Recently I upgraded my internet connection to a VDSL line, receiving the ZTE router mentioned in the thread title from my ISP (It's in Greece so I doubt naming them would make much sense to you). Everything worked smoothly and very plug-and-playish until I started up utorrent, which up to that day, had been working super fine.
Now it turns out, the second I turn the program on, it completely kills my internet/dns. I cannot access anything on the web and no torrent will download. There is no torrent ban on my ISP, I checked (Greece is bad, but not THAT bad. Yet.)
I asked customer support and they told me to try lowering the number of concurrent connections uTorrent is using, I tried a million different configurations, nothing doing. The only way to get internet back was to shut the program down and wait a minute for my connection to reset.
I suspect this has to do with a router setting, it's not an ISP problem, in that internet service is seamless on everything else. Me and many fellow Greeks are having this problem currently so any help will be greatly appreciated and hailed with a Golden Halo of All Knowing Geekdom for you.
- TCPip driver might be hitting the connection limit set in your registry.
- connections have to undergo a wait timeout after a disconnection
I don't recall how long the default is (30 seconds or 300 seconds).
- Some ISP have software that will slow your connection down if they think you use too much bandwidth over short period of time. they can do this over small time windows and remove your limits real time over short windows of say 30 mins. They want to slow your band bandwidth usage but want to keep you connected so you will not generate a support call to them which costs them money.
Anyway, the driver will block new connections until the wait timeout expires even if all the connections have been closed. This was implemented to slow down malware and to help limit torrents that were running without the machines owners knowledge.
for example: say 200 total connections allowed, you do the following
start 100 connections : works as expected
start another 100 connections : works as expected
start 1 more connection: fails because connection limit reached
stop 100 connection: works as expected (you now have 100 active connections and 100 wait pending connections being closed down)
now attempt to start 1 connection and it fails because your connection limit has been reached. 100 active connections and 100 pending close connections in the wait time out state.
How to fix: if you really want to share your torrents there should be a registry settings the total number of connections and the wait timeout period best to google for the the settings.
run the tool before you start your torrent, then see what happens while it runs, then after you close the torrent. the connections dont' get cleaned up for a while.
if you open an close a bunch of connections in a short period of time you will end up
with a bunch of connections in TIME_WAIT state for several minutes. This can prevent further connections depending on your max number of connections allowed by your TCP transport driver. This we are not talking about the number of connections used by your torrent software.
also, bugs can really mess this whole scheme up. bugs in the transport, bugs in the network card, bugs in the router, bugs on the other guys machine transport, his netcard. the whole round trip path from your machine, across your hardware, your IPS hardware, the internet backbone, into some other ISP, to someones cable modem, router, ethernet card, ethernet card driver, tcpip driver, OS and to their copy of torrent software. then back, and it is not the same path.
first get your torrent to make one connection thru your firewall and router. there will have to be a port open to do that. you will have to look at your software to see what port it needs to open.
Terrific post! Ok, I went to cmd and did as you told me.
It dumped a bunch of active connections and two pertaining to uTorrent ( I spotted that by the port number used). The first one was TIME_WAIT and then it threw in another as LISTENING and then nothing....torrent was unresponsive, but at least the rest of my internet didn't crash horribly.
I filed a complaint with my ISP and they answered that there's some issue with my phone line and that they're looking into it. It sounds like BS to me though. If there was an issue, I wouldn't have internet at all, right? This is clearly something to do with utorrent...
Νο solution whatsoever sadly, after two visits from the in-house technician. Using Tixati torrent client I can download some stuff with a very incosistent rate and the internet coming and going during the download, definitely not a permanent solution.
They told me to give them till Monday to fix it and if they do nothing by then, I'm going back to simple, plain old DSL and my trusty LinkSys router!
I was expecting a bunch of connections in TIME_WAIT (50 or so). It sounds like some of your connections are blocked. maybe by the windows firewall, or the ports not being forward in your router. Sometimes cable modems get "confused" and you can hit the reset and have the cable company automatically re-download its configuration info. If the cable company is blocking your port, you can configure your torrent for another port (less well known one) and it takes 15 mins before their software detects the usage spike and blocks you again. (at least that helps you figure out the problem)
sometimes cached DNS data is messed up and you can run
IPCONFIG.exe /flushdns to clear things out and try again.
Also, I do think under the new rules if the provider detects unlawful file sharing they can block your port but this is unlikely. All else fails you can just install microsoft
network monitor and watch all the network traffic and see where it is being rejected. I have seen cases where there were bugs in the cards network driver, each time you tried to send some packets the connection would be reset because of the bug. I did not find those until I did a sniffer trace with network monitor. the last 2 times I found that it was in a laptop network card (Atheros) both times I updated the driver and no connection resets and all worked as expected.