Tt | Tt | numeric |
Damien Claisse57c8eb92020-04-28 12:09:19 +000020564 | | %Tu | Tu | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020565 | | %Tw | Tw | numeric |
Willy Tarreau2beef582012-12-20 17:22:52 +010020566 | | %U | bytes_uploaded (from client to server) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020567 | | %ac | actconn | numeric |
20568 | | %b | backend_name | string |
Willy Tarreau2beef582012-12-20 17:22:52 +010020569 | | %bc | beconn (backend concurrent connections) | numeric |
20570 | | %bi | backend_source_ip (connecting address) | IP |
20571 | | %bp | backend_source_port (connecting address) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020572 | | %bq | backend_queue | numeric |
Willy Tarreau2beef582012-12-20 17:22:52 +010020573 | | %ci | client_ip (accepted address) | IP |
20574 | | %cp | client_port (accepted address) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020575 | | %f | frontend_name | string |
Willy Tarreau2beef582012-12-20 17:22:52 +010020576 | | %fc | feconn (frontend concurrent connections) | numeric |
20577 | | %fi | frontend_ip (accepting address) | IP |
20578 | | %fp | frontend_port (accepting address) | numeric |
Willy Tarreau773d65f2012-10-12 14:56:11 +020020579 | | %ft | frontend_name_transport ('~' suffix for SSL) | string |
Willy Tarreau7346acb2014-08-28 15:03:15 +020020580 | | %lc | frontend_log_counter | numeric |
Willy Tarreaud9ed3d22014-06-13 12:23:06 +020020581 | | %hr | captured_request_headers default style | string |
20582 | | %hrl | captured_request_headers CLF style | string list |
20583 | | %hs | captured_response_headers default style | string |
20584 | | %hsl | captured_response_headers CLF style | string list |
Willy Tarreau812c88e2015-08-09 10:56:35 +020020585 | | %ms | accept date milliseconds (left-padded with 0) | numeric |
William Lallemand5f232402012-04-05 18:02:55 +020020586 | | %pid | PID | numeric |
Willy Tarreauffc3fcd2012-10-12 20:17:54 +020020587 | H | %r | http_request | string |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020588 | | %rc | retries | numeric |
Willy Tarreau1f0da242014-01-25 11:01:50 +010020589 | | %rt | request_counter (HTTP req or TCP session) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020590 | | %s | server_name | string |
Willy Tarreau2beef582012-12-20 17:22:52 +010020591 | | %sc | srv_conn (server concurrent connections) | numeric |
20592 | | %si | server_IP (target address) | IP |
20593 | | %sp | server_port (target address) | numeric |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020594 | | %sq | srv_queue | numeric |
Willy Tarreauffc3fcd2012-10-12 20:17:54 +020020595 | S | %sslc| ssl_ciphers (ex: AES-SHA) | string |
20596 | S | %sslv| ssl_version (ex: TLSv1) | string |
Willy Tarreau2beef582012-12-20 17:22:52 +010020597 | | %t | date_time (with millisecond resolution) | date |
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020598 | H | %tr | date_time of HTTP request | date |
20599 | H | %trg | gmt_date_time of start of HTTP request | date |
Jens Bissinger15c64ff2018-08-23 14:11:27 +020020600 | H | %trl | local_date_time of start of HTTP request | date |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020601 | | %ts | termination_state | string |
Willy Tarreauffc3fcd2012-10-12 20:17:54 +020020602 | H | %tsc | termination_state with cookie status | string |
William Lallemandbddd4fd2012-02-27 11:23:10 +010020603 +---+------+-----------------------------------------------+-------------+
William Lallemand48940402012-01-30 16:47:22 +010020604
Willy Tarreauffc3fcd2012-10-12 20:17:54 +020020605 R = Restrictions : H = mode http only ; S = SSL only
William Lallemand48940402012-01-30 16:47:22 +010020606
Willy Tarreau5f51e1a2012-12-03 18:40:10 +010020607
206088.2.5. Error log format
20609-----------------------
20610
20611When an incoming connection fails due to an SSL handshake or an invalid PROXY
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020612protocol header, HAProxy will log the event using a shorter, fixed line format.
Willy Tarreau5f51e1a2012-12-03 18:40:10 +010020613By default, logs are emitted at the LOG_INFO level, unless the option
20614"log-separate-errors" is set in the backend, in which case the LOG_ERR level
Davor Ocelice9ed2812017-12-25 17:49:28 +010020615will be used. Connections on which no data are exchanged (e.g. probes) are not
Willy Tarreau5f51e1a2012-12-03 18:40:10 +010020616logged if the "dontlognull" option is set.
20617
20618The format looks like this :
20619
20620 >>> Dec 3 18:27:14 localhost \
20621 haproxy[6103]: 127.0.0.1:56059 [03/Dec/2012:17:35:10.380] frt/f1: \
20622 Connection error during SSL handshake
20623
20624 Field Format Extract from the example above
20625 1 process_name '[' pid ']:' haproxy[6103]:
20626 2 client_ip ':' client_port 127.0.0.1:56059
20627 3 '[' accept_date ']' [03/Dec/2012:17:35:10.380]
20628 4 frontend_name "/" bind_name ":" frt/f1:
20629 5 message Connection error during SSL handshake
20630
20631These fields just provide minimal information to help debugging connection
20632failures.
20633
20634
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200206358.3. Advanced logging options
20636-----------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020637
20638Some advanced logging options are often looked for but are not easy to find out
20639just by looking at the various options. Here is an entry point for the few
20640options which can enable better logging. Please refer to the keywords reference
20641for more information about their usage.
20642
20643
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200206448.3.1. Disabling logging of external tests
20645------------------------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020646
20647It is quite common to have some monitoring tools perform health checks on
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020648HAProxy. Sometimes it will be a layer 3 load-balancer such as LVS or any
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020649commercial load-balancer, and sometimes it will simply be a more complete
20650monitoring system such as Nagios. When the tests are very frequent, users often
20651ask how to disable logging for those checks. There are three possibilities :
20652
20653 - if connections come from everywhere and are just TCP probes, it is often
20654 desired to simply disable logging of connections without data exchange, by
20655 setting "option dontlognull" in the frontend. It also disables logging of
20656 port scans, which may or may not be desired.
20657
Willy Tarreau9e9919d2020-10-14 15:55:23 +020020658 - it is possible to use the "http-request set-log-level silent" action using
20659 a variety of conditions (source networks, paths, user-agents, etc).
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020660
20661 - if the tests are performed on a known URI, use "monitor-uri" to declare
20662 this URI as dedicated to monitoring. Any host sending this request will
20663 only get the result of a health-check, and the request will not be logged.
20664
20665
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200206668.3.2. Logging before waiting for the session to terminate
20667----------------------------------------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020668
20669The problem with logging at end of connection is that you have no clue about
20670what is happening during very long sessions, such as remote terminal sessions
20671or large file downloads. This problem can be worked around by specifying
Davor Ocelice9ed2812017-12-25 17:49:28 +010020672"option logasap" in the frontend. HAProxy will then log as soon as possible,
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020673just before data transfer begins. This means that in case of TCP, it will still
20674log the connection status to the server, and in case of HTTP, it will log just
20675after processing the server headers. In this case, the number of bytes reported
20676is the number of header bytes sent to the client. In order to avoid confusion
20677with normal logs, the total time field and the number of bytes are prefixed
20678with a '+' sign which means that real numbers are certainly larger.
20679
20680
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200206818.3.3. Raising log level upon errors
20682------------------------------------
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +020020683
20684Sometimes it is more convenient to separate normal traffic from errors logs,
20685for instance in order to ease error monitoring from log files. When the option
20686"log-separate-errors" is used, connections which experience errors, timeouts,
20687retries, redispatches or HTTP status codes 5xx will see their syslog level
20688raised from "info" to "err". This will help a syslog daemon store the log in
20689a separate file. It is very important to keep the errors in the normal traffic
20690file too, so that log ordering is not altered. You should also be careful if
20691you already have configured your syslog daemon to store all logs higher than
20692"notice" in an "admin" file, because the "err" level is higher than "notice".
20693
20694
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200206958.3.4. Disabling logging of successful connections
20696--------------------------------------------------
Willy Tarreauc9bd0cc2009-05-10 11:57:02 +020020697
20698Although this may sound strange at first, some large sites have to deal with
20699multiple thousands of logs per second and are experiencing difficulties keeping
20700them intact for a long time or detecting errors within them. If the option
20701"dontlog-normal" is set on the frontend, all normal connections will not be
20702logged. In this regard, a normal connection is defined as one without any
20703error, timeout, retry nor redispatch. In HTTP, the status code is checked too,
20704and a response with a status 5xx is not considered normal and will be logged
20705too. Of course, doing is is really discouraged as it will remove most of the
20706useful information from the logs. Do this only if you have no other
20707alternative.
20708
20709
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200207108.4. Timing events
20711------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020712
20713Timers provide a great help in troubleshooting network problems. All values are
20714reported in milliseconds (ms). These timers should be used in conjunction with
20715the session termination flags. In TCP mode with "option tcplog" set on the
20716frontend, 3 control points are reported under the form "Tw/Tc/Tt", and in HTTP
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020717mode, 5 control points are reported under the form "TR/Tw/Tc/Tr/Ta". In
20718addition, three other measures are provided, "Th", "Ti", and "Tq".
20719
Guillaume de Lafondf27cddc2016-12-23 17:32:43 +010020720Timings events in HTTP mode:
20721
20722 first request 2nd request
20723 |<-------------------------------->|<-------------- ...
20724 t tr t tr ...
20725 ---|----|----|----|----|----|----|----|----|--
20726 : Th Ti TR Tw Tc Tr Td : Ti ...
