Getting Started with OPNsense. A Beginner's Guide - zenarmor.com (2024)

The OPNsense story began in 2014, when it split off from pfSense® and m0n0wall. Its official debut was in January 2015, and since then, it's been on a fast-paced evolution while preserving the best of both m0n0wall and pfSense.

OPNsense started out as a simple fork of pfSense, but it has since blossomed into a robust alternative to pfSense as a standalone firewall. Today, OPNsense stands as one of the most potent open-source firewalls and routing platforms you can get your hands on.

OPNsense is different because it has features that are on an equal level with or better than those found in expensive commercial firewalls. Not only does it work, but it does so in the open and honest way that open source is known for. A strong dedication to security and excellent code quality is at the heart of this development.

OPNsense doesn't leave you hanging when it comes to security. It delivers weekly security updates in small, timely increments to address emerging threats swiftly. Plus, it follows a fixed release cycle, dropping two major releases each year. This predictability empowers businesses to plan their upgrades proactively.

For every major release, OPNsense makes a roadmap that guides work and spells out clear goals. This careful approach makes sure that OPNsense stays a strong, reliable, and always-evolving firewall solution.

We can now take a closer look at OPNsense after briefly talking about how it originated and how it has grown. Because it would be too hard to cover everything under each heading, we will refer to your previous sense articles when we need to. There, you will be able to find a lot of information.

This article will talk about a number of things, such as:

• What is OPNsense?
• Why is the OPNsense firewall essential for network security?
• What are the basic system requirements for OPNsense?
• What steps are involved in the initial setup of OPNsense?
• What are the key elements of the OPNsense user interface?
• What are firewall rules, and why are they important?
• What is network and port forwarding work in OPNsense?
• What security features does OPNsense offer to protect a network?
• What is a VPN, and why might beginners want to set up one with OPNsense?
• What are the best plugins every OPNsense user should have?

What is OPNsense and its History?​

OPNsense is an open-source, FreeBSD-based firewall and routing software developed by Deciso, a Dutch business that manufactures hardware and sells support packages for OPNsense. OPNsense is a branch of pfSense, which was forked from the FreeBSD-based m0n0wall. OPNsense went live in January of 2015.

The history of OPNsense started with the release of m0n0wall, an ambitious project that aimed to create firewall software based on FreeBSD. The main selling points of m0n0wall were compatibility with embedded PCs and older hardware and an easy-to-use web interface powered by PHP. It was a solid start, focusing on Layer 3 and Layer 4 firewalling.

However, some network and security administrators were craving more features. They wanted things like web proxying, intrusion detection, and prevention systems. Commercial firewalls were offering these features as part of a Unified Threat Management (UTM) solution.

So, in 2004, a new project was born: a fork of m0n0wall. This new kid on the block was named pfSense. As the name suggests, it utilized Packet Filter (PF) instead of IPfilter, which was its predecessor's packet filter. pfSense gained a dedicated community and constantly improved over time. Even those who had been loyal to Linux-based firewalls started making the switch to this FreeBSD-based firewall.

Both m0n0wall and pfSense coexisted for several years until 2015, when m0n0wall was discontinued. The signs of discontent were there: license changes and the project's direction left part of the pfSense community unhappy.

In 2014, a group of determined developers decided to take matters into their own hands. They forked from both pfSense and m0n0wall, giving birth to OPNsense in January 2015. While it inherited a lot of code from its predecessors, OPNsense had a grand vision to change how things were done.

OPNsense quickly emerged as a worthy pfSense alternative, and its reputation got a significant boost when Manuel Kasper, the founder of m0n0wall, recommended his community migrate to OPNsense. It marked the beginning of one of the most exciting open-source firewall projects.

Why is the OPNsense firewall essential for network security?​

Due to the abundance of valuable data, hackers have historically targeted businesses and government institutions. Nevertheless, as the boundaries between our physical and digital realms blur and remote work becomes the new normal, home networks have emerged as enticing prospects for cybercriminals.

A prominent menace to home networks is malware. An exemplary case is the Mirai botnet, a malicious software that capitalizes on vulnerable IoT devices to create 'zombies' or botnets. These botnets can then be wielded to launch colossal DDoS attacks, leading to substantial disruptions in internet services.

Another challenging adversary is ransomware, wherein hackers encrypt files and demand a ransom for their decryption. The infamous WannaCry attack in 2017 left numerous home computer users grappling with a dilemma: pay an exorbitant ransom or bid farewell to their cherished files.

