Local Mosquito broker and ESP32 does not connect

[MasoudHasany]

Hi All,

I would like to see sensor data using Node-red and a local MQTT (mosquito) server. I installed everything and could connect mosquito to node-red, publish and receive data.
When I use 127.0.01 and port 1883 to connect ESP32 to my local mosquito, I receive the below error:

Attempting MQTT connection...failed, rc=-2 try again in 5 seconds

I read about 20 threads on the net about the error and did every solution people suggests. However, no success up to now.

Can someone help me out?

Thank you

[Idahowalker]

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Bread board power rail split

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[MasoudHasany]

Hello Idahowalker,

I think I did not cross any rules in Arduino Forum. The error I inserted in my first message is copied from my "serial monitor". Please let me know if I did something wrong.
Thanks

[mikb55]

You need to use the external IP address (not 127.0.0.1) that Mosquitto.is listening on.

[MasoudHasany]

Thank you. And where i can find that external ip?

[mikb55]

By default Mosquitto will listen on all active wired and wireless interfaces, so try one of those. A valid IP address will probably start with the numbers 192, 10, or 172 depending on how your network has been setup.

If that doesn't work then look in the mosquitto.conf file to see how the
# Listeners
section has been configured.
If it has been set to use a particular address, then use that.

[Idahowalker]

Has the OP used a 3rd party application, like MQTT.fx, to successfully connect to their MQTT Broker?

Has the OP tried to use the name of the MQTT server instead of the IP address?

OP, the code?

[MasoudHasany]

Hi mikb55

I run a netstat through CMD and I could these IPs:

But non of them works.

[MasoudHasany]

Sorry. But what is the OP?

[mikb55]

If you are using the latest version of Mosquitto you may be running into this problem networking - Mosquitto: Starting in local only mode - Stack Overflow

Scroll down to where it says
listener 1883

[Idahowalker]

I refer to OP as the Original Poster.