Hiya,
Replies also in-line;
On 19/08/13 14:03, Patrick Lists wrote:
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.
Woot! Glad it was helpful.
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/
You should actually grab the 1.1.10 release from git and use it to build
the RPMs. 1.1.10 has many important fixes.
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 :-)
Entirely valid decision.
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
If you are learning and do not plan to go into production until
RHEL/CentOS 7 is out, then I would recommend using Fedora 19 for your
testing and learning. RHEL 7 is expected to be based on Fedora 18/19 and
pacemaker 1.1.10 is a different beast on EL6 vs EL7/F19.
I've _started_ work on a 3rd tutorial that will be based on Pacemaker /
EL7. It's *extremely* incomplete and in very early in development, but
seeing as you're starting out, I suppose it can't hurt.
https://alteeve.ca/w/AN!Cluster_Tutorial_3
Of course, feedback is always appreciated. :)
--
Digimer
Papers and Projects: https://alteeve.ca/w/
What if the cure for cancer is trapped in the mind of a person without
access to education?
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