[ClusterLabs] Antw: Re: Antw: [EXT] Coming in Pacemaker 2.0.4: shutdown locks

[Ken Gaillot]

On Thu, 2020-02-27 at 22:39 +0300, Andrei Borzenkov wrote:
> 27.02.2020 20:54, Ken Gaillot пишет:
> > On Thu, 2020-02-27 at 18:43 +0100, Jehan-Guillaume de Rorthais
> > wrote:
> > > > > Speaking about shutdown, what is the status of clean shutdown
> > > > > of
> > > > > the
> > > > > cluster handled by Pacemaker? Currently, I advice to stop
> > > > > resources
> > > > > gracefully (eg. using pcs resource disable [...]) before
> > > > > shutting
> > > > > down each
> > > > > nodes either by hand or using some higher level tool (eg. pcs
> > > > > cluster stop
> > > > > --all).  
> > > > 
> > > > I'm not sure why that would be necessary. It should be
> > > > perfectly
> > > > fine
> > > > to stop pacemaker in any order without disabling resources.
> > > 
> > > Because resources might move around during the shutdown sequence.
> > > It
> > > might
> > > not be desirable as some resource migration can be heavy, long,
> > > interfere
> > > with shutdown, etc. I'm pretty sure this has been discussed in
> > > the
> > > past.
> > 
> > Ah, that makes sense, I hadn't thought about that.
> 
> Is not it exactly what shutdown-lock does? It prevents resource
> migration when stopping pacemaker so my expectation is that if we
> stop
> pacemaker on all nodes no resource is moved. Or what am I missing?

shutdown-lock would indeed handle this, if you want the behavior
whenever any node is shut down. However for this purpose, I could see
some users wanting the behavior when shutting down all nodes, but not
when shutting down just one node.

BTW if all nodes shut down, any shutdown locks are cleared.
Practically, this is because they are stored in the CIB status section,
which goes away with the cluster. Logically, I could see arguments for
and against, but this makes sense.
-- 
Ken Gaillot <kgaillot at redhat.com>