20727 :<---- Tq ---->: :
20728 :<-------------- Tt -------------->:
Damien Claisse57c8eb92020-04-28 12:09:19 +000020729 :<-- -----Tu--------------->:
Guillaume de Lafondf27cddc2016-12-23 17:32:43 +010020730 :<--------- Ta --------->:
20731
20732Timings events in TCP mode:
20733
20734 TCP session
20735 |<----------------->|
20736 t t
20737 ---|----|----|----|----|---
20738 | Th Tw Tc Td |
20739 |<------ Tt ------->|
20740
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020741 - Th: total time to accept tcp connection and execute handshakes for low level
Davor Ocelice9ed2812017-12-25 17:49:28 +010020742 protocols. Currently, these protocols are proxy-protocol and SSL. This may
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020743 only happen once during the whole connection's lifetime. A large time here
20744 may indicate that the client only pre-established the connection without
20745 speaking, that it is experiencing network issues preventing it from
Davor Ocelice9ed2812017-12-25 17:49:28 +010020746 completing a handshake in a reasonable time (e.g. MTU issues), or that an
Willy Tarreau590a0512018-09-05 11:56:48 +020020747 SSL handshake was very expensive to compute. Please note that this time is
20748 reported only before the first request, so it is safe to average it over
20749 all request to calculate the amortized value. The second and subsequent
20750 request will always report zero here.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020751
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020752 - Ti: is the idle time before the HTTP request (HTTP mode only). This timer
20753 counts between the end of the handshakes and the first byte of the HTTP
20754 request. When dealing with a second request in keep-alive mode, it starts
Willy Tarreau590a0512018-09-05 11:56:48 +020020755 to count after the end of the transmission the previous response. When a
20756 multiplexed protocol such as HTTP/2 is used, it starts to count immediately
20757 after the previous request. Some browsers pre-establish connections to a
20758 server in order to reduce the latency of a future request, and keep them
20759 pending until they need it. This delay will be reported as the idle time. A
20760 value of -1 indicates that nothing was received on the connection.
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020761
20762 - TR: total time to get the client request (HTTP mode only). It's the time
20763 elapsed between the first bytes received and the moment the proxy received
20764 the empty line marking the end of the HTTP headers. The value "-1"
20765 indicates that the end of headers has never been seen. This happens when
20766 the client closes prematurely or times out. This time is usually very short
20767 since most requests fit in a single packet. A large time may indicate a
20768 request typed by hand during a test.
20769
20770 - Tq: total time to get the client request from the accept date or since the
20771 emission of the last byte of the previous response (HTTP mode only). It's
Davor Ocelice9ed2812017-12-25 17:49:28 +010020772 exactly equal to Th + Ti + TR unless any of them is -1, in which case it
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020773 returns -1 as well. This timer used to be very useful before the arrival of
20774 HTTP keep-alive and browsers' pre-connect feature. It's recommended to drop
20775 it in favor of TR nowadays, as the idle time adds a lot of noise to the
20776 reports.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020777
20778 - Tw: total time spent in the queues waiting for a connection slot. It
20779 accounts for backend queue as well as the server queues, and depends on the
20780 queue size, and the time needed for the server to complete previous
20781 requests. The value "-1" means that the request was killed before reaching
20782 the queue, which is generally what happens with invalid or denied requests.
20783
20784 - Tc: total time to establish the TCP connection to the server. It's the time
20785 elapsed between the moment the proxy sent the connection request, and the
20786 moment it was acknowledged by the server, or between the TCP SYN packet and
20787 the matching SYN/ACK packet in return. The value "-1" means that the
20788 connection never established.
20789
20790 - Tr: server response time (HTTP mode only). It's the time elapsed between
20791 the moment the TCP connection was established to the server and the moment
20792 the server sent its complete response headers. It purely shows its request
20793 processing time, without the network overhead due to the data transmission.
20794 It is worth noting that when the client has data to send to the server, for
20795 instance during a POST request, the time already runs, and this can distort
20796 apparent response time. For this reason, it's generally wise not to trust
20797 too much this field for POST requests initiated from clients behind an
20798 untrusted network. A value of "-1" here means that the last the response
20799 header (empty line) was never seen, most likely because the server timeout
20800 stroke before the server managed to process the request.
20801
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020802 - Ta: total active time for the HTTP request, between the moment the proxy
20803 received the first byte of the request header and the emission of the last
20804 byte of the response body. The exception is when the "logasap" option is
20805 specified. In this case, it only equals (TR+Tw+Tc+Tr), and is prefixed with
20806 a '+' sign. From this field, we can deduce "Td", the data transmission time,
20807 by subtracting other timers when valid :
20808
20809 Td = Ta - (TR + Tw + Tc + Tr)
20810
20811 Timers with "-1" values have to be excluded from this equation. Note that
20812 "Ta" can never be negative.
20813
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020814 - Tt: total session duration time, between the moment the proxy accepted it
20815 and the moment both ends were closed. The exception is when the "logasap"
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020816 option is specified. In this case, it only equals (Th+Ti+TR+Tw+Tc+Tr), and
20817 is prefixed with a '+' sign. From this field, we can deduce "Td", the data
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030020818 transmission time, by subtracting other timers when valid :
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020819
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020820 Td = Tt - (Th + Ti + TR + Tw + Tc + Tr)
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020821
20822 Timers with "-1" values have to be excluded from this equation. In TCP
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020823 mode, "Ti", "Tq" and "Tr" have to be excluded too. Note that "Tt" can never
20824 be negative and that for HTTP, Tt is simply equal to (Th+Ti+Ta).
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020825
Damien Claisse57c8eb92020-04-28 12:09:19 +000020826 - Tu: total estimated time as seen from client, between the moment the proxy
20827 accepted it and the moment both ends were closed, without idle time.
20828 This is useful to roughly measure end-to-end time as a user would see it,
20829 without idle time pollution from keep-alive time between requests. This
20830 timer in only an estimation of time seen by user as it assumes network
20831 latency is the same in both directions. The exception is when the "logasap"
20832 option is specified. In this case, it only equals (Th+TR+Tw+Tc+Tr), and is
20833 prefixed with a '+' sign.
20834
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020835These timers provide precious indications on trouble causes. Since the TCP
20836protocol defines retransmit delays of 3, 6, 12... seconds, we know for sure
20837that timers close to multiples of 3s are nearly always related to lost packets
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020838due to network problems (wires, negotiation, congestion). Moreover, if "Ta" or
20839"Tt" is close to a timeout value specified in the configuration, it often means
20840that a session has been aborted on timeout.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020841
20842Most common cases :
20843
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020844 - If "Th" or "Ti" are close to 3000, a packet has probably been lost between
20845 the client and the proxy. This is very rare on local networks but might
20846 happen when clients are on far remote networks and send large requests. It
20847 may happen that values larger than usual appear here without any network
20848 cause. Sometimes, during an attack or just after a resource starvation has
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020849 ended, HAProxy may accept thousands of connections in a few milliseconds.
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020850 The time spent accepting these connections will inevitably slightly delay
20851 processing of other connections, and it can happen that request times in the
20852 order of a few tens of milliseconds are measured after a few thousands of
20853 new connections have been accepted at once. Using one of the keep-alive
20854 modes may display larger idle times since "Ti" measures the time spent
Patrick Mezard105faca2010-06-12 17:02:46 +020020855 waiting for additional requests.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020856
20857 - If "Tc" is close to 3000, a packet has probably been lost between the
20858 server and the proxy during the server connection phase. This value should
20859 always be very low, such as 1 ms on local networks and less than a few tens
20860 of ms on remote networks.
20861
Willy Tarreau55165fe2009-05-10 12:02:55 +020020862 - If "Tr" is nearly always lower than 3000 except some rare values which seem
20863 to be the average majored by 3000, there are probably some packets lost
20864 between the proxy and the server.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020865
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020866 - If "Ta" is large even for small byte counts, it generally is because
20867 neither the client nor the server decides to close the connection while
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020868 HAProxy is running in tunnel mode and both have agreed on a keep-alive
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020869 connection mode. In order to solve this issue, it will be needed to specify
20870 one of the HTTP options to manipulate keep-alive or close options on either
20871 the frontend or the backend. Having the smallest possible 'Ta' or 'Tt' is
20872 important when connection regulation is used with the "maxconn" option on
20873 the servers, since no new connection will be sent to the server until
20874 another one is released.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020875
20876Other noticeable HTTP log cases ('xx' means any value to be ignored) :
20877
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020878 TR/Tw/Tc/Tr/+Ta The "option logasap" is present on the frontend and the log
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020879 was emitted before the data phase. All the timers are valid
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020880 except "Ta" which is shorter than reality.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020881
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020882 -1/xx/xx/xx/Ta The client was not able to send a complete request in time
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020883 or it aborted too early. Check the session termination flags
20884 then "timeout http-request" and "timeout client" settings.
20885
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020886 TR/-1/xx/xx/Ta It was not possible to process the request, maybe because
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020887 servers were out of order, because the request was invalid
20888 or forbidden by ACL rules. Check the session termination
20889 flags.
20890
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020891 TR/Tw/-1/xx/Ta The connection could not establish on the server. Either it
20892 actively refused it or it timed out after Ta-(TR+Tw) ms.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020893 Check the session termination flags, then check the
20894 "timeout connect" setting. Note that the tarpit action might
20895 return similar-looking patterns, with "Tw" equal to the time
20896 the client connection was maintained open.
20897
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020898 TR/Tw/Tc/-1/Ta The server has accepted the connection but did not return
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030020899 a complete response in time, or it closed its connection
Thierry FOURNIER / OZON.IO4cac3592016-07-28 17:19:45 +020020900 unexpectedly after Ta-(TR+Tw+Tc) ms. Check the session
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020901 termination flags, then check the "timeout server" setting.
