Celery: consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 92] Protocol not available

Question

I keep getting this error, and I don't know why. I'm using Ubuntu on Windows 10 and celery used to work fine. Then something happened and I keep getting this error. I use celery docs to learn.

Here is the task.py:

from celery import Celery

app = Celery('tasks', broker='pyamqp://guest@localhost//')

@app.task
def add(x, y):
    return x + y

Here the error that I'm getting:

[2017-08-14 17:34:04,436: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 92] Protocol not available.
Trying again in 2.00 seconds...

[2017-08-14 17:34:06,453: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 92] Protocol not available.
Trying again in 4.00 seconds...

[2017-08-14 17:34:10,465: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 92] Protocol not available.
Trying again in 6.00 seconds...

[2017-08-14 17:34:16,480: ERROR/MainProcess] consumer: Cannot connect to amqp://guest:**@127.0.0.1:5672//: [Errno 92] Protocol not available.
Trying again in 8.00 seconds...

In order to start Celery I type:

celery -A tasks worker --loglevel=info

Answer 1

Did you recently update amqp?

It seems that connecting to a RabbitMQ instance from a Linux subsystem is not possible anymore since versions past 2.1.2 du to socket witchery.

https://github.com/celery/py-amqp/issues/145

I suggest trying other backends that Celery might support, I'm going to try redis. Downgrading to at least RabbitMQ 2.1.2 could possibly solve the problem too.