Dell PowerVault ME4 Series Storage System Administrator’s Guide

Replication process

After you create a peer connection and replication set, you can then replicate volumes between the systems. The initial replication differs slightly from all subsequent replications in that it copies all of the allocated pages of the primary volume to the secondary volume. Depending on how large your source volume is and the speed of the network connection, this initial replication may take some time.

Subsequent replications are completed by resetting one of the hidden snapshots to contain the contents last replicated and then resetting the other hidden snapshot to the current primary volume contents and comparing the changes. The system writes any changes it finds on the hidden primary snapshot to the hidden secondary snapshot, after which the secondary volume is updated to contain the contents of the secondary volume.

The progress and status of the initial and subsequent replications are tracked and displayed. The timestamps for replication reflect the time zones of the respective systems. When viewed on a secondary system in a different time zone, for example, replication information will reflect the time zone of the secondary system. For more information on replicating, see Stopping a replication, Initiating or scheduling a replication from the Replications topic, Initiating or scheduling a replication from the Volumes topic, Resuming a replication, and Suspending a replication.

You can initiate a replication manually or by using a schedule. When creating a schedule for a replication set, you cannot specify for replication to occur more frequently than once an hour. For more information on scheduling a replication set, see Initiating or scheduling a replication from the Replications topic and Initiating or scheduling a replication from the Volumes topic.