Veritas Volume Manager 5.1 SP1 Administrator"s Guide (5900-1506, April 2011)

In this output, the DCO object is shown as vol1_dco, and the DCO volume as
vol1_dcl with 2 plexes, vol1_dcl-01 and vol1_dcl-02.
If you need to relocate DCO plexes to different disks, you can use the vxassist
move command. For example, the following command moves the plexes of the
DCO volume, vol1_dcl, for volume vol1 from disk03 and disk04 to disk07 and
disk08.
Note: The ! character is a special character in some shells. The following example
shows how to escape it in a bash shell.
# vxassist -g mydg move vol1_dcl \!disk03 \!disk04 disk07 disk08
See “Moving DCO volumes between disk groups” on page 255.
See the vxassist(1M) manual page.
See the vxsnap(1M) manual page.
Using a DCO and DCO volume with a RAID-5 volume
You can add a DCO and DCO volume to a RAID-5 volume. This lets you use
Persistent FastResync on the volume for fast resynchronization of snapshots on
returning them to their original volume. However, this procedure has the side
effect of converting the RAID-5 volume into a special type of layered volume. You
can create space-optimized instant snapshots of such a volume, and you can add
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 364.
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 359.
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.
361Administering volumes
Preparing a volume for DRL and instant snapshots