Installed Embedded MQTT Broker under Add-ons->Misc
Installed MQTT Binding under Add-ons -> Bindings
Suddenly found MQTT Broker (System MQTT Broker) in Inbox asking to be added as a Thing.
So added that as a Thing
Now addedd a Light Switch as a thing which uses MQTT Using generic MQTT Thing. Bridge was embedded mqtt broker (That was the only thing available in the selection anyway)
Added a Channel to it as ON/Off Switch
Linked to a new item
The Switch is not working and in the log I am getting this message now
2019-03-22 08:59:07.544 [vent.ItemStateChangedEvent] - LightSwitch changed from NULL to UNDEF
What does that mean? It definitely works if all things are online. You have configured a state and/or command topic and know what a state and command topic is in mqtt speech?
I have defined State Topic. When I say switch is not working means, on the control screen I can see the switch. But I cant move the slider towards right to switch on the light. The cursor is still an arrow and doesnt change to “hand”.
Log says 2019-03-22 08:59:07.544 [vent.ItemStateChangedEvent] - LightSwitch changed from NULL to UNDEF
I tried reinstalling all bindingd and Embeded MQTT broker again. Now when I add a channel to a Thing it says internal server error.
Its so unstable
And then I uninstalled everything and installed Mosquitto using openhabian-config. And somehow managed to add a thing and channel and item after a lot of internal server error. It worked for 5 minutes, and now its not working again.
Yes personally I’m using a fork of openHAB core. The extension installation is unstable and the model engine responsible for .things and .item files.
But this is not windows. Don’t uninstall extension. That will not fix anything. Just do a restart of openHAB if in doubt, but that’s also usually not required. (Except if you use .things and .item files)