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Exactly, for cinder a/a we would remove it from pacemaker config (as  
recommended) and only define a cluster with zookeeper. I still didn't  
have the time to actually test it properly, but I definitely will.

Zitat von Gorka Eguileor <geguileo at redhat.com>:

> On 22/09, Eugen Block wrote:
>> Hi,
>>
>> thanks for the clarification.
>> We don't set "backend_host" at all at the moment, only "host" to the virtual
>> hostname which has the virtual IP assigned by pacemaker. This seems to work
>> fine.
>
> Hi,
>
> I assume than in an Active-Active deployment you won't be using
> pacemaker, and in that case I would not define "host" at all.
>
> Cheers,
> Gorka.
>
>>
>> > Changing a deployment from Active-Passive to Active-Active is a bit
>> > trickier, because you need to leave one of the cinder-volume services
>> > running (at least once) with the old `backend_host` so it can "move"
>> > resources (volumes/snapshots) to the "cluster".
>>
>> I'm not sure if we'll even try that, I was thinking more about new
>> deployments that would be using active/active from the beginning. If we
>> decided to switch we'd test it heavily before chaning anything. ;-)
>>
>> Thanks again!
>> Eugen
>>
>> Zitat von Gorka Eguileor <geguileo at redhat.com>:
>>
>> > On 31/08, Eugen Block wrote:
>> > > I think I found my answers. Currently I only have a  
>> single-control node in
>> > > my test lab but I'll redeploy it with three control nodes and  
>> test it with
>> > > zookeeper. With a single control node the zookeeper and cinder cluster
>> > > config seem to work.
>> > >
>> >
>> > Hi Eugen,
>> >
>> > Besides deploying the DLM, configuring it in Cinder, and setting the
>> > `cluser` configuration option you should also be careful with the
>> > `host`/`backend_host` configuration option.
>> >
>> > In Active-Passive deployments we set the `backend_host` configuration
>> > option so it is preserved when cinder-volume fails over to a different
>> > controller host, but in Active-Active we actually want each host to have
>> > cinder-volume running with different values, so we usually leave it
>> > unset so it takes the controller's host name.
>> >
>> > Changing a deployment from Active-Passive to Active-Active is a bit
>> > trickier, because you need to leave one of the cinder-volume services
>> > running (at least once) with the old `backend_host` so it can "move"
>> > resources (volumes/snapshots) to the "cluster".
>> >
>> > Cheers,
>> > Gorka.
>> >
>> > > Zitat von Eugen Block <eblock at nde.ag>:
>> > >
>> > > > Hi,
>> > > >
>> > > > I didn't mean to hijack the other thread so I'll start a new one.
>> > > > There are some pages I found incl. Gorkas article [1], but I don't
>> > > > really understand yet how to configure it.
>> > > >
>> > > > We don't use any of the automated deployments (we created our  
>> own) like
>> > > > TripleO etc., is there any guide showing how to setup cinder-volume
>> > > > active/active? I see in my lab environment that python3-tooz  
>> is already
>> > > > installed on the control node, but how do I use it? Besides the
>> > > > "cluster" config option in the cinder.conf (is that defined  
>> when setting
>> > > > up the DLM?) what else is required? I also found this thread [2]
>> > > > pointing to the source code, but that doesn't really help me at this
>> > > > point. Any pointers to a how-to or deployment guide would be highly
>> > > > appreciated!
>> > > >
>> > > > Thanks,
>> > > > Eugen
>> > > >
>> > > > [1] https://gorka.eguileor.com/a-cinder-road-to-activeactive-ha/
>> > > > [2]
>> > > https://www.mail-archive.com/openstack@lists.openstack.org/msg18385.html
>> > >
>> > >
>> > >
>> > >
>>
>>
>>