20902
20903
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200209048.5. Session state at disconnection
20905-----------------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020906
20907TCP and HTTP logs provide a session termination indicator in the
20908"termination_state" field, just before the number of active connections. It is
209092-characters long in TCP mode, and is extended to 4 characters in HTTP mode,
20910each of which has a special meaning :
20911
20912 - On the first character, a code reporting the first event which caused the
20913 session to terminate :
20914
20915 C : the TCP session was unexpectedly aborted by the client.
20916
20917 S : the TCP session was unexpectedly aborted by the server, or the
20918 server explicitly refused it.
20919
20920 P : the session was prematurely aborted by the proxy, because of a
20921 connection limit enforcement, because a DENY filter was matched,
20922 because of a security check which detected and blocked a dangerous
20923 error in server response which might have caused information leak
Davor Ocelice9ed2812017-12-25 17:49:28 +010020924 (e.g. cacheable cookie).
Willy Tarreau570f2212013-06-10 16:42:09 +020020925
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020926 L : the session was locally processed by HAProxy and was not passed to
Willy Tarreau570f2212013-06-10 16:42:09 +020020927 a server. This is what happens for stats and redirects.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020928
20929 R : a resource on the proxy has been exhausted (memory, sockets, source
20930 ports, ...). Usually, this appears during the connection phase, and
20931 system logs should contain a copy of the precise error. If this
20932 happens, it must be considered as a very serious anomaly which
20933 should be fixed as soon as possible by any means.
20934
20935 I : an internal error was identified by the proxy during a self-check.
20936 This should NEVER happen, and you are encouraged to report any log
20937 containing this, because this would almost certainly be a bug. It
20938 would be wise to preventively restart the process after such an
20939 event too, in case it would be caused by memory corruption.
20940
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020941 D : the session was killed by HAProxy because the server was detected
Simon Horman752dc4a2011-06-21 14:34:59 +090020942 as down and was configured to kill all connections when going down.
20943
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020944 U : the session was killed by HAProxy on this backup server because an
Justin Karnegeseb2c24a2012-05-24 15:28:52 -070020945 active server was detected as up and was configured to kill all
20946 backup connections when going up.
20947
Daniel Corbett9f0843f2021-05-08 10:50:37 -040020948 K : the session was actively killed by an admin operating on HAProxy.
Willy Tarreaua2a64e92011-09-07 23:01:56 +020020949
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020950 c : the client-side timeout expired while waiting for the client to
20951 send or receive data.
20952
20953 s : the server-side timeout expired while waiting for the server to
20954 send or receive data.
20955
20956 - : normal session completion, both the client and the server closed
20957 with nothing left in the buffers.
20958
20959 - on the second character, the TCP or HTTP session state when it was closed :
20960
Willy Tarreauf7b30a92010-12-06 22:59:17 +010020961 R : the proxy was waiting for a complete, valid REQUEST from the client
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020962 (HTTP mode only). Nothing was sent to any server.
20963
20964 Q : the proxy was waiting in the QUEUE for a connection slot. This can
20965 only happen when servers have a 'maxconn' parameter set. It can
20966 also happen in the global queue after a redispatch consecutive to
20967 a failed attempt to connect to a dying server. If no redispatch is
20968 reported, then no connection attempt was made to any server.
20969
20970 C : the proxy was waiting for the CONNECTION to establish on the
20971 server. The server might at most have noticed a connection attempt.
20972
20973 H : the proxy was waiting for complete, valid response HEADERS from the
20974 server (HTTP only).
20975
20976 D : the session was in the DATA phase.
20977
20978 L : the proxy was still transmitting LAST data to the client while the
20979 server had already finished. This one is very rare as it can only
20980 happen when the client dies while receiving the last packets.
20981
20982 T : the request was tarpitted. It has been held open with the client
20983 during the whole "timeout tarpit" duration or until the client
20984 closed, both of which will be reported in the "Tw" timer.
20985
20986 - : normal session completion after end of data transfer.
20987
20988 - the third character tells whether the persistence cookie was provided by
20989 the client (only in HTTP mode) :
20990
20991 N : the client provided NO cookie. This is usually the case for new
20992 visitors, so counting the number of occurrences of this flag in the
20993 logs generally indicate a valid trend for the site frequentation.
20994
20995 I : the client provided an INVALID cookie matching no known server.
20996 This might be caused by a recent configuration change, mixed
Cyril Bontéa8e7bbc2010-04-25 22:29:29 +020020997 cookies between HTTP/HTTPS sites, persistence conditionally
20998 ignored, or an attack.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010020999
21000 D : the client provided a cookie designating a server which was DOWN,
21001 so either "option persist" was used and the client was sent to
21002 this server, or it was not set and the client was redispatched to
21003 another server.
21004
Willy Tarreau996a92c2010-10-13 19:30:47 +020021005 V : the client provided a VALID cookie, and was sent to the associated
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021006 server.
21007
Willy Tarreau996a92c2010-10-13 19:30:47 +020021008 E : the client provided a valid cookie, but with a last date which was
21009 older than what is allowed by the "maxidle" cookie parameter, so
21010 the cookie is consider EXPIRED and is ignored. The request will be
21011 redispatched just as if there was no cookie.
21012
21013 O : the client provided a valid cookie, but with a first date which was
21014 older than what is allowed by the "maxlife" cookie parameter, so
21015 the cookie is consider too OLD and is ignored. The request will be
21016 redispatched just as if there was no cookie.
21017
Willy Tarreauc89ccb62012-04-05 21:18:22 +020021018 U : a cookie was present but was not used to select the server because
21019 some other server selection mechanism was used instead (typically a
21020 "use-server" rule).
21021
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021022 - : does not apply (no cookie set in configuration).
21023
21024 - the last character reports what operations were performed on the persistence
21025 cookie returned by the server (only in HTTP mode) :
21026
21027 N : NO cookie was provided by the server, and none was inserted either.
21028
21029 I : no cookie was provided by the server, and the proxy INSERTED one.
21030 Note that in "cookie insert" mode, if the server provides a cookie,
21031 it will still be overwritten and reported as "I" here.
21032
Willy Tarreau996a92c2010-10-13 19:30:47 +020021033 U : the proxy UPDATED the last date in the cookie that was presented by
21034 the client. This can only happen in insert mode with "maxidle". It
Jarno Huuskonen0e82b922014-04-12 18:22:19 +030021035 happens every time there is activity at a different date than the
Willy Tarreau996a92c2010-10-13 19:30:47 +020021036 date indicated in the cookie. If any other change happens, such as
21037 a redispatch, then the cookie will be marked as inserted instead.
21038
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021039 P : a cookie was PROVIDED by the server and transmitted as-is.
21040
21041 R : the cookie provided by the server was REWRITTEN by the proxy, which
21042 happens in "cookie rewrite" or "cookie prefix" modes.
21043
21044 D : the cookie provided by the server was DELETED by the proxy.
21045
21046 - : does not apply (no cookie set in configuration).
21047
Willy Tarreau996a92c2010-10-13 19:30:47 +020021048The combination of the two first flags gives a lot of information about what
21049was happening when the session terminated, and why it did terminate. It can be
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021050helpful to detect server saturation, network troubles, local system resource
21051starvation, attacks, etc...
21052
21053The most common termination flags combinations are indicated below. They are
21054alphabetically sorted, with the lowercase set just after the upper case for
21055easier finding and understanding.
21056
21057 Flags Reason
21058
21059 -- Normal termination.
21060
21061 CC The client aborted before the connection could be established to the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021062 server. This can happen when HAProxy tries to connect to a recently
21063 dead (or unchecked) server, and the client aborts while HAProxy is
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021064 waiting for the server to respond or for "timeout connect" to expire.
21065
21066 CD The client unexpectedly aborted during data transfer. This can be
21067 caused by a browser crash, by an intermediate equipment between the
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021068 client and HAProxy which decided to actively break the connection,
21069 by network routing issues between the client and HAProxy, or by a
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021070 keep-alive session between the server and the client terminated first
21071 by the client.
Willy Tarreaud72758d2010-01-12 10:42:19 +010021072
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021073 cD The client did not send nor acknowledge any data for as long as the
21074 "timeout client" delay. This is often caused by network failures on
Cyril Bontédc4d9032012-04-08 21:57:39 +020021075 the client side, or the client simply leaving the net uncleanly.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021076
21077 CH The client aborted while waiting for the server to start responding.
21078 It might be the server taking too long to respond or the client
21079 clicking the 'Stop' button too fast.
21080
21081 cH The "timeout client" stroke while waiting for client data during a
21082 POST request. This is sometimes caused by too large TCP MSS values
21083 for PPPoE networks which cannot transport full-sized packets. It can
21084 also happen when client timeout is smaller than server timeout and
21085 the server takes too long to respond.
21086
21087 CQ The client aborted while its session was queued, waiting for a server
21088 with enough empty slots to accept it. It might be that either all the
21089 servers were saturated or that the assigned server was taking too
21090 long a time to respond.
21091
21092 CR The client aborted before sending a full HTTP request. Most likely
21093 the request was typed by hand using a telnet client, and aborted
21094 too early. The HTTP status code is likely a 400 here. Sometimes this
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021095 might also be caused by an IDS killing the connection between HAProxy
Willy Tarreau0f228a02015-05-01 15:37:53 +020021096 and the client. "option http-ignore-probes" can be used to ignore
21097 connections without any data transfer.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021098
21099 cR The "timeout http-request" stroke before the client sent a full HTTP
21100 request. This is sometimes caused by too large TCP MSS values on the
21101 client side for PPPoE networks which cannot transport full-sized
21102 packets, or by clients sending requests by hand and not typing fast
21103 enough, or forgetting to enter the empty line at the end of the
Willy Tarreau2705a612014-05-23 17:38:34 +020021104 request. The HTTP status code is likely a 408 here. Note: recently,
Willy Tarreau0f228a02015-05-01 15:37:53 +020021105 some browsers started to implement a "pre-connect" feature consisting
21106 in speculatively connecting to some recently visited web sites just
21107 in case the user would like to visit them. This results in many
21108 connections being established to web sites, which end up in 408
21109 Request Timeout if the timeout strikes first, or 400 Bad Request when
21110 the browser decides to close them first. These ones pollute the log
21111 and feed the error counters. Some versions of some browsers have even
21112 been reported to display the error code. It is possible to work
Davor Ocelice9ed2812017-12-25 17:49:28 +010021113 around the undesirable effects of this behavior by adding "option
Willy Tarreau0f228a02015-05-01 15:37:53 +020021114 http-ignore-probes" in the frontend, resulting in connections with
21115 zero data transfer to be totally ignored. This will definitely hide
21116 the errors of people experiencing connectivity issues though.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021117
21118 CT The client aborted while its session was tarpitted. It is important to
21119 check if this happens on valid requests, in order to be sure that no
Willy Tarreau55165fe2009-05-10 12:02:55 +020021120 wrong tarpit rules have been written. If a lot of them happen, it
21121 might make sense to lower the "timeout tarpit" value to something
21122 closer to the average reported "Tw" timer, in order not to consume
21123 resources for just a few attackers.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021124
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021125 LR The request was intercepted and locally handled by HAProxy. Generally
Willy Tarreau570f2212013-06-10 16:42:09 +020021126 it means that this was a redirect or a stats request.
21127
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021128 SC The server or an equipment between it and HAProxy explicitly refused
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021129 the TCP connection (the proxy received a TCP RST or an ICMP message
21130 in return). Under some circumstances, it can also be the network
Davor Ocelice9ed2812017-12-25 17:49:28 +010021131 stack telling the proxy that the server is unreachable (e.g. no route,
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021132 or no ARP response on local network). When this happens in HTTP mode,
21133 the status code is likely a 502 or 503 here.
21134
21135 sC The "timeout connect" stroke before a connection to the server could
21136 complete. When this happens in HTTP mode, the status code is likely a
21137 503 or 504 here.
21138
21139 SD The connection to the server died with an error during the data
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021140 transfer. This usually means that HAProxy has received an RST from
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021141 the server or an ICMP message from an intermediate equipment while
21142 exchanging data with the server. This can be caused by a server crash
21143 or by a network issue on an intermediate equipment.
21144
21145 sD The server did not send nor acknowledge any data for as long as the
21146 "timeout server" setting during the data phase. This is often caused
Davor Ocelice9ed2812017-12-25 17:49:28 +010021147 by too short timeouts on L4 equipment before the server (firewalls,
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021148 load-balancers, ...), as well as keep-alive sessions maintained
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021149 between the client and the server expiring first on HAProxy.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021150
21151 SH The server aborted before sending its full HTTP response headers, or
21152 it crashed while processing the request. Since a server aborting at
21153 this moment is very rare, it would be wise to inspect its logs to
21154 control whether it crashed and why. The logged request may indicate a
21155 small set of faulty requests, demonstrating bugs in the application.
21156 Sometimes this might also be caused by an IDS killing the connection
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021157 between HAProxy and the server.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021158
21159 sH The "timeout server" stroke before the server could return its
21160 response headers. This is the most common anomaly, indicating too
21161 long transactions, probably caused by server or database saturation.
21162 The immediate workaround consists in increasing the "timeout server"
21163 setting, but it is important to keep in mind that the user experience
21164 will suffer from these long response times. The only long term
21165 solution is to fix the application.
21166
21167 sQ The session spent too much time in queue and has been expired. See
21168 the "timeout queue" and "timeout connect" settings to find out how to
21169 fix this if it happens too often. If it often happens massively in
21170 short periods, it may indicate general problems on the affected
21171 servers due to I/O or database congestion, or saturation caused by
21172 external attacks.
21173
21174 PC The proxy refused to establish a connection to the server because the
Thayne McCombscdbcca92021-01-07 21:24:41 -070021175 process's socket limit has been reached while attempting to connect.
Cyril Bontédc4d9032012-04-08 21:57:39 +020021176 The global "maxconn" parameter may be increased in the configuration
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021177 so that it does not happen anymore. This status is very rare and
21178 might happen when the global "ulimit-n" parameter is forced by hand.
21179
Willy Tarreaued2fd2d2010-12-29 11:23:27 +010021180 PD The proxy blocked an incorrectly formatted chunked encoded message in
21181 a request or a response, after the server has emitted its headers. In
21182 most cases, this will indicate an invalid message from the server to
Davor Ocelice9ed2812017-12-25 17:49:28 +010021183 the client. HAProxy supports chunk sizes of up to 2GB - 1 (2147483647
Willy Tarreauf3a3e132013-08-31 08:16:26 +020021184 bytes). Any larger size will be considered as an error.
Willy Tarreaued2fd2d2010-12-29 11:23:27 +010021185
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021186 PH The proxy blocked the server's response, because it was invalid,
21187 incomplete, dangerous (cache control), or matched a security filter.
21188 In any case, an HTTP 502 error is sent to the client. One possible
21189 cause for this error is an invalid syntax in an HTTP header name
Willy Tarreaued2fd2d2010-12-29 11:23:27 +010021190 containing unauthorized characters. It is also possible but quite
21191 rare, that the proxy blocked a chunked-encoding request from the
21192 client due to an invalid syntax, before the server responded. In this
21193 case, an HTTP 400 error is sent to the client and reported in the
21194 logs.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021195
21196 PR The proxy blocked the client's HTTP request, either because of an
21197 invalid HTTP syntax, in which case it returned an HTTP 400 error to
21198 the client, or because a deny filter matched, in which case it
21199 returned an HTTP 403 error.
21200
21201 PT The proxy blocked the client's request and has tarpitted its
21202 connection before returning it a 500 server error. Nothing was sent
21203 to the server. The connection was maintained open for as long as
21204 reported by the "Tw" timer field.
21205
21206 RC A local resource has been exhausted (memory, sockets, source ports)
21207 preventing the connection to the server from establishing. The error
21208 logs will tell precisely what was missing. This is very rare and can
21209 only be solved by proper system tuning.
21210
Willy Tarreau996a92c2010-10-13 19:30:47 +020021211The combination of the two last flags gives a lot of information about how
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021212persistence was handled by the client, the server and by HAProxy. This is very
Willy Tarreau996a92c2010-10-13 19:30:47 +020021213important to troubleshoot disconnections, when users complain they have to
21214re-authenticate. The commonly encountered flags are :
21215
21216 -- Persistence cookie is not enabled.
21217
21218 NN No cookie was provided by the client, none was inserted in the
21219 response. For instance, this can be in insert mode with "postonly"
21220 set on a GET request.
21221
21222 II A cookie designating an invalid server was provided by the client,
21223 a valid one was inserted in the response. This typically happens when
Jamie Gloudonaaa21002012-08-25 00:18:33 -040021224 a "server" entry is removed from the configuration, since its cookie
Willy Tarreau996a92c2010-10-13 19:30:47 +020021225 value can be presented by a client when no other server knows it.
21226
21227 NI No cookie was provided by the client, one was inserted in the
21228 response. This typically happens for first requests from every user
21229 in "insert" mode, which makes it an easy way to count real users.
21230
21231 VN A cookie was provided by the client, none was inserted in the
21232 response. This happens for most responses for which the client has
21233 already got a cookie.
21234
21235 VU A cookie was provided by the client, with a last visit date which is
21236 not completely up-to-date, so an updated cookie was provided in
21237 response. This can also happen if there was no date at all, or if
21238 there was a date but the "maxidle" parameter was not set, so that the
21239 cookie can be switched to unlimited time.
21240
21241 EI A cookie was provided by the client, with a last visit date which is
21242 too old for the "maxidle" parameter, so the cookie was ignored and a
21243 new cookie was inserted in the response.
21244
21245 OI A cookie was provided by the client, with a first visit date which is
21246 too old for the "maxlife" parameter, so the cookie was ignored and a
21247 new cookie was inserted in the response.
21248
21249 DI The server designated by the cookie was down, a new server was
21250 selected and a new cookie was emitted in the response.
21251
21252 VI The server designated by the cookie was not marked dead but could not
21253 be reached. A redispatch happened and selected another one, which was
21254 then advertised in the response.
21255
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021256
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200212578.6. Non-printable characters
21258-----------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021259
21260In order not to cause trouble to log analysis tools or terminals during log
21261consulting, non-printable characters are not sent as-is into log files, but are
21262converted to the two-digits hexadecimal representation of their ASCII code,
21263prefixed by the character '#'. The only characters that can be logged without
21264being escaped are comprised between 32 and 126 (inclusive). Obviously, the
21265escape character '#' itself is also encoded to avoid any ambiguity ("#23"). It
21266is the same for the character '"' which becomes "#22", as well as '{', '|' and
21267'}' when logging headers.
21268
21269Note that the space character (' ') is not encoded in headers, which can cause
21270issues for tools relying on space count to locate fields. A typical header
21271containing spaces is "User-Agent".
21272
21273Last, it has been observed that some syslog daemons such as syslog-ng escape
21274the quote ('"') with a backslash ('\'). The reverse operation can safely be
21275performed since no quote may appear anywhere else in the logs.
