How moving a FlexVol volume works

Cluster : Storage > Aggregates : Understanding aggregates : How moving a FlexVol volume works

FlexVol volumes are moved from one aggregate or node to another within the same Vserver for capacity utilization and improved performance, and to satisfy service-level agreements.

A volume move does not disrupt client access during the move.

Note: You cannot move 64-bit volumes to 32-bit aggregates.

Moving a volume occurs in multiple phases:

•	A new volume is made on the destination aggregate.

•	The data from the original volume is copied to the new volume.

During this time, the original volume is intact and available for clients to access.

•	At the end of the move process, client access is temporarily blocked.

During this time the system performs a final replication from the source volume to the destination volume, swaps the identities of the source and destination volumes, and changes the destination volume to the source volume.

•	After completing the move, the system routes client traffic to the new source volume and resumes client access.

The move is not disruptive to client access because the time in which client access is blocked ends before clients notice a disruption and time out. Client access is blocked for 45 seconds by default. If the volume move operation cannot finish in the time that access is denied, the system aborts this final phase of the volume move operation and allows client access. The system runs the final phase of the volume move operation until the volume move is complete or until the default maximum of three attempts is reached. If the volume move operation fails after the third attempt, the process goes into a cutover deferred state and waits for you to initiate the final phase.

You can change the amount of time client access is blocked or the number of times (cutover attempts) the final phase of the volume move operation is run if the defaults are not adequate. You can also determine what the system does if the volume move operation cannot be completed during the time client access is blocked. The volume move start man page contains details about moving a volume without disrupting client access.

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