This is a VERY messy guide outlining my struggles to get raspberry pi zero W USB Ethernet/RNDIS Gadget working on Windows with a shared internet connection.
## TL;DR:
- Download the ACER RNDIS driver
- Add the drivers to the boot
- Set a static IP address and set this in your host operating system's network manager
- When sharing network, add some stuff to the `/etc/network/interfaces` file and most importantly NEVER USE WSL in NAT networking mode (Use `bridged` on windows 11 or the undocumented `virtioproxy` on windows 10) to connect to the pi since wsl has issues with internet connection sharing (ICS) on windows.
## RPI shows up as USB COM port/Serial device in device manager
Right click the device > update driver > browse my computer for drivers
Select the folder containing the **unzipped** [ACER RNDIS driver](https://www.catalog.update.microsoft.com/Search.aspx?q=usb%5Cvid_0525%26pid_a4a2). You may use 7-zip to unzip catalog files.
Download the driver [here](https://www.catalog.update.microsoft.com/Search.aspx?q=usb%5Cvid_0525%26pid_a4a2)
Then the device should show up as an RNDIS Gadget device instead of the serial device.
Reload the `g_ether` module (see next part)
## Tip: command to re-enumerate the device without unplugging and replugging
This unloads and reloads the `g_ether` driver which makes the gadget renumerate (at least on windows).
You'll need to go through the steps of setting the static IP address
Follow this [adafruit tutorial](https://learn.adafruit.com/turning-your-raspberry-pi-zero-into-a-usb-gadget/ethernet-gadget)
TLDR of the adafruit tutorial:
1. Add this to the end of `/etc/dhcpcd.conf` (Avoid changing `/etc/network/interfaces` which is old)
(Change the address/gateway as required)
```
interface usb0
static ip_address=192.168.0.15/24
static routers=192.168.0.1
static domain_name_servers=1.1.1.1
```
2. Reload `g_ether` module as described earlier
3. Follow steps in the adafruit tutorial to configure the network in network and sharing center.
Right click RNDIS network adapter in network and sharing center > properties > select Internet Protocol Version 4 (TCP/IPv4) > properties
Set to "use the following ip address" and put the gateway address (`192.168.7.1`) for **BOTH IP address AND default gateway**, use a mask of 255.255.255.0
## SSH
SSH to the address (in this example 192.168.7.**2**, NOT the gateway address 192.168.7.**1**)
```bash
ssh pi@192.168.7.2
```
## Share your network adapter
Without sharing having the usb ethernet gadget connected seems to disconnect the pi from the internet, even if the wifi is enabled.
Not sure if this is required since I tested this after I caught the WSL error (see below), but I added the following lines `/etc/network/interfaces` as per the adafruit guide:
```
auto lo usb0
iface lo inet loopback
iface eth0 inet manual
allow-hotplug wlan0
iface wlan0 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
allow-hotplug wlan1
iface wlan1 inet manual
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
allow-hotplug usb0
iface usb0 inet manual
```
You need to share your main network adapter, for example a wifi card with the ethernet gadget adapter. Double-click your main adapter (ethernet or wifi card for example) > properties > sharing
Check "Allow other network users to connect ..." then select the adapter for the raspberry pi. You do not need to check the box allowing the adapter to take control of the host adapter.
Press OK and confirm.
⚠ Note that I changed the PI's IP address to match the local network (192.168.137.1). If you need to change the IP address you will get a dialog box when you confirm network sharing. For example, I got a dialog stating an IP address of 192.168.137.1, so change the PI's IP address to something like 192.168.137.135. Don't forget to update the static IPs.
DO NOT USE WSL to connect to the device in NAT mode, internet connection sharing (ICS) seems to break WSL networking resulting in any attempts to ping devices on the network failing (example errors for searchability)
EDIT 2024-07-28: It appears that the NAT networking mode specifically causes this issue, you may try bridged networking mode in windows 11 (I am using windows 10 so I cannot test this) or the undocumented virtioproxy mode in windows 10.
Add this to your `wsl.conf` or `.wslconfig` file and restart wsl:
Note that the `virtioproxy` mode does appear to slow networking down, for example when I run a GUI X program such as `cool-retro-term` over the network to xming on the windows host side, the performance is heavily degraded when using `virtioproxy`.
I originally used debian bookworm lite as my OS, but looks like there are still a lot of issues specifically with the ethernet gadget and I never got it to work (In my case, while I could ping the pi I could never ssh into it, it appeared that the packets were never being recevied by the pi according to the `sshd` logs).
In the end I just switched to bullseye and everything worked fine.
## Other notes
- I ran this command `sudo systemctl enable getty@ttyGS0.service` in desperation on the bullseye OS installation, but I'm not sure if this is required for SSH access. This was from a random section in the [USB ethernet guide](https://forums.raspberrypi.com/viewtopic.php?t=306121) and appears to be for enabling the `screen` command to work properly, so probably not necessary for SSH.
