Specifying storage for version 20 DCO plexes

If you move the disks that contain volumes and their snapshots into different disk groups, you must ensure that the disks that contain their DCO plexes can accompany them. You can use storage attributes to specify which disks to use for the DCO plexes. (If you do not want to use dirty region logging (DRL) with a volume, you can specify the same disks as those on which the volume is configured, assuming that space is available on the disks). For example, to add a DCO object and mirrored DCO volume with plexes on disk05 and disk06 to the volume, myvol, use the following command:

# vxsnap -g mydg prepare myvol ndcomirs=2 alloc=disk05,disk06

To view the details of the DCO object and DCO volume that are associated with a volume, use the vxprint command. The following is example vxprint -vh output for the volume named vol1 (the TUTIL0 and PUTIL0 columns are omitted for clarity):

TY    NAME         ASSOC       KSTATE   LENGTH  PLOFFS  STATE      ...
v     vol1         fsgen       ENABLED  1024    -       ACTIVE
pl    vol1-01      vol1        ENABLED  1024    -       ACTIVE
sd    disk01-01    vol1-01     ENABLED  1024    0       -
pl    foo-02       vol1        ENABLED  1024    -       ACTIVE
sd    disk02-01    vol1-02     ENABLED  1024    0       -
dc    vol1_dco     vol1        -        -       -       -
v     vol1_dcl     gen         ENABLED  132     -       ACTIVE
pl    vol1_dcl-01  vol1_dcl    ENABLED  132     -       ACTIVE
sd    disk03-01    vol1_dcl-01 ENABLED  132     0       -
pl    vol1_dcl-02  vol1_dcl    ENABLED  132     -       ACTIVE
sd    disk04-01    vol1_dcl-02 ENABLED  132     0       -

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.


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 the vxassist(1M) manual page.

See the vxsnap(1M) manual page.

More Information

Moving DCO volumes between disk groups