Overview of 3DC multi-target configuration using delta resync

In the 3DC multi-target configuration using delta resync, the data center is placed at the primary site and the two secondary sites. At least one storage system (VSP G800, VSP F800, VSP G1000, or HUS VM) is required at the primary site, intermediate site, and secondary site.

In this configuration, you can bring the S-VOL to a consistent state more quickly after failure because only the missing differential data must be copied. If you create the UR delta resync pairs beforehand, you can synchronize UR S-VOLs by using the UR journal data at the TC secondary site. The TC S-VOL and UR S-VOL are used for creating UR delta resync pairs. The following illustration shows this configuration. For details about setting up the 3DC multi-target configuration using delta resync, see 3DC multi-target configuration using delta resync.