Struggling with MQTT and Node Red

Third party integrations Node-RED
1

Hi,

I’m developing a garage door controller in Node-red running on a piZero under Dietpi that I want to connect to my Home Assistant instance using MQTT.

I’m new to MQTT and am still learning, I’m using Node-Red on both ends. The door is subscribed to topic ‘door’ and the HA server to topic ‘doorserver’. Both Node-Red instances are showing as connected in the Node-Red UI .

On the HA instance, I can subscribe to the topic ‘doorserver’ and can receive message sent from the piZero door controller using the mqtt out node sending to topic ‘doorserver’

If I try to send messages from the HA instance to topic ‘door’, I never seem to receive them on the PiZero, despite it being subscribed to the topic ‘door’. If I use an app on my phone, subscribed to topic ‘door’ I see the messages. What could be stopping my PiZero from receiving the mesages, despite the fact that the Node-Red mqtt in node showing as connected?

Thanks
Paul

2

it’s very difficult to answer without seeing the flows. can you post both of them here?
are you able to see messages in Zero when you send it from your mobile with a different topic?

3

The PiZero is working, it seems to be an issue on the HA side.

If I send messages from the mobile app to ‘door’ the PiZero receives them, and it can respond to ‘doorserver’

The HA instance can receive messages on ‘doorserver’, but anything it sends doesn’t seem to be sent.

How do I show you the code behind the flow, I’ve forgotten how to show that, sorry!

4

I dont know what changed but now its working, sorry for the hassle!