Journal groups, Data volume pairs, Journal groups data volume pairs – HP XP Continuous Access Software User Manual
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in managing the XP Continuous Access Journal pair status and configuration (for example,
rejects write I/Os to XP Continuous Access Journal secondary data volumes). The secondary
array continuously issues read journal commands to the primary array in order to copy journals.
For XP Command View Advanced Edition Software, the secondary management station should
be connected to the secondary array at the secondary site on a separate LAN. The secondary
array should also be attached to a host system to:
◦
Report sense information if a problem with a secondary data volume or secondary array
occurs.
◦
Provide disaster recovery capabilities.
The local array can function simultaneously as a primary array for one or more primary data
volumes and as a secondary array for one or more secondary data volumes if the remote
copy connections and Fibre Channel interface ports are properly configured. You can use XP
Continuous Access Journal to specify the secondary array from the connected primary array.
You can perform XP Continuous Access Journal operations on all internal LDEVs except XP
Command View Advanced Edition Software or XP Remote Web Console command devices.
For more information about local array command devices, see the HP StorageWorks LUN
Configuration and Security Manager XP user guide for the XP12000/XP10000/SVS200.
NOTE:
When configuring a journal group pair, you must specify the serial numbers of the
primary and secondary arrays. You must specify different serial numbers for the primary array
and secondary array for a journal group pair. If you must specify the same serial number,
contact your HP account support representative.
Journal groups
A journal group consists of two or more data volumes and journal volumes. You can use a journal
group to tailor XP Continuous Access Journal for your unique business content. A journal volume
in the primary array is referred to as a master journal volume. A journal volume in the secondary
array is referred to as a restore journal volume. The data volume in the master journal group is
called the primary data volume. The data volume in the restore journal group is similarly called
the secondary data volume.
The data update sequence from the host is managed and ensured at the level of a matched set of
a master and restore journal group. The journal numbers of paired master and restore journal
groups can be different. A particular data volume or journal volume can belong to only one journal
group.
Data volume pairs
XP Continuous Access Journal performs remote copy operations for data volume pairs that you
have created. Each XP Continuous Access Journal pair consists of one primary data volume and
one secondary data volume, which are typically located in different arrays. XP Continuous Access
Journal primary data volumes are the primary volumes (LUs) containing the original data. XP
Continuous Access Journal secondary volumes are the secondary volumes (LUs) containing the
remotely duplicated data. During normal XP Continuous Access Journal operations, the primary
data volume remains available to hosts at all times for read and write I/O operations. During
normal XP Continuous Access Journal operations, the secondary array rejects all host-requested
write I/Os directed to the secondary data volume. The secondary data volume write enable option
allows write access to a secondary data volume while the pair is split and can use secondary and
primary data volume track maps to later resynchronize the pair (see
).
XP Continuous Access Journal data volume pairs also supports Volume Management and Cache
LUN XP, which allows XP Continuous Access Journal to meet a variety of user needs by way of
data copying and data migration. This ensures that all user data can be backed up or duplicated.
See
for more information about LUN requirements and support.
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Overview of XP Continuous Access Journal