先检查两个版本的依赖关系
https://www.rabbitmq.com/which-erlang.html
看看RabbitMQ+Erlang和版本是否可以对应上，如果不对，直接卸载重新装，省时省力
/sbin/service rabbitmq-server start
Redirecting to /bin/systemctl start rabbitmq-server.service
Job for rabbitmq-server.service failed because the control process exited with error code. See "systemctl status rabbitmq-server.service" and "journalctl -xe" for details.
查看日志
journalctl -xe
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: Stopping and halting node rabbit@localhost ...
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: Error: unable to connect to node rabbit@localhost: nodedown
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: DIAGNOSTICS
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: ===========
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: attempted to contact: [rabbit@localhost]
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: rabbit@localhost:
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: * connected to epmd (port 4369) on localhost
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: * epmd reports: node 'rabbit' not running at all
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: no other nodes on localhost
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: * suggestion: start the node
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: current node details:
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: - node name: 'rabbitmq-cli-56@localhost'
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: - home dir: .
May 22 13:48:55 localhost.localdomain rabbitmqctl[17004]: - cookie hash: utouIvSvrpZ0+hj89k3ljw==
May 22 13:48:55 localhost.localdomain systemd[1]: Failed to start RabbitMQ broker.
-- Subject: Unit rabbitmq-server.service has failed
-- Defined-By: systemd
-- Support: http://lists.freedesktop.org/mailman/listinfo/systemd-devel
--
-- Unit rabbitmq-server.service has failed.
网上搜了很多
# 删除目录下的文件，无效
/var/lib/rabbitmq/mnesia
# 清空目录下文件，无效
/var/log/rabbitmq
# 检查防火墙，关闭
[root@localhost rabbitmq]# service iptable status
Redirecting to /bin/systemctl status iptable.service
Unit iptable.service could not be found.
都试了，最后发现还不行，查了下安装历史，发现版本依赖关系有问题，从新下了下面图中的版本，重新安装OK
