VERITAS Storage Foundation 4.1 Intelligent Storage Provisioning Administrator's Guide

Chapter 5, Administering Instant Snapshots

Creating Instant Snapshots

The destroy and nmirror attributes are not supported for space-optimized instant

snapshots.

The following example demonstrates how to restore the volume, myvol, from the space-optimized

snapshot, snap3myvol.

# vxsnap -g mydg restore myvol source=snap3myvol

Dissociating an Instant Snapshot (vxsnap dis)

The following command breaks the association between a snapshot volume, snapvol, and its parent

volume, so that the snapshot may be used as an independent volume:

# vxsnap [-f] [-g diskgroup] dis snapvol

This operation fails if the snapshot, snapvol, has a snapshot hierarchy below it that contains

unsynchronized snapshots. If this happens, the dependent snapshots must be fully synchronized

from snapvol. When no dependent snapshots remain, snapvol may be dissociated. The snapshot

hierarchy is then adopted by snapvol’s parent volume.

Note To be usable after dissociation, the snapshot volume and any snapshots in the hierarchy must

have been fully synchronized. See “Controlling Instant Snapshot Synchronization” on

page 92 for more information. In addition, you cannot dissociate a snapshot if

synchronization of any of the dependent snapshots in the hierarchy is incomplete. If an

incomplete snapshot is dissociated, it is unusable and should be deleted as described in

“Removing an Instant Snapshot” on page 91.

The following command dissociates the snapshot, snap2myvol, from its parent volume:

# vxsnap -g mydg dis snap2myvol

Note When applied to a volume set or to a component volume of a volume set, this operation can

result in inconsistencies in the snapshot hierarchy in the case of a system crash or hardware

failure. If the operation is applied to a volume set, the -f (force) option must be specified.

Removing an Instant Snapshot

When you have dissociated a full-sized instant snapshot, you can use the vxvoladm command to

delete it altogether, as shown in this example:

# vxvoladm -g mydg remove volume snap2myvol

You can also use this command to remove a space-optimized instant snapshot from its cache. For

details of how to remove a cache, see “Removing a Cache” on page 81.