1. Environment:

centos 7.3

2. Problem description

Today, the following error occurred in the process of deploying rabbitmq as a front-end and back-end message push

$ rabbitmqctl set_permissions -p/duni ".*" ".*" ".*"

Error: unable to connect to node rabbit@bbbbdddd: nodedown

DIAGNOSTICS
===========

attempted to contact: [rabbit@bbbbdddd]

rabbit@bbbbdddd:
  * connected to epmd (port 4369) on bbbbdddd
  * epmd reports node 'rabbit' running on port 25672
  * TCP connection succeeded but Erlang distribution failed

  * Hostname mismatch: node "rabbit@localhost" believes its host is different. Please ensure that hostnames resolve the same way locally and on "rabbit@localhost"


current node details:
- node name: 'rabbitmq-cli-92@bbbbdddd'
- home dir: /var/lib/rabbitmq
- cookie hash: h6TDjQ+DgPaVGJLMjcG4TA==

I can’t connect to the host where I deployed rabbitmq bbbbdddd

3. Google

Google found the corresponding problem in stack overflow

Here we say to give rabbitmq command permission, delete the service and then re install it. After trying, I found that I can’t do it…

Continue with Google, and some people say to correct Erlang’s Cookie:

Erlang will generate two cookie files: C: windows. Erlang. Cookie and C: user. Erlang. Cookie. Check whether the contents of the two files are consistent. If not, replace one with the other.

Windows platform, er… My environment is Linux, and I didn’t find two . Erlang. Cookie files in the root directory

$ find/--name .erlang.cookie
/var/lib/rabbitmq/.erlang.cookie

So I gave up.

4. Solutions

The final solution is to set the host name and restart the rabbitmq service

# Kill the rabbitmq process first
$ ps -ef | grep rabbitmq | grep -v grep | awk '{print $2}' | xargs kill -9

# set hostname (assume host ip is: 192.168.1.1, hostname set to: mq)
$ echo 192.168.1.1 mq > /etc/hosts
$ echo rabbitmq > /etc/hostname
$ export HOSTNAME=mq

# Restart rabbitmq
$ rabbitmq-server -detached
# Start the web socket service
$ rabbitmq-plugins enable rabbitmq_management rabbitmq_web_stomp
# Set up users and give them administrator privileges
$ rabbitmqctl add_user duni duni
$ rabbitmqctl set_user_tags duni administrator
# set user directory
$ rabbitmqctl set_permissions -p/duni ".*" ".*" ".*"