Technical information

June 2012 Dell EqualLogic Configuration Guide v13.2 29
3.8.2 Replication Paths
The example replication paths shown in Figure 11 are described below.
• Basic partnership: one partner group hosts the primary copy of the volume and a second
partner group hosts the replica copy of the same volume. We also show the reverse direction
of the path for the Fast Failback replication feature, if it is enabled for the replica set.
• Single to multiple group partnership: a single group can support replication of multiple
primary volumes to different secondary replication partner groups.
• Reciprocal partnership: you can create bi-directional replication paths between partner
groups
• Multiple to single group partnership: a common scenario in which multiple primary groups
replicate their volumes to a single secondary group partner in a different location.
Figure 11 Replication Partnership Paths
3.8.3 Replication Process
When a replica is created the first replication process completes transfer of all volume data. For
subsequent replicas, only the data that changed between the start time of the previous replication
cycle and the start time of the new replication cycle is transferred to the secondary group. Dedicated
volume snapshots are created and deleted in the background as necessary to facilitate the replication
process. A volume replication set can be described as a combination of the following:
A volume replica set is defined as follows: