----- Original Message ----- > From: "Sven Arnold" <sven.arn...@localite.de> > To: pacemaker@oss.clusterlabs.org > Sent: Saturday, March 9, 2013 4:43:38 PM > Subject: [Pacemaker] Ordering Constraint: Difference Between Stop and Migrate? > > Dear all, > > Is it possible with ordering constraints to distinguish stopping a > resource from migrating it to another node?
Take at look at this issue and the comment I posted. http://bugs.clusterlabs.org/show_bug.cgi?id=5055#c3 I've looked into this in great detail. At the moment you have encountered a limitation of policy engine. Hopefully someday we can fix this. The solution to this problem is unfortunately somewhat complex. -- Vossel > I think it is not possible since the resource manager would need to > know > the "migration downtime" in advance but anyways I will give it a try: > > Given two resources A and B consider the following cases: > > 1) A and B are stopped > > When A is started, B is not affected > When B is started, A has to be started before > > 2) A and B are started > > When A is stopped, B has to be stopped before > When B is stopped, A is not affected > > But: > When A is migrating to another node (and thus stopped temporarily), B > shall keep running. > > The most appropriate rule would be: > > order A_before_B 0: A B > > but it would not help enforcing stopping B when shutting down A for > more > than a short period. > > > The use case I have in mind is having a shared storage (DRBD, iSCSI > Target) with configured failover on two nodes and an iSCSI Initiator > and > other services on other nodes. I would like to keep the dependent > services running during a planned migration of the storage. And I > would > like to have a "correct" order configured when shutting down > services. > > Best regards, > > Sven > > _______________________________________________ > 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
