Firewall Guides: pfSense, OPNsense, OpenWrt, VPNs, VLANs, and Firewall Rules

Choosing a firewall platform can get confusing quickly because pfSense, OPNsense, OpenWrt, UniFi, and even Synology Router Manager can all technically route traffic, run firewall rules, and handle VPNs. The better question is not “which firewall is best?” It’s which one makes the most sense for the network you’re actually building.

I’ve used pfSense, OPNsense, OpenWrt, UniFi, and other firewall/router platforms in my own home lab and while helping others with home and small-business networks. They can all work well, but they are not all trying to solve the same problem.

If you want the most control, pfSense and OPNsense are usually where I’d start. If you want to replace firmware on a compatible consumer router, OpenWrt makes more sense. If you want the easiest full-network ecosystem, UniFi is usually easier to manage day to day, even if it is not as customizable as pfSense or OPNsense.

This page is the starting point for all of my firewall guides. If you’re brand new, start with the comparison guides below. If you already know which platform you want to use, jump into the pfSense, OPNsense, OpenWrt, VPN, VLAN, port forwarding, or firewall rule sections.

Firewall guides and comparisons for pfSense, OPNsense, OpenWrt, VPNs, VLANs, and firewall rules — *pfSense, OPNsense, and OpenWrt are all powerful, but the right choice depends on whether you want maximum control, easier management, or support for existing router hardware.*

New to Firewalls? Start Here

If you’re building a firewall or router for the first time, I would not start by copying someone else’s VLANs, firewall rules, VPN settings, or port forwards. Get the basic routing setup working first, then add features one at a time.

This is the order I’d follow:

Decide which platform makes the most sense: pfSense, OPNsense, OpenWrt, UniFi, or something else.
Install the firewall on hardware that is appropriate for your internet speed and network size.
Get the WAN and LAN working reliably before changing advanced settings.
Update the firewall and configure basic system settings.
Configure DNS, DHCP, and basic firewall rules.
Add VLANs only if you have a reason to separate devices.
Set up VPN access before exposing services with port forwarding.
Back up the configuration before making major changes.

The biggest mistake people make is trying to build the “perfect” firewall immediately. VLANs, VPNs, IDS/IPS, DMZs, multi-WAN, and advanced firewall rules are useful, but they add complexity. Start with a stable router first, then build on top of it.

Which Firewall Platform Should You Use?

If you’re still deciding between platforms, start with these comparisons:

My general recommendation is simple:

Use pfSense if you want a mature, powerful firewall platform with tons of documentation and a long track record.
Use OPNsense if you want something similar to pfSense, but with a more modern interface and a different update/plugin approach.
Use OpenWrt if you want to replace the firmware on supported router hardware or build a lightweight router on lower-power hardware.
Use UniFi if you want the easiest full-network ecosystem with gateway, switches, access points, VLANs, VPNs, cameras, and remote management in one place.

There is no single best answer for everyone. pfSense and OPNsense are better if you want firewall control. OpenWrt is great for supported router hardware. UniFi is better if you want simplicity and ecosystem management.

pfSense Guides

pfSense is one of the most popular firewall/router platforms for home labs, prosumers, and small businesses. I used pfSense in my own home lab for years, and it is still one of the best options if you want deep control over firewall rules, VLANs, VPNs, routing, packages, and advanced network features.

The main tradeoff is that pfSense can be overwhelming if you are new. It gives you a lot of control, but that also means you have to understand what you’re changing.

Getting Started with pfSense

If you’re new to pfSense, start here:

If you are virtualizing pfSense in Proxmox, make sure you have a recovery plan. Virtualized firewalls can work extremely well, but if your Proxmox host is down or misconfigured, your internet may be down too.

pfSense VPNs, VLANs, Firewall Rules, and Advanced Features

Once pfSense is installed and stable, these are the features most people move into next:

The part where people usually get confused with pfSense is firewall rules. Rules are evaluated on the interface where traffic enters pfSense. So if IoT devices should not access your LAN, the rule belongs on the IoT interface, not the LAN interface.

When I Would Use pfSense

I’d use pfSense if I wanted maximum firewall flexibility, advanced routing, packages, VPN control, VLANs, multi-WAN, or a more traditional firewall-first platform. It’s also a great option if you want to learn networking at a deeper level.

