MQTT Broker offline


i have openhab installed in a docker at my QNAP NAS system.

Curently I would like install the MQTT 2.5.4 Binding to install a MQTT Broker with that I can communicate with my flashed Sonoff tasmota.

But I get only the status of the MQTT Boker “offline”.

What could be the reason?

Thx for all hints.


You did install a MQTT broker ( like Mosquitto) to which your MQTT broker thing would connect, correct?
How did you configure this thing, via text-file( I faintly remember the need of a restart around your used version) or via PaperUI?
Did you try it with the real IP instead of

I configure MQTT broker via PaperUI. As IP-Adress I tok also the real ip address in.
But both ip addresses or “localhost” don’t work and the things shows “offline”

I think you’ve got a basic misunderstanding.

An MQTT broker stands outside of the openHAB framework. The Sonoff talks to the broker, openHAB binding talks to the broker.

Sonoff <-> broker <-> openHAB

The broker is separately installable, put it where you like. Choosing the mosquitto broker package and installing on the same box alongside openHAB is a common practice.

The MQTT binding ‘Broker Thing’ is just a pointer for the openHAB binding to use to connect to the actual broker.

Perhaps I had to open a new thread, but my problem belongs to the same topic.
After two years of my openhab system, I decided to change the OS version to Stretch (Raspian)
Release = Raspbian GNU/Linux 9 (stretch)
Platform = Raspberry Pi 3 Model B Rev 1.2
openHAB 2.5.9-1 (Release Build)
And with openhabian-config I updated the system and the packages, but after that, It seems there is no connection between the broker (mosquitto) and openhab, i.e. I have another NodeMCU that communicates in 433mhz with various devices, sending and receiving messages via MQTT; the PI receives the messages (I checked with a MQTT client), but openHAB does not receive the data.
I use different topic for each device, with many items similar to the next one (broker is the name of the broker)

DateTime DataOraNow "[%1$td.%1$tm.%tY %1$tH:%1$tM]" {mqtt=">[broker:dateTopic:state:*:default]"}

and rules acting on the ground of the received or to be sent message.
But now no message received or sent to openHab. Logs do not provide any information (or better any information I recognize pertinent for my issue)
Any idea?