Can't for my life open port 51413 for Transmission

[raven-au]

The router Web UI is only for port forwarding through WAN. I am not really sure how I would go about such a solution in IPTABLES .

What I'm thinking there is there is an interface on the router from which VPN packets "appear" from incoming connections
and that interface has a known ip address, and is persistent, and is local.

But I don't know how packets get routed to the bridge interface though and I wonder if that routing is setup by the VPN client starting up, it looks like there's only routing for outgoing traffic.

It may also be needed to add filter rules to match packets coming in and going out of that local VPN interface for those apparently non-existent routes to do what's needed.

 

[raven-au]

It only makes sense to use the VPN for remote access purposes if you can be assured the replies will be routed back out the same network interface. If you don't, you face the problem of RPF (reverse path filtering), which thanks to the stateful firewall, will *block* any attempt to route any given connection in from one network interface and out another. IOW, as long as the target of remote access in this case is also bound to the OpenVPN client for outbound purposes, it will work. If not, yeah, you have a problem. The same problem that would occur if that same target was remotely accessed over the WAN while bound to the OpenVPN client.

Yep, and that's why I use a VPN client on the device I run the client myself and tell it the listen IP address and set the interface for external trafic to the VPN interface.

And that works fine without any messing around, no surprises there,