Ac87U as mini vpn server?

[oversim]

Hi, sorry for the strange question.. I have an Ac87U merlin firmware router, but I cannot use it as router (voip, my ftth provider already provided me an AVM device, etc..).
I would like to use it as openvpn "mini server", I'm trying several configs, but without getting it.
I tried to set it as "AP", but VPN options in menù disappeared: they're available only in "Router Mode".
Can I connect a cable lan to one the LAN port, set a fixed IP, and then configure OpenVPN Server daemon in this scenario?

 

[CaptainSTX]

You will need to double NAT your AC87 behind your second router which means a cable from a LAN port on your network facing router to the WAN port on your AC87.

Previously this would have made it difficult or impossible to run a VPN server on the AC87 but with the latest version of Merlin it is possible.

All you have to do is on your first Internet facing router is set up a port forward (VPN Server 1 = 1194 or VPN Server 2 = 1195 ) to the WAN IP assigned to your AC87 by your first router. This will be a private IP but with the forwarding you should be able to connect to your server.

I haven't thoroughly tested it but it worked for me but at least it will get you started.