Jump to content

Router getting clogged


Recommended Posts


I wonder how is the timeout value for the connections uTorrent does to my router set? I just paid a visit to my ISP in aim to figure out why I have connection problems through my router when I use uTorrent, as this morning it was specially bad. It turned out that the table for allowed parralell connections was full, and that mean 2048 connections! then the router simply drop packages.

I am not sure if it's uTorrent that is the bandit here, but it all have started at the moment I started to use uTorrent 1.7Beta. Before that I used both Aurelius and BitTorrent without this problem so somehow it ought to be connected with uT.

So the conclution that was arrived to is that timeout values for connections done my client on my side is set far too high or not initiaated properly, so my router gets filled up with stale unused connections waiting to timeout. The only way out is to reboot the router.

If anyone has some input in this I am gratefull, I have uT set to 100 total connections maximum and 50 maximum per torrent. 8 halfopen, 100 for upspeed (400/200 connection). anyting else of importance?

Link to comment
Share on other sites

If your router is (stupidly) counting UDP packets as connections, it could explain the connection clogging.

uTorrent uses the default timeouts of your operating system, so if your router isn't clearing its tables properly, the problem is either in the router (since some routers track connections for days to weeks by default) or your operating system settings.

More commonly, the router is at fault.

Link to comment
Share on other sites

Hmm I am pretty sure I posted this in the 1.7 Beta threed, would have been nice with a message about the post being moved to a new topic here :-) Thanks for answering anyway.

I posted there as I have reasons to believe there is an issue with the Beta, how come otherwise this just happens when using the uT Beta and not other clients?

I don't manage the router myself, my ISP does, I can only reset it by pulling the plug and put it in again. I will ask them about details tomorrow as they are closed now, but I don't really agree with your reasoning above. Case is there is a limit of the amount of simultaneous parallel connections (2048) the router serves, obvious to limit a DOS etc. and it doesn't make sense UDP connections would pass uncounted.

If the router had done the same thing with any torrent client, I could agree with you the fault is with the router. I am not quite sure what happened as when I came in the morning the computer was put to sleep and refused to wake up again unless manual reset to reboot it. This have happened once before when I have left uT-1.7Beta running overnight (earlier build though), I guess something had crashed, most likely uT (it's reasonable to believe as it's Beta, isn't it? :-), but possibly also my Firewall.

I have found in the advanced settings, peer.disconnect_inactive (true) and peer.disconnect_inactive_interval (300) which I don't know but belive may have something to do with how long uT hang on to a connection? Appearently 300 is a mini value as anything less is ignored (according to online FAQ), that's 5 minute which seem a bit long to me... but what must have happened is that uT have opened more, much more, then the 100 connections I globally have limited it to do, which I belive may happens if something, but not all of uT crashes and it then just opens and hangs on to connections but never disconnect them.

Well I am a bit at loss here, now router is rebooted and uT seem to run fine and so far doesn't open overly many more then the 100 connections set as max. Well that is, the UI shows 100 conns all together, but when I look at my firewall it does hang on to more then this 100, although this possibly is normal. From my short time observing it seem though this slowly slowly increases and I will keep an ey on it and also change so the monitor doesn't go to sleep.

Link to comment
Share on other sites

In case you haven't noticed...µTorrent isn't just "any" file-sharing program.

I'd like to think it is both better and more extreme than almost anything else currently in large-scale use.

Minimize µTorrent's use of UDP packets and the problem will probably reduce.

You can also try lower half open connection rates as well as lower max connections. These too should at least increase the amount of usable time your router has before resets.

Lastly, are you firewalled in µTorrent?

And do you use UPnP?

UPnP uses router's ram as well as its other system resources to maintain a forwarded port to your computer. At least in that regard, it is more ram-consuming than a manual+fixed port forward.

Link to comment
Share on other sites

and it doesn't make sense UDP connections would pass uncounted.

UDP is connectionless. It makes no sense to track UDP packets as connections because of this.

The timeouts you've found are for established connections, not the connection types that are jamming your router. The timeouts on the connection types that are jamming your router are controlled by your operating system and the operating system of the router.

