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

I got Failed to start reboot.target: Connection timed out for my systemctl --force reboot
To ensure that the system will reboot no matter what, I always do this sequence:

# echo s > /proc/sysrq-trigger
# echo u > /proc/sysrq-trigger
# echo b > /proc/sysrq-trigger

This requests the kernel to do:

Emergency sync of the block devices
Mount readonly of all filesystems
Force an immediate boot; you can also use o for poweroff.