Veritas Volume Manager 5.0.1 Administrator's Guide, HP-UX 11i v3, First Edition, November 2009

Adding plexes to a snapshot volume
If you want to retain the existing plexes in a snapshot volume after a snapback
operation, you can create additional snapshot plexes that are to be used for the
snapback.
To add plexes to a snapshot volume
1
Use the following vxprint commands to discover the names of the snapshot
volume’s data change object (DCO) and DCO volume:
# DCONAME=`vxprint [-g diskgroup] -F%dco_name snapshot`
# DCOVOL=`vxprint [-g diskgroup] -F%log_vol $DCONAME`
2
Use the vxassist mirror command to create mirrors of the existing snapshot
volume and its DCO volume:
# vxassist -g diskgroup mirror snapshot
# vxassist -g diskgroup mirror $DCOVOL
The new plex in the DCO volume is required for use with the new data plex
in the snapshot.
3
Use the vxprint command to find out the name of the additional snapshot
plex:
# vxprint -g diskgroup snapshot
4
Use the vxprint command to find out the record ID of the additional DCO
plex:
# vxprint -g diskgroup -F%rid $DCOVOL
5
Use the vxedit command to set the dco_plex_rid field of the new data plex
to the name of the new DCO plex:
# vxedit -g diskgroup set dco_plex_rid=dco_plex_rid new_plex
The new data plex is now ready to be used to perform a snapback operation.
Dissociating a snapshot volume
The link between a snapshot and its original volume can be permanently broken
so that the snapshot volume becomes an independent volume. Use the following
command to dissociate the snapshot volume, snapshot:
# vxassist snapclear snapshot
403Administering volume snapshots
Creating traditional third-mirror break-off snapshots