paho.mqtt.python ConnectionRefusedError: [Errno 111] Connection refused

Hello, I am using the python paho.mqtt.client to connect with the mosquitto broker installed on the same device. I am getting the connection refused error. The code and the error is like below:

>>> import paho.mqtt.client as mqtt
>>> client = mqtt.Client()
>>> client.connect("192.168.0.13",1883) 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/user/.local/lib/python3.9/site-packages/paho/mqtt/client.py", line 914, in connect
    return self.reconnect()
  File "/home/user/.local/lib/python3.9/site-packages/paho/mqtt/client.py", line 1044, in reconnect
    sock = self._create_socket_connection()
  File "/home/user/.local/lib/python3.9/site-packages/paho/mqtt/client.py", line 3685, in _create_socket_connection
    return socket.create_connection(addr, timeout=self._connect_timeout, source_address=source)
  File "/usr/lib/python3.9/socket.py", line 843, in create_connection
    raise err
  File "/usr/lib/python3.9/socket.py", line 831, in create_connection
    sock.connect(sa)
ConnectionRefusedError: [Errno 111] Connection refused

The mosquitto is loaded and running

$ sudo systemctl status mosquitto
● mosquitto.service - Mosquitto MQTT Broker
     Loaded: loaded (/lib/systemd/system/mosquitto.service; enabled; vendor preset: enabled)
     Active: active (running) since Tue 2022-11-15 11:30:27 +03; 10min ago
       Docs: man:mosquitto.conf(5)
             man:mosquitto(8)
    Process: 2519 ExecStartPre=/bin/mkdir -m 740 -p /var/log/mosquitto (code=exited, status=0/SUCCESS)
    Process: 2520 ExecStartPre=/bin/chown mosquitto /var/log/mosquitto (code=exited, status=0/SUCCESS)
    Process: 2521 ExecStartPre=/bin/mkdir -m 740 -p /run/mosquitto (code=exited, status=0/SUCCESS)
    Process: 2522 ExecStartPre=/bin/chown mosquitto /run/mosquitto (code=exited, status=0/SUCCESS)
   Main PID: 2523 (mosquitto)
      Tasks: 1 (limit: 4643)
     Memory: 980.0K
        CPU: 691ms
     CGroup: /system.slice/mosquitto.service
             └─2523 /usr/sbin/mosquitto -c /etc/mosquitto/mosquitto.conf

Nov 15 11:30:27 user systemd[1]: Starting Mosquitto MQTT Broker...
Nov 15 11:30:27 user systemd[1]: Started Mosquitto MQTT Broker.

$ sudo mosquitto -v
1668501697: mosquitto version 2.0.11 starting
1668501697: Using default config.
1668501697: Starting in local only mode. Connections will only be possible from clients running on this machine.
1668501697: Create a configuration file which defines a listener to allow remote access.
1668501697: For more details see https://mosquitto.org/documentation/authentication-methods/
1668501697: Opening ipv4 listen socket on port 1883.
1668501697: Error: Address already in use
1668501697: Opening ipv6 listen socket on port 1883.
1668501697: Error: Address already in use

$ netstat -a | grep 1883
tcp        0      0 localhost:1883          0.0.0.0:*               LISTEN     
tcp6       0      0 localhost:1883          [::]:*                  LISTEN

I can connect to the broker by using the pub-sub of the mosquitto-clients and see the messages published so I don't think that something is wrong with broker. But the client somehow doesn't connect to it.

Nov 15 '22 08:11 emresoyunmez

Have you tried using localhost instead of your IP address?

Nov 15 '22 09:11 JonathanPlasse

Yes, it doesn't return any errors. But I need this device to work as a bridge between several devices and the client will be handling some processes so I need to make it work with given IP.

Nov 15 '22 09:11 emresoyunmez

1668501697: Opening ipv4 listen socket on port 1883.
1668501697: Error: Address already in use
1668501697: Opening ipv6 listen socket on port 1883.
1668501697: Error: Address already in use

These errors suggest that mosquitto isn't able to open its sockets - perhaps something else is listening already? I don't believe this is a problem with the Python client.

Jan 20 '23 23:01 ralight