pfSense – Overview, Features, and Installation Guide

Is your computer prone to attacks or do you value important data on your devices that you want them kept away from hackers or potential attackers? If so, you need to be equipped with a reliable and efficient firewall.

In this case, we highly recommend pfSense as your go-to firewall as it is one of the fastest and most reliable firewalls you can find on the internet. The best part of it all is that its free.

What is pfSense?

pfSense may not sound familiar to you, but it has been out for a couple of years. You may have heard about it in some IT forums or from software engineers. But what is pfSense?
pfSense is basically an open source firewall that allows distribution of the router with the basis of the FreeBSD.Ina deep sense. The term pfSense is basically an outcome of its capability of making the OpenBSD packet filtering system pf more accessible and more convenient to those who are not very technically well versed.

pfSense is set to be used on a computer and is proven to provide excellent and well-balanced functions that are only seen in more expensive high-end flame surfaces. Luckily, pfSense can be further enhanced and advanced by means of a web interface which does not require data from the real FreeBSD system in order to access.

pfSense is usually used for the following purposes: Advantage Software, Hub, Access for Wireless Means, Host Server for DHCP web as well as DNS and also, as the endpoint for VPNs.

It is completely free of charge and can be personalized using a FreeBSD in order to be used as a software as well as a hub. Moreover, aside from being truly efficient and convenient for users, pfSense also provides a more secure and versatile firewalling and redirecting feature.

It is equipped with several program systems that enable more versatility without bringing along a lot of bloatware and possible security lapses on its base circulation. Ever since its emergence in 2004, several users have been using its features.

These users range from those setting up miniscule home computer systems trying to defend a PC or a console from possible attacks to large multinational companies defending their system from potential attackers.

pfSense was first derived from the m0n0wall software but has evolved to be used in PC systems as opposed to those components targeted by m0n0wall. Aside from the above-mentioned features, pfSense also provides lightweight, portable displays.

What are the different features offered by pfSense?

pfSense has been popular among several users as well as in the IT industry because of the myriad of features it offers. Here are some of the features it offers.


One of the main purposes of pfSense is providing a firewall. It makes your system secure by filtering each source as well as IP address, protocols and destination ports for traffic of UDP and TCP. It also minimizes the occurrence of simultaneous connections on a ruling basis.

In addition, pfSense makes use of p0f which is a highly advanced passive operating system which allows you to filter through the OS which is initiating the network connection. If ever you want to allow FreeBSD and Linux computers to access the internet but at the same time block Windows machines, pfSense does this without a sweat. It does this by passive detection of the operating system that is running.

It also gives you the option whether to log on or not on traffic matching. It provides a versatile policy routing through the selection of gateways based on rules. This is useful for load balancing and when using multiple WANs.

pfSense also allows grouping as well as the naming of IP through different aliases. This will come in handy when keeping the firewall ruleset devoid of bloat. It also makes it easier to understand especially in instances where there are several public IPs and servers.

This software is also capable of Layer 2 Transparent Firewalling. This means that it can connect interfaces as well as filter traffic between these two interfaces. It also allows access of an IP less firewall.

State Table

pfSense allows for a stateful firewall. This means that the stable table can be able to maintain and store data on your open connections. This is really important since most firewalls fail to provide full control over your stable table. With the use of pfSense, you will gain access to several features that provide fine control on your stable table. This is possible through the FreeBSD’s ported edition of pf.

With the use of pfSense, you also get different stable table sizes. This means that you can gain access to a multitude of production pfSense installations with the use of several states. Depending on the RAM equipped on the system, the default stable size may vary. It is worth noting that for every state, it consumes 1 KB of RAM. With that being said, make sure to keep track of the RAM consumption when choosing the stable table size.

To make things efficient, pfSense limits simultaneous connections to clients, host states, amount of connections every second. It also determines state timeout as well as state type.
pfSense also is able to determine state type and provides several options for handling of states.

The keep state feature is able to work with most protocols. A sloppy state is able to function with all protocols, although state tracking is minimized. This will come in handy in asymmetric routings.

Moreover, the synproxy state allows incoming TCP connections in order to enhance protection of servers from questionable TCP SYN floods. This feature is able to combine the purpose of keep state as well as modulate state.

Network Address Translation (NAT)

pfSense allows port forwarding which includes ranges and the usage of several public IPs. The default configuration would direct outbound traffic into WAN IP. In cases of multiple WANs, the default settings reroute the NAT outbound traffic towards the IP of the WAN interface that is running. Advanced Outbound NAT is capable of disabling the default feature and is also capable of creating a more flexible NAT. NAT Reflection, on the other hand, is also accessible so that the services be operated by nonprivate IP from inner networks.

