[ClusterLabs] Antw: Re: Q: ordering clones with interleave=false

[Ken Gaillot]

On Thu, 2018-08-30 at 08:28 +0200, Ulrich Windl wrote:
> > > > Ken Gaillot <kgaillot at redhat.com> schrieb am 29.08.2018 um
> > > > 20:30 in
> 
> Nachricht
> <1535567455.5594.5.camel at redhat.com>:
> > On Wed, 2018‑08‑29 at 13:30 +0200, Ulrich Windl wrote:
> > > Hi!
> > > 
> > > Reading the docs I have a question: WHen I run a clone with
> > > interleave=false in a three‑node cluster, and the clne cannot be
> > > started on one node, will ordering for such a clone be possible?
> > > Does
> > > it make a difference, whether the resource cannot run on an
> > > online
> > > node, or is unable due to a standby or offline node?
> > > 
> > > Regards,
> > > Ulrich
> > 
> > Interleave=false only applies to instances that will be started in
> > the
> > current transition, so offline nodes don't prevent dependent
> > resources
> > from starting on online nodes.
> 
> Ken,
> 
> thanks for responding and explaining. However as I read about "the
> transition
> thing" more than once in an answer: Where is that concept explained
> in greater
> detail?

Good question, it's not. There are additions such as a Troubleshooting
chapter planned for the new "Pacemaker Administration" document, when
that mythical available time appears, and that would be a good place
for it.

A transition is simply the set of actions Pacemaker plans in response
to a new situation. The situation is defined by the CIB (including
status section). Whenever something interesting happens (configuration
change, unexpected action result, or cluster re-check interval), the
scheduler uses the current live CIB to calculate what (if anything)
needs to be done, and that is a transition.

> 
> Regards,
> Ulrich
-- 
Ken Gaillot <kgaillot at redhat.com>