ls -la /lib/systemd/system/ctrl*

  lrwxrwxrwx 1 root root 13 Aug 30 23:04 /lib/systemd/system/ctrl-alt-del.target -> reboot.target

> sudo rm /lib/systemd/system/ctrl-alt-del.target
> sudo ln -s /dev/null/lib/systemd/system/ctrl-alt-del.target
> sudo systemctl daemon-reload