[Linux-cluster] GFS upgrade questions

[Kadlecsik Jozsef]

On Thu, 18 Dec 2008, Fabio M. Di Nitto wrote:

> On Thu, 18 Dec 2008, Kadlecsik Jozsef wrote:
> 
> > On Thu, 18 Dec 2008, Fabio M. Di Nitto wrote:
> > 
> > > > We are planning to upgrade our stable - but relative old - GFS1 cluster
> > > > to
> > > > the new version of the stable branch. However as this will be our first
> > > > GFS1 upgrade, it's pretty unknown to us and there are some questions
> > > > about
> > > > it I'd like to ask:
> > > 
> > > Could you be more specific from what version of the software you want to
> > > upgrade to what version?
> > > 
> > > > - Is it possible to upgrade the machines one by one from GFS
> > > >  (cman/fencing/dlm/etc.) point of view?
> > > > - Is it possible to upgrade the machines one by one from the background
> > > >  dependencies (openais, clvmd) point of view?
> > > > - What about an upgrade from a non-corosync-dependent setup to a
> > > >  corosync-dependent one?
> > > > - Should we watch out any new cluster configuration option?
> > > 
> > > I'll be able to answer those questions in details, once you can be more
> > > specific.
> > 
> > This is cluster-2.02.00 with openais-0.80.3.
> > 
> 
> So your best upgrade path is to get latest openais-0.80.X serie and
> cluster-2.03.xx.
> 
> You should be able to upgrade one node at a time without issues. If it doesn't
> work as expected it is a bug so please make sure to notify us ASAP.

We plan to upgrade in the mid of January, first starting with a backup 
node. So if something goes wrong with that single node (and bringing 
it up does not affect the other parts of the cluster) it won't be 
critical. I'll report if the node won't join smoothly to the cluster.

> Upgrade path to a corosync based cluster is not working yet because corosync
> is not on wire compatible with openais at this point in time. It will be
> before 1.0 release. Note that cluster-2.03.xx stable cannot run on top of
> corosync and that cluster-3.0.0.alpha1 is well.. alpha stage and can be buggy.

I see, thank you indeed for clarifying that difference between 
cluster-2.x.x and cluster-3.x.x.
 
> So to answer all your questions (assuming you will go 2.03.xx):
> 
> > > > - Is it possible to upgrade the machines one by one from GFS
> > > >  (cman/fencing/dlm/etc.) point of view?
> 
> Yes.
> 
> > > > - Is it possible to upgrade the machines one by one from the background
> > > >  dependencies (openais, clvmd) point of view?
> 
> Yes.
> 
> Assuming you are using a distribution such as Fedora, both will come down
> together. You will need to rebuild the GFS kernel module manually (depending
> on the distribution)
> 
> > > > - What about an upgrade from a non-corosync-dependent setup to a
> > > >  corosync-dependent one?
> 
> No. This is not an option for you at the moment.
> 
> > > > - Should we watch out any new cluster configuration option?
> 
> It is always a good idea to look at possible new options by looking at the
> changelogs.

That's reassuring, thank you Fabio!

Best regards,
Jozsef
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