Disaster recovery issues

As with any type of problem or failure, obtain the GPFS log files (mmfs.log.*) from all nodes in the cluster and, if available, the content of the internal dumps.

For more information, see:
The following two messages might appear in the GPFS log for active/active disaster recovery scenarios with GPFS replication. The purpose of these messages is to record quorum override decisions that are made after the loss of most of the disks:
6027-435 [N]
The file system descriptor quorum has been overridden.
6027-490 [N]
The descriptor replica on disk diskName has been excluded.
A message similar to these appear in the log on the file system manager, node every time it reads the file system descriptor with an overridden quorum: 
...
6027-435 [N] The file system descriptor quorum has been overridden.
6027-490 [N] The descriptor replica on disk gpfs23nsd has been excluded.
6027-490 [N] The descriptor replica on disk gpfs24nsd has been excluded.
...

For more information on node override, see Node failure.

For PPRC and FlashCopy®-based configurations, more problem determination information can be collected from the ESS log file. This information and the appropriate ESS documentation must be referred while working with various types disk subsystem-related failures. For instance, if users are unable to perform a PPRC failover (or failback) task successfully or unable to generate a FlashCopy of a disk volume, they should consult the subsystem log and the appropriate ESS documentation. For more information, see the following topics: