Creating snapshot xp pairs, Storing snapshot data, Restoring snapshot xp pairs – HP StorageWorks XP Remote Web Console Software User Manual

Page 18

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18

Snapshot XP functions

2.

Create a Snapshot XP pair.

3.

Store the snapshot data in the pool.

4.

Execute the command again to recognize the device.

NOTE:

Servers (including RAID Manager XP) show V-VOLs with emulation type 0 (for example, OPEN-0V).

When creating a Snapshot XP pair, specify the volume with emulation type 0, such as OPEN-0V, as the

S-VOL.

Before creating a V-VOL, you must define a V-VOL group. The emulation type of the V-VOLs and the

emulation type of the VDEV for a V-VOL group are OPEN-V. In addition, the VDEV’s capacity 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 pane in Command View XP or XP Remote Web Console. For more

information, see ”

Creating or deleting virtual volumes

” on page 49.

Creating Snapshot XP pairs

A Snapshot XP pair uses a V-VOL as its S-VOL. Therefore, you must create a V-VOL before creating a

Snapshot XP pair. In Snapshot XP, you can specify up to 64 S-VOLs for a P-VOL.
To create Snapshot XP pairs, use a RAID Manager XP command. For more information, see ”

Creating

Snapshot XP pairs

” on page 55.

CAUTION:

When creating Snapshot XP pairs, you decide which pool the pairs use. If you create two or

more Snapshot XP pairs that share the same P-VOL, you must specify the same pool for these pairs. For

example, if you specify three S-VOLs for one P-VOL, you must specify the same pool for these three pairs.

NOTE:

When deleting a Snapshot XP pair, the volumes’ status becomes SMPL(PD). You cannot create

pairs 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 volumes’ status changes to SMPL.

Use the Business Copy XP main pane to see the volume’s status. Using RAID Manager XP, you can check

the volume status with the

pairdisplay

command, but you cannot distinguish between SMPL and

SMPL(PD) volumes. To distinguish between SMPL and SMPL(PD) volumes using RAID Manager XP, issue

the

inqraid

command as well. The

inqraid

command shows whether Snapshot XP is using the

volume. If Snapshot XP is not using the volume, the volume status is SMPL. If Snapshot XP is using the

volume, the volume status is SMPL(PD).

Storing snapshot data

Snapshot data is a replica of data in a Snapshot XP pair’s P-VOL, and is stored in a pool. When the

P-VOL is updated, updated data is copied to the pool as snapshot data before the P-VOL is updated. This

process is called storing snapshot data.
If you issue a command to a Snapshot XP pair to store snapshot data, the snapshot data is stored in the

pool when a host issues a write request to the Snapshot XP pair’s P-VOL.
To store snapshot data in a pool, use a RAID Manager XP command. For more information, see

Storing

snapshot data

” on page 55.

Restoring Snapshot XP pairs

Snapshot XP can restore a P-VOL’s contents to the state when the snapshot data was stored in the pool by

writing the snapshot data back to the P-VOL. Writing the snapshot data to the P-VOL is called restoration

of a Snapshot XP pair.

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