MAJOR: check: find out which port to use for health check at run time
HAProxy used to deduce port used for health checks when parsing configuration
at startup time.
Because of this way of working, it makes it complicated to change the port at
run time.
The current patch changes this behavior and makes HAProxy to choose the
port used for health checking when preparing the check task itself.
A new type of error is introduced and reported when no port can be found.
There won't be any impact on performance, since the process to find out the
port value is made of a few 'if' statements.
This patch also introduces a new check state CHK_ST_PORT_MISS: this flag is
used to report an error in the case when HAProxy needs to establish a TCP
connection to a server, to perform a health check but no TCP ports can be
found for it.
And last, it also introduces a new stream termination condition:
SF_ERR_CHK_PORT. Purpose of this flag is to report an error in the event when
HAProxy has to run a health check but no port can be found to perform it.
diff --git a/src/checks.c b/src/checks.c
index 5d02642..65d0037 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -679,6 +679,12 @@
}
}
+ if (check->state & CHK_ST_PORT_MISS) {
+ /* NOTE: this is reported after <fall> tries */
+ chunk_printf(chk, "No port available for the TCP connection");
+ set_server_check_status(check, HCHK_STATUS_SOCKERR, err_msg);
+ }
+
if ((conn->flags & (CO_FL_CONNECTED|CO_FL_WAIT_L4_CONN)) == CO_FL_WAIT_L4_CONN) {
/* L4 not established (yet) */
if (conn->flags & CO_FL_ERROR)
@@ -1430,6 +1436,7 @@
* - SF_ERR_PRXCOND if the connection has been limited by the proxy (maxconn)
* - SF_ERR_RESOURCE if a system resource is lacking (eg: fd limits, ports, ...)
* - SF_ERR_INTERNAL for any other purely internal errors
+ * - SF_ERR_CHK_PORT if no port could be found to run a health check on an AF_INET* socket
* Additionnally, in the case of SF_ERR_RESOURCE, an emergency log will be emitted.
* Note that we try to prevent the network stack from sending the ACK during the
* connect() when a pure TCP check is used (without PROXY protocol).
@@ -1491,8 +1498,16 @@
conn->addr.to = s->addr;
}
+ if ((conn->addr.to.ss_family == AF_INET) || (conn->addr.to.ss_family == AF_INET6)) {
+ int i = 0;
+
+ i = srv_check_healthcheck_port(check);
+ if (i == 0) {
+ conn->owner = check;
+ return SF_ERR_CHK_PORT;
+ }
+
- if (check->port) {
- set_host_port(&conn->addr.to, check->port);
+ set_host_port(&conn->addr.to, i);
}
proto = protocol_by_family(conn->addr.to.ss_family);
@@ -2072,6 +2087,9 @@
conn->flags |= CO_FL_ERROR;
chk_report_conn_err(conn, errno, 0);
break;
+ /* should share same code than cases below */
+ case SF_ERR_CHK_PORT:
+ check->state |= CHK_ST_PORT_MISS;
case SF_ERR_PRXCOND:
case SF_ERR_RESOURCE:
case SF_ERR_INTERNAL:
@@ -3368,6 +3386,53 @@
enqueue_email_alert(p, buf);
}
+/*
+ * Return value:
+ * the port to be used for the health check
+ * 0 in case no port could be found for the check
+ */
+int srv_check_healthcheck_port(struct check *chk)
+{
+ int i = 0;
+ struct server *srv = NULL;
+
+ srv = chk->server;
+
+ /* If neither a port nor an addr was specified and no check transport
+ * layer is forced, then the transport layer used by the checks is the
+ * same as for the production traffic. Otherwise we use raw_sock by
+ * default, unless one is specified.
+ */
+ if (!chk->port && !is_addr(&chk->addr)) {
+#ifdef USE_OPENSSL
+ chk->use_ssl |= (srv->use_ssl || (srv->proxy->options & PR_O_TCPCHK_SSL));
+#endif
+ chk->send_proxy |= (srv->pp_opts);
+ }
+
+ /* by default, we use the health check port ocnfigured */
+ if (chk->port > 0)
+ return chk->port;
+
+ /* try to get the port from check_core.addr if check.port not set */
+ i = get_host_port(&chk->addr);
+ if (i > 0)
+ return i;
+
+ /* try to get the port from server address */
+ /* prevent MAPPORTS from working at this point, since checks could
+ * not be performed in such case (MAPPORTS impose a relative ports
+ * based on live traffic)
+ */
+ if (srv->flags & SRV_F_MAPPORTS)
+ return 0;
+ i = get_host_port(&srv->addr); /* by default */
+ if (i > 0)
+ return i;
+
+ return 0;
+}
+
/*
* Local variables: