VERITAS Volume Manager 4.1 Administrator's Guide

Administering Volumes

Backing up Volumes Online

Chapter 8 315

Here the nmirror attribute speciﬁes the number of mirrors in the

snapshot volume that are to be re-attached.

Once the snapshot plexes have been reattached and their data

resynchronized, they are ready to be used in another snapshot operation.

By default, the data in the original volume is used to update the

snapshot plexes that have been re-attached. To copy the data from the

replica volume instead, use the following command:

# vxassist -o resyncfromreplica snapback snapshot

CAUTION Unmount the ﬁle system corresponding to the primary volume before

using the resyncfromreplica option.

Dissociating a Snapshot Volume (snapclear)

The link between a snapshot and its original volume can be permanently

broken so that the snapshot volume becomes an independent volume.

If Non-Persistent FastResync is enabled on the original volume, use the

following command to dissociate the snapshot volume, snapshot:

# vxassist snapclear snapshot

If Persistent FastResync is enabled, and both the snapshot volume and

the original volume are still in the same disk group, use either of the

following commands to stop FastResync tracking on both volumes with

respect to each other:

# vxassist snapclear volume snap_object1

# vxassist snapclear snapshot snap_object2

Here snap_object1 is the snap object in the original volume that refers to

the snapshot volume, and snap_object2 is the snap object in the snapshot

volume that refers to the original volume. For example, if myvol and

SNAP-myvol are in the same disk group mydg, either of the following

commands stops tracking for both myvol and SNAP-myvol:

# vxassist -g mydg snapclear SNAP-myvol myvol_snp

# vxassist -g mydg snapclear myvol SNAP-myvol_snp