Setting up a firewall is key to securing your network perimeter. A firewall blocks sensitive ports and filters incoming and outgoing traffic to thwart malicious connections and ensure there is no unsolicited exchange of data.

In the world of FOSS, there are plenty of firewall solutions to choose from. Here's a list of the best firewall solutions for fortressing your network on Linux.

1. Uncomplicated Firewall (UFW)

UFW or Uncomplicated Firewall is the default firewall solution on Ubuntu and many prominent Linux distributions. It uses the Netfilter framework, a built-in component of the Linux kernel, to monitor and manage network traffic.

If you’re a beginner and are looking for free and easy-to-use firewall software with basic features, you can adapt to using UFW since it's readily available on your system. All you need to do is invoke it and implement your configurations.

2. IPFire

ipfire website home page

IPFire is a free, secure, and open-source firewall distribution. It is not a software package but an entire operating system. Initially, it was distributed as a fork of the IPCop project. As of now, it has grown into a standalone operating system based on Linux From Scratch (LFS).

IPFire offers a minimal approach and an intuitive color-coded user interface. Beginners will find it very easy to navigate the system and configure it to their requirements.

Besides featuring firewall features, IPFire offers additional capabilities to detect and mitigate intrusion and also functions as a VPN. If you need a feature-packed, dedicated, and lightweight firewall solution and are on a tight budget, you can rely on IPFire.

3. OPNsense

opnsense website home page

OPNsense is an open-source, FreeBSD-based firewall distribution offering a free and a paid subscription-based OPNsense Business edition. It is an advanced firewall system offering a multitude of additional features besides monitoring and managing network traffic.

Some of OPNsense's flagship features include the ability to deeply analyze network packets, filter web traffic, and tackle external threats with an inline Intrusion Detection System (IDS).

Along with these lucrative capabilities, what makes OPNsense the go-to choice of many is its easy-to-use web interface, documentation, and multilingual support. If you are looking for a serious, advanced network security solution, you can place your faith in the richness of the OPNsense firewall system.

4. Endian Firewall (EFW)

endian firewall website homepage

Endian Firewall is an open-source plug-and-play stateful firewall distribution. It is available as free software or paid software if you wish to enjoy customer support. It is equipped with real-time packet monitoring capabilities, antivirus, website statistics logging, and more.

EFW is highly flexible and you can configure it for home and enterprise users alike. It can construct a highly secure and scalable network perimeter.

5. Shorewall

shorewall website home page

The Shorewall software, much like UFW, is a firewall interface that operates on the Netfilter framework to monitor and filter network traffic. It's open source and free to use. Unlike the rest of the firewall solutions mentioned (except UFW), Shorewall doesn't require dedicated hardware or virtualized containers to work.

You can simply download and install the software package and implement it. While Shorewall is a very simple piece of software, don't underestimate its capabilities as it is highly configurable and when working with rapidly changing network environments, Shorewall is quick to adapt.

6. pfSense

pfsense website home page

pfSense is a FreeBSD-based open-source firewall platform. It is also the parent project from which OPNsense was forked. This is why there are many foundational similarities between pfSense and OPNsense. pfSense delivers advanced network security and intrusion detection and you can deploy it as a router, DHCP, or DNS server.

It is highly configurable and flexible in its application. Moreover, the highly accessible web control center makes it very easy to manage the pfSense system and get a complete overview of the security stature of the network perimeter.

Owing to its history, pfSense is well-documented to help new users get familiar with the environment. The commercial edition of pfSense firewall offers training sessions as well.

7. ConfigServer Security and Firewall (CSF)

configserver firewall website homepage

ConfigServer Firewall (CSF) is a free, cross-platform, and versatile stateful firewall solution. CSF offers a plethora of features. From tracking processes and sensitive services logins to setting up custom email alerts whenever the system detects suspicious connections, you can configure CSF to do just about anything that a firewall should do and much more.

Since it is a highly advanced firewall solution, it's recommended that only sysadmins or technically sound users adopt this firewall into their network.

8. Smoothwall

smoothwall website homepage

Smoothwall is a free and open-source security-hardened firewall distribution. It is one of the advanced firewall solutions that come equipped with features like real-time traffic monitoring, web content filtering, emergency record management, and more. While it is free software, you can also purchase commercial editions of Smoothwall if need be. The pricing for the commercial edition is quote-based.

9. Vuurmuur

vuurmuur website home page

Similar to UFW and Shorewall, Vuurmuur is a free and open-source firewall utility that makes use of in-built firewalling components of the Linux kernel like iptables and Netfilter to manage the network perimeter. It offers an intuitive graphical user interface (GUI) layout to configure the firewall.

Vuurmuur lies in the gray area between being minimal and at the same time feature-rich. Its GUI makes it accessible to casual users and as it is entirely scriptable, you can easily implement your automation scripts.

10. ClearOS

ClearOS firewall website homepage

ClearOS is an open-source CentOS-based firewall distribution. While its flagship editions are paid products, there is a no-cost and free-to-use community edition that you can download and deploy right now. ClearOS, unlike other firewall solutions of its stature, is relatively easy to install and configure.

Once you have installed ClearOS, you can get to configuring it via the easy-to-navigate web-based control panel. What's even better, ClearOS is a widely used software and hence, is well documented. If you stumble upon any issues with ClearOS, a read of the documentation will surely resolve your conflicts.

Secure Your Home Network With the Right Tools and Configurations

You shouldn't take network security lightly. An intruder with unsolicited access to your network can monitor your movement on the internet and potentially hijack your devices or worse, your virtual identity.

While securing your network may come off as a tedious task requiring technical expertise, in reality, a secure network is built upon basic digital hygiene and a few important configurations in how you connect to the internet. Learn more about how you can set up a secure network at home.