How did I fix «Unable to connect to epmd» for RabbitMQ? rabbitmqctl[16077]: DIAGNOSTICS rabbitmqctl[16077]: =========== rabbitmqctl[16077]: attempted to contact: [rabbit@194] rabbitmqctl[16077]: rabbit@194: rabbitmqctl[16077]: * unable to connect to epmd (port 4369) on 194: badarg (unknown POSIX error) rabbitmqctl[16077]: * node name: 'rabbitmqcli-16077-rabbit@194' rabbitmqctl[16077]: * effective user's home directory: /var/lib/rabbitmq rabbitmqctl[16077]: * Erlang cookie hash: c+uWM5j/XbrtAkbQtWa36Q== systemd[1]: Failed to start RabbitMQ broker.

I have fixed it my creating the etc/rabbitmq/rabbitmq-env.conf file with the following contents: