MEDIUM: server: implement TCP_USER_TIMEOUT on the server
This is equivalent to commit 2af207a ("MEDIUM: tcp: implement tcp-ut
bind option to set TCP_USER_TIMEOUT") except that this time it works
on the server side. The purpose is to detect dead server connections
even when checks are rare, disabled, or after a soft reload (since
checks are disabled there as well), and to ensure client connections
will get killed faster.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index b34a80c..c6219d2 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -10598,6 +10598,21 @@
Supported in default-server: No
+tcp-ut <delay>
+ Sets the TCP User Timeout for all outgoing connections to this server. This
+ option is available on Linux since version 2.6.37. It allows haproxy to
+ configure a timeout for sockets which contain data not receiving an
+ acknoledgement for the configured delay. This is especially useful on
+ long-lived connections experiencing long idle periods such as remote
+ terminals or database connection pools, where the client and server timeouts
+ must remain high to allow a long period of idle, but where it is important to
+ detect that the server has disappeared in order to release all resources
+ associated with its connection (and the client's session). One typical use
+ case is also to force dead server connections to die when health checks are
+ too slow or during a soft reload since health checks are then disabled. The
+ argument is a delay expressed in milliseconds by default. This only works for
+ regular TCP connections, and is ignored for other protocols.
+
track [<proxy>/]<server>
This option enables ability to set the current state of the server by tracking
another one. It is possible to track a server which itself tracks another
diff --git a/include/types/server.h b/include/types/server.h
index abd1130..3e25c34 100644
--- a/include/types/server.h
+++ b/include/types/server.h
@@ -216,6 +216,7 @@
time_t last_change; /* last time, when the state was changed */
int puid; /* proxy-unique server ID, used for SNMP, and "first" LB algo */
+ int tcp_ut; /* for TCP, user timeout */
struct check check; /* health-check specific configuration */
struct check agent; /* agent specific configuration */
diff --git a/src/proto_tcp.c b/src/proto_tcp.c
index df10ccb..cce0acb 100644
--- a/src/proto_tcp.c
+++ b/src/proto_tcp.c
@@ -39,7 +39,6 @@
#include <types/global.h>
#include <types/capture.h>
-#include <types/server.h>
#include <types/connection.h>
#include <proto/acl.h>
@@ -56,6 +55,7 @@
#include <proto/proto_tcp.h>
#include <proto/proxy.h>
#include <proto/sample.h>
+#include <proto/server.h>
#include <proto/stream.h>
#include <proto/stick_table.h>
#include <proto/stream_interface.h>
@@ -500,6 +500,11 @@
setsockopt(fd, IPPROTO_TCP, TCP_QUICKACK, &zero, sizeof(zero));
#endif
+#ifdef TCP_USER_TIMEOUT
+ /* there is not much more we can do here when it fails, it's still minor */
+ if (srv && srv->tcp_ut)
+ setsockopt(fd, IPPROTO_TCP, TCP_USER_TIMEOUT, &srv->tcp_ut, sizeof(srv->tcp_ut));
+#endif
if (global.tune.server_sndbuf)
setsockopt(fd, SOL_SOCKET, SO_SNDBUF, &global.tune.server_sndbuf, sizeof(global.tune.server_sndbuf));
@@ -2310,6 +2315,31 @@
}
#endif
+#ifdef TCP_USER_TIMEOUT
+/* parse the "tcp-ut" server keyword */
+static int srv_parse_tcp_ut(char **args, int *cur_arg, struct proxy *px, struct server *newsrv, char **err)
+{
+ const char *ptr = NULL;
+ unsigned int timeout;
+
+ if (!*args[*cur_arg + 1]) {
+ memprintf(err, "'%s' : missing TCP User Timeout value", args[*cur_arg]);
+ return ERR_ALERT | ERR_FATAL;
+ }
+
+ ptr = parse_time_err(args[*cur_arg + 1], &timeout, TIME_UNIT_MS);
+ if (ptr) {
+ memprintf(err, "'%s' : expects a positive delay in milliseconds", args[*cur_arg]);
+ return ERR_ALERT | ERR_FATAL;
+ }
+
+ if (newsrv->addr.ss_family == AF_INET || newsrv->addr.ss_family == AF_INET6)
+ newsrv->tcp_ut = timeout;
+
+ return 0;
+}
+#endif
+
static struct cfg_kw_list cfg_kws = {ILH, {
{ CFG_LISTEN, "tcp-request", tcp_parse_tcp_req },
{ CFG_LISTEN, "tcp-response", tcp_parse_tcp_rep },
@@ -2385,6 +2415,12 @@
{ NULL, NULL, 0 },
}};
+static struct srv_kw_list srv_kws = { "TCP", { }, {
+#ifdef TCP_USER_TIMEOUT
+ { "tcp-ut", srv_parse_tcp_ut, 1, 0 }, /* set TCP user timeout on server */
+#endif
+ { NULL, NULL, 0 },
+}};
static struct action_kw_list tcp_req_conn_actions = {ILH, {
{ "silent-drop", tcp_parse_silent_drop },
@@ -2421,6 +2457,7 @@
cfg_register_keywords(&cfg_kws);
acl_register_keywords(&acl_kws);
bind_register_keywords(&bind_kws);
+ srv_register_keywords(&srv_kws);
tcp_req_conn_keywords_register(&tcp_req_conn_actions);
tcp_req_cont_keywords_register(&tcp_req_cont_actions);
tcp_res_cont_keywords_register(&tcp_res_cont_actions);