In addition to malware and ransomware, phishing scams ensnare unsuspecting users into revealing personal information, while Wi-Fi hacking entails attackers gaining access to your network by exploiting weak Wi-Fi passwords. All these risks underscore the critical need for a robust home network security system.

Your quest to enhance cybersecurity may start with other open-source or paid firewall solutions. However, you might encounter issues as it can introduce instability into your network.

Being a powerful open-source firewall and routing platform, OPNsense provides ways to combat these threats and improve home network security. OPNsense can detect and block unwanted behavior by evaluating incoming and outgoing communications, defending against malware and lowering IoT-related risks. Intrusion Detection and Prevention Systems (IDPS) can detect malware patterns and behaviors, providing an additional layer of protection. OPNsense prevents access to known harmful websites in order to combat ransomware. Frequent data backups help to lessen the impact of ransomware. OPNsense stops phishing websites with features like DNS filtering, and email filtering helps detect and quarantine phishing communications. Enhancing Wi-Fi security using strong passwords and, if available, WPA3 support offers an extra degree of protection. The VPN capabilities of OPNsense provide safe remote access, while regular software upgrades keep the system secure. A complete security policy must include user education and community support. You may efficiently protect your home network against various cyber attacks by leveraging these solutions and OPNsense's characteristics, resulting in a secure digital environment in this age of distant work and growing security problems.

What are the basic system requirements for OPNsense?​

Having highlighted the significance of OPNsense in bolstering network security, it's time to shift our focus to understanding the fundamental system requirements necessary to begin your journey with this robust open-source firewall.OPNsense is packed with features, including a stateful firewall, an intrusion detection system (IDS), and web content filtering. OPNsense can be deployed on a variety of hardware platforms, from physical servers to virtual machines.

Here are the fundamental system requirements for OPNsense:

• Processor: 1 GHz dual-core CPU
• Memory: 4 GB RAM
• Storage: 40 GB SSD or HDD (more storage may be required for additional features or packages.)
• Network interface: 1 or more network interfaces

In addition to these basic requirements, there are a few other things to keep in mind when choosing hardware for OPNsense:

• Use a 64-bit CPU.

• Use an SSD for the OPNsense installation drive. This will improve performance and startup times.

• Use a dedicated network interface for the OPNsense WAN port. This will help to isolate OPNsense from the rest of your network and improve security.

• Consider using a more powerful CPU and more memory if you plan on using a lot of features or packages.

What steps are involved in the initial setup of OPNsense?​

Because the installation of OPNsense cannot be adequately described using a single heading, we will provide an overview of the installation process and then redirect you to additional resources that provide detailed instructions.

Here is a step-by-step guide to the initial setup of OPNsense:Prerequisites for OPNsense Installation:

• A computer with an internet connection
• A USB drive to install OPNsense from
• A physical server or virtual machine to install OPNsense on

Basic steps to follow for installing OPNsense are given below:

1. Download the OPNsense ISO image from the official website.
2. Create a bootable USB drive using the ISO image.
3. Boot the server or virtual machine from the bootable USB drive.
4. Select the "Install" option and follow the on-screen instructions.
5. Once the installation is complete, reboot the server or virtual machine.
6. Open a web browser and navigate to the OPNsense web interface at https://opnsense_ip_address:443.
7. Log in to the web interface using the OPNsense default password and username:
   • Username: root
   • Password: opnsense
8. Change the default password immediately.
9. Configure the basic OPNsense settings, such as the hostname, time zone, and network interfaces.
10. Create firewall rules to allow and deny traffic to and from your network.
11. Enable the IDS to detect and block malicious traffic.
12. Configure web content filtering to block access to unwanted websites.
13. Monitor your OPNsense logs for suspicious activity.

What are the key elements of the OPNsense user interface?​

The OPNsense user interface is designed to be easy to use and navigate, even for users with no prior experience. The main elements of the OPNsense user interface are:

• Menubar: The menubar at the top of the screen provides access to all of the OPNsense features.
• Main content area: The main content area in the center of the screen displays the current page or view.
• Quick Navigation: When you configure and manage your network security, quick navigation will assist you in finding OPNsense's web interface parts.

Figure 1. OPNsense User Interface

The OPNsense user interface is highly customizable. Users can change the layout of the screen, the colors of the interface, and even the default language.

