How cascade deployments work

SnapMirror supports mirror-mirror, mirror-vault, vault-mirror, and vault-vault cascade deployments.

A mirror-mirror cascade deployment consists of a chain of relationships in which a source volume is mirrored to a secondary volume, and the secondary volume is mirrored to a tertiary volume. If the secondary volume becomes unavailable, you can synchronize the relationship between the primary and tertiary volumes without performing a new baseline transfer.

Starting with ONTAP 9.6, SnapMirror Synchronous relationships are supported in a mirror-mirror cascade deployment. Only the primary and secondary volumes can be in a SnapMirror Synchronous relationship. The relationship between the secondary volumes and tertiary volumes must be asynchronous.


SnapMirror deployment: Source to mirror-mirror cascade chain

A mirror-vault cascade deployment consists of a chain of relationships in which a source volume is mirrored to a secondary volume, and the secondary volume is vaulted to a tertiary volume.


SnapMirror deployment: Source to mirror-vault cascade chain

Vault-mirror and, starting with ONTAP 9.2, vault-vault cascade deployments are also supported: