Intel N100 Firewall Mini PC: 4-Port 2.5GbE Boxes for OPNsense and pfSense

The appeal is control. OPNsense and pfSense offer stateful firewalling, VLANs, multi-WAN failover, WireGuard and OpenVPN, DNS filtering, traffic shaping and intrusion detection, with updates you schedule yourself.

Four ports is the most common layout, and it maps neatly onto a home network.

• Port 1, WAN: the modem or ONT.
• Port 2, LAN: the main switch and trusted devices.
• Port 3, IoT: cameras, smart plugs and TVs, walled off from the LAN.
• Port 4, guest or lab: visitors, or a homelab segment that can break without taking the house down.

A 2.5GbE port on each leg lets multi-gigabit fibre plans and a 2.5GbE switch run at full speed. Wi-Fi comes from separate access points, which is better practice anyway: the firewall sits in a cupboard, the access points sit where the signal is needed.

Power suits a 24/7 job. The N100 carries a 6W rating from Intel, and most of these boxes run fanless. A whole firewall box typically draws a few watts more than a consumer router, and far less than a repurposed desktop. The N100 idle wattage figures give the detail.

The i226-V uses FreeBSD's built-in igc driver, supported in pfSense 2.7 and current OPNsense releases without extra steps. It is the NIC on the MOGINSOK, CWWK, UDPTCP, Dozlzyp, oaknode and Montvfieto boxes.

Realtek's RTL8125 family is common on cheaper hardware, including the HEIGAOLAPC four-port box. It works well on Linux, OpenWrt and Windows. On FreeBSD it has a weaker record, and OPNsense users typically install a separate Realtek driver plugin to get stable 2.5GbE.

• OPNsense or pfSense: prefer Intel i226-V.
• OpenWrt, iStoreOS, VyOS or Linux: Realtek RTL8125 is fine.
• Proxmox with a virtual firewall: either; Linux drives the NICs.

Driver support beats raw port speed. A box that holds a stable link at 2.5GbE is worth more than a faster one that renegotiates every few hours.

Load rises with inspection. WireGuard and OpenVPN lean on AES-NI and fast cores; WireGuard throughput depends on packet size and tunnel count. Intrusion detection with Suricata or Zenarmor inspects every packet, and large rule sets are where four efficiency cores start to show their limits at multi-gigabit speeds.

Size the box for the job.

1. Memory: 8GB for routing, VPN and DNS filtering; 16GB for IDS with large rule sets or a few Proxmox guests.
2. Storage: a 128GB SSD is plenty for the OS and logs; pick NVMe or SATA over eMMC for write endurance.
3. Install: write the OPNsense or pfSense image to USB, boot from it, assign WAN and LAN by MAC address, then set the rest from the web UI.
4. BIOS: enable auto power-on after power loss, so the network returns after an outage.

Barebones such as the CWWK and Dozlzyp take a DDR5 SO-DIMM and an NVMe SSD you supply. The MOGINSOK box takes DDR5 up to 32GB; its product name notes that current units may ship with the N150, which routes identically with a little more headroom.

To run the firewall as a VM next to Home Assistant or Pi-hole, see Proxmox and homelab duty on an N100.

The limit is lanes. The N100 has nine PCIe 3.0 lanes in total, and four i226-V ports already take four of them. The 82599ES is a PCIe 2.0 x8 controller by design, so on an N100 it almost certainly runs on fewer lanes than it was built for.

• Realistic use: one 10GbE link to a core switch or NAS, with the router doing basic forwarding.
• Unrealistic: two 10GbE ports at line rate with full firewall inspection.
• Good fit: a homelab where the servers sit on 10GbE and the WAN is 1–2.5Gbps.

It ships barebone with no RAM or storage, takes one SO-DIMM up to 32GB (oaknode's text names both DDR4 and DDR5, so confirm the generation before buying a stick), and adds an M.2 NVMe slot plus a SATA port. The SIM tray and mini-PCIe slot enable 4G failover when the main line drops, a feature few home routers offer. The 82599ES is supported by FreeBSD's ix driver, so OPNsense and pfSense see the SFP+ ports natively.

For most homes, six copper ports beat two SFP+ cages. The UDPTCP six-port box puts six i226 ports behind a DDR4 SO-DIMM, a SATA port and an M.2 slot, which covers WAN, LAN and four segments without a switch in between.

That layout, often called router-on-a-stick, carries every internal network over one trunk port to the switch, tagged by VLAN. It works well up to the speed of that one link. With 2.5GbE, the trunk rarely becomes the bottleneck at home.

Several N100 machines have two ports without being firewall appliances.

• OUMAX dual-LAN mini PC: two gigabit ports, 16GB DDR4, dual M.2 slots and a built-in 45W supply.
• MeLE Quieter DL: fanless, two LAN ports, 4GB, suited to OpenWrt or a light VPN gateway.
• HKUXZR NAS board: two Intel i226-V ports on a Mini-ITX board for a combined NAS and router build.
• ZOTAC CI337 Nano: fanless barebone with dual gigabit.

Pick a four-port appliance when you want physical separation, simple cabling or several WAN links for failover. Pick a dual-NIC box when you already own a managed switch, or want the same machine to serve as a desktop or media PC.

Either way, check the NIC chip against the OS you plan to run, and look for Wake-on-LAN, PXE and auto power-on in the BIOS. More on the two-port and fanless options sits in silent N100 boxes and N100 Mini-ITX boards and barebones.