[Pacemaker] pacemaker-remote container as a clone resource

[David Vossel]

----- Original Message -----
> I'm interested in creating a resource that will control host containers
> running pacemaker-remote. The catch is that I want this resource to be a
> clone, so that if I want more containers, I simply increase the `clone-max`
> property. The problem is that the `remote-node` meta parameter is set on the
> clone resource, and not the children. So I can't see a way to tell pacemaker
> the address of all the clone children containers that get created.
> The only way I can see something like this being possible is if the resource
> agent set an attribute on the clone child when the child was started.
> 
> Is there any way to accomplish this? Or will I have to create separate
> resources for every single container? If this isn't possible, would this be
> considered as a future feature?

I've been keeping up with this thread and just wanted to give my thoughts.

First, lets forget the clone part initially.  Clones and pacemaker_remote don't mix.
I'm not convinced it is advantageous for us to take that conversation much further
right now. Perhaps after start testing this next part we can come back to the cloned
remote-node discussion.

The interesting part here is that you want to define a remote-node that doesn't
have an address. I see this as being highly beneficial. For instance, you want to
make a docker container a remote-node, but docker assigns a random IP to the container
every time it starts... Right now there'd be no (feasible) way to make the docker
container a remote-node because there's no static IP associated with the container.

I think you are dead on about how this should be done. We need a way for the 
container's resource-agent to update pacemaker via an attribute the address
for the container after it has started. From there pacemaker uses that address
when attempting to connect to the container's pacemaker_remote instance.

I've made a issue in the Red Hat bug tracker related to this so I'll remember to do it.
https://bugzilla.redhat.com/show_bug.cgi?id=1139843


-- Vossel






> 
> Thanks
> 
> -Patrick
> 
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