A Firewall is an essential tool for protecting a computer network from several threats by filtering the inbound and outbound traffic. There are lots of open-source firewalls for this purpose. But Open Source Firewall doesn’t mean that it is entirely free to use. Instead is distributed under a license that allows the user access to the source code. Users can use this source code to develop their firewall or even use the pre-developed ones.
But whatever the theory be, an Open Source firewall will save you bucks from buying a paid variant. There are lots of such firewalls available to download from the internet. But Linux users may find it challenging to find one as many Linux-based Firewalls have discontinued their services. So, to help you, we have made a list of the best open-source Firewalls for Linux users.
Also Read- Best Free Firewall for Windows
List of Best Open-Source Linux Firewalls in 2021
- Untangle Firewall
This is a default Firewall management tool for RHEL, CanvO S, SUSE, and OpenSUSE. Firewalld is a popular firewall among Linux users and also has dynamic support for networks. The interface of the Firewall is straightforward.
The main features of Firewalld include D-Bus API, IPV4, IPV6, bridge, and IPset support. Moreover, it allows configuring its setting using the firewall end terminal.
If you are a new user of Linux based Firewall, the UEF w will be a perfect option for you. The main features of UFW enclosed IPv6 support, status monitoring, etc. Additionally, it allows its user to add, remove or alter Firewall rules.
UFW also includes GUI and GUFW for Ubuntu and Debian users.
Iptables is the most famous name in the Firewall domain. It is such a firewall that enables you to rearrange rulesets. Most of the advanced Linux admins trust this terminal-based firewall for its efficiency and customization. But that doesn’t mean that novice users will not be able to use it.
Some of the unique features of Iptables include packet filter ruleset, implementation and inspection of a packet header for fast output, editable ruleset, etc. You can also use it for data backup and restoration.
It is one of the most trusted open-source Firewalls based on FreeBSD custom kernel. pfSense features a high-level packet filtering that gives complete security over networks. However, the most exciting aspect of the firewall is that it is available in many formats, starting from hardware devices to downloadable editions.
A summary of the advanced feature offered by pfSense includes load-balancing for inbound and outbound traffics, compatible with DNS and DHCP server, etc. Apart from its free version, pfSense also comes in a premium version for commercial purposes.
5. IpCop Firewall
Another firewall that allows flexibility and scalability in the firewall ruleset is IpCop Firewall. It is almost identical to Iptables and can be used interchangeably, but the features in IpCop Firewall are much more advanced than Iptables.
The advanced features of this firewall include a network-specific virtual machine, enhanced performance through maps and connotations, etc. IpCop Firewall Also features a unified and consistent Syntax to support the protocol.
Endian is a high-security firewall for complete network protection and packet inspection. The developers of Endian claim that the firewall can convert a simple machine into robust security, spam alert, etc. As a result, users have also ensured network security, spam alert, etc. In addition, users have also ensured web security through a URL blocklist.
Some of the best-in-class features of endian can be classified into real-time network monitoring, bidirectional network security, spam alert, etc.
If you are looking for an easy-to-use firewall for small office or personal use, IPFire is a good option. The firewall includes content filtering, multi-deployment facilitation, and a built-in intrusion detection system. Additionally, you can use it as a VPN gateway or proxy server.
Many Linux users trust the firewall for its accessible and dynamic settings. Thus, IPFire is a perfect companion for providing network security.
It is another easy-to-use and easy to build Linux Firewall based on Hardened BSD. You will get most of the premium security features in OPNSense free of cost. Moreover, the firewall gets weekly updates so that there is no deficiency or loopholes left behind.
Along with the general features, some additional features of offense include forward caching proxy, traffic shaping, intrusion detection, and VPN. The robust build and various features make it one of the most desirable firewalls for Linux users.
9. Untangle Firewall
Untangle is an open-source Firewall based on Debian 8.4. You will get basic network functions for free. The Firewall provides all the functions through a well-managed web-based user interface. Untangle was initially names NG Firewall and is trusted by advanced Linux admins.
Some additional features of Untangle Firewall include Spam, Phishing and Virus blocker, Intrusion prevention, Adblocker, etc. It can be easily installed on any hardware or virtual machine or bought a device with an NG Firewall preinstalled.