[Linux-cluster] frozen services are stopped when rgmanageris restarted

[Martin Waite]

> -----Original Message-----
> From: linux-cluster-bounces at redhat.com
[mailto:linux-cluster-bounces at redhat.com]
> On Behalf Of Tom Lanyon
> Sent: 22 June 2010 07:55
> To: linux clustering
> Subject: Re: [Linux-cluster] frozen services are stopped when
rgmanageris restarted
> 
> On 22/06/2010, at 1:20 AM, Martin Waite wrote:
> > Hi,
> >
> > RHEL 5.4:  cluster2 (I think).
> >
> > I expected to be able to freeze a service on a node and restart
rgmanager on that
> node without interrupting the service.   In practice, starting
rgmanager causes the
> service to be stopped.
> >
> > Is this what is supposed to happen ?  I thought the whole point of
freezing services
> was to allow maintenance (including restarting cluster software).
> >
> > Are there any options to prevent the services from being stopped
when rgmanager
> is started ?
> >
> > One effect of rgmanager stopping the service is that the cluster
reaches an
> inconsistent state.  Once rgmanager has restarted, the cluster
believes that the
> services are still frozen, where in reality they are stopped.   Any
attempt to unfreeze
> the service causes the service to failover to a standby node.
> 
> I did this recently to upgrade rgmanager on a production cluster with
no downtime to
> services, however I can't find the reference materials I used to do
so...
> 
> The basic steps are:
> 
> * freeze all services
> 	/usr/sbin/clusvcadm -Z <service>
> * stop rgmanager
> 	/sbin/service rgmanager stop
> * upgrade rgmanager
> 	yum upgrade rgmanager
> * restart rgmanager manually, using the -N flag
> 	/usr/sbin/clurgmgrd -N
> * wait until rgmanager is running again (check 'clustat' output)
> * unfreeze the services
> 	/usr/sbin/clusvcadm -U <service>
> 
> Tom
> 

Perfect.

Thanks Tom.

regards,
Martin