How to Run Both IPv6 and IPv4 Service on a SINGLE VPS?

[antinucleon]

I have set up OpenVPN 2.3 successfully on a Linode VPS, and I can access website via OpenVPN by IPv4 OR IPv6. Indeed, for some reason, I can only use IPv6 in my company, but the who I share the VPN can only use IPv4. How can I let both service run at the same time?

ps. I tried add both protocal (udp, udp6) in the server.conf, then failed to access the server.

Thanks for viewing or advising. Bow