[Pacemaker] Enable remote monitoring

[Lars Marowsky-Bree]

On 2012-12-04T14:48:50, David Vossel <dvossel at redhat.com> wrote:

> The resource ordered set with the 'restart-origin' option gets us half way there in the constraint definition.  We still have to build the colocation set between the vm and the resources so everything runs on the same node (perhaps I just assumed that was necessary, correct me if I am wrong)

Right, we end up with two resource sets.

(Unless we allow the "restart-origin" to be set for the order
constraints that are implicit if a colocation resource set is used with
sequential=true. Ouch.)


> The above is "usable", but it requires the user to explicitly set up
> and manage multiple constraint definitions.  It seems to me like we
> will eventually want to simplify this process.  When that time comes,
> I just want to make sure we approach building the simplified
> abstraction at the configuration level and have the management tools
> (crm/pcs) be a transparent extension of whatever we come up with.

For what it is worth, I'd agree with this; the fact that the most common
constraints are order *AND* colocation and we don't have a
(link|chain|join) statement that adequately provides that has been
annoying me for a while. ;-) I massively appreciate that we do have the
separate dimensions, and people use that - but still, the combination of
both is extremely common.

The independent order + colocation statements do allow for that though;
and in theory, a frontend *could* detect that there's both "A first,
then B" and "B where A is" with the same priority and present it merged
as:

	join id-494 inf: A B



Regards,
    Lars

-- 
Architect Storage/HA
SUSE LINUX Products GmbH, GF: Jeff Hawn, Jennifer Guild, Felix Imendörffer, HRB 21284 (AG Nürnberg)
"Experience is the name everyone gives to their mistakes." -- Oscar Wilde