Published: 16 December 2022
Reference: https://docs.opnsense.org/manual/how-tos/wireguard-selective-routing.html
Goal: Set up one or more Wireguard connections from ProtonVPN on OPNsense, with policy based routing, and optional Killswitch.
I'm writing this guide first as a reference for my future self for when I inevitably forget how to do this, but also to help others out. I found there were not many guides on this specific configuration, particularly not with multiple concurrent connections, and these were some steps which were not at all obvious. I did begin with the guide in the official OPNsense documentation, but even that was missing info to make ProtonVPN work. If you are a pfSense user, it is very similar to OPNsense, and you should be able to follow along with some success, but I have not tested it myself.