topic second cluster lock in Operating System - HP-UX

second cluster lock

Lorenzo Facello — Tue, 04 Nov 2003 06:36:51 GMT

Hi,
I have the FIRST_CLUSTER_LOCK configured on disk /dev/dsk/c3t0d0 with his
alternate link /dev/dsk/c7t0d0 on vgxxx01.
I want to configure the SECOND_CLUSTER_LOCK with this alternate link. Is it possible?
I have to add the strings only in cmclconf file? or anything else???
Regds
L

Re: second cluster lock

melvyn burnard — Tue, 04 Nov 2003 06:47:06 GMT

You cannot use the alternate link of this disc for a 2nd cluster lock disk. What is the point, if the disc goes bad? neither would work anyway.
Do you really need a 2nd cluster lock disc?
HP does not recommend this unless you have 2 or 3 specific scenarios.

Re: second cluster lock

G. Vrijhoeven — Tue, 04 Nov 2003 06:49:39 GMT

L,

Second cluster lock is not possible as far as i know. You can configure a arbitraded node ( QS_HOST, QS_POLLING_INTERVAL QS_TIMEOUT_EXTENTION ). This can be an package on an other HA cluster.

Gideon

Re: second cluster lock

DGH_2 — Tue, 04 Nov 2003 06:57:25 GMT

Hi Lorenzo,
you cannot add a second cluster lock on the same volume group.
if you have a second volume group you can add a SECOND_CLUSTER_LOCK. you add these informations to the cluster configuration file.
for more details see managing MC/ServiceGuard, cluster configuration.
Regards:
Dory

Re: second cluster lock

Ashwani Kashyap — Tue, 04 Nov 2003 09:36:04 GMT

If you have a load balancing software installed and configured like AutoPath or EMC's PowerPath , thay can automatically take care of the alternate link to your First_Cluster_Lock_PV without configuring the second cluster lock .

Re: second cluster lock

Lorenzo Facello — Tue, 04 Nov 2003 10:00:39 GMT

I have 2 node and 1 of these will be stopped
and then also one of CLUSTER_LOCK_VG's link so I need to use another cluster lock on the secondary node.

I would use the alternate link of c3t0d0's SCSI chain
(c7t0d0)on the same vgxxx01.
Do you think it's possible???

Re: second cluster lock

melvyn burnard — Tue, 04 Nov 2003 10:25:00 GMT

Well if you are stopping one of the nodes, i.e. doing a cmhaltnode node1, you will not need the cluster lock disc.
If you are keeping both nodes running, but your link to the cluster lock disc is being shutdown, you then have an issue.
You cannot use the alternate link for the cluster lock disc as this doesnt work.
If you REALLY need to have a 2nd cluster lock disc, it MUST be a completely different physical disc.
The only other way is to use LVM commands to swap the primary and alternate links and hten change the reference in the cluster ascii file to the new path, halt the cluster, reapply the binary, and then restart the cluster and test it.

Re: second cluster lock

Sanjay_6 — Tue, 04 Nov 2003 11:26:56 GMT

Hi,

If the alternate link is the alternate path to the same drive then you cannot use the alternate like as the 2nd cluster lock. On the other hand if the alternate path is a second physical disk, you can use the alternate link as the 2nd cluster lock disk. The two cluster lock disks has to be two seperate physical disks.

you have to add this to the cluster ascii conf file and then apply the changes.

Hope this helps.

Regds