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Understanding SnapMirror volume replication

Traditionally, ONTAP replication technologies served the need for disaster recovery (DR) and data archiving. These technologies are combined in a way that allows you to configure disaster recovery and archiving on the same destination volume.

  • Asynchronous SnapMirror disaster recovery basics
    SnapMirror is disaster recovery technology, designed for failover from primary storage to secondary storage at a geographically remote site. As its name implies, SnapMirror creates a replica, or mirror, of your working data in secondary storage from which you can continue to serve data in the event of a catastrophe at the primary site.
  • SnapMirror Synchronous disaster recovery basics
    Beginning with ONTAP 9.5, SnapMirror Synchronous (SM-S) technology is supported on all Hybrid and AFA platforms that have at least 16 GB of memory. SnapMirror Synchronous technology is a per-node, licensed feature that provides synchronous data replication at the volume level.
  • SnapVault archiving basics
    SnapVault is archiving technology, designed for disk-to-disk Snapshot copy replication for standards compliance and other governance-related purposes. In contrast to a SnapMirror relationship, in which the destination usually contains only the Snapshot copies currently in the source volume, a SnapVault destination typically retains point-in-time Snapshot copies created over a much longer period.
  • SnapMirror unified replication basics
    SnapMirror unified replication allows you to configure disaster recovery and archiving on the same destination volume. When unified replication is appropriate, it offers benefits in reducing the amount of secondary storage you need, limiting the number of baseline transfers, and decreasing network traffic.
  • XDP replaces DP as the SnapMirror default
    Starting with ONTAP 9.5, SnapMirror extended data protection (XDP) mode replaces SnapMirror data protection (DP) mode as the SnapMirror default.
  • When a destination volume grows automatically
    During a data protection mirror transfer, the destination volume grows automatically in size if the source volume has grown, provided there is available space in the aggregate that contains the volume.
  • Fan-out and cascade data protection deployments
    You can use a fan-out deployment to extend data protection to multiple secondary systems. You can use a cascade deployment to extend data protection to tertiary systems.
  • SnapMirror licensing
    With the introduction of ONTAP 9.5, licensing has been simplified for replicating between ONTAP instances. In ONTAP 9.x releases, the SnapMirror license supports both vault and mirror relationships. Users can now purchase a SnapMirror license to support ONTAP replication for both backup and disaster recovery use cases.
  • DPO systems feature enhancements
    Starting with ONTAP 9.6, the maximum number of FlexVol volumes supported increases when the DP_Optimized (DPO) license is installed. Starting with ONTAP 9.5, systems with the DPO license support SnapMirror backoff, cross-volume background deduplication, cross-volume inline deduplication, use of Snapshot blocks as donors, and compaction.
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