Troubleshooting

• Most connection issues are fixed by using nower bluez version, minimum 5.50, how to upgrade
• In case of error looking like this:

  File "/usr/local/lib/python3.7/dist-packages/paho/mqtt/client.py", line 3522, in _create_socket_connection
  return socket.create_connection(addr, source_address=source, timeout=self._keepalive)
  File "/usr/lib/python3.7/socket.py", line 727, in create_connection
  raise err
  File "/usr/lib/python3.7/socket.py", line 716, in create_connection
  sock.connect(sa)
  ConnectionRefusedError: [Errno 111] Connection refused
  

  It's a connection problem to provided mqtt server. Double check ip / port / connectivity
• Random bluetooth hangs on rpi3b ( maybe relate to others also ) : https://github.com/raspberrypi/linux/issues/3518