[Pacemaker] colocation that doesn't

[Tim Serong]

On 11/25/2010 at 10:33 AM, Alan Jones <falancluster at gmail.com> wrote: 
> Instead of: 
> > 
> >  colocation resX-resY -2: resX resY 
> > 
> > Try: 
> > 
> >  colocation resX-resY -2: resY resX 
> > 
>  
> That works fine, as you describe, for placing resY when resX is 
> limited by the -inf rule; but not the reverse. 
> In my configuration the -inf constraints come from an external source 
> and I wish place resX and resY in a symmetric way. 
> Start with resX and resY which can run on either nodeA or nodeB. 
> Give each a preferred node respectively; a "weak" preference. 
> Now request that, if possible, they should run on different nodes; 
> potentially overriding the "weak" node preference. 
> Now add external constraints that prohibit one or other from running 
> on one or the other node. 
> For example, if any one of the resources is prevented from running on 
> its preferred node, it should run on the non-preferred node and push 
> the other resource onto its non-preferred node. 
> I have not figured out how to express this in pacemaker. 

Ah, OK.  I'm not seeing it either.

Can you elaborate on why you want this particular behaviour?  Maybe
there's some other way to approach the problem?  (Or maybe someone else
can think of a way to express this...)

Regards,

Tim


-- 
Tim Serong <tserong at novell.com>
Senior Clustering Engineer, OPS Engineering, Novell Inc.