In order for Pacemaker monitoring to function properly, you must
ensure that RabbitMQ’s .erlang.cookie files are identical on all
nodes, regardless of whether DRBD is mounted there or not. The
simplest way of doing so is to take an existing .erlang.cookie from
one of your nodes, copying it to the RabbitMQ data directory on the
other node, and also copying it to the DRBD-backed filesystem.
node1:# scp -a /var/lib/rabbitmq/.erlang.cookie node2:/var/lib/rabbitmq/ node1:# mount /dev/drbd/by-res/rabbitmq /mnt node1:# cp -a /var/lib/rabbitmq/.erlang.cookie /mnt node1:# umount /mnt
