[Pacemaker] RFC: Compacting constraints

[Lars Marowsky-Bree]

On 2009-10-29T16:24:08, Dejan Muhamedagic <dejanmm at fastmail.fm> wrote:

> > There's a bunch of open issues (resource_sets not supporting score="0",
> > the crm shell not supporting resource_sets at all),
> That's on the todo list, I've even started working on it, but then had
> an issue with funny way resource sets are constructed in CIB. We had a
> discussion about that last year.

Can you remind me/us please? Maybe we can fix some of the details still.
I admit I can't find the discussion from last year any more,
unfortunately.

In particular the rsc_order support for resource sets doesn't just not
support score="", but also not the for/then action bits, which I think
might be extremely useful if I want to order several resources after a
master promotion; this also applies to collocation (and I also can't
collocate several resources with a node attribute).

So I think the rsc sets still need a bit of fixing.

> There are no shell constructs which are rendered as two or more CIB
> elements. I guess that this should be possible, but really can't say
> until I take a thorough look at the implementation.

That'd be cool. This would be much within the spirit of the CIB
representing atomic objects and management tools providing higher-level
abstraction.

> BTW, I guess that there are other CIB phrases which are commonly in
> use.

Right, but I think the "order A after B; collocation B with A" is likely
the most common expression; we've got to start somewhere ;-)


Regards,
    Lars

-- 
Architect Storage/HA, OPS Engineering, Novell, Inc.
SUSE LINUX Products GmbH, GF: Markus Rex, HRB 16746 (AG Nürnberg)
"Experience is the name everyone gives to their mistakes." -- Oscar Wilde