21276
21277
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200212788.7. Capturing HTTP cookies
21279---------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021280
21281Cookie capture simplifies the tracking a complete user session. This can be
21282achieved using the "capture cookie" statement in the frontend. Please refer to
Willy Tarreauc57f0e22009-05-10 13:12:33 +020021283section 4.2 for more details. Only one cookie can be captured, and the same
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021284cookie will simultaneously be checked in the request ("Cookie:" header) and in
21285the response ("Set-Cookie:" header). The respective values will be reported in
21286the HTTP logs at the "captured_request_cookie" and "captured_response_cookie"
Willy Tarreauc57f0e22009-05-10 13:12:33 +020021287locations (see section 8.2.3 about HTTP log format). When either cookie is
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021288not seen, a dash ('-') replaces the value. This way, it's easy to detect when a
21289user switches to a new session for example, because the server will reassign it
21290a new cookie. It is also possible to detect if a server unexpectedly sets a
21291wrong cookie to a client, leading to session crossing.
21292
21293 Examples :
21294 # capture the first cookie whose name starts with "ASPSESSION"
21295 capture cookie ASPSESSION len 32
21296
21297 # capture the first cookie whose name is exactly "vgnvisitor"
21298 capture cookie vgnvisitor= len 32
21299
21300
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200213018.8. Capturing HTTP headers
21302---------------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021303
21304Header captures are useful to track unique request identifiers set by an upper
21305proxy, virtual host names, user-agents, POST content-length, referrers, etc. In
21306the response, one can search for information about the response length, how the
21307server asked the cache to behave, or an object location during a redirection.
21308
21309Header captures are performed using the "capture request header" and "capture
21310response header" statements in the frontend. Please consult their definition in
Willy Tarreauc57f0e22009-05-10 13:12:33 +020021311section 4.2 for more details.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021312
21313It is possible to include both request headers and response headers at the same
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010021314time. Non-existent headers are logged as empty strings, and if one header
21315appears more than once, only its last occurrence will be logged. Request headers
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021316are grouped within braces '{' and '}' in the same order as they were declared,
21317and delimited with a vertical bar '|' without any space. Response headers
21318follow the same representation, but are displayed after a space following the
21319request headers block. These blocks are displayed just before the HTTP request
21320in the logs.
21321
Willy Tarreaud9ed3d22014-06-13 12:23:06 +020021322As a special case, it is possible to specify an HTTP header capture in a TCP
21323frontend. The purpose is to enable logging of headers which will be parsed in
21324an HTTP backend if the request is then switched to this HTTP backend.
21325
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021326 Example :
21327 # This instance chains to the outgoing proxy
21328 listen proxy-out
21329 mode http
21330 option httplog
21331 option logasap
21332 log global
21333 server cache1 192.168.1.1:3128
21334
21335 # log the name of the virtual server
21336 capture request header Host len 20
21337
21338 # log the amount of data uploaded during a POST
21339 capture request header Content-Length len 10
21340
21341 # log the beginning of the referrer
21342 capture request header Referer len 20
21343
21344 # server name (useful for outgoing proxies only)
21345 capture response header Server len 20
21346
21347 # logging the content-length is useful with "option logasap"
21348 capture response header Content-Length len 10
21349
Davor Ocelice9ed2812017-12-25 17:49:28 +010021350 # log the expected cache behavior on the response
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021351 capture response header Cache-Control len 8
21352
21353 # the Via header will report the next proxy's name
21354 capture response header Via len 20
21355
21356 # log the URL location during a redirection
21357 capture response header Location len 20
21358
21359 >>> Aug 9 20:26:09 localhost \
21360 haproxy[2022]: 127.0.0.1:34014 [09/Aug/2004:20:26:09] proxy-out \
21361 proxy-out/cache1 0/0/0/162/+162 200 +350 - - ---- 0/0/0/0/0 0/0 \
21362 {fr.adserver.yahoo.co||http://fr.f416.mail.} {|864|private||} \
21363 "GET http://fr.adserver.yahoo.com/"
21364
21365 >>> Aug 9 20:30:46 localhost \
21366 haproxy[2022]: 127.0.0.1:34020 [09/Aug/2004:20:30:46] proxy-out \
21367 proxy-out/cache1 0/0/0/182/+182 200 +279 - - ---- 0/0/0/0/0 0/0 \
21368 {w.ods.org||} {Formilux/0.1.8|3495|||} \
Willy Tarreaud72758d2010-01-12 10:42:19 +010021369 "GET http://trafic.1wt.eu/ HTTP/1.1"
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021370
21371 >>> Aug 9 20:30:46 localhost \
21372 haproxy[2022]: 127.0.0.1:34028 [09/Aug/2004:20:30:46] proxy-out \
21373 proxy-out/cache1 0/0/2/126/+128 301 +223 - - ---- 0/0/0/0/0 0/0 \
21374 {www.sytadin.equipement.gouv.fr||http://trafic.1wt.eu/} \
21375 {Apache|230|||http://www.sytadin.} \
Willy Tarreaud72758d2010-01-12 10:42:19 +010021376 "GET http://www.sytadin.equipement.gouv.fr/ HTTP/1.1"
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021377
21378
Willy Tarreauc57f0e22009-05-10 13:12:33 +0200213798.9. Examples of logs
21380---------------------
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021381
21382These are real-world examples of logs accompanied with an explanation. Some of
21383them have been made up by hand. The syslog part has been removed for better
21384reading. Their sole purpose is to explain how to decipher them.
21385
21386 >>> haproxy[674]: 127.0.0.1:33318 [15/Oct/2003:08:31:57.130] px-http \
21387 px-http/srv1 6559/0/7/147/6723 200 243 - - ---- 5/3/3/1/0 0/0 \
21388 "HEAD / HTTP/1.0"
21389
21390 => long request (6.5s) entered by hand through 'telnet'. The server replied
21391 in 147 ms, and the session ended normally ('----')
21392
21393 >>> haproxy[674]: 127.0.0.1:33319 [15/Oct/2003:08:31:57.149] px-http \
21394 px-http/srv1 6559/1230/7/147/6870 200 243 - - ---- 324/239/239/99/0 \
21395 0/9 "HEAD / HTTP/1.0"
21396
21397 => Idem, but the request was queued in the global queue behind 9 other
21398 requests, and waited there for 1230 ms.
21399
21400 >>> haproxy[674]: 127.0.0.1:33320 [15/Oct/2003:08:32:17.654] px-http \
21401 px-http/srv1 9/0/7/14/+30 200 +243 - - ---- 3/3/3/1/0 0/0 \
21402 "GET /image.iso HTTP/1.0"
21403
21404 => request for a long data transfer. The "logasap" option was specified, so
Krzysztof Piotr Oledzkif8645332009-12-13 21:55:50 +010021405 the log was produced just before transferring data. The server replied in
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021406 14 ms, 243 bytes of headers were sent to the client, and total time from
21407 accept to first data byte is 30 ms.
21408
21409 >>> haproxy[674]: 127.0.0.1:33320 [15/Oct/2003:08:32:17.925] px-http \
21410 px-http/srv1 9/0/7/14/30 502 243 - - PH-- 3/2/2/0/0 0/0 \
21411 "GET /cgi-bin/bug.cgi? HTTP/1.0"
21412
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020021413 => the proxy blocked a server response either because of an "http-response
21414 deny" rule, or because the response was improperly formatted and not
21415 HTTP-compliant, or because it blocked sensitive information which risked
21416 being cached. In this case, the response is replaced with a "502 bad
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021417 gateway". The flags ("PH--") tell us that it was HAProxy who decided to
Christopher Faulet87f1f3d2019-07-18 14:51:20 +020021418 return the 502 and not the server.
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021419
21420 >>> haproxy[18113]: 127.0.0.1:34548 [15/Oct/2003:15:18:55.798] px-http \
Willy Tarreaud72758d2010-01-12 10:42:19 +010021421 px-http/<NOSRV> -1/-1/-1/-1/8490 -1 0 - - CR-- 2/2/2/0/0 0/0 ""
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021422
21423 => the client never completed its request and aborted itself ("C---") after
21424 8.5s, while the proxy was waiting for the request headers ("-R--").
21425 Nothing was sent to any server.
21426
21427 >>> haproxy[18113]: 127.0.0.1:34549 [15/Oct/2003:15:19:06.103] px-http \
21428 px-http/<NOSRV> -1/-1/-1/-1/50001 408 0 - - cR-- 2/2/2/0/0 0/0 ""
21429
21430 => The client never completed its request, which was aborted by the
21431 time-out ("c---") after 50s, while the proxy was waiting for the request
Davor Ocelice9ed2812017-12-25 17:49:28 +010021432 headers ("-R--"). Nothing was sent to any server, but the proxy could
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021433 send a 408 return code to the client.
21434
21435 >>> haproxy[18989]: 127.0.0.1:34550 [15/Oct/2003:15:24:28.312] px-tcp \
21436 px-tcp/srv1 0/0/5007 0 cD 0/0/0/0/0 0/0
21437
21438 => This log was produced with "option tcplog". The client timed out after
21439 5 seconds ("c----").
21440
21441 >>> haproxy[18989]: 10.0.0.1:34552 [15/Oct/2003:15:26:31.462] px-http \
21442 px-http/srv1 3183/-1/-1/-1/11215 503 0 - - SC-- 205/202/202/115/3 \
Willy Tarreaud72758d2010-01-12 10:42:19 +010021443 0/0 "HEAD / HTTP/1.0"
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021444
21445 => The request took 3s to complete (probably a network problem), and the
Willy Tarreauc57f0e22009-05-10 13:12:33 +020021446 connection to the server failed ('SC--') after 4 attempts of 2 seconds
Willy Tarreaucc6c8912009-02-22 10:53:55 +010021447 (config says 'retries 3'), and no redispatch (otherwise we would have
21448 seen "/+3"). Status code 503 was returned to the client. There were 115
21449 connections on this server, 202 connections on this proxy, and 205 on
21450 the global process. It is possible that the server refused the
21451 connection because of too many already established.
