How to restart KODI without rebooting from Terminal

Hi,
i am trying to use the terminal SSH commands to restart kodi.
But the instructions given in this post (http://forum.kodi.tv/showthread.php?tid=…i+terminal) do not work:

I have tried:

Code:
systemctl restart kodi

but got this answer:

Code:
-bash: systemctl: command not found

What is the correct command?

Server version:

Code:
xbmc@xbmc-server:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 14.04.5 LTS
Release:        14.04
Codename:       trusty