Veritas Volume Manager 5.0 Administrator's Guide (September 2006)

275Administering volumes
Resizing a volume
# vxprint [-g diskgroup] -ht volume
where volume is the name of the RAID-5 volume. For a RAID-5 log, the output lists a plex
with a STATE field entry of LOG.
To dissociate and remove a RAID-5 log and any associated subdisks from an existing
volume, use the following command:
# vxplex [-g diskgroup] -o rm dis plex
For example, to dissociate and remove the log plex volraid-02 from volraid in the
disk group, mydg, use the following command:
# vxplex -g mydg -o rm dis volraid-02
You can also remove a RAID-5 log with the vxassist command, as follows:
# vxassist [-g diskgroup] remove log volume [nlog=n]
By default, the vxassist command removes one log. Use the optional attribute nlog=n
to specify the number of logs that are to remain after the operation completes.
Note: When removing the log leaves the volume with less than two valid logs, a warning
is printed and the operation is not allowed to continue. The operation may be forced by
additionally specifying the -f option to vxplex or vxassist.
Resizing a volume
Resizing a volume changes the volume size. For example, you might need to increase the
length of a volume if it is no longer large enough for the amount of data to be stored on it.
To resize a volume, use one of the commands:
vxresize (preferred), vxassist, or
vxvol. Alternatively, you can use the graphical Veritas Enterprise Administrator (VEA)
to resize volumes.
If a volume is increased in size, the vxassist command automatically locates available
disk space. The
vxresize command requires that you specify the names of the disks to be
used to increase the size of a volume. The
vxvol command requires that you have
previously ensured that there is sufficient space available in the plexes of the volume to
increase its size. The
vxassist and vxresize commands automatically free unused
space for use by the disk group. For the
vxvol command, you must do this yourself. To
find out by how much you can grow a volume, use the following command:
# vxassist [-g diskgroup] maxgrow volume
When you resize a volume, you can specify the length of a new volume in sectors,
kilobytes, megabytes, or gigabytes. The unit of measure is added as a suffix to the length
(s, m, k, or g). If no unit is specified, sectors are assumed. The
vxassist command also
allows you to specify an increment by which to change the volume’s size.