HP XP Racks - Manual (Page 39)

Journal Z is also used from the primary storage system for the remote storage system at the secondary
site.
NOTE: A Continuous Access Journal Z copy pair in the Delta Resync waiting status must be
created between the PPRC copy pair S-VOL and the Continuous Access Journal Z S-VOL beforehand.
4x4 configuration
This configuration performs remote copying from multiple storage systems on the primary site to
multiple storage systems on the secondary site with Continuous Access Journal Z to preserve
consistency.
Data center configurations 39