Here are some of the critical elements of the OPNsense user interfaces in the menu bar.

• Lobby: The OPNsense Lobby menu is a special menu that provides access to a few basic features, such as the dashboard, license, password, and logout. It is designed to be a quick and easy way to access these features without having to navigate through the main menu system.

• Dashboard: This menu provides a high-level overview of the system status, including information about CPU usage, memory usage, and network traffic.

• Reporting: This menu provides access to tools for generating reports about the OPNsense system and network, such as firewall reports and traffic reports.

• System: This menu provides access to settings for the OPNsense system, such as the hostname, time zone, and networking.

• Interfaces: The Interfaces menu in OPNsense provides access to settings for the network interfaces on your system. You can use this menu to configure the IP addresses, routing, and other settings for your network interfaces.

• Firewall: This menu provides access to settings for the OPNsense firewall, such as rules, NAT, and port forwarding.

• VPN: This menu provides access to settings for the OPNsense VPN server, such as protocols, users, and certificates.

• Services: This menu provides access to settings for various OPNsense services, such as the DHCP server, DNS server, and web server.

• Power: The Power menu in OPNsense provides access to options for shutting down or restarting your system. You can also use this menu to schedule a shutdown or restart.

• Help: This menu provides access to the OPNsense documentation and community forum.

What are Firewall Rules, and Why are They Important?​

Your firewall rules serve as guards, keeping out intruders and preventing damage to your network. You must fully understand the significance of these rules to provide adequate network security:

• The Gatekeepers of Network Security: Imagine your network as a majestic castle, and the firewall rules as the vigilant gatekeepers stationed at the castle's gates. Their role is to determine who can enter and who must be turned away.
• Guidelines for Network Traffic: Firewall rules provide clear guidelines for network traffic. They specify what's allowed and what's blocked, ensuring that only the right connections are permitted. This helps maintain the integrity of your network.
• Defense Against Unwanted Guests: As a means of keeping unwelcome visitors out of your network, firewall rules serve an important purpose.Creating rules to stop unauthorized access will stop bad people from taking advantage of security holes or getting in without permission.
• Thwarting Various Threats: Firewall rules are your first line of defense against a variety of cyber threats. They can thwart denial-of-service attacks, port scanning attempts, and intrusion attacks. With the right rules in place, you can significantly reduce your network's vulnerability.
• Managing Ports and Protocols: Firewall rules offer control over the use of specific ports and protocols. For example, you can block known malware-associated ports or limit access to critical services. This level of control enhances your network's security posture.
• Filtering Traffic for Safety: You can filter traffic based on certain factors, such as content, with these rules. Firewall rules help you get rid of possible threats by blocking dangerous websites or applying limits to certain programs.
• Guard Against Denial-of-Service Attacks: Denial-of-service (DoS) attacks aim to flood your network with traffic, rendering it unavailable. Firewall rules can be configured to detect and mitigate these attacks by limiting incoming traffic rates or blocking suspicious sources.
• Visibility and Control: You can see what is going on in the network thanks to firewall rules, which let you keep an eye on things and figure out what is going on. This information is beneficial for finding strange things and handling possible security problems.
• Compliance and Regulations: Many industries have regulatory requirements for network security. Firewall rules help you align with these standards, such as PCI DSS or HIPAA, by safeguarding sensitive data and demonstrating compliance.

Firewall rules protect your network by enforcing rules and letting only authorized traffic into your digital world. When you carefully write and follow these rules, you strengthen your defenses and are ready to protect your network from all the threats that live in the digital world.

What is Network and Port Forwarding in OPNsense?​

Network forwarding allows you to direct traffic from your computer's Internet connection to another device, such as a server, when someone visits your website. Port forwarding is a type of network forwarding that allows you to redirect traffic from a specific port on one network interface to a specific port on another network interface. For example, if you have a home network with a router and a gaming console, you can configure port forwarding on the router to send traffic on port 80 (which is the port that web servers typically use) to the gaming console. This will allow you to play online games that require port 80 to be open. Network forwarding is the process of routing traffic from one network interface to another.

There are many situations where users might need to configure network and port forwarding. Here are a few examples:

• To host a website or web application
• To run a gaming server
• To use peer-to-peer software
• To access remote devices, such as security cameras or NAS devices
• To use VoIP software, such as Skype or Discord

It is important to follow some best practices when configuring your network and port forwarding to protect your network from potential security risks, including the following:

• Only forward ports that you need to forward

• Use strong passwords for all of your devices.

