9.5.01 HP P4000 SAN Solution User Guide (AX696-96168, February 2012)

between the original volume and the new SmartClone volume. For detailed information about
SmartClone volumes, see “What are SmartClone volumes?” (page 178).
• Use Remote Copy to copy the newer snapshots that you want to keep, before performing the
rollback. See the HP P4000 Remote Copy User Guide for more information about copying
data.
Best practices for rolling back a volume
• Stop any applications that are accessing the volume, and log off all related iSCSI sessions.
• If a volume is part of a volume set, typically you want to roll back each volume using its
corresponding snapshot. The system gives you the option to automatically roll back all
associated volumes. To see any associated snapshots, select a snapshot, click the Details tab,
and look at the Snapshot Set field. For more information, see “Creating snapshots for volume
sets” (page 165).
Restrictions on rolling back a volume
You cannot roll back a volume when a clone point exists that is newer than the snapshot you want
to use for rolling back. You can create a SmartClone from the snapshot you want to use, or you
must delete all but one volume that depends on that clone point. Once you delete all but one volume
that depends on a clone point, the clone point returns to being a standard snapshot.
Rolling back a volume to a snapshot or clone point
You can roll back a specific volume from a clone point. The clone point selected will roll back to
the parent volume it is listed under in the navigation view.
CAUTION: During a rollback, snapshots that are newer than the one you intend to roll back are
deleted. You will lose all data stored since the rolled-back snapshot was created. Consider creating
a SmartClone volume, or a Remote Copy, before the roll back to preserve that data.
1. Log in to the management group that contains the volume that you want to roll back.
2. In the navigation window, select the snapshot to which you want to roll back.
Review the snapshot Details tab to ensure you have selected the correct snapshot.
3. Click Snapshot Tasks on the Details tab, and select Roll Back Volume.
A warning message opens that illustrates the possible consequences of performing a rollback,
including
• Existing iSCSI sessions present a risk of data inconsistencies.
• All newer snapshots will be deleted.
• Changes to the original volume since the snapshot was created will be lost.
If you do not have connected iSCSI sessions or newer snapshots, those issues will not be
reflected in the message.
If the snapshot is part of a snapshot setIf the snapshot is not part of a snapshot set
You have the following possible choices for continuing
from this message window:
You have three choices for continuing from this
message window:
• Click Roll Back ALL Associated Volumes. This is
recommended. See “Roll back all associated volumes”
(page 176).
• Click OK. See “Continue with standard roll back”
(page 175).
• Click New SmartClone Volume. See “Create a new
SmartClone volume from the snapshot” (page 175). • Click Roll Back Selected Volume Only. See “Continue
with standard roll back” (page 175).
• Click Cancel. See “Cancel the rollback operation”
(page 176).
NOTE: This will only the roll back the volume of the
selected snapshot. Click OK. This is not recommended.
174 Using snapshots