[ClusterLabs] Antw: Changes coming in Pacemaker 2.0.0

[Andrei Borzenkov]

On Thu, Jan 11, 2018 at 10:54 AM, Ulrich Windl
<Ulrich.Windl at rz.uni-regensburg.de> wrote:
> Hi!
>
> On the tool changes, I'd prefer --move and --un-move as pair over --move and --clear ("clear" is less expressive IMHO).

--un-move is really wrong semantically. You do not "unmove" resource -
you "clear" constraints that were created. Whether this actually
results in any "movement" is unpredictable (easily).

Personally I find lack of any means to change resource state
non-persistently one of major usability issue with pacemaker comparing
with other cluster stacks. Just a small example:

I wanted to show customer how "maintenance-mode" works. After setting
maintenance-mode=yes for the cluster we found that database was
mysteriously restarted after being stopped manually. It took quite
some time to find out that couple of weeks ago "crm resource manager"
followed by "crm resource unmanage" was run for this resource - which
left explicit "managed=yes" on resource which took precedence over
"maintenance-mode".

Not only is this asymmetrical and non-intuitive. There is no way to
distinguish temporary change from permanent one. Moving resources is
special-cased but for any change that involves setting resource
(meta-)attributes this approach is not possible. Attribute is there,
and we do not know why it was set.