ASUS OpenVPN site-to-site: adding bi-directional routing

[mystical]

Hi,

I have found no useful documentation of the OpenVpn advanced configuration options in the Asus manual, and so I have come here after spending a couple days searching forums without finding a clear description of the solution.

I have two Asus RT-AC68U routers running the same current factory firmware 3.0.0.4.380_1842. I have easily configured them so that the home system with LAN 192.168.130./24 accepts an OpenVpn connections from my remote office with LAN 192.168.131.0/24.

My problem is that machines on 192.168.131.0 can ping and fully access all machines on 192.168.130.0, but machines on 192.168.130.0 cannot ping or otherwise access the router or any other devices on 192.168.131.0. On the ASUS OpenVpn->Server->Advanced page there is a '

Other threads on this forum seemed to solve this problem by configuring OpenVPN using TAP sessions. However there is broadcast and multicast traffic on both LANs that I don't want to clog the WAN connection. Furthermore, I don't want my remote system to depend upon the OpenVpn connection to service DHCP requests.

Thanks

 

[ThePiratkapten]

Hi there!

I had this problem as well but I have found a solution that works for me. I set up both my Asus RT-AC68U routers (with stock firmware) as OpenVpn servers and let them connect to each other. This worked with TUN. I believe the 'client' router doesn't accept connections from the VPN it is connected to, to its local network. The opposite works though, as the 'server' router allows devices on its VPN connect to its local network. Having the two routers as both servers and clients solves the problem with bi-directional routing.

I have only tested this for a short period of time but so far I haven't noticed any routing problems.

 

[mystical]

Hi,

I had not thought of that solution, but in my case one of the routers is behind another router. So opening a VPN connection to that 'hidden' router is more complex than just getting the tunnel opened by the 'hidden' router to be bi-directional.