• Keep your software up to date.

• Use a firewall to filter traffic on your network.

What security features does OPNsense offer to protect a network?​

Keeping your network secure is more crucial than ever in today's interconnected world. You can protect your network from threats and vulnerabilities with OPNsense. It is one of the best multipurpose open-source firewall and routing platforms. OPNsense security features are as follows:

• Stateful Firewall: When it comes to protecting your network from unwanted visitors, OPNsense's stateful firewall is your first and best line of defense. It thoroughly examines all incoming and outgoing data and discards any packets that do not conform to its rules. Firewall rules can be set up quickly and easily, even by those with no prior experience, thanks to the intuitive web interface.
• IDPS (Intrusion Detection and Prevention System): OPNsense's Intrusion Detection and Prevention System (IDPS) is a watchful protector that keeps an eye out for attacks like port scans and DOS attacks in network traffic. This advanced system can detect potential threats and take proactive measures to protect your network, for example, blocking traffic or sending alerts to administrators.
• VPN (Virtual Private Networking): There are several VPN protocols that OPNsense supports, such as IPsec, OpenVPN, and WireGuard. This lets you set up safe tunnels between your devices and the OPNsense firewall. This feature lets you access network resources from afar, keeping your data safe from being hacked or intercepted. Configuration wizards simplify the setup of VPN connections, making it easy to get started.
• Web Content Filtering: OPNsense equips you with powerful web content filtering capabilities, enabling you to block access to malicious and unwanted websites. This feature acts as a shield against malware, phishing attacks, and various online threats. Configuring web content filtering rules is straightforward through the user-friendly web interface. Zenarmor, the most popular OPNsense plugin, uses artificial intelligence (AI)-powered threat intelligence systems to protect users from malicious content on the web.
• 2FA (Two-Factor Authentication): To make security even stronger, OPNsense supports 2FA, which adds another level of security to user accounts. With 2FA, users must enter both their password and a code from their phone to log in. This robust authentication mechanism thwarts unauthorized access, even if passwords are compromised.

OPNsense's popularity stems from the fact that it is designed with the user in mind. With its user-friendly web-based interface, extensive documentation, and community support, users can rest assured that their networks are well protected. With these safeguards in place, you can feel safe knowing your network is protected from today's vulnerabilities and threats.

What is a VPN, and why might beginners want to set up one with OPNsense?​

VPN is an abbreviation for Virtual Private Network. While you use the internet, a VPN operates in the background, keeping you safe and preserving your privacy. It's like having a digital bodyguard on call at all times, whether you're at home, at work, or using public Wi-Fi.

When you use a VPN, all of your data is encrypted from the moment it leaves your device. Your data is sent through a secure intermediate step known as a VPN server. This server can conceal your personal information. It may pretend that you are checking in from somewhere else in the world, allowing you to access geo-restricted services.

OPNsense beginners might want to set up a VPN with OPNsense for several compelling reasons. First and foremost, VPNs enhance security by adding an extra layer of protection to your internet connection. Let's delve into the additional reasons why beginners might opt to set up a VPN with OPNsense:

• VPNs offer an extra layer of protection to your internet connection, making it more difficult for cybercriminals to access the information stored on your device.
• Beginners can use a VPN to encrypt their internet traffic when connecting to public Wi-Fi networks. It secures users by protecting sensitive data from potential surveillance by malicious actors on the same network.
• By hiding your IP address and location, a VPN can help you retain your privacy by making it more difficult for marketers and other third parties to monitor your online behavior.
• A VPN can facilitate the circumvention of content restrictions imposed by geographical boundaries. Users can access websites or streaming services that are inaccessible because their internet service provider may have blocked them by using a VPN.
• Some ISPs (Internet Service Providers) throttle or restrict Internet traffic. VPNs can protect beginner users from bandwidth limitations by ISPs.
• Some internet service providers restrict or slow down certain kinds of online activity. If you're just starting online, a VPN might help you avoid having your connection slowed down by your ISP.
• Setting up a VPN using OPNsense may be an excellent learning experience for newbies interested in networking, security, and system administration.

