Figure 72 Mirror Unit Descriptors

In a 3DC Sync/CAJ replication, the Continuous Access Synchronous replication must use MU# 0 and the Continuous Access Journal replication must use any of the remaining three MU# for remote replication. Figure 73 (page 422) shows an example of configuring MU numbers in 3DC Sync/CAJ environment when Delta Resync pair is configured between Site1 and Site3.

Figure 73 3DC Sync/CAJ solution and mirror unit descriptor usage example

In a 3DC CAJ/CAJ Tri-Link configuration using Delta Resync, only mirror unit descriptors “1”, “2” and “3” must be used for creating device groups. Figure 74 (page 423) shows an example of configuring MU numbers in 3DC CAJ/CAJ environment when Delta Resync pair is configured between Site2 and Site3.

422 Designing a Three Data Center Disaster Recovery Solution