Mqqt update

Setup, Configuration and Use Items & Sitemaps
1

Hey,

I use the 2.5 Mqtt binding for linking the KNX addresses to the MQTT bus.
However, when the status of 1 output changes, the status of the other outputs is also sent immediately. This gives a considerable load on the MQTT broker.

Who can help with this so that only the status of the other is sent with an update of 1 output?

Items file

Switch Output_1 “Output_1 [%s]” (Test) { channel=“knx:device:9d0e2d38:2”, channel=“mqtt:topic:mybroker:satelthing:output_1” [profile=“follow”]}
Switch Output_2 “Output_2 [%s]” (Test) { channel=“knx:device:9d0e2d38:1”, channel=“mqtt:topic:mybroker:satelthing:output_2” [profile=“follow”]}

Mqtt things

    // Uitgangen

    Type switch : output_1 "Output_1" [ stateTopic="output_1", commandTopic="output_1/state", postCommand="true" ] 
    Type switch : output_2 "Output_2" [ stateTopic="output_2", commandTopic="output_2/state", postCommand="true" ]
2

And the KNX channels / things?

We can begin an analysis of your MQTT setup.

If a message is received with topic xxx/output_1, the MQTT binding will both update the Item Output_1 and send a command to it.

That command will get sent to the KNX binding, and we don’t know what happens there yet. I can see

The MQTT binding ignores Item state changes.
But that Item command will also get sent to the MQTT binding, where it will get sent out using topic xxx/output_1/state.

I don’t think this message on xxx/output_1/state will be seen as looping back in xxx/output_1, but not sure about that?

In openHAB, the incoming command will trigger autoupdate, which is set on for your Items by default, and that will make another Item state update.

Meantime, you have set a follow profile on your MQTT channel. I don’t think it does anything useful, as you have failed to give any profile-parameterID= to go with it. I suppose there is a chance that the follow profile will default to following the same Item, and enter a screaming loop.
Perhaps you need to look at what you put that there for?