Sometimes when using Pacemaker/Corosync-based cluster you can see warning message in crm_mon output:

Failed actions:
drbd_mysql:0_promote_0 (node=node2.cluster.org, call=11, rc=-2, status=Timed Out): unknown exec error

To clean it up you can use command crm_resource which checks health of resources:

[root@node1 ~]# crm_resource -P
Waiting for 1 replies from the CRMd. OK
[root@node1 ~]#

To check cluster’s status run crm_mon again, warning message should be gone.