I spend multiple hours fighting the bad fight.

The problem:

Since WSL2 the host network is no longer shared between the host and WSL through a separate network adapter. Great for security and bad for funnelling your traffic through your host's VPN. And for this use case is no straight way to go.

Like every good company, my current client keeps a wire guard VPN to manage secure outside connections and secure the network for remote work.

As a web developer on Windows of course need WSL it is just not sane to fight with the powershell and binary hell for Windows for all the different possible stacks.

My solution was:

1. Share the VPN Connection with WSL:

   You have to change the network settings on your Windows machine to allow the WSL instance to share the VPN connection. Here's how you do it:

   • Open Control Panel -> Network and Internet -> Network and Sharing Center -> Change adapter settings.

   • Right-click on the WireGuard Tunnel adapter, and click on Properties.

   • Go to the Sharing tab and check the Allow other network users to connect through this computer's Internet connection box.

   • In the dropdown menu, select the adapter that corresponds to the WSL instance. It might be labelled as vEthernet (WSL) or vEthernet (Default Switch) or similar. Click OK.

2. Confirm Connectivity Inside WSL:

   Open your WSL instance and check if you can connect through the VPN by running commands such as ping, curl, or wget to confirm you're connecting through the VPN.

This worked for ping, dig and co but ssh and git was still not usable.

This Holly-Comment fixed at least the traffic flow fully with this command in your PowerShell as Admin.

New-NetFirewallRule -DisplayName "WSL" -Direction Inbound  -InterfaceAlias "vEthernet (WSL)"  -Action Allow

Afterwards, I also increased the MTU (Maximum Transmission Unit) as recommended. Without this change ssh and git still was hanging on execution.

sudo ifconfig eth0 mtu 1350

For other souls visiting this circle of windows hell, they can try their hand on

https://github.com/sakai135/wsl-vpnkit

And for the masochist troubleshooting with Microsoft:

https://learn.microsoft.com/en-us/windows/wsl/troubleshooting#wsl-has-no-network-connectivity-once-connected-to-a-vpn

I like my daily dose of pain like any other developer but for today I did not have the nerve and endurance for it anymore.