Disaster recovery using volume SnapMirror on NearStore storage systems

You can use NetBackup and NetApp volume SnapMirror technology to provide a disaster recovery solution for Disk Storage Units (DSUs).

SnapVault for NetBackup with volume SnapMirror provides disaster recovery in a very efficient manner. Deduplicated volume blocks are sent only once over wire from the SnapMirror source to the SnapMirror destination, and deduplication properties from the source are preserved on the destination.

To provide failover support in a disaster recovery (DR) situation using the volume SnapMirror feature outside of the purview of NetBackup, you need to replicate the DSUs from one NearStore storage system (SystemA) to a second NearStore storage system (SystemB). In the case of a failure where the volumes on SystemA are unrecoverable (that is, when either the entire SystemA storage system is down or when volumes on SystemA are destroyed and cannot be recovered), you need to manually break the SnapMirror relationship, which enables the replicated volumes on SystemB for read and write access. Only those volumes that are replicated can be recovered. After a few configuration adjustments in NetBackup, all future backups and restores to the volumes that were replicated can now be served by SystemB.

You can subsequently reconfigure NetBackup to direct restores, verifications, deletions and backups back to SystemA. Your disaster recovery plan should include NetBackup catalog backup and restore procedures. For more information regarding catalog backup and restore, see the NetBackup Administrators Guide.

• Configuring SnapVault for NetBackup with NetApp volume SnapMirror
  To set up a disaster recovery solution for SnapVault for NetBackup using volume SnapMirror, you need to configure volume SnapMirror relationships for the DSUs to be protected on the NearStore storage systems.
• Actions required in the event of a NearStore storage system failure
  In the event that SystemA becomes unavailable, the backup administrator must manually break the applicable SnapMirror relationships on SystemA and then make a few configuration adjustments in NetBackup to allow NetBackup to fail over from volumes on SystemA to volumes on SystemA.
• Returning to the initial setup after the failed system has recovered
  When SystemA is backed up, you can again adjust NetBackup settings and SnapMirror relationships on the NearStore storage systems to reinstate the initial configuration on which NetBackup sends backups to volumes on SystemA. These volumes are replicated to SystemB.
• Use cases of the commands used in the failover process
  The following use cases are based on this representative environment: Two media servers (mediaserver1 and mediaserver2), that back up to volumes on a NearStore storage system (SystemA). SystemA contains volumes that are replicated, using SnapMirror, to another NearStore (SystemB). Mediaserver1 is backing up to volume1 on SystemA, and mediaserver2 is backing up to volume2 on SystemA.