[Pacemaker] DRBD / KVM / Pacemaker active/active

[Bart Coninckx]

On 10/28/11 12:08, Nick Morrison wrote:
> Hello,
>
> Noob question again.
>
> I keep reading about people running primary/primary drbd pairs with Xen
> on top to do live migration.
>
> Can someone doing so please comment: is this setup safe? How do you
> ensure that the two hosts don't both start the same guest? Does you use
> an external locking mechanism? Or do you use a cluster-aware filesystem?
>
> Cheers!
> Nick
>
>
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I guess the biggest issue is to prevent a DomU to start on both nodes. 
So to be avoided is:

- creating a cluster resource that could do that (clone, master)
- splitbrain => stonith!

What I find a challenge still (see other recent post) is to avoid a 
non-uptodate DRBD resource being promoted to primary and being used by 
the cluster. Either it should not become a master resource, or a 
constraint should exist to avoid it being used. I need to figure that 
one out still.


B.