Multiple MQTT Publish not Working

Question

I have multiple python scripts running that all publish on to different MQTT Mosquitto channels / topics. All scripts start with the following code.

import paho.mqtt.client as mqtt

client = mqtt.Client("python_pub")
client.connect("localhost", 1883)

Then each script has a different publish command like

client.publish("TA/temp", temp)

or

client.publish("timer/time", time)

What happens is if I run one script it will publish successfully I can subscribe with another script.

However, if I run a second script, only the new one will publish. The other falls off.

Do I need to be using different ports or client names between the different python scripts?

Thanks!

Answer 1

The problem is the second line:

client = mqtt.Client("python_pub")

The "python_pub" is the client id and needs to be unique to each client that connects to the broker.