HP XP P9000 Command View Advanced Edition Software - Manual (Page 159)

• Creating pairs and pair groups , page 156
About volume capacity checking
A volume capacity check is conducted when the Pair Configuration Wizard is used to create or edit
mainframe copy pairs. This is done to help the administrator avoid difficulties with Reverse-Resync
operations involving primary and secondary volumes of mismatched sizes. (Although it is possible to
create such copy pairs, an I/O error occurs if you execute a Reverse-Resync operation under this
condition. Because there is no recovery method available to make a Reverse-Resync operation
executable, storage volumes must be recreated from scratch.)
Volume capacity is expressed in the number of cylinders. This information is acquired from HP
StorageWorks P9000 for Business Continuity Manager Software when the volume is scanned and
when the configuration is refreshed.
If the Pair Configuration Wizard detects a discrepancy between the capacity of the selected primary
and secondary volumes, a warning message is displayed prompting the administrator to check the
configuration. (A similar message is displayed if no information about the volume capacity can be
acquired.)
NOTE:
The number of cylinders cannot be obtained when using HP StorageWorks P9000 for Business
Continuity Manager Software versions prior to 6.7.0.
Defining copy groups
This module discusses information about copy groups and tasks for defining copy groups:
• About copy groups , page 159
• About assigning CTGID/JNLGID for copy pairs , page 160
• Configuring open and mainframe consistency groups , page 161
• About HORCM instances , page 161
• Creating copy groups , page 162
• Changing copy group names , page 163
• Associating pair groups with copy groups , page 164
About copy groups
A copy group consists of a number of copy pairs that have been grouped for management purposes.
By grouping the copy pairs of volumes that are used for the same operations and purposes, you can
perform batch operations on all the copy pairs in that copy group. For example, by performing an
operation such as changing the copy pair status on a copy group, you can change the copy pair
status of all copy pairs in the copy group in a single operation.
Mainframe copy pairs can be grouped into two types of copy groups for maintaining data consistency
during replication. Copy groups can be defined without a container, in which case data consistency
is maintained per copy group. Copy groups can also be defined with a container, where each
container consists of multiple copy groups. In the latter case, data consistency is maintained per
container. There are limitations on the permitted combinations of copy group and container. For
details on these limitations, see “
Supported copy group and container combinations ” on page 165.
Related topics
User Guide 159