From 9b2209a8d19cbdc815e398468b62d32373ee3bd2 Mon Sep 17 00:00:00 2001
From: Markus Makela <markus.makela@mariadb.com>
Date: Thu, 6 Oct 2016 16:52:50 +0300
Subject: [PATCH] Log only one warning when failover is initiated

Mysqlmon would log a warning at every monitoring interval when failover
was initiated.
---
 server/modules/monitor/mysqlmon.h           | 1 +
 server/modules/monitor/mysqlmon/mysql_mon.c | 8 +++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/server/modules/monitor/mysqlmon.h b/server/modules/monitor/mysqlmon.h
index 3eb551ccc..efbd140f3 100644
--- a/server/modules/monitor/mysqlmon.h
+++ b/server/modules/monitor/mysqlmon.h
@@ -77,6 +77,7 @@ typedef struct
     bool failover; /**< If simple failover is enabled */
     int failcount; /**< How many monitoring cycles servers must be
                                    down before failover is initiated */
+    bool warn_failover; /**< Log a warning when failover happens */
 } MYSQL_MONITOR;
 
 #endif
diff --git a/server/modules/monitor/mysqlmon/mysql_mon.c b/server/modules/monitor/mysqlmon/mysql_mon.c
index eaacaf1bb..f454ae84f 100644
--- a/server/modules/monitor/mysqlmon/mysql_mon.c
+++ b/server/modules/monitor/mysqlmon/mysql_mon.c
@@ -275,6 +275,7 @@ startMonitor(MONITOR *monitor, const CONFIG_PARAMETER* params)
         handle->mysql51_replication = false;
         handle->failover = false;
         handle->failcount = MYSQLMON_DEFAULT_FAILCOUNT;
+        handle->warn_failover = true;
         memset(handle->events, false, sizeof(handle->events));
         spinlock_init(&handle->lock);
     }
@@ -1093,11 +1094,12 @@ void do_failover(MYSQL_MONITOR *handle, MONITOR_SERVERS *db)
     {
         if (SERVER_IS_RUNNING(db->server))
         {
-            if (!SERVER_IS_MASTER(db->server))
+            if (!SERVER_IS_MASTER(db->server) && handle->warn_failover)
             {
                 MXS_WARNING("Failover initiated, server '%s' is now the master. "
                             "All other servers are set into maintenance mode.",
                             db->server->unique_name);
+                handle->warn_failover = false;
             }
 
             server_clear_set_status(db->server, SERVER_SLAVE, SERVER_MASTER);
@@ -1397,6 +1399,10 @@ monitorMain(void *arg)
                 /** Other servers have died, initiate a failover to the last remaining server */
                 do_failover(handle, mon->databases);
             }
+            else
+            {
+                handle->warn_failover = true;
+            }
         }
 
         ptr = mon->databases;