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6 Using Dell PS Series Asynchronous Replication | TR1052
1 About Asynchronous Replication
A replica represents the contents of a volume at the time the replica was created. Each replicated volume
has a replica set, which is the set of replicas created over time.
A volume and its replicas are always stored on different groups connected by a robust network link.
Separating the groups geographically protects volume data in the event of a complete site disaster.
To replicate volume data, configure the group that contains the volume and the group that will store the
replicas as replication partners. A group can have multiple partners, but a volume can replicate to only one
partner.
Primary group. This is the group storing the volume. The primary group administrator configures
the secondary group as a replication partner and initiates the replication operation. Replication
from the primary group is considered outbound.
Secondary group. This is the group storing the replicas. The secondary group administrator
configures the primary group as a replication partner and provides space for the replicas.
Replication to the secondary group is considered inbound. Refer to the section, Primary and
secondary group administration, for more information.
Mutual authentication using passwords provides security between partners.
Each partner plays a role in the replication of a volume, and you can monitor replication activity from
either partner. A PS Series group can have up to 16 replication partners
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. This gives you significant flexibility
to choose a replication configuration that meets your needs, such as:
One group replicates to another group.
One group replicates different volumes to different groups.
Two groups replicate to each other.
Several groups replicate to the same secondary group.
Note: For additional information on replication, refer to the Dell PS Series
Group Manager
Administrator’s Manual
on eqlsupport.dell.com (login required).
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The limits mentioned in this document apply to PS Series groups that contain at least one member that is not a PS4000. In a
group of only PS4000 arrays, the limits are two members per group, two replication partners, and 32 volumes configured for
replication. See the latest PS Series release notes on eqlsupport.dell.com for the complete supported configuration limits.