Restoring The P-Vol From The V-Vol - Hitachi AMS2100 User Manual

Restoring the P-VOL from the V-VOL

Hitachi AMS 2000 Family Copy-on-Write SnapShot User Guide
SnapShot allows you to restore your P-VOL to a previous point in
time from any SnapShot image (V-VOL). The amount of time it takes
to restore your data depends on the size of the P-VOL, the amount
of data that has changed, and your AMS model.
When you restore the P-VOL:
• There is a short period when data in the V-VOL is validated to
insure that the restoration will complete successfully.
- During the validation stage, the host cannot access the P-
VOL.
- Even when no differential data exists, restoration is not
completed immediately. It takes from 6 to 15-minutes for
the array to search for differentials. The time depends on
the copy pace you have defined.
• Once validation is complete:
- Copying from V-VOL to P-VOL is performed in the
background.
- Pair status is Reverse Synchronizing.
- The P-VOL is available for read/write from the host.
•
NOTE: Splitting a pair while status is Reverse Synchronizing
causes other V-VOLs paired with the P-VOL to be placed in
Failure status. Also, the P-VOL data being restored cannot be
used logically.
The restore command can be issued to 128 P-VOLs at the same time,
but actual copying is performed on a maximum of four per controller
for AMS2100/2300, and eight per controller for AMS2500 at one
time. When background copying can be executed, the copies are
completed in the order the command was issued.
To restore the P-VOL from the V-VOL
(For instructions using CLI, see
on page B-16.)
1. Shut down the host application.
2. Un-mount the P-VOL from the production server.
3. In the Storage Navigator 2 GUI, select the Local Replication
icon in the Replication tree view.
4. In the GUI, select the pair to be restored in the Pairs list.
Advanced users using the Navigator 2 CLI, please refer to
Restoring V-VOL to P-VOL using CLI on page
5. Click Restore Pair. View subsequent screen instructions by
clicking the Help button.
Using SnapShot
Restoring V-VOL to P-VOL using CLI
B-16.
6-7