HP XP P9500 Storage - Manual (Page 31)

technologies, depending on your installation requirements and standards. Neither Cnt Ac-J Z nor
Remote Web Console provides ERC between the primary and secondary sites.
When Cnt Ac-J Z is used as a data migration tool, ERC is recommended but not required. When
it is used as a disaster recovery tool, ERC is required to ensure effective disaster recovery operations.
When a pair is suspended due to an error condition, the primary system generates sense information
which results in an IEA491E system console message. This information should be transferred to
the primary site via the ERC for effective disaster detection and recovery.
Sharing volumes with other P9500 software volumes
Continuous Access Journal Z volumes can be shared with other product volumes. Sharing pair
volumes enhances replication solutions, for example, when Continuous Access Journal Z and
Continuous Access Synchronous Z or Business Copy Z volumes are shared.
For planning information, see the following:
•
“Sharing volumes ” (page 140)
•
“Configurations with Continuous Access Synchronous Z” (page 145)
•
“Configurations with Business Copy Z” (page 156)
Planning Cnt Ac-J Z in multiple P9500s using a consistency group
Copy operations can be run simultaneously on multiple Cnt Ac-J Z pairs residing in multiple primary
and multiple secondary systems. Data update order in copy processing is guaranteed to the
secondary systems when an extended consistency group (EXCTG) is used.
This is done by placing the journals in the secondary systems in one extended consistency group
(EXCTG). Cnt Ac-J Z uses the secondary EXCTG to maintain data update sequence of master
journals that are paired with restore journals in the secondary EXCTG. If no secondary EXCTG is
configured, data update sequence is not maintained, and data consistency is not maintained
between the primary storage systems and the secondary storage systems.
With multiple systems, you can also place the journals from both OPEN and mainframe systems
in the same RAID Manager consistency group. When this configuration is used, Cnt Ac-J Z journals
cannot be placed in an EXCTG.
In addition, Continuous Access Journal Z volumes in multiple systems can be shared with Continuous
Access Synchronous Z pairs. See
“Configurations with Continuous Access Synchronous Z” (page 145)
for more information:
You can register up to four journals in a single EXCTG. You combine master journals in an EXCTG
on the primary site for disaster recovery purposes (in order to restore operations after operating
at the secondary site).
Any combination of primary and secondary system journals can be used. For example, you can
include journals from four primary systems and four secondary systems, two primary systems and
one secondary system, and so on.
An example configuration is shown in the following figure.
Sharing volumes with other P9500 software volumes 31