Link to comment
Share on other sites

Switeck: I know it's the best, that's why I have ended up using it :-) I don't have complains about uT, I just notice a problem and is trying to understand why it happens, and one of my observations was it happens with uT but not with other clients.

How can I reduce UDP traffic? I don't know if it has anything to do with it, but sometimes torrents have several trackers in its announce list and there use to be 1 UDP tracker. I have tried to edit such a torrent as uT doesn't support it, but when I do so uT starts to complain the wildest.

Well my connection scenario is this. I sit behind an XP with 2 MB RAM, it connects to a 4 port switch for my LAN and the switch connects to my router. The router is a disc less Linux, it just boot from a floppy and only uses a RAM disc. The router comes from my ISP and is placed under my roof, on the roof I have an antenna which connects to the base access point. I don't have access to login to my router, probably because it throttles my speed (4 Mb down/2 Mb Up), I can just reboot it by polling the power plug.

On my XP I also run an Outpost Firewall and it should be properly set up, at least for uT but sure I cannot exclude it's a part of the problem. I just installed the Firewall because I opened 3 incoming ports in my router, 1 I use for uT and the other 2 I use for dedicated traffic from my collocated online server, where I have my domains.

DreadWingKnight: I spoke with the technician at my ISP and he said the router does not control these timeouts, they are set by the peer opening the connection. uT and the router has run now for several hours w/o problems, with a max dl of 368kb/s and constant 100Kb/s up. It seem this happens just at some point when something on my computer goes wrong, affecting the way connections are opened and closed. Exactly what this is I don't know now, if it's something with uT, my Firewall or possibly PeerGuardian that crashes. Problem is I have had my monitor to switch off after 20 min. inactivity and these things has always happened during the night and I have never been able to wake the monitor again to visually see what has happened. I have changed that now so next time I can hopefully get more leads.

both: thanks for your answers.

Link to comment
Share on other sites

I spoke with the technician at my ISP and he said the router does not control these timeouts, they are set by the peer opening the connection.

I don't believe that, having dealt with the problems being in my router or operating system many times before.

The problems come from the closing connections, whose timeouts are controlled by the TCP stacks of the operating system of either the computer or the router (whichever's timeout is longer).

I'm not saying these things as theory, I'm saying these things from first hand experience.

Reference Linux kernel file net/ipv4/netfilter/ip_conntrack_proto_tcp.c for an example of operating system level timeout settings.

Link to comment
Share on other sites

DreadWingKnight: I have no reason to NOT believe you, and my goal is just to find what and were the problem is triggered. At least I have now got it confirmed it is an ongoing problem. After resting the router and clearing the table, while running uT the table slowly is filled up. Like I reset it yeasterday at 2 PM, didn't start uT and when my ISP people went home at 5 PM I had about 20 conns in the table, from normal mail etc. net activity. I started uT and it's been running overnight, and at 10 AM I have about 1000 conns, at Noon about 1300 and I assume it continue to increase and will let it as I am curious to see what happens here in my end when the table gets full. It possibly can tell me something.

I was just think of which OS you reffers to in your explaination, the one router is running on or the one on my client computer where uT is running? Of course I wouldn't be surprised if Windows turns out to be the evil one here ;-)

And wether if it's a bug (or setting thing) in uT or not, I think it's vital to figure it out. Not only to me but also for anyone else having a similar connection arrangement. Running uT will get them in to those problems, sooner or later and it could cause a lot of grief in different ends.


I thought of this, as I am running an Outpost Firewall on my local computer and it set the rules for which ports in and out allowed and for different programs, like I only have 1 port in for making connections to uT. Isn't my firewall also kind a router and the entity that actually opens and closes connections with my gateway router, and as such also is responsible for maintaining these connections?

I noticed one thing, Outlook had 4 connections opened in Firewall, opened at different times, the oldest since yesterday. I closed down all open windows of Outlook so only main instance remained but still all 4 connections was there. Not until I closed Outlook completely all 4 connections closed. Maybe I am on to something here, will watch it a bit more though, and in such case I should take this to the Outpost forums instead, of course.

Link to comment
Share on other sites


This topic is now archived and is closed to further replies.

  • Create New...