Help with port forwarding and docker

[remmina 0]

My setup is as follows. I have a docker setup where i run my vpn server in one container and my transmission application in another container. My transmission container uses the vpn container as a gateway which works quite nice. My only problem is that i'm unable to forward my peer listening port from my airvpn connection to the transmission container. I have added the port forwarding at airvpn.org but dont know how to forward it to my transmission container.

 

I guess I have to add some iptables rules to my vpn gateway, which uses openvpn+iptables to connect airvpn servers.

 

Does anyone have an idea of how to configure iptables to handle port forwarding?

[joshrivers 0]

I'm currently undoing openVpn-in-docker in my setup to simplify this stuff. I'm going to just have a whole VM allocated to locked down vpn traffic and run my transmission/etc inside of that VM.

 

Docker is doing some excruciatingly clever things with IPTables already in order to create network devices, and route traffic around between 'containers' (which are a fiction on top of a lot of low level Kernel capabilities). None of it is magic or incomprehensible, but it can be complex and occasionally buggy. I was happy with dockerized openvpn until I wanted to add flexibility...thats when I decided it was too much effort.

 

If you're still up for learning it (and I'd start with a good iptables tutorial) I'd refer you to https://github.com/haugene/docker-transmission-openvpn which is a openvpn/transmission all-in-one, and this gist https://github.com/sebgl/htpc-download-box which has some direction on sharing network interfaces between containers using network_mode in the container instantiation.

 

Good luck!