Three-Site Data Center Data Protection using NetApp ONTAP 9.7 SnapMirror

In today’s constantly connected global business environment, companies expect rapid recovery of critical application data with zero data loss. Organizations devise effective disaster recovery plans by keeping the below requirements in mind:

• Data should be recoverable in the event of catastrophic failure at one or more data centers (disaster recovery).

• Data should be replicated and distributed in an optimal way, taking into consideration major business criteria such as cost of storage, protection level against site failures, and so on.

• What needs to be protected and for how long should be driven by:

Shrinking recovery point objective (RPO), to achieve zero data loss

     Near-zero recovery time objective (RTO), for faster recovery of business-critical applications in case of disaster

Three-Site Data Center Topology

The three-site data center configuration can be done in either fan-out or cascade topology.

Fan-out Topology

Fan-out topology consists of primary and near disaster recovery data centers within region sites (with replication network having <10ms round trip time), will synchronously replicate data between themselves to achieve zero RPO. And the primary asynchronously replicates data on a regular basis depending on the quantity of new data being generated to the remote or far disaster recovery out-of-region data center. If disaster strikes the primary site, the application can be started with zero data loss from the near disaster recovery data center, which would also take over asynchronous replication to the far disaster recovery data center.

Steps to Configure Fan-out Topology:

Create intercluster role Lif's and configure cluster peer and SVM peer.

Check the cluster peer and vserver peer in all the 3 site NetApp Clusters.

Cluster1  --- peered with cluster2 and cluster3

Cluster2 peered with cluster1 and cluster3.

Cluster3 is peered with cluster1 and cluster2.

In cluster1, create a new source volume (Ex- volnew). (Primary Site)

In cluster2, create a destination volume with DP type. (Near DR Site)

In cluster2, create SnapMirror  (SM-S) Sync relationship. 

Then initialize the Snapmirror relationship, once the base line transfer is successful, the status will be Insync.

In Cluster3, (Far DR Site) create a DP volume and create a Async SnapMirror relationship between Primary Site and Far DR site.

Initialize the SnapMirror Relationship.

Primary Site to Near  DR Site (Sync) 

Primary Site to Far DR Site (Async).

Cascade Topology

Cascade topology is where the primary would synchronously replicate to the near disaster recovery site, and the near disaster recovery site would asynchronously replicate data to the far disaster recovery site. In case the near disaster recovery site goes down, you can configure an asynchronous replication directly to the far disaster recovery site over longer distance to ensure all the delta updates are being updated or replicated.

In Cluster1(Primary Site), Create a source volume to replicate.

In Cluster2 (Near DR Site) , Create a DP volume.

In Cluster2, create a SnapMirror Sync relationship between these two volumes.

In Cluster3(Far DR Site), create a DP volume.

In cluster3, create a Snapmirror (Async) between cluster2 and Clster3 volumes.