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

103Administering disks
Rootability
size of the file systems on the target disk. (This takes advantage of the fact that most of
these file systems are usually nowhere near 100% full.) For example, to specify a size
reduction of 30%, the following command would be used:
# /etc/vx/bin/vxcp_lvmroot -R 30 -v -b c0t4d0
The verbose option, -v, is specified to give an indication of the progress of the operation.
Caution: Only create a VxVM root disk if you also intend to mirror it. There is no benefit
in having a non-mirrored VxVM root disk for its own sake.
The next example uses the same command and additionally specifies the
-m option to set
up a root mirror on disk c1t1d0:
# /etc/vx/bin/vxcp_lvmroot -m c1t1d0 -R 30 -v -b c0t4d0
In this example, the -b option to vxcp_lvmroot sets c0t4d0 as the primary boot device
and c1t1d0 as the alternate boot device.
This command is equivalent to using vxcp_lvmroot to create the VxVM-rootable disk,
and then using the
vxrootmir command to create the mirror:
# /etc/vx/bin/vxcp_lvmroot -R 30 -v -b c0t4d0
# /etc/vx/bin/vxrootmir -v -b c1t1d0
The disk name assigned to the VxVM root disk mirror also uses the format rootdisk##
with ## set to the next available number.
Note: The target disk for a mirror that is added using the vxrootmir command must be
large enough to accommodate the volumes from the VxVM root disk.
Once you have successfully rebooted the system from a VxVM root disk to
init level 1,
you can use the
vxdestroy_lvmroot command to completely remove the original LVM
root disk (and its associated LVM volume group), and re-use this disk as a mirror of the
VxVM root disk, as shown in this example:
# /etc/vx/bin/vxdestroy_lvmroot -v c0t0d0
# /etc/vx/bin/vxrootmir -v -b c0t0d0
Note: You may want to keep the LVM root disk in case you ever need a boot disk that
does not depend on VxVM being present on the system. However, this may require that
you update the contents of the LVM root disk in parallel with changes that you make to the
VxVM root disk. See “Creating an LVM root disk from a VxVM root disk” on page 103
for a description of how to create a bootable LVM root disk from the VxVM root disk.
For more information, see the
vxcp_lvmroot(1M), vxrootmir(1M),
vxdestroy_lvmroot(1M) and vxres_lvmroot (1M) manual pages.