Hello, It seems many have this problem. Is there any indication why this happens, or if somebody has time to fix it? My situation: Debian squeeze Mysql 5.1 MMM v. 2.2.1 Master/Master setup with one writer, no readers. We experienced the problem a couple of times, where mmm can't connect to mysql server, even though nagios can (from the same server). MMM log: 2011/07/12 01:53:34 WARN Check 'rep_threads' on 'db05' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:34 WARN Check 'rep_backlog' on 'db05' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:36 WARN Check 'rep_threads' on 'db06' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:36 WARN Check 'rep_backlog' on 'db06' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:52 ERROR Check 'mysql' on 'db05' has failed for 18 seconds! Message: ERROR: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:53 FATAL State of host 'db05' changed from ONLINE to HARD_OFFLINE (ping: OK, mysql: not OK) 2011/07/12 01:53:53 INFO Removing all roles from host 'db05': 2011/07/12 01:53:53 INFO Removed role 'writer(xx.xx.xx.xx)' from host 'db05' 2011/07/12 01:53:53 INFO Orphaned role 'writer(xx.xx.xx.xx)' has been assigned to 'db06' 2011/07/12 01:53:54 ERROR Check 'mysql' on 'db06' has failed for 18 seconds! Message: ERROR: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 01:53:57 FATAL State of host 'db06' changed from ONLINE to HARD_OFFLINE (ping: OK, mysql: not OK) 2011/07/12 01:53:57 INFO Removing all roles from host 'db06': 2011/07/12 01:53:57 INFO Removed role 'writer(xx.xx.xx.xx)' from host 'db06' 2011/07/12 02:02:32 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:02:32 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:03:14 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:03:31 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:03:53 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:04:02 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:04:07 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:07:30 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:07:47 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:08:04 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:08:21 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:08:43 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:09:05 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:09:17 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:09:34 WARN Check 'mysql' on 'db06' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:09:51 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:10:08 WARN Check 'mysql' on 'db05' is in unknown state! Message: UNKNOWN: Too many connections! Too many connections 2011/07/12 02:10:13 INFO Check 'rep_backlog' on 'db05' is ok! 2011/07/12 02:10:13 INFO Check 'rep_threads' on 'db05' is ok! 2011/07/12 02:10:13 INFO Check 'mysql' on 'db05' is ok! 2011/07/12 02:10:14 FATAL State of host 'db05' changed from HARD_OFFLINE to AWAITING_RECOVERY 2011/07/12 02:10:18 INFO Check 'rep_backlog' on 'db06' is ok! 2011/07/12 02:10:18 INFO Check 'rep_threads' on 'db06' is ok! 2011/07/12 02:10:18 INFO Check 'mysql' on 'db06' is ok! 2011/07/12 02:10:20 FATAL State of host 'db06' changed from HARD_OFFLINE to AWAITING_RECOVERY 2011/07/12 02:13:05 WARN Check 'rep_threads' on 'db05' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:05 WARN Check 'rep_backlog' on 'db05' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:07 WARN Check 'rep_backlog' on 'db06' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:07 WARN Check 'rep_threads' on 'db06' is in unknown state! Message: UNKNOWN: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:23 