> On 9 Nov 2014, at 9:28 pm, Matthias Teege <matthias-gm...@mteege.de> wrote: > > Hallo, > > On a cluster I have to place three resources on the same node. > > ms ms_disk_R p_disk_R > ms ms_disk_S p_disk_S > primitive vm_srv ocf:heartbeat:VirtualDomain > > The colocation constraints looks like this: > > colocation vm_with_disk_R inf: vm_srv ms_disk_R:Master > colocation vm_with_disk_S inf: vm_srv ms_disk_S:Master > > Do I have to add another colocation constraint to define a > colocation between disk_R and disk_S. I'm not sure because the > documentation says: > > "with-rsc: The colocation target. The cluster will decide where to > put this resource first and then decide where to put the resource in > the rsc field." > > In my case the colocation targets are "ms_disk_R" and "ms_disk_S". > If pacemaker decides to put disk_R on node A and disk_S on node B > vm_srv would not start.
Correct, this is why you need the third constraint - as smart as pacemaker is, its nowhere as good as a human brain. So while it is obvious to us that "ms_disk_R" and "ms_disk_S" need to go on the same node, pacemaker will need the extra hint. Suggestion, do this: colocation disk_S_with_disk_R inf: ms_disk_S:Master ms_disk_R:Master colocation vm_with_disk_S inf: vm_srv ms_disk_S:Master For ordering you want as much parallelism as possible, for colocation - chains work best. > > I use order constraints to start disks before the vm resource. > > order disk_R_before_vm inf: ms_disk_R:promote vm_srv:start > order disk_S_before_vm inf: ms_disk_S:promote vm_srv:start > > Thanks > Matthias > > > _______________________________________________ > 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
