On 08/07/2013, at 11:35 PM, Andrew Morgan <andrewjamesmor...@gmail.com> wrote:
> Thanks Florian. > > The problem I have is that I'd like to define a HA configuration that isn't > dependent on a specific set of fencing hardware (or any fencing hardware at > all for that matter) and as the stack has the quorum capability included I'm > hoping that this is an option. > > I've not been able to find any quorum commands within pcs; the closest I've > found is setting a node to "standby" but when I do that, it appears to have > lost its quorum vote This is not the case. > - this seems at odds with the help text.... > > standby <node> > Put specified node into standby mode (the node specified will no > longer be able to host resources > > Regards, Andrew. > > > On 8 July 2013 10:23, Florian Crouzat <gen...@floriancrouzat.net> wrote: > Le 08/07/2013 09:49, Andrew Morgan a écrit : > > I'm attempting to implement a 3 node cluster where only 2 nodes are > there to actually run the services and the 3rd is there to form a quorum > (so that the cluster stays up when one of the 2 'workload' nodes fails). > > To this end, I added a location avoids contraint so that the services > (including drbd) don't get placed on the 3rd node (drbd3)... > > pcs constraint location ms_drbd avoids drbd3.localdomain > > the problem is that this constraint doesn't appear to be enforced and I > see failed actions where Pacemaker has attempted to start the services > on drbd3. In most cases I can just ignore the error but if I attempt to > migrate the services using "pcs move" then it causes a fatal startup > loop for drbd. If I migrate by adding an extra location contraint > preferring the other workload node then I can migrate ok. > > I'm using Oracle Linux 6.4; drbd83-utils 8.3.11; corosync 1.4.1; cman > 3.0.12.1; Pacemaker 1.1.8 & pcs 1.1.8 > > > I'm no quorum-node expert but I believe your initial design isn't optimal. > You could probably even run with only two nodes (real nodes) and > no-quorum-policy=ignore + fencing (for data integrity) [1] > This is what most (all?) people with two nodes clusters do. > > But if you really believe you need to be quorate, then I think you need to > define your third node as quorum-node in corosync/cman (not sure how since > EL6.4 and CMAN) and I cannot find a valid link. IIRC with such definition, > you won't need the location constraints. > > > [1] > http://clusterlabs.org/doc/en-US/Pacemaker/1.1-plugin/html/Clusters_from_Scratch/_perform_a_failover.html#_quorum_and_two_node_clusters > > > > -- > Cheers, > Florian Crouzat > > _______________________________________________ > 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 _______________________________________________ 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
