topic Re: cluster lock disk in Operating System - HP-UX

cluster lock disk

simon_164 — Fri, 11 Aug 2006 05:18:23 GMT

I am building a cluster and I decided to keep the cluster lock disk a 1GB disk alone created from EVA. this lock disk does not seem to be activated on whatever node, however when i remove the heartbeat, everything happens as expected.
Is it normal that the cluster lock disk will not be activated? I don't have any lv on it.
What do you advice?

Re: cluster lock disk

melvyn burnard — Fri, 11 Aug 2006 05:20:31 GMT

The cluster lock disc does not hav eto be activated to be useable. It MUST be activated at the time of creating teh cluster and writing the cluster lock bits to it, but from then on it does need to be activated.
If you have a dedicated CL disk and VG,not activated by any package, then this would be normal

Re: cluster lock disk

Steven E. Protter — Fri, 11 Aug 2006 05:24:03 GMT

Shalom,

This points to a few possible issues:

1) The cluster lock disk does not get "activated" When heartbeat is lost both nodes attempt to establish a lock on it. The first node achieves it, the one second one if it tries should fail and TOC, wish is a reboot with a crash dump.

2) There will be no noticable disk activity on the cluster lock disk when a cluster uses it so dont look for a flashing green light.

3) The possible problem maybe a prolbem the the configuration on both nodes not being consistent, the binary configuration files being different or perhaps you have two heartbeats and disrupting one does not trigger any cluster change.

You need to look at /var/adm/syslog/syslog.log on both systems when testing and that will provide you some clue as to what is happening.

SEP

Re: cluster lock disk

simon_164 — Fri, 11 Aug 2006 05:26:56 GMT

steven: this is what is happening, while testing -- one node TOCed and the other worked fine. which is what is expected. but i was asking since I am making a cluster lock disk alone. By the way how would i know if the lock bit is created on the disk? any command?

Re: cluster lock disk

Steven E. Protter — Fri, 11 Aug 2006 05:47:53 GMT

Shalom,

Very iteresting. I've never checked that.

http://docs.hp.com/en/B9903-90035/B9903-90035.pdf

Its a linux doc but it has a reference to the cluster lock disk and bit, and may contain the command you seek.

The way I tell the cluster lock disk has been activated is the second node going TOC on me.

SEP

Re: cluster lock disk

melvyn burnard — Fri, 11 Aug 2006 06:17:12 GMT

>By the way how would i know if the lock bit is created on the disk? any command?

Not easy!
This is written in the Bad Block Relocation area of the disk (hence the reason you cannot mirror this bit).
When you start your cluster running, it polls teh configured disc from each node at start time an dthen every 60 minutes.
If the bit were NOT set, it would log the cluster lock disc as unavailable in syslog.log.