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 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.