ERROR Check 'mysql' on 'db05' has failed for 18 seconds! Message: ERROR: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:25 FATAL State of host 'db05' changed from AWAITING_RECOVERY to HARD_OFFLINE 2011/07/12 02:13:25 ERROR Check 'mysql' on 'db06' has failed for 18 seconds! Message: ERROR: Connect error (host = xx.xx.xx.xx:3306, user = mmm_monitor)! Can't connect to MySQL server on 'xx.xx.xx.xx' (4) 2011/07/12 02:13:28 FATAL State of host 'db06' changed from AWAITING_RECOVERY to HARD_OFFLINE 2011/07/12 02:18:03 INFO Check 'mysql' on 'db06' is ok! 2011/07/12 02:18:03 INFO Check 'rep_threads' on 'db06' is ok! 2011/07/12 02:18:03 INFO Check 'rep_backlog' on 'db06' is ok! 2011/07/12 02:18:06 FATAL State of host 'db06' changed from HARD_OFFLINE to AWAITING_RECOVERY 2011/07/12 02:18:08 INFO Check 'mysql' on 'db05' is ok! 2011/07/12 02:18:08 INFO Check 'rep_threads' on 'db05' is ok! 2011/07/12 02:18:08 INFO Check 'rep_backlog' on 'db05' is ok! 2011/07/12 02:18:09 FATAL State of host 'db05' changed from HARD_OFFLINE to AWAITING_RECOVERY 2011/07/12 03:00:14 FATAL Admin changed state of 'db05' from AWAITING_RECOVERY to ONLINE 2011/07/12 03:00:14 INFO Orphaned role 'writer(xx.xx.xx.xx)' has been assigned to 'db05' 2011/07/12 03:00:29 FATAL Admin changed state of 'db06' from AWAITING_RECOVERY to ONLINE Mysql process list while too many connections: Id User Host db Command Time State Info 1 system user NULL Connect 483380 Has read all relay log; waiting for the slave I/O thread to update it NULL 2 system user NULL Connect 484032 Waiting for master to send event NULL 466026 unauthenticated user monitorHost:52546 NULL Connect NULL login NULL 466027 unauthenticated user monitorHost:52564 NULL Connect NULL login NULL 466028 unauthenticated user monitorHost:52565 NULL Connect NULL login NULL 466029 unauthenticated user monitorHost:52566 NULL Connect NULL login NULL 466030 unauthenticated user monitorHost:52581 NULL Connect NULL login NULL 466031 unauthenticated user monitorHost:52582 NULL Connect NULL login NULL 466032 unauthenticated user monitorHost:52583 NULL Connect NULL login NULL 466033 unauthenticated user monitorHost:52599 NULL Connect NULL login NULL 466034 unauthenticated user monitorHost:52600 NULL Connect NULL login NULL 466035 unauthenticated user monitorHost:52602 NULL Connect NULL login NULL 466036 unauthenticated user monitorHost:52618 NULL Connect NULL login NULL 466037 unauthenticated user monitorHost:52619 NULL Connect NULL login NULL 466038 unauthenticated user monitorHost:52620 NULL Connect NULL login NULL 466039 unauthenticated user monitorHost:52634 NULL Connect NULL login NULL 466040 unauthenticated user monitorHost:52635 NULL Connect NULL login NULL 466041 unauthenticated user monitorHost:52636 NULL Connect NULL login NULL 466042 unauthenticated user monitorHost:52652 NULL Connect NULL login NULL 466043 unauthenticated user monitorHost:52651 NULL Connect NULL login NULL 466044 unauthenticated user monitorHost:52654 NULL Connect NULL login NULL 466045 unauthenticated user monitorHost:52665 NULL Connect NULL login NULL 466046 unauthenticated user monitorHost:52666 NULL Connect NULL login NULL 466047 unauthenticated user monitorHost:52668 NULL Connect NULL login NULL 466049 unauthenticated user monitorHost:52685 NULL Connect NULL login NULL 466050 unauthenticated user monitorHost:52687 NULL Connect NULL login NULL 466051 unauthenticated user monitorHost:52686 NULL Connect NULL login NULL 466052 unauthenticated user monitorHost:52702 NULL Connect NULL login NULL 466053 unauthenticated user monitorHost:52703 NULL Connect NULL login NULL 466054 