Creation of a virtual volume, Creation of an xp snapshot pair – HP StorageWorks XP Remote Web Console Software User Manual
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Warning:
The capacity of a pool is equal to the total capacity of the pool-VOLs registered in the pool.
The status of the XP Snapshot pair will be PSUE (status when failure occurred) when the usage rate of the
pool exceeds the capacity of the pool as a result of writing data in the volume of that pair. Snapshot
data cannot be stored in the pool, and no XP Snapshot pair can be created. Please read the notes in
Notes on Defining Pool Capacity
” on page 31 and ensure that there is sufficient pool capacity.
To create a pool, use the Pool window of the Remote Web Console. For details about the Pool window,
see “
” on page 44. For details about how to create a pool and how to add a pool-VOL,
see “
Creation of a Virtual Volume
A V-VOL is a virtual volume which does not have physical memory space. A V-VOL needs to be
created before you create an XP Snapshot pair because you must use a V-VOL as the S-VOL of an
XP Snapshot pair.
The definition of a V-VOL cannot be released if the V-VOL is being used as the S-VOL of an XP Snapshot
pair. To release the definition, you must delete the XP Snapshot pair that uses the V-VOL.
Caution:
If you are using HP-UX as a host server, mind the following when you execute the command on
V-VOLs in order to recognize the device from the host server:
•
If the device is already recognized by the host server, do not change its volumes to V-VOLs.
•
Before executing the command to recognize the device, create XP Snapshot pairs and store
snapshot data.
If you do not follow the cautions above, an error may occur and the host server may be terminated.
When the host server is terminated because of the command to recognize the device, retry the command
by following the steps below:
1.
Force the command process and its parent process to terminate.
2.
Create an XP Snapshot pair.
3.
Store the snapshot data in the pool.
4.
Execute the command again to recognize the device.
Notes:
•
Servers (including RAID Manager) will indicate the emulation type of the V-VOLs with a 0 (for
example, OPEN-0V). When you create an XP Snapshot pair, specify the volume whose emulation
type is displayed with 0, such as OPEN-0V, as the S-VOL.
•
Before creating a V-VOL, you need to define a V-VOL group. Like the emulation type of V-VOLs,
the emulation type of a VDEV for a V-VOL group is OPEN-V. In addition, the capacity of the VDEV
is always 2 TB. Therefore, the maximum capacity of a V-VOL is also 2 TB.
To delete a V-VOL, use the V-VOL window of the Remote Web Console. For details about the
V-VOL window, see “
” on page 48. For details about how to create a V-VOL, see
Creating or Deleting Virtual Volumes
Creation of an XP Snapshot Pair
An XP Snapshot pair uses a V-VOL as its S-VOL. Therefore, you need to create a V-VOL before creating an
XP Snapshot pair. In an XP Snapshot pair, up to 64 S-VOLs can be specified for a P-VOL.
To create an XP Snapshot pair, use a command of RAID Manager. For details about the operation to
create XP Snapshot pairs, see “
Caution:
When you create an XP Snapshot pair, you decide which pool to be used by the pair. If you
create two or more XP Snapshot pairs that share the same P-VOL, you need to specify the same pool for
these pairs. For example, if you specify three S-VOLs for one P-VOL, you need to specify the same pool
for these three pairs.
Note:
When you delete an XP Snapshot pair, the status of the volumes becomes SMPL(PD). You cannot
create pairs by using SMPL(PD) volumes. If the volumes are in SMPL(PD) status, wait for a while and issue
the command to create pairs after the volume status changes to SMPL.
XP24000 Snapshot User's Guide
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