Willy Tarreau844e3c52008-01-11 16:28:18 +010021452
Willy Tarreau52b2d222011-09-07 23:48:48 +020021453
Christopher Fauletc3fe5332016-04-07 15:30:10 +0200214549. Supported filters
21455--------------------
21456
21457Here are listed officially supported filters with the list of parameters they
21458accept. Depending on compile options, some of these filters might be
21459unavailable. The list of available filters is reported in haproxy -vv.
21460
21461See also : "filter"
21462
214639.1. Trace
21464----------
21465
Christopher Fauletc41d8bd2020-11-17 10:43:26 +010021466filter trace [name <name>] [random-forwarding] [hexdump]
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021467
21468 Arguments:
21469 <name> is an arbitrary name that will be reported in
21470 messages. If no name is provided, "TRACE" is used.
21471
Christopher Faulet96a577a2020-11-17 10:45:05 +010021472 <quiet> inhibits trace messages.
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021473
Davor Ocelice9ed2812017-12-25 17:49:28 +010021474 <random-forwarding> enables the random forwarding of parsed data. By
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021475 default, this filter forwards all previously parsed
21476 data. With this parameter, it only forwards a random
21477 amount of the parsed data.
21478
Davor Ocelice9ed2812017-12-25 17:49:28 +010021479 <hexdump> dumps all forwarded data to the server and the client.
Christopher Faulet31bfe1f2016-12-09 17:42:38 +010021480
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021481This filter can be used as a base to develop new filters. It defines all
21482callbacks and print a message on the standard error stream (stderr) with useful
21483information for all of them. It may be useful to debug the activity of other
21484filters or, quite simply, HAProxy's activity.
21485
21486Using <random-parsing> and/or <random-forwarding> parameters is a good way to
21487tests the behavior of a filter that parses data exchanged between a client and
21488a server by adding some latencies in the processing.
21489
21490
214919.2. HTTP compression
21492---------------------
21493
21494filter compression
21495
21496The HTTP compression has been moved in a filter in HAProxy 1.7. "compression"
21497keyword must still be used to enable and configure the HTTP compression. And
Christopher Fauletb30b3102019-09-12 23:03:09 +020021498when no other filter is used, it is enough. When used with the cache or the
21499fcgi-app enabled, it is also enough. In this case, the compression is always
21500done after the response is stored in the cache. But it is mandatory to
21501explicitly use a filter line to enable the HTTP compression when at least one
21502filter other than the cache or the fcgi-app is used for the same
21503listener/frontend/backend. This is important to know the filters evaluation
21504order.
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021505
Christopher Fauletb30b3102019-09-12 23:03:09 +020021506See also : "compression", section 9.4 about the cache filter and section 9.5
21507 about the fcgi-app filter.
Christopher Fauletc3fe5332016-04-07 15:30:10 +020021508
21509
Christopher Fauletf7e4e7e2016-10-27 22:29:49 +0200215109.3. Stream Processing Offload Engine (SPOE)
21511--------------------------------------------
21512
21513filter spoe [engine <name>] config <file>
21514
21515 Arguments :
21516
21517 <name> is the engine name that will be used to find the right scope in
21518 the configuration file. If not provided, all the file will be
21519 parsed.
21520
21521 <file> is the path of the engine configuration file. This file can
21522 contain configuration of several engines. In this case, each
21523 part must be placed in its own scope.
21524
21525The Stream Processing Offload Engine (SPOE) is a filter communicating with
21526external components. It allows the offload of some specifics processing on the
Davor Ocelice9ed2812017-12-25 17:49:28 +010021527streams in tiered applications. These external components and information
Christopher Fauletf7e4e7e2016-10-27 22:29:49 +020021528exchanged with them are configured in dedicated files, for the main part. It
21529also requires dedicated backends, defined in HAProxy configuration.
21530
21531SPOE communicates with external components using an in-house binary protocol,
21532the Stream Processing Offload Protocol (SPOP).
21533
Tim Düsterhus4896c442016-11-29 02:15:19 +010021534For all information about the SPOE configuration and the SPOP specification, see
Christopher Fauletf7e4e7e2016-10-27 22:29:49 +020021535"doc/SPOE.txt".
21536
Christopher Faulet99a17a22018-12-11 09:18:27 +0100215379.4. Cache
21538----------
21539
21540filter cache <name>
21541
21542 Arguments :
21543
21544 <name> is name of the cache section this filter will use.
21545
21546The cache uses a filter to store cacheable responses. The HTTP rules
21547"cache-store" and "cache-use" must be used to define how and when to use a
John Roeslerfb2fce12019-07-10 15:45:51 -050021548cache. By default the corresponding filter is implicitly defined. And when no
Christopher Fauletb30b3102019-09-12 23:03:09 +020021549other filters than fcgi-app or compression are used, it is enough. In such
21550case, the compression filter is always evaluated after the cache filter. But it
21551is mandatory to explicitly use a filter line to use a cache when at least one
21552filter other than the compression or the fcgi-app is used for the same
Christopher Faulet27d93c32018-12-15 22:32:02 +010021553listener/frontend/backend. This is important to know the filters evaluation
21554order.
Christopher Faulet99a17a22018-12-11 09:18:27 +010021555
Christopher Fauletb30b3102019-09-12 23:03:09 +020021556See also : section 9.2 about the compression filter, section 9.5 about the
21557 fcgi-app filter and section 6 about cache.
21558
21559
215609.5. Fcgi-app
21561-------------
21562
Daniel Corbett67a82712020-07-06 23:01:19 -040021563filter fcgi-app <name>
Christopher Fauletb30b3102019-09-12 23:03:09 +020021564
21565 Arguments :
21566
21567 <name> is name of the fcgi-app section this filter will use.
21568
21569The FastCGI application uses a filter to evaluate all custom parameters on the
21570request path, and to process the headers on the response path. the <name> must
21571reference an existing fcgi-app section. The directive "use-fcgi-app" should be
21572used to define the application to use. By default the corresponding filter is
21573implicitly defined. And when no other filters than cache or compression are
21574used, it is enough. But it is mandatory to explicitly use a filter line to a
21575fcgi-app when at least one filter other than the compression or the cache is
21576used for the same backend. This is important to know the filters evaluation
21577order.
21578
21579See also: "use-fcgi-app", section 9.2 about the compression filter, section 9.4
21580 about the cache filter and section 10 about FastCGI application.
21581
21582
Miroslav Zagoracdc32cd92020-12-13 18:32:57 +0100215839.6. OpenTracing
21584----------------
21585
21586The OpenTracing filter adds native support for using distributed tracing in
21587HAProxy. This is enabled by sending an OpenTracing compliant request to one
21588of the supported tracers such as Datadog, Jaeger, Lightstep and Zipkin tracers.
21589Please note: tracers are not listed by any preference, but alphabetically.
21590
Daniel Corbett9f0843f2021-05-08 10:50:37 -040021591This feature is only enabled when HAProxy was built with USE_OT=1.
Miroslav Zagoracdc32cd92020-12-13 18:32:57 +010021592
21593The OpenTracing filter activation is done explicitly by specifying it in the
21594HAProxy configuration. If this is not done, the OpenTracing filter in no way
21595participates in the work of HAProxy.
21596
21597filter opentracing [id <id>] config <file>
21598
21599 Arguments :
21600
21601 <id> is the OpenTracing filter id that will be used to find the
21602 right scope in the configuration file. If no filter id is
21603 specified, 'ot-filter' is used as default. If scope is not
21604 specified in the configuration file, it applies to all defined
21605 OpenTracing filters.
21606
21607 <file> is the path of the OpenTracing configuration file. The same
21608 file can contain configurations for multiple OpenTracing
21609 filters simultaneously. In that case we do not need to define
21610 scope so the same configuration applies to all filters or each
21611 filter must have its own scope defined.
21612
21613More detailed documentation related to the operation, configuration and use
Willy Tarreaua63d1a02021-04-02 17:16:46 +020021614of the filter can be found in the addons/ot directory.
Miroslav Zagoracdc32cd92020-12-13 18:32:57 +010021615
21616
Christopher Fauletb30b3102019-09-12 23:03:09 +02002161710. FastCGI applications
21618-------------------------
21619
21620HAProxy is able to send HTTP requests to Responder FastCGI applications. This
21621feature was added in HAProxy 2.1. To do so, servers must be configured to use
21622the FastCGI protocol (using the keyword "proto fcgi" on the server line) and a
21623FastCGI application must be configured and used by the backend managing these
21624servers (using the keyword "use-fcgi-app" into the proxy section). Several
21625FastCGI applications may be defined, but only one can be used at a time by a
21626backend.
21627
21628HAProxy implements all features of the FastCGI specification for Responder
21629application. Especially it is able to multiplex several requests on a simple
21630connection.
21631
2163210.1. Setup
21633-----------
21634
2163510.1.1. Fcgi-app section
21636--------------------------
21637
21638fcgi-app <name>
21639 Declare a FastCGI application named <name>. To be valid, at least the
21640 document root must be defined.
21641
21642acl <aclname> <criterion> [flags] [operator] <value> ...
21643 Declare or complete an access list.
21644
21645 See "acl" keyword in section 4.2 and section 7 about ACL usage for
21646 details. ACLs defined for a FastCGI application are private. They cannot be
21647 used by any other application or by any proxy. In the same way, ACLs defined
21648 in any other section are not usable by a FastCGI application. However,
21649 Pre-defined ACLs are available.
21650
21651docroot <path>
21652 Define the document root on the remote host. <path> will be used to build
21653 the default value of FastCGI parameters SCRIPT_FILENAME and
21654 PATH_TRANSLATED. It is a mandatory setting.
21655
21656index <script-name>
21657 Define the script name that will be appended after an URI that ends with a
21658 slash ("/") to set the default value of the FastCGI parameter SCRIPT_NAME. It
21659 is an optional setting.