unauthenticated user monitorHost:52704 NULL Connect NULL login NULL 466055 unauthenticated user monitorHost:52722 NULL Connect NULL login NULL 466056 unauthenticated user monitorHost:52723 NULL Connect NULL login NULL 466057 unauthenticated user monitorHost:52724 NULL Connect NULL login NULL 466058 unauthenticated user monitorHost:52736 NULL Connect NULL login NULL 466059 unauthenticated user monitorHost:52737 NULL Connect NULL login NULL 466060 unauthenticated user monitorHost:52738 NULL Connect NULL login NULL 466061 unauthenticated user monitorHost:52756 NULL Connect NULL login NULL 466062 unauthenticated user monitorHost:52757 NULL Connect NULL login NULL 466063 unauthenticated user monitorHost:52758 NULL Connect NULL login NULL 466064 unauthenticated user monitorHost:52773 NULL Connect NULL login NULL 466065 unauthenticated user monitorHost:52774 NULL Connect NULL login NULL 466066 unauthenticated user monitorHost:52775 NULL Connect NULL login NULL 466067 unauthenticated user monitorHost:52793 NULL Connect NULL login NULL 466068 unauthenticated user monitorHost:52794 NULL Connect NULL login NULL 466069 unauthenticated user monitorHost:52795 NULL Connect NULL login NULL 466070 unauthenticated user monitorHost:52811 NULL Connect NULL login NULL 466071 unauthenticated user monitorHost:52812 NULL Connect NULL login NULL 466072 unauthenticated user monitorHost:52813 NULL Connect NULL login NULL 466073 unauthenticated user monitorHost:52830 NULL Connect NULL login NULL 466074 unauthenticated user monitorHost:52831 NULL Connect NULL login NULL 466075 unauthenticated user monitorHost:52833 NULL Connect NULL login NULL 466076 unauthenticated user monitorHost:52847 NULL Connect NULL login NULL 466077 unauthenticated user monitorHost:52848 NULL Connect NULL login NULL 466078 unauthenticated user monitorHost:52849 NULL Connect NULL login NULL 466079 unauthenticated user monitorHost:52865 NULL Connect NULL login NULL 466080 unauthenticated user monitorHost:52866 NULL Connect NULL login NULL 466081 unauthenticated user monitorHost:52867 NULL Connect NULL login NULL 466082 replication db06:50483 NULL Binlog Dump 201 Has sent all binlog to slave; waiting for binlog to be updated NULL 466083 unauthenticated user monitorHost:52877 NULL Connect NULL login NULL 466084 unauthenticated user monitorHost:52878 NULL Connect NULL login NULL 466085 unauthenticated user monitorHost:52879 NULL Connect NULL login NULL 466086 unauthenticated user monitorHost:52905 NULL Connect NULL login NULL 466087 unauthenticated user monitorHost:52906 NULL Connect NULL login NULL 466088 unauthenticated user monitorHost:52907 NULL Connect NULL login NULL 466089 unauthenticated user monitorHost:52922 NULL Connect NULL login NULL 466090 unauthenticated user monitorHost:52923 NULL Connect NULL login NULL 466091 unauthenticated user monitorHost:52924 NULL Connect NULL login NULL 466092 unauthenticated user monitorHost:52941 NULL Connect NULL login NULL 466093 unauthenticated user monitorHost:52942 NULL Connect NULL login NULL 466094 unauthenticated user monitorHost:52943 NULL Connect NULL login NULL 466095 unauthenticated user monitorHost:52957 NULL Connect NULL login NULL 466096 unauthenticated user monitorHost:52958 NULL Connect NULL login NULL 466097 unauthenticated user monitorHost:52959 NULL Connect NULL login NULL 466098 unauthenticated user monitorHost:52978 NULL Connect NULL login NULL 466099 unauthenticated user monitorHost:52979 NULL Connect NULL login NULL 466100 unauthenticated user monitorHost:52980 NULL Connect NULL login NULL 466101 unauthenticated user monitorHost:52991 NULL Connect NULL login NULL 466102 