HP StorageWorks XP Remote Web Console Software - Manual (Page 86)

You can store one snapshot data at a time by using the pairsplit command, but you cannot
specify the snapshot data ID. For details about the pairsplit command, see the HP StorageWorks
XP RAID Manager User Guide.
XP Snapshot does not support Quick Split mode. If you specify Quick Split mode, snapshot data
will not be stored in the pool, even if the command ends normally. Therefore, even if you specify
Quick Split mode, Quick Split mode does not take effect.
Storing XP Snapshot Data by Consistency Group with At-Time Snapshot
Function
With RAID Manager, you can store snapshot data by a consistency group (At-Time Snapshot
function).
Consistency groups have the following restrictions:
Table 31 Specifications of Consistency Group
Descriptions Items
A number is assigned to each consistency group within a
range of 0 to 255. You can specify a consistency group
number when you create XP Snapshot pairs. If you do not
specify a number, an unused number is assigned
automatically. Use the Volume List of the XP Snapshot
window or Pair Operation window of XP Business Copy
Software to view the list of the consistency group numbers.
You can configure up to 256 consistency groups in a
storage system, including XP Business Copy consistency
groups and Hitachi ShadowImage for Mainframe
consistency groups.
Consistency group number
You can define up to 8,192 XP Snapshot pairs in a
consistency group.
XP Business Copy Software pairs, Hitachi ShadowImage™
for Mainframe, and XP Snapshot pairs cannot coexist in
the same consistency group.
Number of pairs
A summary of the steps to store snapshot data using the At-Time Snapshot function of RAID Manager
is listed below. For details about the steps, see the HP StorageWorks XP RAID Manager User
Guide.
1. Execute the paircreate command with specifying the consistency group number.
The XP Snapshot pair that is the target of the At-Time Snapshot function is created.
The XP Snapshot function is enabled automatically by specifying the consistency group number.
2. Execute the paircreate command again by specifying the same consistency group number
specified in step 1.
You can add pairs into the same consistency group. Repeat this step for each number of pairs
that you want to specify into the same consistency group.
3. Execute the pairsplit command to the consistency group that is a target of the At-Time
Snapshot function.
After the XP24000/XP20000 Disk Array accepts the pairsplit command, the snapshot
data of the P-VOL will be stored at the time when the host issues an I/O request to each P-VOL
in the corresponding consistency group.
86 Performing XP Snapshot Operations