I have a raspberry pi and multiple hosts that I would like to connect to a VPN in a physical manner, i.e. I would like to be able to plug my devices into one (unmanaged) switch and have them connected through a VPN, and plug devices that I want to access the internet directly into another. I still want the DHCP server on my router to manage IP addresses for every host.
I have tried a few things so far, and have a working openvpn client connection to my VPN provider, which provides tun0. I have a USB network adapter, which is shown as eth1, and would like to send packets from eth1 (connected to switch), to eth0 (connected to router) if it is local & vice versa, and send all packets bound for the internet read on eth1 to tun0.
PI as VPN gateway which routes all requests through a VPN tunnel was helpful but didn't work for me in the end.
https://raspberrytips.com/raspberry-pi-vpn-gateway/ was what i started with, as I believed a wireless access point surely was not dissimilar to what I am trying to achieve, however, the creation of an access point was handled with nmcli at a pretty high level, and I am unable to translate that into using a network interface instead.
My internet connection is not very high bandwidth, doubly so with a VPN, so I am not worried about this process being inefficient.
