Software Manual

The specifications for consistency group numbers are different from the specifications for journal
group numbers. One storage system has a total of 256 (0 to 255) consistency groups for the
primary and secondary data volumes (numbers 0 to 255) are assigned).
Note: The consistency group number of the primary and secondary data volumes to be paired
must be same.
Note: When XP Continuous Access Journal and Hitachi Universal Replicator™ for Mainframe
coexist in the same storage system, the consistency group number must be different from the XP
Continuous Access Asynchronous consistency group number.
Figure 4 (page 16) shows the corresponding consistency group number and journal group number.
Figure 4 Corresponding Consistency Group Number and Journal Group Number
Remote Copy Connections
The remote copy connections are the physical paths used by the primary storage systems to
communicate with the secondary storage systems. These physical paths are Fibre Channel interface
cables and must connect the primary to the secondary storage system and the reverse. Up to eight
paths can be established in both directions.
When Fibre Channel interface (optical multimode short-wave) connections are used, two switches
are required for distances greater than 0.5 km (1,640 feet), and distances up to 1.5 km (4,920
feet, 0.93 miles) are supported. If the distance between the primary and secondary sites is greater
than 1.5 km, the optical single-mode long-wave interface connections are required. When Fibre
Channel interface (single-mode long-wave) connections are used, two switches are required for
distances greater than 10 km (6.2 miles), and distances up to 30 km (18.6 miles) are supported.
See “Setting up Remote Copy Connections” (page 52) for further information on installing and
configuring the FC remote copy connections.
16 About XP Continuous Access Journal Operations