If you’re intrigued by the prospect of building a DIY router, Seeed Studio has a board waiting to put a Raspberry Pi Computing Module 4 (CM4) to work. Assuming of course you can find the Pi module.
Seeed’s CM4 router board adds two full-speed gigabit network ports, two USB 2.0 ports, a microSD slot, an HDMI output, a GPIO interface for Raspberry Pi HAT add-ons, and a 0.91-inch OLED screen to your Pi CM4. With the CM4 at the core of the system, you have 32 different options for RAM, storage and wireless capabilities on your homebrew router. The router board comes with OpenWRT installed, but it can run Ubuntu, Raspberry OS, or any other Pi-friendly system.
Seeed notes that in addition to DIY routers, the CM4 router board can also become a gateway, mini-NAS, wireless network bridge, or mini-server. You can buy a Pi CM4 with wireless capabilities, but you’ll probably need (or rather) a separate Wi-Fi setup connected to your DIY router.
Why not just plug a USB to Ethernet adapter into the Pi you already have? Seeed says his board’s RTL8111E controller chip offers “better performance, lower CPU usage, and higher stability for long-term work.” [sic] compared to a USB network card.”
The CM4 router board should be available soon for about $55 from both Seeed and Mouser Electronics, although the latter cites an 11-week turnaround beyond original stock.
Those in the market for a Raspberry Pi CM4 board should consider the advice of Ars commentator MightyPez to keep an eye out for the Pi stock monitor Rpilocator, which offers RSS feeds. You can even set up push notifications with Rpilocator’s official Python script.
