On 05/12/2012, at 9:05 AM, Lars Marowsky-Bree <l...@suse.com> wrote:
> On 2012-12-04T14:48:50, David Vossel <dvos...@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. Agreed. I'm still torn whether this is a GUI/shell job or something we need to add to the underlying xml. > > 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 > > > _______________________________________________ > Pacemaker mailing list: Pacemaker@oss.clusterlabs.org > http://oss.clusterlabs.org/mailman/listinfo/pacemaker > > Project Home: http://www.clusterlabs.org > Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf > Bugs: http://bugs.clusterlabs.org _______________________________________________ Pacemaker mailing list: Pacemaker@oss.clusterlabs.org http://oss.clusterlabs.org/mailman/listinfo/pacemaker Project Home: http://www.clusterlabs.org Getting started: http://www.clusterlabs.org/doc/Cluster_from_Scratch.pdf Bugs: http://bugs.clusterlabs.org
