pika.exceptions.ProbableAuthenticationError when trying to send message to remote queue

Question

I'm trying to run RabbitMQ Python tutorial but with sender on virtualbox host machine and receiver and queue on virtualbox guest machine. So I modified mentioned send.py code by only replacing localhost with 192.168.1.5. When I run it, i receive following error:

...
  File "/home/damian/.virtualenvs/kivy_1.9/local/lib/python2.7/site-packages/pika/adapters/base_connection.py", line 153, in _check_state_on_disconnect
    raise exceptions.ProbableAuthenticationError
pika.exceptions.ProbableAuthenticationError

rabbitmq-server seems to be running, because when I stop it send.py gives me:

...
  File "/home/damian/.virtualenvs/kivy_1.9/local/lib/python2.7/site-packages/pika/adapters/blocking_connection.py", line 301, in _adapter_connect
    raise exceptions.AMQPConnectionError(error)
pika.exceptions.AMQPConnectionError: Connection to 192.168.1.5:5672 failed: [Errno 111] Connection refused

which makes perfect sense.

How to fix that ProbableAuthenticationError?

Host machine is Debian 7 with Python 2.7.3 and pika 0.9.14, guest is Ubuntu 15.04 with rabbitmq-server 3.4.3-2

Answer 1

This is because you are trying to authenticate using the username and password guest remotely. Starting with RabbitMQ 3.3 you need to create a new account to use remotely, and guest/guest can only be used locally.

This is taken from the change log here.

25603 prevent access using the default guest/guest credentials except via localhost since (1.0.0)

It's possible to modify the RabbitMQ configuration to allow remote access using the guest account, by removing guest from loopback_users, but it's recommended to create a new user to follow best practices.

[{rabbit, [{loopback_users, []}]}].