[ClusterLabs] PAF resource agent & stickiness - ?

[Jehan-Guillaume de Rorthais]

On Sun, 11 Apr 2021 16:03:34 +0100
lejeczek <peljasz at yahoo.co.uk> wrote:

> On 10/04/2021 16:19, Jehan-Guillaume de Rorthais wrote:
> >
> > Le 10 avril 2021 14:22:34 GMT+02:00, lejeczek <peljasz at yahoo.co.uk> a
> > écrit :  
> >> Hi guys.
> >>
> >> Any users perhaps experts on PAF agent if happen to read
> >> this - a question - with pretty regular 3-node cluster when
> >> node on which "master" runs goes down then cluster/agent
> >> successfully moves 'master' to a next node.  
> > How did you take down the node ?
> > And what are the scores at this time ?  
> It still boggles my mind, not being an expert though for a 
> while have 'pacemaker' run in my setups, how relationships 
> and dependencies between resource work.
> I've had another resource which I preferred to hold to a 
> specific node and also colocation constraint where that 
> resource was to run with vIP of pgsqld
> 
>   HA-10-3-1-226 with HA-10-1-1-226 (score:INFINITY) 
> (id:colocation-HA-10-3-1-226-HA-10-1-1-226-INFINITY)
> 
> HA-10-1-1-226 is pgsqld's
> 
> logic of that just brakes my mental health :)
> So cancel and mark as non-existent the issue I originally 
> raised.
> many thanks, L.

Colocation with infinite score might be tricky to understand, depending on what
resource must colocate with the other one (or the other way around), with what
other properties, etc.

A quick quote from doc:

  > Remember, because INFINITY was used, if B can’t run on any of the cluster
  > nodes (for whatever reason) then A will not be allowed to run. Whether A is
  > running or not has no effect on B.

Regards,