Here's how you can protect your Ubuntu 14.04 system by installing the GUFW firewall.
1. Open a terminal window.
2. Type in the following command then hit Enter.
sudo apt-get install gufw
3. After GUFW is installed, open your Dash and search for GUFW to set it up.
Linux don't need Anti-virus but Firewall is important for any kind of Operating System. UFW is installed by default in Ubuntu but it is command line and disabled by default. You can install best firewall GUFW enable and manage it graphically.More at Noobs Lab
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