uTorrent apparently connects to self when using NAT

Hi there. I've started doing some network analysis and run uTorrent from a local machine which is behind a firewall and uses NAT.

My local system is 10.11.0.2

The public IP is 216.162.194.13 and is set in Preferences > Other in uTorrent

I use a static port of 11111 and forward 216.162.194.13 port 11111 to 10.11.0.2 port 11111

I noticed this morning that my system repeatedly attempts to make connections from 10.11.0.2 to 216.162.194.13 on port 11111

I can only assume that since my public IP 216.162.194.13 is shown on the tracker that uTorrent attempts to connect to it, which is nonsensical... there's no point for the client to connect to itself, and it's also a configuration the firewall is unhappy i.e. a local system asking for something to be routed to the external IP address.

I'd think the fix would be quite simple, just ignore both the local IP address and if specified in Preferences > Other the public IP as well.

-- Bob

This isn't a bug, and you'll find other clients do the same. There isn't any problem with it happening either. BT clients don't consider you to be the same by IP and port, they connect, get your peer/client ID, and then consider you the same.

OK, thanks for the clarification.

I ended up adding a rule to the firewall config so that if my local machine tries to connect to the external IP with the BT port that it's allowed. It looks like that's made the firewall happy, and uTorrent isn't complaining about anything, so presumably it's all good.

You don't actually need to really, it doesn't affect performance at all.

I wasn't worried about performance, I was just tired of my firewall telling me that it was rejecting packets because they were routed in stupid ways...