After rabitmq is installed normally, rabbitmq server starts normally, but rabbitmq_ The management plug-in failed to start and reported an error:

rabbitmq-plugins enable rabbitmq_management
{:query, :rabbit@web101, {:badrpc, :timeout}}

Solution:
add the Linux host number and host name at the end of the hosts file
method: VI/etc/hosts
Edit by I
host number host name
for example: 192.168.1.1 localhost (fill in your own here)
after adding: WQ save exit
at this time, you can view the rabbitmq plug-in

After rabbitmq is started and the plug-in is also enabled, the page cannot be accessed
the firewall may not be closed

Solution: turn off the Linux firewall

(1) Set boot enable firewall: systemctl enable firewalld.service

(2) Set boot disable firewall: systemctl disable firewalld.service

(3) Start firewall: systemctl start firewalld

(4) Turn off the firewall: systemctl stop firewalld

(5) Check firewall status: systemctl status firewalld