UPnP problem

[Klaus_1250]

I've manually setup µTorrent to listen to port 6350 and forwarded that port on my router. I also enabled to box to use UPnP. (in case something or someone removed the manual port forward).

Until recently, that didn't gave any problem. But today I noticed that µTorrent was saying

UPnP(6352) OK

. It seems the behaviour of µTorrent has changed and it now forwards a port on the router internally to 6350. So when looking in my UPnP-table on the router, I saw µTorrent had added a mapping from external-ip:6351 -> internal-ip:6350 and external-ip:6352 -> internal-ip:6350, next to the already present external-ip:6350 -> internal-ip:6350. Last, but not least, only TCP was mapped, not UDP?

I think this behaviour should be mentioned somewhere. Also, why did µTorrent add both 6351 and 6352? Did it forget to remove the previous mapping when I closed it? And why doesn't it forward UDP? That means DHT won't work with UPnP?

-A PREROUTING -p tcp -m tcp -d xx.xx.xxx.xxx --dport 6351 -j DNAT --to-destination 192.168.1.102:6350
-A PREROUTING -p tcp -m tcp -d xx.xx.xxx.xxx --dport 6350 -j DNAT --to-destination 192.168.1.102:6350
-A PREROUTING -p tcp -m tcp -d xx.xx.xxx.xxx --dport 6352 -j DNAT --to-destination 192.168.1.102:6350
-A FORWARD -p tcp -m tcp -d 192.168.1.102 --dport 6350 -j logaccept
-A FORWARD -p tcp -m tcp -d 192.168.1.102 --dport 6350 -j logaccept
-A FORWARD -p tcp -m tcp -d 192.168.1.102 --dport 6350 -j logaccept

The code that I added through the webinterface for manually portwarding some p2p-traffic:

-A PREROUTING -p tcp -m tcp -d xx.xx.xxx.xxx --dport 6346:6350 -j DNAT --to-destination 192.168.1.102
-A PREROUTING -p udp -m udp -d xx.xx.xxx.xxx --dport 6346:6350 -j DNAT --to-destination 192.168.1.102
-A FORWARD -p tcp -m tcp -d xx.xx.xxx.xxx --dport 6346:6350 -j logaccept
-A FORWARD -p udp -m udp -d xx.xx.xxx.xxx --dport 6346:6350 -j logaccept

[dcorban]

I also noticed that µTorrent had set a different external and internal port. I selected a different port and it hasn't changed again, but I am curious why it suddenly decided to do this.

I know there are several situations where µTorrent will not remove a mapping it has added. The most annoying one is when you simply change the port in the program options. It adds the new port mapping but never removes the old one. Also if the program crashes (which happens too often for my comfort), and you have random port mapping on, you will end up with multiple ports mapped.

[mrb1ue]

I was playing with the UPnP setting in µTorrent (v 1.2.2) today and noticed that it doesn't remove the forwarding port even when µTorrent is gracefully closed. I did not experience the same issue as the previous posts where it was opening a different port externally than internally. Both my internal and external port was the same as it should be. µTorrent just won't delete the forwarding even if the program closes down properly.

[ironboyzz]

Noticed that too (posted in another post)...had to go into "Internet Gateway" (disabled!!!???) and delete utorrent entries there and seemed to clear up problem!!

[Klaus_1250]

Noticed that too (posted in another post)...had to go into "Internet Gateway" (disabled!!!???) and delete utorrent entries there and seemed to clear up problem!!

If people have entered the random port thingy and use UPnP, that could create a problem. I don't understand why Ludde or a mod hasn't anything to say about this.

[mrb1ue]

I've posted this bug at the bug tracking site. So hopefully it will get looked at and addressed.

http://www.utorrent.com/bugs/view.php?id=59

[ironboyzz]

@Klaus_1250 > I can't see why/how any peeps c/would do random port based on port forwarding!!! I personally don't use it. A random range would be awesome!!! I change out my port once a wk usually!

[Klaus_1250]

There's is a checkbox: Randomize port each time µTorrent starts. Just below it is the box t enable UPnP-mapping. So, combining the two should give you a randomly mapped port each time µTorrent starts.

Next to that, reading my toppost again, if you would fill in a port-nr in the box above those 2 checked checkboxes, I think the behaviour would be, to randomly map an exteral port on the router, to the local port defined in the "Port used for incommming connections" box.

Downside is that I haven't seen µTorrent removing UPnP portmappings, so I wouldn't use the random port feature...

[mrb1ue]

Well, this problem appears to be fixed in the latest version I'm running (v1.4.1 Beta build 406), but I couldn't find anything about it in the changelogs. Has anyone else seen or heard anything?

[Firon]

I guess ludde forgot to add it to the changelog, but it has been fixed.

[mrb1ue]

Excellent. Thanks for the update.

[mrb1ue]

This problem appear to have surfaced again in v1.4.1 beta (build 412).

Also, indyhill might have found another issue with the UPnP here:

http://forum.utorrent.com/viewtopic.php?id=5402

I don't use the DHT network very often so I haven't really noticed the error he's alluding to.

[mrb1ue]

This problem has come up again in the latest betas. Can it please be fixed again?

Thanks.

[Aqualung]

Here's my issue with the UPnP feature, although I am not sure if it is relevant to this discussion (apologies if it isn't). Please tell me if this is indeed an issue or a "feature," and if it is indeed an issue, I'd appreciate some help.

Running uTorrent 1.4.1 BETA (build 418). Here's what my Network Options settings look like:

(1) Port used for incoming connections: 50001

(2) Randomize port each time uTorrent starts: clear (don't want it)

(3) Enable UPnP port mapping: yes (note that my router's port 50001 is not explicitly forwarded since I figured that's what UPnP does, right? And yes, my router is UPnP capable, and yes, UPnP is enabled)

How come, now, that the uTorrent status bar shows "UPnP(50002) OK"? Why 50002 and not 50001? Also, to add insult to injury, the tracker reports my status as "stealth firewalled" or "unconnectable."