[Pacemaker] Best stonith method to avoid split brain on a drbd cluster

[Dejan Muhamedagic]

Hi,

On Wed, Jan 05, 2011 at 05:18:36PM -0700, Devin Reade wrote:
> Johannes Freygner <hannes at freygner.at> wrote:
> 
> > *) Yes, and I found the wrong setting:
> 
> Excellent.
> 
> > But if I pull the power cable without a regular shutting down,
> > the powerless node gets status "UNCLEAN (offline)" and the 
> > resources remains stopped.
> 
> I would contend that would be correct behavior as (again assuming that
> you have redundant power sources), the only way that should happen is 
> with multiple failures (against which HA in general does not protect).
> 
> But, it's *your* cluster :)
> 
> > I found and tested a workaround: I use as second fencing device "meatware"
> [snip]
> 
> I would be wary of meatware; I believe that it's intended for testing only.

No, it's not for testing.

> I tried using it in production on one site where the nodes of the HA cluster
> were virtual machines under the free version of VMWare ESXi.  (That version
> has the APIs disabled that would be required to do a proper stonith
> mechanism.) I found that meatware was flakey at best.

If it was flakey, then you ran into a bug. I think that there
were some issues with pacemaker 1.1, but can't recall details
anymore.

Thanks,

Dejan

> As an aside, I will likely never again try to deploy HA nodes as ESXi
> VMs unless the site is running the commercial version.
> 
> Devin
> -- 
> It is far, far better to have a bastard in the 
> family than an unemployed son-in-law.			- Robert Heinlein
> 
> 
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