Rabbitmq has some issues which caused the whole OpenStack outage, here is a place to track all the possible critical bugs/fixes.
Handshake timeout https://bugs.launchpad.net/ceilometer/+bug/1337715
Timed out waiting for a reply via rabbit https://bugs.launchpad.net/oslo.messaging/+bug/1338732
RabbitMQ connections lack heartbeat or TCP keepalives https://bugs.launchpad.net/bugs/856764
Bug watches keep track of this bug in other bug trackers.
Handshake timeout /bugs.launchpad .net/ceilometer /+bug/1337715
https:/
Timed out waiting for a reply via rabbit /bugs.launchpad .net/oslo. messaging/ +bug/1338732
https:/