NetWorker 19.7 Snapshot Management Integration Guide

Types of supported mirror devices

NetWorker supports the following types of mirror devices on VMAX storage arrays:

• TimeFinder BCV—These devices are full physical copies and appear as mirrors of the standard device.
• TimeFinder Snap/VDEV—These devices use the copy-on-write (COW) snapshot creation method.
• TimeFinder Clone—These devices create high performance, full source copies. The following limitations apply for rollback operations that use TimeFinder Clone copies:
  • Rollback operations fail for a snapshot that is created with the application variable SYMM_CLONE_FULL_COPY=FALSE.
  • Rollback operations fail for a source LUN that has another established BCV mirror unless you set SYMM_RB_OVERRIDE_OTHER_TGTS=TRUE.
  • Rollback operations fail for a source LUN that has an active relationship with more than one snapshot or mirror.

  Application Information variables for VMAX arrays provides details.

• TimeFinder VP Snap—These devices create space-efficient snapshots for virtual thin pool devices. The following limitations apply:
  • All VP Snap target devices that are paired to the same source LUN must be bound to the same thin pool.
  • A source device cannot simultaneously run both a VP Snap session and a Clone No Full Copy session.
• TimeFinder SnapVX—These devices are a fundamentally new TimeFinder, with snapshots now existing as pointers rather than as physical devices:
  • You need not specify a target device and the source and target pairs.
  • When you perform a rollback with SnapVX snapshots, the snapshot is not deleted from the NetWorker media database and is available again for subsequent rollback operations.
  • SnapVX only supports target LUN selection using Intelligent Pairing. If a symm.res is used the selection is ignored.