Configuring a VPN on OPNsense is easy thanks to the use of plugins like OpenVPN, WireGuard, and IPsec. These protocols provide not just strong encryption but also extra safety measures.

OPNsense makes VPN configuration easy for newcomers by providing thorough documentation and tutorials.

What are the best plugins every OPNsense user should have?​

OPNsense offers a wide array of plugins, each designed to enhance the functionality and capabilities of this open-source firewall and routing platform. These plugins cater to various needs, from network security and monitoring to VPN solutions and content filtering.

While the selection of OPNsense plugins depends on specific requirements, certain plugins stand out for their versatility and utility. Whether you're looking to bolster network security, improve performance, or enhance usability, these are the essential OPNsense plugins that every user should consider integrating into their system.

Here's a list of some noteworthy OPNsense plugins that can elevate your network management experience:

1. Zenarmor

2. WireGuard

3. NGINX

4. Rspamd

5. FreeRADIUS

6. OpenVPN

7. Snort

8. Suricata

9. Tailscale

10. HAProxy

1. Zenarmor​

The advanced OPNsense firewall plugin Zenarmor NGFW, created by Zenarmor, offers cutting-edge next-generation features. This all-software instant firewall can be seamlessly deployed virtually anywhere. Zenarmor is currently compatible with OPNsense, FreeBSD, pfSense software, and Ubuntu Linux.

Key features of Zenarmor include:

• Application control: Zenarmor NGFW allows you to control which applications are allowed to access the internet and which resources they can access. This can help to prevent malware and unauthorized access to sensitive data.
• Network analytics: Zenarmor provides real-time network traffic analysis and reporting. This can help you identify and investigate suspicious activity.
• TLS inspection: Zenarmor can inspect encrypted TLS traffic for malware and other threats. This is important because many malware attacks now use TLS encryption to evade detection.
• Web filtering: Zenarmor can be used to block access to malicious and inappropriate websites.
• User filtering: Zenarmor can be used to filter traffic based on user, group, or device.
• Policy-based filtering: Zenarmor can be used to create and enforce policies based on a variety of factors, such as application, user, group, or device.
• Reporting: Zenarmor provides a variety of reports that can help you monitor and analyze your network traffic.

Zenarmor conveniently utilizes the OPNsense package system for hassle-free updates. You can install it through the OPNsense web interface or via SSH or local system access through the command line interface. Once installed, you'll find the Zenarmor menu in the OPNsense web interface's left sidebar.

2. WireGuard​

WireGuard is a VPN (Virtual Private Network) protocol known for its simplicity and speed, harnessing modern cryptographic techniques. This versatile protocol can be configured in two main modes: as a Road Warrior WireGuard setup for remote clients or as a Site-to-Site setup, facilitating the secure connection of two networks. Unlike its counterparts, IPsec and OpenVPN, WireGuard stands out for its commitment to delivering a faster and less complex VPN solution. It is renowned for its ease of configuration, especially on the OPNsense platform, making it an attractive choice for users ranging from individuals at home to small office and business environments.

Some of the Key Features of WireGuard are given below:

• Road Warrior setup for remote clients or Site-to-Site setup for network connections.
• Simple configuration and setup on OPNsense
• Utilizes modern cryptography and network code for encryption.
• Aims for speed, simplicity, and efficiency compared to IPsec and OpenVPN.

The most notable benefits of the WireGuard plugin in Opnsense can be listed as:

• Fast and secure VPN connections with modern cryptography.
• Easy configuration and setup on OPNsense.
• Designed to be faster, simpler, and more efficient than IPsec and OpenVPN.

Here are some use cases for WireGurad VPN:

• Providing fast and secure VPN connections for remote employees.
• Connecting two networks securely.
• Enhancing network security for home, small office, and business users

3. NGINX​

NGINX is a versatile plugin for OPNsense that extends its capabilities in local website hosting, load balancing, reverse proxy, and web application firewall (WAF) functionalities. Some of the key features and use cases of NGINX are given below:

• Local Website Hosting: NGINX enables the hosting of websites directly from OPNsense, though caution is advised due to security considerations. Suitable for technically savvy home users seeking power savings and control
• Load Balancing: NGINX can distribute incoming traffic across a group of servers, with default upstream verification for added reliability.
• Reverse Proxy: NGINX serves as a straightforward reverse proxy solution, incorporating web application firewall and SSL capabilities. It facilitates proxying requests to pre-configured upstream servers.
• Web Application Firewall (WAF): NGINX can function as a WAF through the NAXSI module, enhancing security.

