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Managing SnapMirror volume replication

SnapMirror offers three types of data protection relationship: SnapMirror DR, SnapVault, and unified replication. You can follow the same basic workflow to configure each type of relationship.

Beginning with general availability in ONTAP 9.9.1, SnapMirror Business Continuity (SM-BC) provides Zero Recovery Time Objective (Zero RTO) or Transparent Application Failover (TAF) to enable automatic failover of business-critical applications in SAN environments. SM-BC is supported in a configuration of either two All Flash Array (AFA) clusters.

  • SnapMirror replication workflow
    For each type of SnapMirror data protection relationship, the workflow is the same: create a destination volume, create a job schedule, specify a policy, create and initialize the relationship.
  • Configuring a replication relationship in one step
    Starting in ONTAP 9.5, you can use the snapmirror protect command to configure a data protection relationship in a single step. You specify a list of volumes to be replicated, an SVM on the destination cluster, a job schedule, and a SnapMirror policy. snapmirror protect does the rest.
  • Configuring a replication relationship one step at a time
    For each type of data protection relationship, you need to create a destination volume, configure a job schedule, specify a policy, and create and initialize the relationship. You can use a default or custom policy.
  • Converting an existing DP-type relationship to XDP
    You can easily convert an existing DP-type relationship to XDP to take advantage of version-flexible SnapMirror.
  • Converting the type of a SnapMirror relationship
    Starting with ONTAP 9.5, SnapMirror Synchronous is supported. You can convert an asynchronous SnapMirror relationship to a SnapMirror Synchronous relationship or vice versa without performing a baseline transfer.
  • Converting the mode of a SnapMirror Synchronous relationship
    Starting with ONTAP 9.5, SnapMirror Synchronous relationships are supported. You can convert the mode of a SnapMirror Synchronous relationship from StrictSync to Sync or vice versa.
  • Serving data from a SnapMirror DR destination volume
    When disaster disables the primary site for a SnapMirror DR relationship, you can serve data from the destination volume with minimal disruption. You can reactivate the source volume when service is restored at the primary site.
  • Restoring files from a SnapMirror destination volume
    You can use a Snapshot copy in a SnapMirror destination volume to recover individual files, LUNs, NVMe namespaces, or to restore the entire contents of a volume. You can restore files to the original source volume or to a different volume.
  • Updating a replication relationship manually
    You might need to update a replication relationship manually if an update fails because the source volume has been moved.
  • Resynchronizing a replication relationship
    You need to resynchronize a replication relationship after you make a destination volume writeable, after an update fails because a common Snapshot copy does not exist on the source and destination volumes, or if you want to change the replication policy for the relationship.
  • Deleting a volume replication relationship
    You can use the snapmirror delete and snapmirror release commands to delete a volume replication relationship. You can then delete unneeded destination volumes manually.
  • Managing storage efficiency
    SnapMirror preserves storage efficiency on the source and destination volumes, with one exception, when postprocess data compression is enabled on the destination. In that case, all storage efficiency is lost on the destination. To correct this issue, you need to disable postprocess compression on the destination, update the relationship manually, and re-enable storage efficiency.
  • Using SnapMirror global throttling
    Starting with ONTAP 9.5, global network throttling is available for all SnapMirror and SnapVault transfers at a per-node level.
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