HP Serviceguard Quorum Server Version A.04.00 Release Notes, May 2014

IMPORTANT: Under certain conditions it is possible for quorum server to deny a lock to a node
that should be able to obtain if that node is a member of a cluster that previously shared a duplicate
name with another cluster and they both used the same quorum server. This can happen even if
the name conflict had been previously resolved by renaming one of the clusters.
The quorum server log looks similar to the following:
Nov 05 00:55:05:0:Request for lock /sg/CLUSTER_DEV succeeded. New lock
owners: node1,node2
Dec 16 10:27:39:0:Request for lock /sg/CLUSTER_DEV succeeded. New lock
owners: node3,node4
Now, if you delete the second cluster (that is, node3, node4) and rename it as CLUSTER_PROD,
the quorum server log shows the following:
Dec 16 10:47:01:0:Request for lock /sg/CLUSTER_PROD succeeded. New lock
owners: node3,node4
Now, node2 has a problem and CLUSTER_DEV reforms with node1 racing for the cluster lock.
The quorum server assumes CLUSTER_DEV members are node3 and node4 and therefore denies
the lock.
The quorum server log shows the following:
Jan 24 15:37:53:0:Request for lock /sg/CLUSTER_DEV from applicant node1
denied: lock owned by others.
node1 TOC's with the following sequence in syslog.log file:
Jan 24 15:37:53 node1 cmcld[13495]: Timed out unhealthy member(s)
Jan 24 15:37:53 node1 cmcld[13495]: Lost heartbeat to node2
Jan 24 15:37:53 node1 cmcld[13495]: Resolving quorum with members node2
Jan 24 15:37:53 node1 cmcld[13495]: Attempting to get quorum server
lock /sg/CLUSTER_DEV. Active
members:node1
Jan 24 15:37:53 node1 cmcld[13495]: Membership: membership at 1 is
REFORMING (coordinator 2)
includes: 2 excludes: 1
Jan 24 15:37:53 node1 cmcld[13495]: Attempt to get quorum server lock
/sg/CLUSTER_DEV at 10.0.0.1 failed. Lock denied
Jan 24 15:37:53 node1 cmcld[13495]: Deamon exiting as it lost the quorum.
To avoid the above descried problem, you must restart the quorum server:
/sbin/init q
This will cause all the clusters that use this quorum server to re-register with their current cluster
members and clear any potential duplicate entries.
There is a small window (a few seconds) while the quorum server re-spawns and reinitializes during
which it is unavailable to all its client clusters.
Memory and Disk Requirements
Memory: 7.0 MB
Disk space: 1 MB
Network Recommendations
• Ideally the Quorum Server and the cluster or clusters it serves must communicate over a subnet
that does not handle other traffic. (If you are using a version of Serviceguard that supports
8 HP Serviceguard Quorum Server Version A.04.00 Release Notes