White Papers

49 PS Series Asynchronous Replication Best Practices and Sizing Guide | BP1012
Navigation tip: SAN Headquarters (primary) > Capacity > Outbound Replicas > Volumes (select volume)
Monitoring Replication with SAN Headquarters
7.7 Replicating large amounts of data
Some of the testing used 100 GB volumes for replication. Some tests replicated multiple 100 GB volumes
simultaneously, and others replicated only a single volume to show how this can affect overall replication
times.
A 100 GB volume is not a huge amount of data in today’s IT environments. By comparison, desktop and
portable systems typically now have 500 GB or larger hard disks and file servers may contain multiple
terabytes of user data. Replicating this amount of data can be extremely challenging over a slow link, and in
some cases, may not work at all. For example, if a 10 TB file share volume experiences a 1 percent daily
change rate, it would need to replicate approximately 100 GB per day. If the network is not fast enough to
support replication of 100 GB in under 24 hours, than it is unlikely that it will meet the RPO for most
businesses requirements.
All volumes will initially need to be fully synchronized. Depending on the initial space used in the volume and
the speed of the network between sites, the required time to accomplish this task can vary greatly. The
Manual Transfer Utility can be used to copy a volume to a portable disk drive and manually transfer the
volume to be replicated to the remote site. However, if it is determined that the initial synchronization of
replicas will take too long, this may just be the first sign that the network between replication partners is
under-sized and may not be able to support a regular replication schedule.