21660
21661 Example :
21662 index index.php
21663
21664log-stderr global
21665log-stderr <address> [len <length>] [format <format>]
Jan Wagner3e678602020-12-17 22:22:32 +010021666 [sample <ranges>:<sample_size>] <facility> [<level> [<minlevel>]]
Christopher Fauletb30b3102019-09-12 23:03:09 +020021667 Enable logging of STDERR messages reported by the FastCGI application.
21668
21669 See "log" keyword in section 4.2 for details. It is an optional setting. By
21670 default STDERR messages are ignored.
21671
21672pass-header <name> [ { if | unless } <condition> ]
21673 Specify the name of a request header which will be passed to the FastCGI
21674 application. It may optionally be followed by an ACL-based condition, in
21675 which case it will only be evaluated if the condition is true.
21676
21677 Most request headers are already available to the FastCGI application,
21678 prefixed with "HTTP_". Thus, this directive is only required to pass headers
21679 that are purposefully omitted. Currently, the headers "Authorization",
21680 "Proxy-Authorization" and hop-by-hop headers are omitted.
21681
21682 Note that the headers "Content-type" and "Content-length" are never passed to
21683 the FastCGI application because they are already converted into parameters.
21684
21685path-info <regex>
Christopher Faulet28cb3662020-02-14 14:47:37 +010021686 Define a regular expression to extract the script-name and the path-info from
Christopher Faulet6c57f2d2020-02-14 16:55:52 +010021687 the URL-decoded path. Thus, <regex> may have two captures: the first one to
21688 capture the script name and the second one to capture the path-info. The
21689 first one is mandatory, the second one is optional. This way, it is possible
21690 to extract the script-name from the path ignoring the path-info. It is an
21691 optional setting. If it is not defined, no matching is performed on the
21692 path. and the FastCGI parameters PATH_INFO and PATH_TRANSLATED are not
21693 filled.
Christopher Faulet28cb3662020-02-14 14:47:37 +010021694
21695 For security reason, when this regular expression is defined, the newline and
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050021696 the null characters are forbidden from the path, once URL-decoded. The reason
Christopher Faulet28cb3662020-02-14 14:47:37 +010021697 to such limitation is because otherwise the matching always fails (due to a
21698 limitation one the way regular expression are executed in HAProxy). So if one
21699 of these two characters is found in the URL-decoded path, an error is
21700 returned to the client. The principle of least astonishment is applied here.
Christopher Fauletb30b3102019-09-12 23:03:09 +020021701
21702 Example :
Christopher Faulet6c57f2d2020-02-14 16:55:52 +010021703 path-info ^(/.+\.php)(/.*)?$ # both script-name and path-info may be set
21704 path-info ^(/.+\.php) # the path-info is ignored
Christopher Fauletb30b3102019-09-12 23:03:09 +020021705
21706option get-values
21707no option get-values
21708 Enable or disable the retrieve of variables about connection management.
21709
Daniel Corbett67a82712020-07-06 23:01:19 -040021710 HAProxy is able to send the record FCGI_GET_VALUES on connection
Christopher Fauletb30b3102019-09-12 23:03:09 +020021711 establishment to retrieve the value for following variables:
21712
21713 * FCGI_MAX_REQS The maximum number of concurrent requests this
21714 application will accept.
21715
William Lallemand93e548e2019-09-30 13:54:02 +020021716 * FCGI_MPXS_CONNS "0" if this application does not multiplex connections,
21717 "1" otherwise.
Christopher Fauletb30b3102019-09-12 23:03:09 +020021718
21719 Some FastCGI applications does not support this feature. Some others close
Ilya Shipitsin11057a32020-06-21 21:18:27 +050021720 the connection immediately after sending their response. So, by default, this
Christopher Fauletb30b3102019-09-12 23:03:09 +020021721 option is disabled.
21722
21723 Note that the maximum number of concurrent requests accepted by a FastCGI
21724 application is a connection variable. It only limits the number of streams
21725 per connection. If the global load must be limited on the application, the
21726 server parameters "maxconn" and "pool-max-conn" must be set. In addition, if
21727 an application does not support connection multiplexing, the maximum number
21728 of concurrent requests is automatically set to 1.
21729
21730option keep-conn
21731no option keep-conn
21732 Instruct the FastCGI application to keep the connection open or not after
21733 sending a response.
21734
21735 If disabled, the FastCGI application closes the connection after responding
21736 to this request. By default, this option is enabled.
21737
21738option max-reqs <reqs>
21739 Define the maximum number of concurrent requests this application will
21740 accept.
21741
21742 This option may be overwritten if the variable FCGI_MAX_REQS is retrieved
21743 during connection establishment. Furthermore, if the application does not
21744 support connection multiplexing, this option will be ignored. By default set
21745 to 1.
21746
21747option mpxs-conns
21748no option mpxs-conns
21749 Enable or disable the support of connection multiplexing.
21750
21751 This option may be overwritten if the variable FCGI_MPXS_CONNS is retrieved
21752 during connection establishment. It is disabled by default.
21753
21754set-param <name> <fmt> [ { if | unless } <condition> ]
21755 Set a FastCGI parameter that should be passed to this application. Its
21756 value, defined by <fmt> must follows the log-format rules (see section 8.2.4
21757 "Custom Log format"). It may optionally be followed by an ACL-based
21758 condition, in which case it will only be evaluated if the condition is true.
21759
21760 With this directive, it is possible to overwrite the value of default FastCGI
21761 parameters. If the value is evaluated to an empty string, the rule is
21762 ignored. These directives are evaluated in their declaration order.
21763
21764 Example :
21765 # PHP only, required if PHP was built with --enable-force-cgi-redirect
21766 set-param REDIRECT_STATUS 200
21767
21768 set-param PHP_AUTH_DIGEST %[req.hdr(Authorization)]
21769
21770
2177110.1.2. Proxy section
21772---------------------
21773
21774use-fcgi-app <name>
21775 Define the FastCGI application to use for the backend.
21776
21777 Arguments :
21778 <name> is the name of the FastCGI application to use.
21779
21780 This keyword is only available for HTTP proxies with the backend capability
21781 and with at least one FastCGI server. However, FastCGI servers can be mixed
21782 with HTTP servers. But except there is a good reason to do so, it is not
21783 recommended (see section 10.3 about the limitations for details). Only one
21784 application may be defined at a time per backend.
21785
21786 Note that, once a FastCGI application is referenced for a backend, depending
21787 on the configuration some processing may be done even if the request is not
21788 sent to a FastCGI server. Rules to set parameters or pass headers to an
21789 application are evaluated.
21790
21791
2179210.1.3. Example
21793---------------
21794
21795 frontend front-http
21796 mode http
21797 bind *:80
21798 bind *:
21799
21800 use_backend back-dynamic if { path_reg ^/.+\.php(/.*)?$ }
21801 default_backend back-static
21802
21803 backend back-static
21804 mode http
21805 server www A.B.C.D:80
21806
21807 backend back-dynamic
21808 mode http
21809 use-fcgi-app php-fpm
21810 server php-fpm A.B.C.D:9000 proto fcgi
21811
21812 fcgi-app php-fpm
21813 log-stderr global
21814 option keep-conn
21815
21816 docroot /var/www/my-app
21817 index index.php
21818 path-info ^(/.+\.php)(/.*)?$
21819
21820
2182110.2. Default parameters
21822------------------------
21823
21824A Responder FastCGI application has the same purpose as a CGI/1.1 program. In
21825the CGI/1.1 specification (RFC3875), several variables must be passed to the
Ilya Shipitsin8525fd92020-02-29 12:34:59 +050021826script. So HAProxy set them and some others commonly used by FastCGI
Christopher Fauletb30b3102019-09-12 23:03:09 +020021827applications. All these variables may be overwritten, with caution though.
