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shuts down a degraded MDC and then reboots it so that, on recovery, it
becomes the standby MDC in the event future MDC failover is required.
While other methods of failover are available, such as quorums,
STONITH is the only widely acknowledged method of reliable failover
control - especially for software that runs on multiple operating systems.
Without STONITH, there is the possibility that a damaged MDC could
continue acting as the primary MDC and attempt to handle client IO
requests or move data between storage tiers. For shared file systems
STONITH is especially critical because a MDC controls access for
multiple hosts reading and writing to a single volume - and potentially
the same file.
Currently MDC failover is only supported when configured by Quantum
Solutions Engineering staff.