HP XP Racks - Manual (Page 25)

Grouping to simplify volume operations
Business Continuity Manager can group together copy pairs to improve the operability of managing
replicas of large-scale systems that handle substantial amounts of data. Copy pairs can be grouped
together and managed as a single entity.
Working with copy pairs in groups simplifies volume operation and reduces system administration
costs.
Figure 3 (page 25) shows an overview of volume operation.
Figure 3 Overview of volume operation
Copy groups
A copy group is a set of copy pairs that have the same copy type (Business Copy Z, Continuous
Access Synchronous Z, TrueCopy Asynchronous for Mainframe or Continuous Access Journal Z),
and is designated by a copy group ID for identification. An operation performed on a copy group
is performed on all of the copy pairs within that copy group.
To define a copy group and assign a copy group ID, see “Defining a copy group” (page 641) .
Consistency groups
A consistency group is a copy group recognized by a storage system.
A consistency group updates the S-VOLs in the same order that data was put onto the P-VOLs. The
data on an S-VOL is guaranteed to be identical to the data on a P-VOL at consistency times.
Therefore, data at the secondary site can be used to recover the data at the primary site. This is
called preserving consistency. The consistency of updates is assured throughout the entire consistency
group. For details on consistency time, see
“Consistency times and consistency delta values”
(page 32) .
Grouping to simplify volume operations 25