HP XP P9000 for Business Continuity Manager Software User Guide (T5253-96081, July 2013)

Figure 25 A 4x4x4 Cascade configuration example
Operations during a host failure at the primary site
During a host failure at the primary site, the Reverse Resync function is used to reverse the copying
direction of the Continuous Access Synchronous Z copy group from the intermediate site to the
primary site. As a result, the configuration can be switched to a Multi-Target configuration whose
operations are performed from the intermediate site to continue the operations.
Figure 26 (page 64) shows a configuration example after a failover during a host failure at the
primary site.
Replication products and data center configurations 63