15.8. Failover and Failback of a private container on Linux-HA

EVMS supports the Linux-HA cluster manager in EVMS V2.0 and later; support for the RSCT cluster manager will be made available in a future release of EVMS.

	NOTE
	Ensure that evms_activate is called in one of the startup scripts before the heartbeat startup script is called. If evms_activate is not called, failover might not work correctly.

Follow these steps to set up failover and failback of a private container:

1. Add an entry in /etc/ha.d/haresources for each private container to be failed over. For example, if container1 and container2 are to be failed over together to the same node with node1 as the owning node, add the following entry to /etc/ha.d/haresources:

   node1 evms_failover::container1 evms_failover::container2

   node1 is the cluster node that owns this resource. The resource is failed over to the other node when node1 dies.

   Similarly, if container3 and container4 are to be failed over together to the same node with node2 as the owning node, then add the following entry to /etc/ha.d/haresources:

   node2 evms_failover::container3 evms_failover::container4

   Refer to the following source for more details on the semantics of resource groups: http://www.linux-ha.org/download/GettingStarted.html.

2. Validate that the /etc/ha.d, /etc/ha.cf and /etc/ha.d/haresources files are the same on all the nodes of the cluster.

3. The heartbeat cluster manager must be restarted, as follows, after the /etc/ha.d/haresources file has been changed:

   /etc/init.d/heartbeat restart

   	NOTE
   	Do not add shared containers to the list of failover resources; doing so causes EVMS to respond unpredictably.