Hitachi ShadowImage for z/OS user guide (HIT9503-96007, October 2007)

ShadowImage for z/OS user guide 31
At-Time Split Function
To use the At-Time Split function, you need Business Continuity Manager software. Business Continuity
Manager software is to be executed from a host server. To perform the split operation by using the At-Time
Split function, you must specify a copy group or register the split time in the copy group. The split time
indicates the time when you want to store the S-VOL data to the T-VOL.
For example, if you register the consistency group of ShadowImage for z/OS as the copy group of the
Business Continuity Manager, the At-Time Split function enables you to copy data from the SIz S-VOLs in
the same consistency group to T-VOLs simultaneously. The T-VOLs will contain the same data as the S-VOLs
when the Split operation is performed.
For instructions on using Business Continuity Manager, please refer to the Business Continuity Manager™
User and Reference Guide.
An SI390 consistency group is a user-defined set of SI390 volume pairs used for the At-Time Split function
and have the following restrictions:
• You can configure up to 128 consistency groups in a disk array, including the BC consistency groups.
• A number (0-127) is assigned to each consistency group. You can specify a consistency group number
when you create SI390 pairs.
• You can view the ID of the consistency groups used as the pair unit using Command View XP or XP
Remote Web Console or by executing the ATQUERY command.
• You can define up to 4,096 SI390 pairs in a consistency group.
• SI390 pairs and BC pairs cannot co-exist in the same consistency group.