--[ ufw ]

 It should be installed by default in Ubuntu, but if for some reason it’s not, you can install the package using aptitude or apt-get using the following commands:
sudo apt-get install ufw

Check the Status

--[ Ubuntu 14.04 hardening ]

Assume that all these operations need to be performed as root, which you can either do with sudo or by logging in as root first. (I've noticed that Ubuntu users seem particularly averse to logging in as root, apparently preferring instead to issue an endless series of commands starting with sudo, but I'm afraid that kind of extra hassle is not for me, so I just log in as root first.)

Harden SSH