----- Original Message ----- > From: "Donald Stahl" <d...@blacksun.org> > To: "Jake Smith" <jsm...@argotec.com>, "The Pacemaker cluster resource > manager" <pacemaker@oss.clusterlabs.org> > Sent: Thursday, February 21, 2013 2:24:59 PM > Subject: Re: [Pacemaker] Dependency Trees > > > I think you may have missed a key piece - Sets. Requires more than > > 2 and assumes at least one will be sequential. > > Not exactly. That may have been a poor example but what I was trying > to achieve was the idea that these 2 services must run on the same > host, but that neither one had to be running, or placed, first. >
I get what your trying for - I was more responding to your example. And I *may* be wrong about requiring more than 2 w/one sequential. > For example- if I create the following: > > colocation OraLsnr03 inf: OraData3 OraBin3 OraIP3 > > # crm_mon -r --one-shot > OraData3 (ocf::heartbeat:Filesystem): Started Host-A > OraBin3 (ocf::heartbeat:Filesystem): Started Host-A > OraIP3 (ocf::heartbeat:IPaddr2): Started Host-A > > All three services are running. But now- if I shut down OraData3: > > # crm resource stop OraData3 > # crm_mon -r --one-shot > OraData3 (ocf::heartbeat:Filesystem): Stopped > OraBin3 (ocf::heartbeat:Filesystem): Stopped > OraIP3 (ocf::heartbeat:IPaddr2): Stopped > > All three services are shut down. If I start OraData3- then all three > resources start back up. > > That was not the behavior I needed because there is a sort of implied > order. > > What I needed to do was put them in ()'s which sets sequential=false > in the XML. > > When I do that- I can stop and start individual services without > affecting the other ones. > > In short- I needed to be able to say: > > These three services must always run on the same host- but not > necessarily started. > > Or perhaps more accurately- If any one of these services is running > on > a host- then the other related services must either be running on the > same host _or_ not running at all. > > colocation OraLsnr03 inf: \( OraData3 OraBin3 OraIP3 \) > > Creates the behavior I have just described. That's great - just to be sure it works as you expect did you try migrating/starting one of the resources on the other node and make sure the others didn't come up on the first node? Jake > > colocation OraLsnr03 inf: OraData3 OraBin3 OraIP3 > > Creates the dependency and ordering behavior I did not want. > > > Here might explain better - have a look at the "Unversioned Docs" > > at 'General Concepts' - ordering explained and colocation > > explained. Well into each of the documents they talk about > > sequential/non-sequential: > > > > http://clusterlabs.org/doc/ > I will give this a more thorough read but I believe I finally have my > head straight. > > Thanks for all of the insight. > -Don > > _______________________________________________ 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
