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Brief Setup on Ubuntu UFW

As security is elusive ever since mankind invented encryption methods. It is important to set some form of wall to keep some marauding data thieves out of the walled 'data' garden. The old timeless saying of 'better late than never' rings true in this context.

A firewall is a basic protection for personal consumers since the late 1990s when internet usage becomes prevalent. In Ubuntu 16.04, the firewall typically consists of UFW (Uncomplicated Firewall). There is a graphical front-end but if you prefer to use commandline or your
computer is in need of more computing resource, the UFW is your preferred choice.

This brief is on setting up Ubuntu UFW using the gnome console or terminal using relatively simple rules (in comparison to setting up the Linux Firewall using iptables).

As an average user, we need to open certain ports to access the internet. Without a firewall, the 'attack surface' (as security commentators commonly use it to label the 'connection loopholes' that cyber 'predator' discover to 'listen' on its 'prey' ) is big enough to break into and is detrimental to your internet security.

The list of TCP and UDP and its concomitant service description can be found on the Wikipedia here.  If you are curious to know more in depth, you can go to the Internet Assigned Numbers Authority website (IANA website) to read further on the ports available.

To add rule to allow incoming access to your network, we execute the command:

sudo ufw allow 993/tcp

To delete rule that you have added, we execute the command:

sudo ufw delete allow 993/tcp

To add rule to allow outgoing access to the external network, we execute the command:

sudo ufw allow out 465/tcp

Similarly, to delete the outgoing rule we have added above, we execute:

sudo ufw delete allow out 465/tcp

To view the status of the UFW rules we have added to date, we execute:

sudo ufw status

That's all for today!

Attached is a screenshot of the UFW Rules (v6 stands for ipv6) and you can check /etc/default/ufw for the configuration:


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