Replication Strategy

Several options for replication strategy are available. Each has advantages and disadvantages. You need to decide on the best strategy for your environment. For example, you might use different configuration options that are based on available space, application, how critical the data is, and legal requirements. Consider your environment, applications, availability needs, storage growth patterns, and recovery windows to create a replication strategy that best serves your needs.

Array relationships are based on the direction of replication. The source of the volume collection that is being replicated is the upstream replication partner. The destination is the downstream replication partner. A volume source that is upstream to one partner can be downstream to another. Downstream partners can become upstream partners by sending data to other replication partners and by replicating replicas.

NOTE: Synchronous replication only supports a one-to-one or reciprocal replication strategy.

One-to-One Replication

Basic replication involves replicating volumes from one array to another based on the protection schedules configured for their associated volume collections. A volume collection can have up to two replication partners, but only one partner can be associated with a schedule. Volume collections can have up to 10 protection schedules.

In this scenario, the second array could be used strictly for disaster recovery. Hourly and Daily represent volume collections that are configured with protection schedules that take snapshots at the specified frequency.


  1. Network
  2. Single volume assigned to the Hourly volume collection
  3. Multiple volumes assigned to the Daily volume collection
  4. Replica of volume in the Hourly volume collection
  5. Replicas of volumes in the Daily volume collection

One-to-Many Replication

You can set up a volume collection to have two replication partners. A volume collection can have up to ten protection schedules. Each schedule can have only one partner, but you can specify which partner is associated with which schedule. These schedules determine when the volumes are replicated and the array to which they are replicated.

Having two partners can improve the strength of your disaster recovery plan.

For example, you can have a scenario where the volumes are replicated to one partner array on an Hourly basis and to the other partner array on an Hourly and Daily basis. Or both arrays could use the same schedule.

Reciprocal Replication

Reciprocal replication involves replicating volumes that originate on two separate arrays to each other. Volumes on one array are replicated to a second array, and volumes on the second array are replicated to the first array. Each array acts as a disaster recovery option for the other. Reciprocal replication is sometimes called mutual replication.

In this example, SQL and Outlook represent volume collections that are configured with protection schedules and performance policies appropriate for those application types.


  1. Network
  2. Multiple volumes assigned to the SQL volume collection
  3. Replicas of volumes in the Outlook volume collection
  4. Replicas of volumes in the SQL volume collection
  5. Multiple volumes assigned to the Outlook volume collection

Many-to-One (Centralized) Replication

You can use one array as a centralized replica for volumes that originate on several other arrays.

In this example, Hourly, Daily, SQL, Outlook, and Datastore1 represent appropriately configured volume collections.


  1. Network
  2. Single volume assigned to the Daily volume collection
  3. Multiple volumes assigned to the SQL volume collection
  4. Multiple volumes assigned to the Hourly volume collection
  5. Replicas of volumes in the SQL volume collection
  6. Replicas of volumes in the Hourly volume collection
  7. Replicas of volumes in the Outlook volume collection
  8. Replicas of volumes in the Datastore1 volume collection
  9. Replica of volume in the Daily volume collection
  10. Multiple volumes assigned to the Outlook volume collection
  11. Multiple volumes assigned to the Datastore1 volume collection

Many-to-Many Replication

One way to do many-to-many replication involves replicating volumes on the same array to multiple replication partners using multiple volume collections. The individual volume collections can have up to two replication partners.

In this example, Hourly, Daily, SQL, Outlook, Datastore1, and Temporary represent appropriately configured volume collections.


  1. Network
  2. Multiple volumes that are assigned to the SQL volume collection
  3. Single volume that is assigned to the Daily volume collection
  4. Replicas of the volumes in the Hourly volume collection
  5. Replicas of the volumes in the Datastore1 volume collection
  6. Replicas of the volumes in the SQL volume collection
  7. Multiple volumes assigned to the Datastore1 volume collection
  8. Multiple volumes assigned to the Outlook volume collection
  9. Multiple volumes assigned to the Temporary volume collection
  10. Replicas of volumes in the Outlook volume collection
  11. Multiple volumes that are assigned to the Hourly volume collection
  12. Replica of volume in the Daily volume collection
  13. Replicas of the volumes in the Temporary volume collection