I'd like to make this into a full-featured post at some point, but for now I'm just writing down the essentials for getting a working ipv4 openvpn setup to work using ipv6\. There are two steps: 1\. Use IPv6 as the protocol to communicate between client and sever 2\. Use IPv6 addresses for the clients I had particular challenges with this because I'm using Cloud at Cost as my VPN server, and they provide a really small subnet. openvpn assumes you'll have a /64 or /112 netmask, but mine is /120 and I gave /124 to my vpn subnet.