PRIMECLUSTER Global File Services Configuration and Administration Guide 4.2 (Solaris(TM) Operating Environment)

14.1.3 Automatic recovery in case primary MDS goes down during primary MDS operation only

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.

1. Restarting the failed MDS

   The failed MDS is restarted as the primary MDS.

2. Replaying the update log

   The new primary MDS replays the update log to ensure the consistency of the file system.

3. Resuming processing after MDS switching

   The AC makes a processing request to the new primary MDS.
   

Automatic recovery by standby MDS node

MDS normally operates on the predefined primary MDS node and secondary MDS node. By setting a standby MDS node (i.e., MDS node other than primary or secondary MDS node), however, the number of nodes on which MDS can operate can be increased.

If the primary MDS node or secondary MDS node, or both are not activated after the specified time, the standby MDS node activates MDS instead of the primary MDS node or secondary MDS node.

MDS operation is required for accessing a file system and increasing the number of MDS nodes is advantageous to ensure continued file system operation.

For details on the MDS node settings, see Section 15.2.2 "Node layout."