unauthenticated user monitorHost:52992 NULL Connect NULL login NULL 466103 unauthenticated user monitorHost:52993 NULL Connect NULL login NULL 466104 unauthenticated user monitorHost:53004 NULL Connect NULL login NULL 466105 unauthenticated user monitorHost:53005 NULL Connect NULL login NULL 466106 unauthenticated user monitorHost:53006 NULL Connect NULL login NULL 466107 unauthenticated user monitorHost:53039 NULL Connect NULL login NULL 466108 unauthenticated user monitorHost:53040 NULL Connect NULL login NULL 466109 unauthenticated user monitorHost:53041 NULL Connect NULL login NULL 466110 unauthenticated user monitorHost:53060 NULL Connect NULL login NULL 466111 unauthenticated user monitorHost:53061 NULL Connect NULL login NULL 466112 unauthenticated user monitorHost:53062 NULL Connect NULL login NULL 466113 unauthenticated user monitorHost:53074 NULL Connect NULL login NULL 466114 unauthenticated user monitorHost:53075 NULL Connect NULL login NULL 466115 unauthenticated user monitorHost:53076 NULL Connect NULL login NULL 466116 unauthenticated user monitorHost:53090 NULL Connect NULL login NULL 466117 unauthenticated user monitorHost:53091 NULL Connect NULL login NULL 466118 unauthenticated user monitorHost:53092 NULL Connect NULL login NULL 466120 unauthenticated user monitorHost:46147 NULL Connect NULL login NULL 466121 unauthenticated user monitorHost:46148 NULL Connect NULL login NULL 466122 unauthenticated user monitorHost:46149 NULL Connect NULL login NULL 466123 unauthenticated user monitorHost:46165 NULL Connect NULL login NULL 466124 unauthenticated user monitorHost:46166 NULL Connect NULL login NULL 466125 unauthenticated user monitorHost:46167 NULL Connect NULL login NULL 466126 unauthenticated user monitorHost:46182 NULL Connect NULL login NULL 466127 unauthenticated user monitorHost:46183 NULL Connect NULL login NULL 466128 unauthenticated user monitorHost:46184 NULL Connect NULL login NULL 466129 unauthenticated user monitorHost:46203 NULL Connect NULL login NULL 466130 unauthenticated user monitorHost:46204 NULL Connect NULL login NULL 466131 unauthenticated user monitorHost:46205 NULL Connect NULL login NULL 466132 unauthenticated user monitorHost:46219 NULL Connect NULL login NULL 466133 unauthenticated user monitorHost:46220 NULL Connect NULL login NULL 466134 unauthenticated user monitorHost:46221 NULL Connect NULL login NULL 466135 unauthenticated user monitorHost:46237 NULL Connect NULL login NULL 466136 unauthenticated user monitorHost:46238 NULL Connect NULL login NULL 466137 unauthenticated user monitorHost:46239 NULL Connect NULL login NULL 466138 unauthenticated user monitorHost:46255 NULL Connect NULL login NULL 466139 unauthenticated user monitorHost:46256 NULL Connect NULL login NULL 466140 unauthenticated user monitorHost:46257 NULL Connect NULL login NULL 466141 unauthenticated user monitorHost:46270 NULL Connect NULL login NULL 466142 unauthenticated user monitorHost:46271 NULL Connect NULL login NULL 466143 unauthenticated user monitorHost:46272 NULL Connect NULL login NULL 466144 unauthenticated user monitorHost:46288 NULL Connect NULL login NULL 466145 unauthenticated user monitorHost:46289 NULL Connect NULL login NULL 466146 unauthenticated user monitorHost:46290 NULL Connect NULL login NULL 466147 unauthenticated user monitorHost:46302 NULL Connect NULL login NULL 466148 unauthenticated user monitorHost:46303 NULL Connect NULL login NULL 466149 unauthenticated user monitorHost:46304 NULL Connect NULL login NULL 466151 debian-sys-maint localhost:51494 NULL Query 0 NULL show processlist Any help or ideas are greatly appreciated. Thanks ;-)