[Linux-cluster] recommended method for changing quorum device

[Mark Hlawatschek]

Mark,

without guarantee ;-) I believe that the following method should work:

1. make sure that all 3 nodes are running and part of the cluster
2. stop qdiskd on all nodes (#service qdiskd stop)
3. create new quorum disk (#mkqdisk ...)
4. modify cluster.conf
5. #ccs_tool update /etc/cluster/cluster.conf
6. start qdiskd on all nodes (#service qdiskd start)

Kind regards,
Mark


----- bergman at merctech.com wrote:

> I've got a 3-node RHCS cluster and the quorum device is on a SAN disk
> array that needs to be replaced. The relevent versions are:
> 
>       CentOS 5.6 (2.6.18-238.9.1.el5)
>       openais-0.80.6-28.el5_6.1
>       cman-2.0.115-68.el5_6.3
>       rgmanager-2.0.52-9.el5.centos.1
>       
> 
> Currently the cluster is configured with each node having one vote
> and
> the quorum device having 2 votes, to allow operation in the event of
> multiple node failures.
> 
> I'd like to know if there's any recommended method for changing the
> quorum disk "in place", without shutting down the cluster.
> 
> The following approaches come to mind:
> 
>       1. Create a new quorum device (multipath, mkqdisk).
> 
>          Ensure that at least 2 of the 3 nodes are up.
> 
>          Change the cluster configuration to use the new path to
>          the new device instead of the old device.
> 
>          Commit the change to the cluster.
> 
>       2. Create a new quorum device (multipath, mkqdisk).
> 
>          Ensure that at least 2 of the 3 nodes are up.
> 
>          Change the cluster configuration to not use any quorum
>          device.
>          
>          Commit the change to the cluster.
>          
>          Change the cluster configuration to use the new quorum
>          device.
> 
>          Commit the change to the cluster.
> 
>       3. Create a new quorum device (multipath, mkqdisk).
> 
>          Change the cluster configuration to use both quorum
>          devices. 
> 
>          Commit the change to the cluster.
> 
>             --------------------------------------------------
>             Note: the 'mkqdisk' manual page (dated July 2006)
> 	    states:
>                   using multiple different devices is currently
>                   not supported
>             Is that still accurate?
>             --------------------------------------------------
> 
>          Change the cluster configuration to use just the 
>          new quorum device instead of the old device.
> 
>          Commit the change to the cluster.
> 
> Thanks for any suggestions.
> 
> Mark
> 
> --
> Linux-cluster mailing list
> Linux-cluster at redhat.com
> https://www.redhat.com/mailman/listinfo/linux-cluster

-- 
Mark Hlawatschek

ATIX Informationstechnologie und Consulting AG | Einsteinstrasse 10 |
85716 Unterschleissheim | www.atix.de 

http://www.linux-subscriptions.com