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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
>
>
>
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