Managing Serviceguard 14th Edition, June 2007

Troubleshooting Your Cluster
Replacing Disks
Chapter 8 395
NOTE If you restore or recreate the volume group for the lock disk and you need
to re-create the cluster lock (for example if no vgcfgbackup is available),
you can run cmdisklock to re-create the lock. See the cmdisklock (1m)
manpage for more information.
Replacing a Lock LUN
You can replace an unusable lock LUN while the cluster is running,
provided you do not change the devicefile name (DSF).
IMPORTANT If you need to replace a LUN under the HP-UX 11i v3 agile addressing
scheme (see “About Device File Names (Device Special Files)” on
page 111), you may need to use the io_redirect_dsf(1M) command to
reassign the existing DSF to the new device, depending on whether the
operation changes the WWID of the LUN; see the section on
io_redirect_dsf in the white paper The Next Generation Mass Storage
Stack under Network and Systems Management -> Storage Area
Management on docs.hp.com.
If, for any reason, you are not able to use the existing DSF for the new
device, you must halt the cluster and change the name of the DSF in the
cluster configuration file; see “Updating the Cluster Lock Disk
Configuration Offline” on page 349.
CAUTION Before you start, make sure that all nodes have logged a message such as
the following in syslog:
WARNING: Cluster lock LUN /dev/dsk/c0t1d1 is corrupt: bad
label. Until this situation is corrected, a single failure
could cause all nodes in the cluster to crash.
Once all nodes have logged this message, use a command such as the
following to specify the new cluster lock LUN:
cmdisklock reset /dev/dsk/c0t1d1