The best open source alternative to OPNsense is OpenWrt. If that doesn't suit you, our users have ranked more than 10 alternatives to OPNsense and 15 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to OPNsense are pfSense, IPFire, DynFi Firewall and VyOS.
OpenWrt Project is a Linux operating system targeting embedded devices. Instead of trying to create a single, static firmware, OpenWrt provides a fully writable filesystem with package management. This frees you from the application selection and configuration provided by the...
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pfSense is a free and open source firewall and router that also features unified threat management, load balancing, multi WAN, and more.
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IPFire is a server distribution with intended to use as a firewall. It focuses on flexibility, and scales from small to middle sized business networks and home networks.
DynFi® Firewall is the first French Open Source firewall. The system integrates many filtering features and allows for the first time to manage a large number of your appliances. Available for free, DynFi Firewall has two images (with VGA or Serial return) compatible with...
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Endian Firewall Community (EFW) is a "turn-key" linux security distribution that turns every system into a full featured security appliance with Unified Threat Management (UTM) functionality. The software has been designed with "usability in mind" and is very...
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Zeroshell is a Linux distribution for servers and embedded devices aimed at providing the main network services a LAN requires. It is available in the form of Live CD or Compact Flash image and you can configure and administer it using your web browser.
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The SmoothWall Open Source Project was set up to develop and maintain SmoothWall Express - a Free firewall that includes its own security-hardened GNU/Linux operating system and an easy-to-use web interface.
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IPCop Firewall is a Linux firewall distribution geared towards home and SOHO (Small Office/Home Office) users. The IPCop interface is very user-friendly and task-based. IPCop offers the critical functionality of an expensive network appliance using stock, or even obsolete...
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ImmortalWrt is a Linux-based embedded operating system for network devices such as routers and access points. It is a fork of OpenWrt. ImmortalWrt includes additional packages, expanded device support, and optimized default profiles.
BSD Router Project (BSDRP) is an embedded free and open source software router distribution based on FreeBSD with FRRouting (Quagga fork) and Bird.
Zorp GPL is a next generation, open source proxy firewall with deep protocol analysis. It allows you to inspect, control, and modify traffic on the application layer of the ISO/OSI model. Decisions can be made based on data extracted from the application-level traffic (for...
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