[Linux-cluster] rgmanager or pacemaker?

[Patrick Lists]

Hi Madi,

Thank you for your feedback and a special thanks for your 2-Node Red Hat 
KVM Cluster Tutorial. It was very helpful to see how one is built. 
Comments inline.

On 08/19/2013 05:59 PM, Digimer wrote:
> Both options have pros and cons. They can be boiled down to this;
>
> Red Hat (and thus, CentOS) will move to Pacemaker in RHEL/CentOS 7. A
> *lot* of work is happening in RHEL6's pacemaker et. al. to prepare for
> this. As such, pacemaker is in "Tech Preview" mode. What that means is
> that it is not generally supported and it doesn't get updates between
> y-stream releases (6.3 -> 6,4, etc).

Got it.

> Now it's important to note; Pacemaker is and has been production ready
> for a long time. It's just the rapid changes on RHEL 6 specifically that
> make it a moving target. So if you go with Pacemaker, be sure to add the
> clusterlabs.org repo.

I checked the libqb, pacemaker and pcs rpm versions from CentOS 6.4 
versus the ones in the clusterlabs repo. The only one that seems to 
differ is the pacemaker rpm. Did I understand you correctly that, if I 
go for pacemaker, I should use the latest pacemaker (currently 
1.1.9-1512) from the clusterlabs repo? Aka the one listed here:
http://clusterlabs.org/rpm-next/rhel-6/x86_64/

> The biggest argument for rgmanager is that it is well baked and very
> stable/unchanging. Personally, I use it for my RHEL/CentOS 6 clusters
> for this reason. It is fully supported and will remain supported until
> 2020. Now, this said, you would be learning/using a technology that will
> be replaced.

So it boils down to soon-to-be-legacy versus shiny new stuff. Since I'm 
starting from scratch I think I'll go for shiny new stuff :-)

> So to summarize;
>
> Pacemaker is the future but is actively developing/minimally supported
> on RHEL 6.
>
> rgmanager is super stable and fully supported, but will be
> removed/replaced in RHEL 7.

When RHEL7 (CentOS7) goes GA I will be moving to that so I guess it 
makes sense to go for pacemaker. Also it seems pacemaker is better 
documented than rgmanager.

Thank you for your explanation.

Regards,
Patrick