[ClusterLabs] qnetd and booth arbitrator running together in a 3rd geo site

[Jan Friesse]

Rohit,

> Thanks Honja. That's helpful.
> Let's say I don't use qnetd, can I achieve same with booth arbitrator?

That means to have two two-node clusters. Two-node cluster without 
fencing is strictly no.

> Booth arbitrator works for geo-clusters, can the same arbitrator be reused
> for local clusters as well?

I'm not sure that I understand question. Booth just gives ticket to 
(maximally) one of booth-sites.


> Is it even possible technically?

The question is, what you are trying to achieve. If geo-cluster then 
stonith for sites + booth is probably best solution. If the cluster is 
more like a stretch cluster, then qnetd + stonith is enough.

And of course your idea (original one) should work too.

Honza


> 
> Regards,
> Rohit
> 
> On Tue, Jul 14, 2020 at 3:32 PM Jan Friesse <jfriesse at redhat.com> wrote:
> 
>> Rohit,
>>
>>> Hi Team,
>>> Can I execute corosync-qnetd and booth-arbitrator on the same VM in a
>>> different geo site? What's the recommendation? Will it have any
>> limitations
>>> in a production deployment?
>>
>> There is no technical limitation. Both qnetd and booth are very
>> lightweight and work just fine with high latency links.
>>
>> But I don't really have any real-life experiences with deployment where
>> both booth and qnetd are used. It should work, but I would recommend
>> proper testing - especially what happens when arbitrator node disappears.
>>
>>> Due to my architecture limitation, I have only one arbitrator available
>>> which is on a 3rd site. To handle cluster split-brain errors, I am
>> thinking
>>> to use same arbitrator for local cluster as well.
>>> STONITH is not useful in my case as it is limited only to ILO and VIRT.
>>
>> Keep in mind that neither qdevice nor booth is "replacement" for stonith.
>>
>> Regards,
>>     Honza
>>
>>>
>>> [image: image.png]
>>>
>>> Thanks,
>>> Rohit
>>>
>>>
>>>
>>> _______________________________________________
>>> Manage your subscription:
>>> https://lists.clusterlabs.org/mailman/listinfo/users
>>>
>>> ClusterLabs home: https://www.clusterlabs.org/
>>>
>>
>>
>