Volume sets in VVR

Volume Replicator supports replication for volume sets. Volume sets are an enhancement to VxVM that allow several volumes to be represented by a single logical object. All I/O from and to the underlying volumes is directed via the I/O interfaces of the volume set. The volume set feature supports the multi-device enhancement to Veritas File System (VxFS). This feature allows file systems to make best use of the different performance and availability characteristics of the underlying volumes. For example, metadata for a file system could be stored on volumes with higher redundancy, and user data on volumes with better performance.

VVR also supports replication for volume sets with SmartTier or Sub-file SmartTier.

In previous releases of VVR, component volumes of a volume set could be associated to an RVG. The individual component volumes were replicated to the Secondary. Now, VVR supports associating a volume set to an RDS, and replicating the component volumes. When a volume set is associated with an RVG, VVR internally associates all the component volumes to the RVG. A component volume can later be explicitly disassociated from the RVG; however, a volume should only be excluded from the RVG if it is not important for the application.

After the volume set is associated with an RVG, replicating that RVG replicates all the component volumes. If a Primary RVG contains one or more volume sets, the Secondary RVG must have the corresponding volume sets. The volume sets on the Secondary RVG must have at least the same component volumes as the Primary RVG.

The volumes in a volume set that is associated with an RVG are treated like any other volume in the RVG for all operational purposes. That is, any operation on the RVG that operates on the volumes includes the volumes that are part of associated volume sets.