Managing Serviceguard Fifteenth Edition, reprinted May 2008

Building an HA Cluster Configuration
Preparing Your Systems
Chapter 5 209
Creating Mirrors of Root Logical Volumes
HP strongly recommends that you use mirrored root volumes on all
cluster nodes. The following procedure assumes that you are using
separate boot and root volumes; you create a mirror of the boot volume
(/dev/vg00/lvol1), primary swap (/dev/vg00/lvol2), and root volume
(/dev/vg00/lvol3). In this example and in the following commands,
/dev/dsk/c4t5d0 is the primary disk and /dev/dsk/c4t6d0 is the
mirror; be sure to use the correct device file names for the root disks on
your system.
NOTE Under agile addressing, the physical devices in these examples would
have names such as /dev/[r]disk/disk1
, and /dev/[r]disk/disk2.
See “About Device File Names (Device Special Files)” on page 112.
1. Create a bootable LVM disk to be used for the mirror.
pvcreate -B /dev/rdsk/c4t6d0
2. Add this disk to the current root volume group.
vgextend /dev/vg00 /dev/dsk/c4t6d0
3. Make the new disk a boot disk.
mkboot -l /dev/rdsk/c4t6d0
4. Mirror the boot, primary swap, and root logical volumes to the new
bootable disk. Ensure that all devices in vg00, such as /usr, /swap,
etc., are mirrored.
NOTE The boot, root, and swap logical volumes must be done in exactly the
following order to ensure that the boot volume occupies the first
contiguous set of extents on the new disk, followed by the swap and
the root.
The following is an example of mirroring the boot logical volume:
lvextend -m 1 /dev/vg00/lvol1 /dev/dsk/c4t6d0
The following is an example of mirroring the primary swap logical
volume: