SnapMirror offers two types of data protection relationship. For each type, SnapMirror creates a Snapshot copy of the Element source volume before initializing or updating the relationship:

The first time you invoke SnapMirror, it performs a baseline transfer from the source volume to the destination volume. The SnapMirror policy defines the contents of the baseline and any updates.

You can use a default or custom policy when you create a data protection relationship. The policy type determines which Snapshot copies to include and how many copies to retain.

The table below shows the default policies. Use the MirrorLatest policy to create a traditional DR relationship. Use the MirrorAndVault or Unified7year policy to create a unified replication relationship, in which DR and long-term retention are configured on the same destination volume.

Every policy with the “mirror-vault” policy type must have a rule that specifies which Snapshot copies to replicate. The rule “daily”, for example, indicates that only Snapshot copies assigned the SnapMirror label “daily” should be replicated. You assign the SnapMirror label when you configure Element Snapshot copies.

You can use SnapMirror to replicate Snapshot copies of an Element volume to an ONTAP destination system. In the event of a disaster at the Element site, you can serve data to clients from the ONTAP system, then reactivate the Element source volume when service is restored.

An Element volume is roughly equivalent to an ONTAP LUN. SnapMirror creates a LUN with the name of the Element volume when a data protection relationship between Element software and ONTAP is initialized. SnapMirror replicates data to an existing LUN if the LUN meets the requirements for Element to ONTAP replication.

Replication rules are as follows:

You can replicate Snapshot copies of a LUN created on an ONTAP system back to an Element volume:

Replication rules are as follows:

You must have completed the following tasks before configuring a data protection relationship between Element and ONTAP:

The following table shows support details for Element to ONTAP backup.