[Pacemaker] Migration atomicity

[Lars Marowsky-Bree]

On 2012-03-20T11:42:08, Andrew Beekhof <andrew at beekhof.net> wrote:

> > I'm observing a little bit unintuitive behavior of migration logic when
> > transition is aborted (due to CIB change) in the middle of the resource
> > migration.
> >
> > That is:
> > 1. nodea: migrate_to nodeb
> > 2. transition abort
> > 3. nodeb: stop
> > 4. nodea: migrate_to nodec
> 
> I'd like to see that a crm_report showing that behavior.
> Because I'm looking at the same scenario and I see:
> 
> 1. nodea: migrate_to nodeb
> 2. transition abort
> 3. nodea: stop
> 4. nodeb: stop
> 5. nodec: start

Yes, that's what I see and expect too.

What would obviously be very nice is if the PE could reconstruct that a
migration is on-going and allow it to complete first, before again
shuffling the resource to where it now believes it should be. (To avoid
service downtime.) I wonder how hard that'd be? ;-)


Regards,
    Lars

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