I would not choose pfSense if the main goal is “make this as easy as possible.” It is powerful, but it expects you to understand what you’re configuring.

pfSense Community Resources

OPNsense Guides

OPNsense is very similar to pfSense in terms of what it is trying to do: give you a powerful open-source firewall/router platform with VLANs, VPNs, firewall rules, routing, packages, and advanced security features.

The reason a lot of people look at OPNsense is the interface and update model. It feels a little more modern, and some people find it easier to work with than pfSense. I still think both are strong options, and the better choice depends on what you prefer.

Getting Started with OPNsense

How to Set Up DDNS on OPNsense
How to Install OPNsense in Proxmox (virtualized)

OPNsense VPNs, VLANs, and Port Forwarding

If you’re choosing between pfSense and OPNsense, I would not overthink it too much. Both can run a very capable home or small-business network. The more important thing is understanding firewall rules, backups, VLAN design, and remote access before you start layering on advanced features.

When I Would Use OPNsense

I’d use OPNsense if you want a powerful open-source firewall but prefer its interface, update cadence, plugin system, or general direction compared to pfSense. It is especially appealing if you want something firewall-focused but a little less intimidating at first glance.

OPNsense Community Resources

OpenWrt Guides

OpenWrt is different from pfSense and OPNsense. It is usually used as replacement firmware for supported routers or as a lightweight router operating system on compatible hardware.

I would look at OpenWrt if you want more control over router hardware you already own, or if you want a lightweight firewall/router platform that runs well on lower-power devices. I would not usually pick OpenWrt over pfSense or OPNsense for a larger home lab firewall unless there is a specific reason.

When I Would Use OpenWrt

I’d use OpenWrt if I had supported router hardware and wanted more control than the stock firmware gives me. It is also a good fit for lightweight routing, travel routers, secondary routers, or more advanced configurations on consumer-style hardware.

I would not choose OpenWrt just because it is “more advanced.” If your goal is to build a full firewall appliance with deeper firewall features, pfSense or OPNsense usually makes more sense.

Other Firewall and Router Resources

Not every network needs pfSense, OPNsense, or OpenWrt. Sometimes you are working with VPN design, Synology Router Manager, or deciding how remote access should work.

For VPNs, the split-tunnel vs full-tunnel decision matters. A split-tunnel VPN only sends specific traffic through the VPN, while a full-tunnel VPN sends all traffic through it. Neither is universally better. It depends on whether you want access to internal resources only or want all client traffic routed through your home or business network.

What I Would Avoid as a Firewall Beginner

If you’re new to firewall platforms like pfSense, OPNsense, or OpenWrt, I would keep the first version of your setup simple. You can always make it more advanced later.

Do not virtualize your only firewall without a recovery plan. It can work very well, but if the host goes down, your internet may go down with it.
Do not create VLANs before you understand what should be allowed or blocked. VLANs are useful, but they need firewall rules to actually provide isolation.
Do not copy firewall rules blindly. Rules depend on your network, interfaces, aliases, and traffic direction.
Do not expose services with port forwarding unless you need to. A VPN, Tailscale, WireGuard, or reverse proxy may be a better option.
Do not skip configuration backups. A firewall config backup can save you from rebuilding everything manually.
Do not update blindly on critical networks. Updates matter, but have a backup and a rollback plan before upgrading a production firewall.
Do not assume IDS/IPS is required for every network. It can be useful, but it also adds complexity and can create false positives or performance issues.

The best firewall setups are usually boring in the right ways: stable hardware, clear interfaces, simple VLANs, understandable firewall rules, secure VPN access, regular backups, and updates that are done intentionally.

Final Thoughts

pfSense, OPNsense, and OpenWrt can all be good firewall/router platforms, but they are best for different types of networks. pfSense and OPNsense are the stronger firewall-first platforms. OpenWrt is great for supported router hardware and lightweight routing. UniFi is easier if you want the full ecosystem managed from one place.

If you’re brand new, start with the comparison guides first: pfSense vs OPNsense, pfSense vs OpenWrt, and pfSense Plus vs CE. Once you know which platform makes sense, install it, get the basic WAN/LAN setup stable, back up the configuration, and then start adding VLANs, VPNs, firewall rules, and advanced features one step at a time.