21828
21829 +-------------------+-----------------------------------------------------+
21830 | AUTH_TYPE | Identifies the mechanism, if any, used by HAProxy |
21831 | | to authenticate the user. Concretely, only the |
21832 | | BASIC authentication mechanism is supported. |
21833 | | |
21834 +-------------------+-----------------------------------------------------+
21835 | CONTENT_LENGTH | Contains the size of the message-body attached to |
21836 | | the request. It means only requests with a known |
21837 | | size are considered as valid and sent to the |
21838 | | application. |
21839 | | |
21840 +-------------------+-----------------------------------------------------+
21841 | CONTENT_TYPE | Contains the type of the message-body attached to |
21842 | | the request. It may not be set. |
21843 | | |
21844 +-------------------+-----------------------------------------------------+
21845 | DOCUMENT_ROOT | Contains the document root on the remote host under |
21846 | | which the script should be executed, as defined in |
21847 | | the application's configuration. |
21848 | | |
21849 +-------------------+-----------------------------------------------------+
21850 | GATEWAY_INTERFACE | Contains the dialect of CGI being used by HAProxy |
21851 | | to communicate with the FastCGI application. |
21852 | | Concretely, it is set to "CGI/1.1". |
21853 | | |
21854 +-------------------+-----------------------------------------------------+
21855 | PATH_INFO | Contains the portion of the URI path hierarchy |
21856 | | following the part that identifies the script |
21857 | | itself. To be set, the directive "path-info" must |
21858 | | be defined. |
21859 | | |
21860 +-------------------+-----------------------------------------------------+
21861 | PATH_TRANSLATED | If PATH_INFO is set, it is its translated version. |
21862 | | It is the concatenation of DOCUMENT_ROOT and |
21863 | | PATH_INFO. If PATH_INFO is not set, this parameters |
21864 | | is not set too. |
21865 | | |
21866 +-------------------+-----------------------------------------------------+
21867 | QUERY_STRING | Contains the request's query string. It may not be |
21868 | | set. |
21869 | | |
21870 +-------------------+-----------------------------------------------------+
21871 | REMOTE_ADDR | Contains the network address of the client sending |
21872 | | the request. |
21873 | | |
21874 +-------------------+-----------------------------------------------------+
21875 | REMOTE_USER | Contains the user identification string supplied by |
21876 | | client as part of user authentication. |
21877 | | |
21878 +-------------------+-----------------------------------------------------+
21879 | REQUEST_METHOD | Contains the method which should be used by the |
21880 | | script to process the request. |
21881 | | |
21882 +-------------------+-----------------------------------------------------+
21883 | REQUEST_URI | Contains the request's URI. |
21884 | | |
21885 +-------------------+-----------------------------------------------------+
21886 | SCRIPT_FILENAME | Contains the absolute pathname of the script. it is |
21887 | | the concatenation of DOCUMENT_ROOT and SCRIPT_NAME. |
21888 | | |
21889 +-------------------+-----------------------------------------------------+
21890 | SCRIPT_NAME | Contains the name of the script. If the directive |
21891 | | "path-info" is defined, it is the first part of the |
21892 | | URI path hierarchy, ending with the script name. |
21893 | | Otherwise, it is the entire URI path. |
21894 | | |
21895 +-------------------+-----------------------------------------------------+
21896 | SERVER_NAME | Contains the name of the server host to which the |
21897 | | client request is directed. It is the value of the |
21898 | | header "Host", if defined. Otherwise, the |
21899 | | destination address of the connection on the client |
21900 | | side. |
21901 | | |
21902 +-------------------+-----------------------------------------------------+
21903 | SERVER_PORT | Contains the destination TCP port of the connection |
21904 | | on the client side, which is the port the client |
21905 | | connected to. |
21906 | | |
21907 +-------------------+-----------------------------------------------------+
21908 | SERVER_PROTOCOL | Contains the request's protocol. |
21909 | | |
21910 +-------------------+-----------------------------------------------------+
Christopher Fauletb2a50292021-06-11 13:34:42 +020021911 | SERVER_SOFTWARE | Contains the string "HAProxy" followed by the |
21912 | | current HAProxy version. |
21913 | | |
21914 +-------------------+-----------------------------------------------------+
Christopher Fauletb30b3102019-09-12 23:03:09 +020021915 | HTTPS | Set to a non-empty value ("on") if the script was |
21916 | | queried through the HTTPS protocol. |
21917 | | |
21918 +-------------------+-----------------------------------------------------+
21919
21920
2192110.3. Limitations
21922------------------
21923
21924The current implementation have some limitations. The first one is about the
21925way some request headers are hidden to the FastCGI applications. This happens
21926during the headers analysis, on the backend side, before the connection
21927establishment. At this stage, HAProxy know the backend is using a FastCGI
21928application but it don't know if the request will be routed to a FastCGI server
21929or not. But to hide request headers, it simply removes them from the HTX
21930message. So, if the request is finally routed to an HTTP server, it never see
21931these headers. For this reason, it is not recommended to mix FastCGI servers
21932and HTTP servers under the same backend.
21933
21934Similarly, the rules "set-param" and "pass-header" are evaluated during the
21935request headers analysis. So the evaluation is always performed, even if the
21936requests is finally forwarded to an HTTP server.
21937
21938About the rules "set-param", when a rule is applied, a pseudo header is added
21939into the HTX message. So, the same way than for HTTP header rewrites, it may
21940fail if the buffer is full. The rules "set-param" will compete with
21941"http-request" ones.
21942
21943Finally, all FastCGI params and HTTP headers are sent into a unique record
21944FCGI_PARAM. Encoding of this record must be done in one pass, otherwise a
21945processing error is returned. It means the record FCGI_PARAM, once encoded,
21946must not exceeds the size of a buffer. However, there is no reserve to respect
21947here.
William Lallemand86d0df02017-11-24 21:36:45 +010021948
Emeric Brunce325c42021-04-02 17:05:09 +020021949
2195011. Address formats
21951-------------------
21952
21953Several statements as "bind, "server", "nameserver" and "log" requires an
21954address.
21955
21956This address can be a host name, an IPv4 address, an IPv6 address, or '*'.
21957The '*' is equal to the special address "0.0.0.0" and can be used, in the case
21958of "bind" or "dgram-bind" to listen on all IPv4 of the system.The IPv6
21959equivalent is '::'.
21960
21961Depending of the statement, a port or port range follows the IP address. This
21962is mandatory on 'bind' statement, optional on 'server'.
21963
21964This address can also begin with a slash '/'. It is considered as the "unix"
21965family, and '/' and following characters must be present the path.
21966
21967Default socket type or transport method "datagram" or "stream" depends on the
21968configuration statement showing the address. Indeed, 'bind' and 'server' will
21969use a "stream" socket type by default whereas 'log', 'nameserver' or
21970'dgram-bind' will use a "datagram".
21971
21972Optionally, a prefix could be used to force the address family and/or the
21973socket type and the transport method.
21974
21975
2197611.1 Address family prefixes
21977----------------------------
21978
21979'abns@<name>' following <name> is an abstract namespace (Linux only).
21980
21981'fd@<n>' following address is a file descriptor <n> inherited from the
21982 parent. The fd must be bound and may or may not already be
21983 listening.
21984
21985'ip@<address>[:port1[-port2]]' following <address> is considered as an IPv4 or
21986 IPv6 address depending on the syntax. Depending
21987 on the statement using this address, a port or
21988 a port range may or must be specified.
21989
21990'ipv4@<address>[:port1[-port2]]' following <address> is always considered as
21991 an IPv4 address. Depending on the statement
21992 using this address, a port or a port range
21993 may or must be specified.
21994
21995'ipv6@<address>[:port1[-port2]]' following <address> is always considered as
21996 an IPv6 address. Depending on the statement
21997 using this address, a port or a port range
21998 may or must be specified.
21999
22000'sockpair@<n>' following address is the file descriptor of a connected unix
22001 socket or of a socketpair. During a connection, the initiator
22002 creates a pair of connected sockets, and passes one of them
22003 over the FD to the other end. The listener waits to receive
22004 the FD from the unix socket and uses it as if it were the FD
22005 of an accept(). Should be used carefully.
22006
22007'unix@<path>' following string is considered as a UNIX socket <path>. this
22008 prefix is useful to declare an UNIX socket path which don't
22009 start by slash '/'.
22010
22011
2201211.2 Socket type prefixes
22013-------------------------
22014
22015Previous "Address family prefixes" can also be prefixed to force the socket
22016type and the transport method. The default depends of the statement using
22017this address but in some cases the user may force it to a different one.
22018This is the case for "log" statement where the default is syslog over UDP
22019but we could force to use syslog over TCP.
22020
22021Those prefixes were designed for internal purpose and users should
22022instead use aliases of the next section "11.5.3 Protocol prefixes".
22023
22024If users need one those prefixes to perform what they expect because
22025they can not configure the same using the protocol prefixes, they should
22026report this to the maintainers.
22027
22028'stream+<family>@<address>' forces socket type and transport method
22029 to "stream"
22030
22031'dgram+<family>@<address>' forces socket type and transport method
22032 to "datagram".
22033
22034
2203511.3 Protocol prefixes
22036----------------------
22037
22038'tcp@<address>[:port1[-port2]]' following <address> is considered as an IPv4
22039 or IPv6 address depending of the syntax but
22040 socket type and transport method is forced to
22041 "stream". Depending on the statement using
22042 this address, a port or a port range can or
22043 must be specified. It is considered as an alias
22044 of 'stream+ip@'.
22045
22046'tcp4@<address>[:port1[-port2]]' following <address> is always considered as
22047 an IPv4 address but socket type and transport
22048 method is forced to "stream". Depending on the
22049 statement using this address, a port or port
22050 range can or must be specified.
22051 It is considered as an alias of 'stream+ipv4@'.
22052
22053'tcp6@<address>[:port1[-port2]]' following <address> is always considered as
22054 an IPv6 address but socket type and transport
22055 method is forced to "stream". Depending on the
22056 statement using this address, a port or port
22057 range can or must be specified.
22058 It is considered as an alias of 'stream+ipv4@'.
22059
22060'udp@<address>[:port1[-port2]]' following <address> is considered as an IPv4
22061 or IPv6 address depending of the syntax but
22062 socket type and transport method is forced to
22063 "datagram". Depending on the statement using
22064 this address, a port or a port range can or
22065 must be specified. It is considered as an alias
22066 of 'dgram+ip@'.
22067
22068'udp4@<address>[:port1[-port2]]' following <address> is always considered as
22069 an IPv4 address but socket type and transport
22070 method is forced to "datagram". Depending on
22071 the statement using this address, a port or
22072 port range can or must be specified.
22073 It is considered as an alias of 'stream+ipv4@'.
22074
22075'udp6@<address>[:port1[-port2]]' following <address> is always considered as
22076 an IPv6 address but socket type and transport
22077 method is forced to "datagram". Depending on
22078 the statement using this address, a port or
22079 port range can or must be specified.
22080 It is considered as an alias of 'stream+ipv4@'.
22081
22082'uxdg@<path>' following string is considered as a unix socket <path> but
22083 transport method is forced to "datagram". It is considered as
22084 an alias of 'dgram+unix@'.
22085
22086'uxst@<path>' following string is considered as a unix socket <path> but
22087 transport method is forced to "stream". It is considered as
22088 an alias of 'stream+unix@'.
22089
22090In future versions, other prefixes could be used to specify protocols like
22091QUIC which proposes stream transport based on socket of type "datagram".
22092
Willy Tarreau0ba27502007-12-24 16:55:16 +010022093/*
22094 * Local variables:
22095 * fill-column: 79
22096 * End:
22097 */