[Pacemaker] Dual-Primary DRBD with OCFS2 on SLES 11 SP1

[Vladislav Bogdanov]

05.10.2011 02:30, Nick Khamis wrote:
> Vladislav,
> 
> Thank you so much for your response! Just when I though I hit a wall.
> Perfect timing.
> Actually, I was thinking about setting up a Pacemaker VM Cluster for production.
> The only problem I foresee is stonith. I am not sure if virt is fit
> for production?

I'd say 'yes' if conditions I wrote about are met. Unfortunately, you'll
probably get SPOF with qpid server, at least my trials to get *working*
qpid cluster failed. There are also some API compatibility issues
between qpid releases (from what I remember) which make it impossible to
upgrade to latest qpid if you need fence_virt.

It would be great if somebody write something similar to
fence-virtd-libvirt-qpid, but on top of corosync or ais instead of qpid
(wondering if it is possible at all).

Ah, it still may have some problems while vm's are being migrated,
because then two hosts will list that vm's in qpid, and fence_virt is
not smart enough to deal with that.

Vladislav

> 
> Nick.
> 
> On Mon, Oct 3, 2011 at 3:39 PM, Vladislav Bogdanov <bubble at hoster-ok.com> wrote:
>> Hi,
>>
>> 29.09.2011 17:47, Nick Khamis wrote:
>>> Hello Dejan,
>>>
>>> Sorry to hijack, I am also working on the same type of setup as a prototype.
>>> What is the best way to get stonith included for VM setups? Maybe an
>>> SSH stonith?
>>> Again, this is just for the prototype.
>>
>> You may look at fence-virt.
>> I use fence-virtd-libvirt-qpid (with two my patches which fix grave
>> bugs, names of patches say for themselves) and fence_xvm.
>> It's still not ideal (f.e. it does not work if several hosts know one
>> VM), but it may work well under some circumstances:
>> * You set up qpid server
>> * You run fence_virtd on every host and publish libvirtd data on that
>> qpid server
>> * You ensure that only one host has any VM listed in qpid (read: in
>> virsh list). F.e you unconditionally use virsh undefine after vm is stopped.
>> * You fix its bugs (at least with my patches)
>>
>> Patches are attached.
>>
>> Best,
>> Vladislav
>>
>> P.S. Patches could be also interesting for fence-virt author if he reads
>> this list. It would be great if somebody point him to them otherwise.
>>
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>>
> 
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