NGINX brings additional functionality to OPNsense, offering users local website hosting, load balancing, reverse proxy, and WAF capabilities. However, it's important to note that certain features may require advanced expertise, making them better suited for experienced users. Installation and configuration guidance for NGINX on OPNsense can be found in the official OPNsense documentation.

4. Rspamd​

Rspamd is an advanced spam filtering and email scanning system that can be integrated with OPNsense, a popular open-source firewall and routing platform. When implemented as a plugin in OPNsense, Rspamd provides powerful email security features.

Key Features and Uses of Rspamd are as follows:

• Spam Filtering: Rspamd specializes in robust spam detection and filtering, helping to keep unwanted and potentially harmful emails out of your inbox.

• Malware Scanning: It can scan emails for malware and malicious attachments, providing an additional layer of protection against cyber threats.

• Custom Policies: Users can configure custom filtering policies and rules to tailor the email security settings to their specific needs.

• Greylisting: Rspamd supports greylisting, a technique that helps reduce spam by temporarily rejecting emails from unknown senders.Rspamd complements OPNsense by bolstering email security. It's particularly useful for organizations and individuals looking to protect their email systems from spam, phishing attempts, and malware.

5. FreeRADIUS​

FreeRADIUS is an open-source, high-performance Remote Authentication Dial-In User Service (RADIUS) server that can be integrated seamlessly with OPNsense. This integration enhances network authentication and security.

Some of the key features and use cases of FreeRADIUS are given below:

• User Authentication: FreeRADIUS is primarily used for authenticating users who connect to a network or services like VPNs, Wi-Fi, and more. It ensures that only authorized users gain access.
• Accounting: It tracks usage data, providing detailed accounting and auditing capabilities, which are crucial for billing and compliance.
• Multi-Protocol Support: FreeRADIUS supports a variety of authentication protocols, including EAP (Extensible Authentication Protocol), PAP (Password Authentication Protocol), and more.
• LDAP Integration: Integration with Lightweight Directory Access Protocol (LDAP) and Active Directory for centralized user management is possible, simplifying administration.

FreeRADIUS enhances OPNsense by providing robust user authentication and accounting capabilities. It's particularly valuable for organizations that require secure user access control to their networks and services.FreeRADIUS is essential for businesses, educational institutions, and organizations of all sizes that need to manage user access and authentication effectively. It's indispensable for secure network access, VPN connections, and Wi-Fi access control.

6. OpenVPN​

OpenVPN is a VPN solution that may be easily integrated with the open-source firewall and routing software OPNsense. Collectively, they constitute a safe and flexible method of establishing distant connections. Some of the key features and use cases of OpenVPN are given below:

• Remote Access: OpenVPN facilitates secure remote access to a network, enabling users to connect to their organization's resources or home network from virtually anywhere.
• Site-to-Site VPN: It supports Site-to-Site VPN connections, allowing different networks (e.g., branch offices) to communicate securely over the internet as if they were on the same local network.
• Strong Encryption: OpenVPN employs robust encryption protocols to protect data transmission, ensuring the confidentiality and integrity of information.
• User Authentication: Users can be required to authenticate themselves before accessing the network, enhancing security.
• Multi-Platform Support: OpenVPN is compatible with various operating systems and devices, making it versatile for both personal and enterprise use.

OpenVPN is a fantastic addition to OPNsense since it allows for safe remote connectivity. It guarantees the greatest levels of security while allowing users to access network resources, collaborate, and work remotely.

OpenVPN on OPNsense is invaluable for businesses, organizations, and individuals who require secure remote access to their networks. It's suitable for remote employees, remote branch offices, or anyone seeking a secure and versatile VPN solution.

7. Snort​

As an Intrusion Prevention System (IPS), Snort can be added to OPNsense as a plugin. Its main function is to quickly find and stop security threats through deep packet inspection. Some of the key features and use cases of Snort are given below

• IPS Capabilities: Snort operates as a robust IPS system, capable of identifying and thwarting security threats effectively.
• Alerts: Users can access alerts generated by the IDS/IPS system in the "Alerts" tab. This provides crucial details about detected events or threats, aiding in rapid response.
• Custom Configurations: OPNsense supports personalized Snort configurations using a specific file format. Users can add custom options by creating a template file.
• Rulesets: Snort allows users to choose from a variety of intrusion detection rules (referred to as rulesets) tailored to monitor or block specific network traffic types. These rulesets can be automatically updated to maintain relevance. Some rulesets are freely available, while others require a subscription.

