Split traffic to VPN/WAN from NAS with Docker

[Cadillac5118]

Dear all,

I have the following set-up: A Synology NAS with two lan interfaces of which I currently use one. The NAS is connected to my OPNsense which based on policy based routing is sending the NAS and some other hosts traffic to VPN other hosts go to WAN.

I installed some Docker Container on my NAS and some are required to go via VPN and some need to go to WAN. I was wondering what the smartest way is to achieve that. I would like to avoid to have the NAS connect to my VPN via a Docker container. I was thinking about the following solutions:

1) Split Traffic on NAS and send via LAN interface 1 the VPN traffic and LAN interface 2 for WAN. During my research I did not find anyone describing how to split traffic on the NAS. It also might create problems for the Docker containers as they need to talk to each other.
2) The docker container support connecting to a socks5 proxy. Could I configure it on OPNSense to send the traffic via WAN or VPN? Any pointers besides the manual on how to do it? Could that work?
3) The docker containers connect to specific URL(s) so maybe I could set that up in policy based routing. However, this would be a higher maintenance solution as I would need to keep the URL list current. I am not sure how to identify the correct URL(s) in OPNsense.

Any other ideas on how to get this done? Would appreciate any pointers this keep me busy for a while and I struggle to see the light of day.

Thanks a bunch