8.4.7. System Upgrades and pacemaker_remote
As of Red Hat Enterprise Linux 6.8, if the
pacemaker_remote service is stopped on an active Pacemaker Remote node, the cluster will gracefully migrate resources off the node before stopping the node. This allows you to perform software upgrades and other routine maintenance procedures without removing the node from the cluster. Once pacemaker_remote is shut down, however, the cluster will immediately try to reconnect. If pacemaker_remote is not restarted within the resource's monitor timeout, the cluster will consider the monitor operation as failed.
If you wish to avoid monitor failures when the
pacemaker_remote service is stopped on an active Pacemaker Remote node, you can use the following procedure to take the node out of the cluster before performing any system administration that might stop pacemaker_remote
Warning
For Red Hat Enterprise Linux release 6.7 and earlier, if
pacemaker_remote stops on a node that is currently integrated into a cluster, the cluster will fence that node. If the stop happens automatically as part of a yum update process, the system could be left in an unusable state (particularly if the kernel is also being upgraded at the same time as pacemaker_remote). For Red Hat Enterprise Linux release 6.7 and earlier you must use the following procedure to take the node out of the cluster before performing any system administration that might stop pacemaker_remote.
Use the following procedure to take a node out of a cluster when performing maintenance on a node running
pacemaker_remote:
- Stop the node's connection resource with the
pcs resource disable resourcename, which will move all services off the node. For guest nodes, this will also stop the VM, so the VM must be started outside the cluster (for example, usingvirsh) to perform any maintenance. - Perform the desired maintenance.
- When ready to return the node to the cluster, re-enable the resource with the
pcs resource enable.
