We are running a heartbeat cluster with several resource groups. One of these groups is depending on a drbd disk which is configured as a master/slave resource.
Everything was working fine with heartbeat v3.0.1 and pacemaker v1.0.7…
Until we upgraded to heartbeat v3.0.3 and pacemaker v1.1.5.
When we tried to swap the resource group depending on the drbd disk, the resource group was stopped but the drbd master / slave resource refused to demote the current master.
Resulting in the unavailability of the resource group.
Mentioning this problem on #linux-ha they pointed me to resource-stickiness in the configuration.
In our configuration the resource-stickiness is set to INFINITY, we have configured it like that because we only want resources to swap during a failure or when manually requested, in all other cases the resource should remain on the node where it currently is. This is not the case when the resource-stickiness is not configured.
Apparently setting it to INFINITY was a bit radical, setting the resource-stickiness to 1000 is sufficient. The resources only swaps during a failure or manually triggered and the drbd master / slave resources follows the resource group using it.