How can I reboot a server with systemctl if systemctl reboot fails?

I tried rebooting my CentOS 7 server but it gives ridiculous error messages. As root (of course): # systemctl reboot Authorization not available. Check if polkit service is running or see debug message for more information. Failed to start reboot.target: Connection timed out See system logs and 'systemctl status reboot.target' for details. Exit 1 Does polkit need to check whether root has the right to reboot the machine??? If so, why? # systemctl status reboot.target ● reboot.target - Reboot Loaded: loaded (/usr/lib/systemd/system/reboot.target; disabled; vendor preset: disabled) Active: inactive (dead) Docs: man:systemd.special(7) Exit 3 Do I need to enable the reboot target? Why would this be disabled by default? Perhaps this will work? # systemctl start reboot.target Authorization not available. Check if polkit service is running or see debug message for more information. Failed to start reboot.target: Connection timed out See system logs and 'systemctl status reboot.target' for details. Exit 1 OK, force it, then: # systemctl --force reboot Authorization not available. Check if polkit service is running or see debug message for more information. Failed to execute operation: Connection timed out Exit 1 And the server is still up.