Snort significantly enhances OPNsense's capabilities by delivering a comprehensive IPS system that identifies and prevents security threats.

Snort is great in many situations. For example, it improves the network security of home users, small businesses, and businesses by monitoring and blocking network traffic well, letting you make your own configurations, and giving you a lot of ruleset options.

8. Suricata​

Suricata is a free and open-source network intrusion detection system (IDS) and intrusion prevention system (IPS). It is a high-performance and scalable solution that can be used to detect and block a wide range of malicious network traffic, including malware, exploits, and denial-of-service attacks.

Suricata is available as a plugin for OPNsense, which makes it easy to set up and manage. To install the Suricata plugin, simply go to the System > Plugins page in the OPNsense web interface and search for "Suricata". Once installed, you can enable and configure Suricata from the Firewall > IDS/IPS page.

Suricata can be used in a variety of ways to protect your OPNsense firewall. For example, you can use Suricata to:

• Detect and block malicious traffic before it reaches your network
• Monitor your network for suspicious activity
• Identify and track known attackers
• Generate reports on security incidents

Suricata is a powerful tool that can help to improve the security of your OPNsense firewall. However, it is important to note that it can be resource-intensive, so it is important to make sure that your hardware is powerful enough to run it effectively.

Here are some of the key features of Suricata:

• High performance and scalability
• Wide range of detection capabilities, including malware, exploits, and denial-of-service attacks
• Flexible configuration options
• Support for a variety of rule sets
• Integration with other security tools, such as firewalls and SIEM systems

9. Tailscale​

Tailscale is a secure, zero-trust, and modern VPN solution that can be seamlessly integrated with OPNsense. This integration enhances network security, accessibility, and management. Some of the key features and use cases of Tailscale are given below:

• Mesh VPN connectivity: Tailscale allows OPNsense to connect to other Tailscale-enabled devices using a mesh VPN topology. This means that devices can communicate with each other directly without the need for a central server. This can improve performance and reliability, and it also makes it easier to set up and manage VPNs.
• Easy to use: Tailscale is designed to be easy to use, even for people with no prior experience with VPNs. Once the Tailscale plugin is installed and configured on your OPNsense firewall, you can simply install the Tailscale client on your devices and connect them to your Tailscale network.
• Secure: Tailscale uses WireGuard, a fast and secure VPN protocol. It also uses end-to-end encryption to protect your data in transit.
• Scalable: Tailscale can scale to support a large number of devices. It is a good choice for organizations of all sizes, from small businesses to large enterprises.

The Tailscale plugin can enhance the capabilities of OPNsense in the following ways:

• Provide easy-to-use VPN connectivity: Tailscale makes it easy to set up and manage VPNs for remote workers, site-to-site VPNs, and other use cases.
• Improve performance and reliability: Tailscale's mesh VPN topology can improve performance and reliability for VPN connections.
• Increase flexibility: Tailscale can be used to create a variety of VPN configurations, such as remote access VPNs, site-to-site VPNs, and mesh VPNs.

10. HAProxy​

HAProxy is a high-performance, open-source load balancer and reverse proxy solution that can be seamlessly integrated with OPNsense. This integration enhances web traffic management, distribution, and security.Some of the key features and use cases of HAProxy are given below

• Load balancing: HAProxy can be used to distribute traffic across multiple servers. This can improve performance and reliability, and it can also help reduce the load on individual servers.
• Reverse proxying: HAProxy can be used as a reverse proxy to direct traffic to specific servers based on the request. This can be used to improve security and performance, and it can also be used to implement complex web applications.
• Content caching: HAProxy can be used to cache content, which can improve performance and reduce bandwidth usage.
• SSL termination: HAProxy can be used to terminate SSL connections, which can improve performance and security.
• Health checking: HAProxy can be used to monitor the health of servers and automatically switch traffic to healthy servers.
• Session persistence: HAProxy can be used to keep users connected to the same server for the duration of their session. This can improve performance and reliability.

HAProxy enhances OPNsense by providing advanced web traffic management capabilities. It ensures that web services remain available, scalable, and secure, making it suitable for organizations of all sizes.