If the primary MDS goes down in a state in which the MDS nodes are degraded only during primary MDS operation, the following processing is performed automatically.
Restarting the failed MDS
The MDS is started as the primary MDS again.
Replaying the update log
The new primary MDS replays the update log to ensure the consistency of the file system.
Resuming processing after MDS switching
The AC makes a processing request to the new primary MDS.