Any idea how to isolate the traffic of a package?

Hey. Openwrt noob here. Might be a simple problem.

My openwrt router has a fast cpu and I want to get torrent downloading up and running.

My isp blocks torrent traffic so I need to run the tracker/torrent connections over a tunnel. Been doing it for years with a tiny windows box.

The tunnel I have set up on the router already. I run some other traffic over it with a "static route". Works well.

How do I run tracker/dht traffic over the tunnel? I'm even fine with running all the torrent traffic over the tunnel, but I can't figure out how to do it. I can't see any options to map the package to another interface.

Even if I have two lan interfaces 192.168.123.1 and 192.168.123.2 and bind transmission to the second the outgoing traffic still has the source 192.168.123.1 which is indistinguishable from all the other kinds of traffic. I'd like it to work with UDP too as most trackers connect over UDP.

Hmm.. any ideas? I could daisychain a second router but it seems like a bad workaround. I have all this cpu power anyway.

Thanks for reading and/or commenting. Appreciate it!

You can probably do this via Policy Based Routing (PBR). See this page