MQTT Problems after Backup from OH2.5 to OH3

Hi everybody,

I was running an OH2.5 instance in an VM that just keeps getting bigger and eats up all the HDD space. I therefore wanted to start semi new, created a new VM (Ubuntu 20.04 running) and decided to switch to OH3.

  1. Created new VM
  2. installed Ubuntu20.04
  3. installed OH3 (through apt)
  4. installed Mosquitto2.0.6
    4.1. modified the mosquitto.conf (added listener 1833 and allow_anonymous true)
  5. installed InfluxDB2.0.3
    5.1. created openhab and grafana user and openhab bucket with openhab user RW access and grafana with Read access
  6. backed up my OH2.5 instance
  7. restored that backup on the OH3 system


  • the Tradfri, LG WebOS, Openweathermap, Network, Astro, systeminfo, and DWDunwetter bindings are working.


  • The MQTT binding seems to not communicate with the Mosquitto server, although the broker and all items are shown with a green “online” icon.

To test if the importing of the backup would be the problem, i created a new “MQTT Broker” (Things->MQTT Binding->MQTT Broker) added a new Generic MQTT Thing and added a switch channel (client is a tasmotized plug).
This is also shown as “online” but does not represent the current state, nor does it send a command to the mosquitto server.
The messages from the clients are received by the Mosquitto server (checked with “MQTT Explorer”) but the Mosquitto server receives no command from the Openhab server.

[Edit]: I have no error messages in the openhab or event logs. The mosquitto.log also shows no errors. [/Edit]
What could be the problem an how would i solve this?

I noticed that the imported mqtt things have an identifier mqtt:topic:thingname whereas the things created through the UI have an identifier mqtt:topic:brokername:thingname. Does this have any impact an needs to be changed?

Thank you for any help and thanks to the developers for their time and effort on this project.

Can you show us the configuration of this UI-created Thing and Channel? Just copy/paste from the Code tab of the Thing. Can you also show us the MQTT Parameters page from your Tasmota device?

of course:
Tasmota config page:

Mqtt Broker:

`UID: mqtt:broker:MQTT-Test
label: MQTT Broker
thingTypeUID: mqtt:broker
lwtQos: 0
publickeypin: true
keepAlive: 60
clientid: ca5d7ded-9d3b-40aa-94f9-07c879a54703
qos: 0
reconnectTime: 60000
host: localhost
secure: false
certificatepin: true
lwtRetain: true
enableDiscovery: true
location: Server´

MQTT Thing:

`UID: mqtt:topic:MQTT-Test:Waschmaschine
label: WaschmaschineTEST
thingTypeUID: mqtt:topic
configuration: {}
bridgeUID: mqtt:broker:MQTT-Test
location: Bad

  • id: WaschmaschineTEST
    channelTypeUID: mqtt:switch
    description: “”
    commandTopic: BD/cmnd/Waschmaschine/POWER
    stateTopic: BD/stat/Waschmaschine/POWER`

:face_with_symbols_over_mouth: :man_facepalming:
Found the Problem myself:
I had set up the openhab VM, cloned it and used the cloned VM from there on.
With the MQTT Explorer i monitored the old VM and not the new one and the Clients published to the old VM.
It could not work.
Sorry for that and thanks @hafniumzinc for the quick reply. (very interesting name BTW)