On Wed, Mar 16, 2011 at 6:32 PM, Pavel Levshin <pa...@levshin.spb.ru> wrote: > 16.03.2011 10:29, Andrew Beekhof: >> >>> I still don't understand why it monitors services by default on all nodes >>> when the cluster is assymetrical >> >> Because we don't just make assumptions about what the state of the >> cluster is - we verify them. > > Actually, you verify what misconfigured or fake resource agents are saying.
RAs are required to be reliable. Garbage in, garbage out. > Very sane check, indeed. > > Take DRBD for example. Any resource may be configured on no more than two > nodes. If there are more nodes in the cluster, N-2 of them will check for > nothing, fail to check from time to time and cause service instability. > Imagine a highly overloaded or broken node where all, including fake, > resource agents are failing to respond in timely manner. Every service in > such a cluster may suffer from this problem. > > Well, your approach to monitoring is reasonable for symmetrical cluster. > > I beg your pardon if my objections are inappropriate. > > > -- > Pavel Levshin > > > _______________________________________________ > 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://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker > _______________________________________________ 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://developerbugs.linux-foundation.org/enter_bug.cgi?product=Pacemaker