HP XP Racks - Manual (Page 24)

In this case, because the value of Maximum Initial Copy Activities is 2, initial copy operations for
LUN 02 and LUN 00 are started. If either one of the initial copy operations for LUN 02 and LUN
00 is completed, the initial copy for LUN 01 is started.
Example 2: initial copy started, new pairs added
The following table shows the Priority value when the initial copy is already begun and then two
new pairs are added. The P-VOLs are for the new pairs
Value set for Priority P-VOL
2 LUN 10
1 LUN 11
If initial copy is already started, and if a new initial copy is added, the additional initial copy is
started after the previously performed initial copy is completed. The priority of all the initial copy
operations being performed is shown in the following table.
Remarks Value set for Priority P-VOL Starting order for initial
copy
Previously scheduled. 1 LUN 02 1
Previously scheduled. 2 LUN 00 2
Previously scheduled. 3 LUN 01 3
Previously scheduled. 4 LUN 03 4
Scheduled later. 1 LUN 11 5
Scheduled later. 2 LUN 10 6
Priority is determined within the range of the number of initial copy operations performed at the
same time. Therefore, until the first initial copy operations complying with the order set by Priority
are completed, the additional initial copy operations are not started.
Consistency group planning
Consistency groups allow you to perform one operation on all pairs in the group. Consistency
groups also ensure that all pairs are managed in a consistent status.
You determine which pairs to include in a particular consistency group. This is based on business
criteria for keeping status consistent across a group of pairs, and for performing specific operations
at the same time on the group.
•
A consistency group can consist of the pairs in one primary and one secondary XP7, or pairs
in multiple primary and secondary XP7s.
•
Both Cnt Ac-S and Cnt Ac-S Z pairs can belong to the same consistency group.
Consistency group for pairs in one primary and one secondary XP7
Cnt Ac-S and Cnt Ac-S Z pairs between one primary and secondary system can be placed in the
same consistency group, as shown in the following figure.
24 Planning for Continuous Access Synchronous