Unfortunately the Ubuntu server by default doesn’t come with support for .7z, .zip and .rar archive formats installed, meaning that if you want to work with one of these archives then you’re going to have to add it.
Luckily there are packages available to do the work for you, meaning that you simply need to follow the standard install procedure and you should be good to go:
sudo apt-get install p7zip-full sudo apt-get install unrar-free
Quick and easy wasn’t it? :)