Im using Hassbian 0.96.5 and until this afternoon it worked fine.
Quick power cut, and after a reboot - I have no MQTT functionality.
I use the Hassbian built in broker and define the broker address, username, password within config.yaml
But now, when I look at my overview - i have a raft of unavailable entities due to MQTT.
The log shows this
Config entry for mqtt not ready yet. Retrying in 80 seconds.
I did manage to ssh to the pi and run mosquitto -v
and it works - as long as the ssh terminal remains open - when I close it - it all stops again.
So it appears that the Hassbian MQTT broker isnt running by default ?