Turn your Pi into a pretty okay-ish travel router (or a very slow main router)!
OpenWrt officially supports Raspberry Pi hardware if you want to run it as your primary OS. But running in a container brings many advantages, one of which is not having to re-flash your SD card if you already have some services running.
Pre-built images are available on Docker Hub. These images have been tested on a Zero W and Pi 4 running Raspberry Pi OS, but should work for other versions too. Refer to the table below (and the notes in openwrt.conf) to choose the right image for your hardware.
Set the IMAGE and TAG variables in openwrt.conf accordingly, replacing <version> with the desired release version (e.g. "19.07.5") or "snapshot" for the latest development snapshot:
| RPi version | image:tag |
|---|---|
| Pi A / B / B+ / Zero W | oofnik/openwrt:<version>-bcm2708 |
| Pi 2 / 3 / 4 (32-bit OS) | oofnik/openwrt:<version>-armvirt-32 |
| Pi 3 / 4 (64-bit OS) | oofnik/openwrt:<version>-armvirt-64 |
You can build the OpenWrt Docker image yourself on the Pi, or on your x86 PC with qemu-user and binfmt-support installed. The image will be built according to the parameters OPENWRT_SOURCE_VER, ARCH, IMAGE and TAG (see openwrt.conf for documentation). Packages fakeroot and squashfs-tools must be installed.
$ make buildIf you built the image on your PC, send it to your Raspberry Pi over SSH:
$ docker save $IMAGE:$TAG | ssh <your_raspberry_pi_host> docker load
By default Raspberry Pi OS does not load the kernel module for IPv6 iptables on boot.
Run sudo modprobe ip6_tables to load it immediately.
To persist on reboot, run
$ echo 'ip6_tables' | sudo tee /etc/modules-load.d/ip6-tables.conf
Raspberry Pi OS ships with a default dhcpcd configuration that assigns a DHCP address to every new interface added to the system including virtual ones.
This is not necessarily what we want. Instead we would like to limit the interfaces dhcpcd watches to only the physical ones, i.e., interfaces eth* and wl*:
$ echo 'allowinterfaces eth* wl*' | sudo tee -a /etc/dhcpcd.conf
$ sudo dhcpcd -n