Replacing a Failed Quorum Server System

When a quorum server fails or becomes unavailable to the clusters it is providing quorum services for, this will not cause a failure on any cluster. However, the loss of the quorum server does increase the vulnerability of the clusters in case there is an additional failure. Use the following procedure to replace a defective quorum server system. If you use this procedure, you do not need to change the configuration of any cluster nodes.

Remove the old quorum server system from the network.
Set up the new system and configure it with the old quorum server’s IP address and hostname.
Install and configure the quorum server software on the new system. Be sure to include in the new QS authorization file (/etc/cmcluster/qs_authfile) all of the nodes that were configured for the old quorum server. Refer to the qs(1) man page for details about configuring the QS authorization file.
Start the quorum server as follows:
- Edit the /etc/inittab file to add the quorum server entries.
- Use the init q command to run the quorum server.
Refer to the qs(1) man page for more details.
All nodes in all clusters that were using the old quorum server will connect to the new quorum server. Use the cmviewcl -v command from any cluster that is using the quorum server to verify that the nodes in that cluster have connected to the QS.
The quorum server log file on the new quorum server will show a log message like the following for each cluster that uses the quorum server:
Request for lock /sg/<ClusterName> succeeded. New lock owners: N1, N2
To check that the quorum server has been correctly configured and to verify the connectivity of a node to the quorum server, you can execute the following command from your cluster nodes as follows:
cmquerycl -q QSHostName -n Node1 -n Node2 ...
The command will output an error message if the specified nodes cannot communicate with the quorum server.




	NOTE: While the old quorum server is down and the new one is being set up, these things can happen: These three commands will not work: cmquerycl -q, cmapplyconf -C, and cmcheckconf -C If there is a node or network failure that creates a 50-50 membership split, the quorum server will not be available as a tie-breaker, and the cluster will fail. Make sure that the old Quorum Server system does not re-join the network with the old IP address.

Replacing a Failed Quorum Server System

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