The Rabbitmq failed to start due to the erlang process.
When you diagnose further, you can find below error message:
Oct 10 02:17:09 centos rabbitmq-server[4059]: 2024-10-10 02:17:09.377124-04:00 [error] <0.156.0>
Oct 10 02:17:09 centos rabbitmq-server[4059]: 2024-10-10 02:17:09.377124-04:00 [error] <0.156.0> BOOT FAILED
Oct 10 02:17:09 centos rabbitmq-server[4059]: 2024-10-10 02:17:09.377124-04:00 [error] <0.156.0> ===========
Oct 10 02:17:09 centos rabbitmq-server[4059]: 2024-10-10 02:17:09.377124-04:00 [error] <0.156.0> ERROR: epmd error for host centos: address (cannot connect to host/port)
Oct 10 02:17:09 centos rabbitmq-server[4059]: 2024-10-10 02:17:09.377124-04:00 [error] <0.156.0>
Oct 10 02:17:09 centos rabbitmq-server[4059]: ===========
Oct 10 02:17:09 centos rabbitmq-server[4059]: ERROR: epmd error for host centos: address (cannot connect to host/port)
Oct 10 02:17:10 centos rabbitmq-server[4059]: 2024-10-10 02:17:10.403374-04:00 [error] <0.156.0> supervisor: {local,rabbit_prelaunch_sup}
Oct 10 02:17:10 centos rabbitmq-server[4059]: 2024-10-10 02:17:10.403374-04:00 [error] <0.156.0> errorContext: start_error
Oct 10 02:17:10 centos rabbitmq-server[4059]: 2024-10-10 02:17:10.403374-04:00 [error] <0.156.0> reason: {epmd_error,"hostname",address}
From the error message "cannot connect to host/port",
it likely indicated the Erlang process cannot recognize this hostname or port.
You can use the ping command to test this hostname. You may add this hostname to the /etc/hosts file or make it is resolvable through the DNS.
After we add the host entry in the /etc/hosts file, below is the example in the /etc/hosts file.
1.1.1.1 hostname
the Erlang process is up and the Rabbitmq is running again.