----- Original Message ----- > From: "Andrew Martin" <amar...@xes-inc.com> > To: "The Pacemaker cluster resource manager" > <pacemaker@oss.clusterlabs.org> > Sent: Friday, February 10, 2012 10:33:44 AM > Subject: [Pacemaker] Help with colocation and order of primitives
> Hello, > I am working on configuring a 2-node cluster with 3 DRBD devices, > their corresponding filesystem mounts, and a VirtualDomain resource > agent. I want to add the appropriate constraints to pacemaker so > that these resources only start together on the same node, and that > they start in the proper order. I have added the DRBD devices to a > Master/Slave object, as outlined in > http://www.linbit.com/fileadmin/tech-guides/ha-nfs.pdf . I would > like them to start in the following order (and stop in the reverse > order): > ms_drbd_r0 > ms_drbd_r1 > ms_drbd_r2 > p_filesystem_r0 > p_filesystem_r1 > p_filesystem_r2 > p_virtualdomain_vm0 > I added the 3 filesystem primitives to a group, g_filesystems, which > simplifies this somewhat. Are primitives in a group started in the > order they are listed in a group, and stopped in the opposite order? Yes and colocated in reverse... group test A B C order is A B C colocation is C B A Starts A then B then C, Stops C, B, A. > I read through the Pacemaker Explained documentation on colocation > and order, > http://www.clusterlabs.org/doc/en-US/Pacemaker/1.1/html/Pacemaker_Explained/s-resource-sets-ordering.html It shows XML but when adding via the CRM CLI the rules work the same. The CRM CLI is just a(n easier) front-end for the XML (config is still written in XML) Guide for CRM CLI is here: http://www.clusterlabs.org/doc/crm_cli.html > however it seems to mostly address the XML and not how to add > constraints via the crm console (crm configure). It seems that I > cannot add the Master/Slave objects to a group, so I will need to > specify each of them individual in the constraints. Is it possible > to include more than 2 resources to a constraint, e.g. > colocation c_all_on_one inf: ms_drbd_r0:Master ms_drbd_r1:Master > ms_drbd_r2:Master g_filesystems p_virtualdomain_vm0 Yes you can put more than one primitive in a colocation or order constraint - just be careful when adding multiples of different types of resource. You may want to do "crm configure show xml" to verify the statement didn't create a resource set and change the outcome a little. Also with order statements make sure you specify the action when combining different types otherwise the first action will apply to all resources i.e. ms_drbd_r0:promote g_filesystems:start > Or, can a single colocation or order constraint only contain 2 > resources? If so would I need to chain several constraints together, > like this: > colocation c_r0-r1 inf: ms_drbd_r0:Master ms_drbd_r1:Master > colocation c_r1-r2 inf: ms_drbd_r1:Master ms_drbd:r2:Master > colocation c_r2-fs inf: ms_drbd_r2:Master g_filesystems > colocation c_fs_vm0 inf: g_filesystems p_virtualdomain_vm0 > Which syntax is supported and how can I achieve these colocation and > order constraints? > Thanks, > Andrew > _______________________________________________ > 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
