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

mirrors that may be broken off as full-sized instant snapshots. You cannot relayout
or resize such a volume unless you convert it back to a pure RAID-5 volume.
To convert a volume back to a RAID-5 volume, remove any snapshot plexes from
the volume, and dissociate the DCO and DCO volume from the layered volume.
You can then perform relayout and resize operations on the resulting non-layered
RAID-5 volume.
See “Removing support for DRL and instant snapshots from a volume” on page 323.
To allow Persistent FastResync to be used with the RAID-5 volume again,
re-associate the DCO and DCO volume.
See “Preparing a volume for DRL and instant snapshots” on page 318.
Warning: Dissociating a DCO and DCO volume disables FastResync on the volume.
A full resynchronization of any remaining snapshots is required when they are
snapped back.
Determining the DCO version number
To use the instant snapshot and DRL-enabled DCO features, you must use a version
20 DCO, rather than version 0 DCO.
To find out the version number of a DCO that is associated with a volume
1
Use the vxprint command on the volume to discover the name of its DCO.
Enter the following:
# DCONAME=`vxprint [-g diskgroup] -F%dco_name volume`
2
Use the vxprint command on the DCO to determine its version number. Enter
the following:
# vxprint [-g diskgroup] -F%version $DCONAME
321Administering volumes
Preparing a volume for DRL and instant snapshots