Booted the system adding init=/bin/bash at the end of the kernel line.

Entered Rescue system

Now when trying to restart the system, it appears the message shutdown: Unable to shutdown system

bash-4.1# shutdown -r now
shutdown: Unable to shutdown system
bash-4.1# reboot
shutdown: Unable to shutdown system

To reboot the server, you need to use the following command

bash-4.1# reboot -n -d -f