44Net Connect Routed Subnet: Raspberry Pi

Prerequisites

Set up a single-device tunnel to your Raspberry Pi. Note the IP and name of your WireGuard interface. The name of your WireGuard interface is the same as the name of your config file. For example, if your config file is /etc/wireguard/wg0.conf, then your interface name is wg0. The IP of your WireGuard interface can be obtained from running ifconfig <interface> and finding the IP listed under the interface in the inet field.

This is what the output of ifconfig wg0 looks like.

wg0: flags=209<UP,POINTOPOINT,RUNNING,NOARP>  mtu 1380
    inet 44.27.133.190  netmask 255.255.255.255  destination 44.27.133.190
    inet6 fe80::f728:a0b0:3af5:b5c6  prefixlen 128  scopeid 0x20<link>
    unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 1000  (UNSPEC)
    RX packets 17331  bytes 5865364 (5.5 MiB)
    RX errors 0  dropped 0  overruns 0  frame 0
    TX packets 13389  bytes 2146828 (2.0 MiB)
    TX errors 0  dropped 1 overruns 0  carrier 0  collisions 0

Optional: Setting Up An Access Point

The recommended way to use a Raspberry Pi as the router for your subnet is with two ethernet interfaces. The second can be provided by a USB ethernet adapter or an ethernet hat. However, if you have wireless only clients or wish not to purchase additional hardware, the Raspberry Pi's WiFi interface can be configured as an access point.

Step 1: Set your wireless regulatory domain

Different countries have different rules about which frequencies and bandwidths devices are allowed to use for WiFi. Setting the regulatory domain ensures that your Pi will use the right ones, making it work best with nearby devices and ensuring regulatory compliance.

The Raspberry Pi OS imager asks you to set the wireless regulatory domain during setup, but does not require it. If you didn't set the regulatory domain in the imager configuration, set it now by running sudo raspi-config and going to Localisation Options > WLAN Country. Select your country, confirm, and exit. If you're not sure whether you set the wireless regulatory domain, run the command iw reg get. Look at the country set under global. If it says unset, you have not set the regulatory domain.