Disclaimer: This is dangerous as it might cause a corrupt file system.
This KB should be used with Axcient's Tech Support guidance.
1. Force the system off so grub appears after a dirty shutdown.
2. Hit E on the top line.
3. Scroll down to the line that starts with "linux /boot" and go to the end of it and add "init=/bin/bash" without the quotes
4. Hit F10 to boot
5. When you arrive at the command prompt, type
mount -o remount,rw /
6. Enter your new root password twice
mount -o remount,ro /
7. At this point, you can try 'reboot' or 'shutdown -r now' but if those fail, the power button is the only option. After the system comes back log in as root and:
initctl start asyncreboot
8. The system will reboot again and after that everything should start properly.