High Availability

Due to a combination of Pfsync as well as CARP, the pfSense is able to provide a capable and high availability function. With pfSense, you get access to two or more firewalls which can be used as a fail-safe group. For example, if one of the interfaces fail or when the primary one turns offline, the secondary saves the day and activates itself. Moreover, pfSense provides configuration synchronization capabilities to make things more customizable depending on your prioritized firewall.

In this case, the stable table of the firewall is being replicated to the different fail safe firewalls. When this happens, the connections that are currently running will be kept in the good performance in case of failures.


pfSense allows Multi-Wan functionality. This means that the software allows access to the several internet connections with the presence of load balancing and failover. This further enhances the stability of the connection as well as efficient distribution and usage of your bandwidth.

Server Load Balancing

Another feature offered by pfSense is server load balancing. This way, the load is distributed towards several servers. This will come in handy when maintaining web servers, mail servers and such. Those servers who are not able to respond to requests for ping or on connections for TCP Port are then removed out of the pool.

Virtual Private Network (VPN)

pfSense also provides two options in terms of connectivity to VPN. These are IPsec as well as OpenVPN. IPSec is a kind of VPN which permits connection to any device which has a support for the standard IPSec. This type of VPN is usually used when connecting from site to site as well as connection to other pfSense installations aside from other types of firewall solutions. Mobile connectivity is also possible using IPsec.

Open VPN, on the other hand, is another type of VPN which provides a versatile and efficient SSL VPN solution which supports a vast array of client OS.

PPPoE Server

Aside from VPN, pfSense can also provide a server for PPE. This type of server is used as a database for the purpose of authentication as well as RADIUS verification with possible accounting support.

Reporting and Monitoring

pfSense can also let you identify the processes so that you can manage historical data. It does this through presenting graphs and tables. These graphs show CPU usage, total throughput, states of the firewalls, Interface throughputs, interface packet usage, the response of ping of Wan interface gateways, traffic ques as well as real-time data. While historical data is important, it also pays to determine real-time data. In order to do this, pfSense makes use of SVG graphs.

Dynamic DNS

pfSense also provides a Dynamic DNS which allows you to register your public IP to a myriad of dynamic DNS service provider. It also provides a client which is responsible for RFC 2136 dynamic DNS update.

Captive Portal

With the use of pfSense, you also get access to a captive portal. A captive portal gives you permission to have authentication as well as redirection to a certain page through a simple click to give you access.

Captive portals are usually used on hotspot networks. However, it can be also applied to large networks in order to provide added security for their wireless or wired connections.

Why should you use pfSense instead of other firewalls?

We know that there are several firewalls abounding the internet, however, pfSense stands above the rest because of its fast, efficient and stable performance as well as the ton of useful features it is equipped with. With that being said, we highly recommend users and even large corporations to use pfSense.

Thousands of large corporations, universities and even government agencies have been enjoying the benefits of pfSense. This alone is a testament to how this firewall is able to provide security even to the larger bodies that are prone to attacks.

How to Install pfSense

Installing pfSense on your computer or other device is fairly simple. Here we will provide you with a concise series of steps so that you can get started with pfSense.

  1. The first thing you need to look into is choosing the installation type. Before doing so, you also need to be mindful of the minimum hardware requirements in order to use pfSense.
    • pfSense requires at least a 64 bit Intel or AMD processor which also has support for AES-NI.
    • The computer must also boot from a USB or any other optical drive in order to install the program. There is support for 32-bit processors but for pfSense versions 2.4 and up, you need a higher configuration.
  2. You also need to choose whether you will install using an ISO installer, through Memstick or a Memstick Serial.
    • ISO installers are easy to use and are much more familiar with most users. If your computer has an optical drive, then this is the best route to go to. This will come in handy for computers who cannot boot from USB also.
    • MemStick is much like an ISO but instead of using CDs, you can run the installer through a USB thumb drive. This method is typically faster and useful for those computers with no optical drives. Serial Memstick, on the other hand, is similar to the former but it runs with the use of a serial console instead of a VGA. This is used for newer systems.
  3. The next step is to download pfSense. You can do this by visiting their website or by clicking this link: You need to pick your preferred version as well as installer type. Afterward, download the SHA256 file in order to identify the image. Choose a mirror link and then download the image from this link. When this is done, you need to wait for the download to finish.
  4. The next part is to prepare the installation media. Depending on the type of installer, the downloaded image must be copied to your preferred installation media. For embedded files, you need to make use of a disk which contains the OS.
  5. When you have already written the image to your targeted installation media, you need to connect this to your serial console. Before you attempt to install it, you must first connect it to the serial console with the correct cable and terminal accessories.
  6. When this is done, you are ready to perform a full install. Just power on the computer or device and connect the installer media. Depending on the type of installer, you choose, the steps may vary. Luckily, the installer is equipped with instructions that guide you throughout the process.

There you have it. With pfSense, you don’t need to be constantly on the lookout for possible attacks. Just install pfSense and watch it do its magic.