update cluster lock information

[Ed D]

Hi,
I discovered that my cluster lock information is out of date since a SAN upgrade a couple of years ago. I was updating the scsi driver scsiU320 on the idle node of a 2 node cluster and on reboot the active node TOC'd. The following lines in cmclconfig.ascii are now out of date:
FIRST_CLUSTER_LOCK_VG
FIRST_CLUSTER_LOCK_PV (for each node)
Any advice on how best to update these? Is it just edit the file, copy to other node and cmapplyconf? Can I just pick any shared disk as the cluster lock disk? or does it have to be dedicated cluster lock disk with no user data on it? is downtime required?
Thanks

[Ed D]

additional info:
Service Guard A.11.16.00
HPUX 11.11 pa-risc

[Steven E. Protter]

Shalom,

edit the cluster configuration file.

Pick a cluster lock disk that is visible on both nodes

cmquerycl
cmcheckconf
cmapplyconf

SEP

[Ed D]

Thanks, Am I right in saying choosing a cluster lock disk which is shared and already in use won't affect any existing user data on that disk?

[Emil Velez · Accepted solution]

The cluster lock disk is a special structure inside the LVM bad block area and does not affect data inside the disk.

Any disk in a volume group that either system can see can be the lock disk. YOu must stop the cluster to change it at 11.16.

[P Arumugavel]

A lock disk or lock LUN can be used for clusters up to and including four nodes in size.

A cluster lock disk is a special area on an LVM disk located in a volume group that is shareable by all nodes in the cluster. Similarly, a cluster lock LUN is a small dedicated LUN, connected to all nodes in the cluster, that contains the lock information.

In an LVM configuration, a disk used as a lock disk is not dedicated for use as the
cluster lock, the disk can be employed as part of a normal volume group with user data
on it. A lock LUN, on the other hand, is dedicated to the cluster lock, you cannot store other data on it.

You specify the cluster lock volume group and physical volume, or the cluster lock LUN, in the cluster configuration file.

Rgds...