Problems with routers and P2P?

[azekeil]

After considerable problems getting Azureus to work nicely with kissycat1000's WRT54GSV4, I think I've found the answer.

The problem is simply that the number of connections Azureus and other P2P clients make overwhelms the router's connection tracking tables and it ends up dropping packets all over the place, slowing web connections to a crawl and making them unreliable.

One of the recent changes is decentralised tracking. This allows Azureus to circumvent problems if the tracker is no longer online. However it does this by initiating a lot of connections to other peers, and it is this which floods the poor little router.

On other clients such as µTorrent, decentralised tracking is called DHT.

The answer is to disable this, and also reduce the number of connections the P2P client makes - I've set kissycat1000's to 30 max connections globally.

On the router you should disable any QoS because this may also cause the router to choke on the number of packets/destinations.

Currently kissycat1000's router is set to reboot overnight, but I think I can probably take this out now.

I did initially try a different firmware which is reported to sort the problem out. The firmware I tried (DD-WRT) is in beta, and certainly we had problems with the GUI refusing to accept commands - but that could have been Azureus causing it to lock up at that point - I have not tried it now I've sorted out the Azureus problem.

A side note - the Linksys routers actually use linux under the hood, all except the latest WRT54GSV5, which has reduced flash memory and RAM and uses VxWorks, a proprietary embedded OS. If you're in to upgrading the firmware on your router, avoid these latest ones. Or, of course, use a linux box for your router anyway, and you can do all sorts of cool things like host your own webserver, email, proxy, calendar etc :)

Comments

[tefkas.livejournal.com]

It took me a little while to optimise μtorrent with the router, but I managed it eventually - I can't remember what number of connections, offhand, but I had to set up port forwarding on the router for both PCs (using different ports and both protocols).

I like μtorrent a lot, actually. It doesn't have that many frills, granted, but it's amazing for a 150k executable!

[azekeil.livejournal.com]

Yep. Far better than the bloatware of Azureus.. but then Azureus does come with lots of extras that I plan to investigate and make use of! :)

[serena-lesley.livejournal.com]

Thank you for allowing my internet connection to actually work, you're ace, you are! ;)

[meltie.livejournal.com]

Did you just encourage people to run applications on a gateway router? :o!

[azekeil.livejournal.com]

Yes, why not?

[meltie.livejournal.com]

It's something my peers always shouted at me for doing - running apps on a router/firewall. Physical seperation of important data from your first defense.

I never quite believed in it myself because if something compromises your firewall you've got bigger problems than them reading your mail off the spool...

[azekeil.livejournal.com]

Well quite - it might make sense in an enterprise environment, but in a home environment you want the most service for the least cost - that means running all on one machine. I dislike routers because of their limited capacity and trouble, and it's trivial to enable my 'services' machine to also be a router.

I don't believe it is much less secure with a well-configured system. Make sure all communications are secure, that there are no security concerns with the versions of applications you are using, use secure passwords (and possibly obscure usernames) and you shouldn't have too much trouble. I am not even running a firewall, as I just turn off services I don't want running. NAT protects my internal machines anyway.

[emilydongray.livejournal.com]

I think we had to do something similar with our linksys...maybe...*thinks back*

information

[chocojon.livejournal.com]

Azureus is a bit of bloatware but it is also Java based ... :-/ This means (to me, at least) that they can develop for one environment and it will work on any Java compliant system. AFAIK, utorrent is only available for Windows machines.

I have used Azureus for quite a while so I know it fairly well. I've found that Azureus can go a bit mental with CPU and memory usage if you have quite a few concurrent torrents. There are a lot of options and screens in Azureus but I've found tha utorrent has kept all the useful ones and it has an overall speed graph. This is a very limited view of utorrent so far though.

I was wondering what you so useful in Azureus that you couldn't find in utorrent? I'm almost converted to utorrent but am still testing both.

P.S. you can limit numbers of connections in the Transfers section in the Options page.

Re: information

[azekeil.livejournal.com]

Yes, everything you've said is right in the first paragraph. µTorrent was being developed for other platforms (linux and Mac I think) but development stalled, and they're looking for people to take it on again.

µTorrent does all the basics that Azureus does, except plugins. I'm becoming increasingly paranoid about getting slapped on the wrists, so plugins like the safepeer thing in Azureus are a must, and I'm also looking in to using one (or more) of the anonymous networks (Tor, I2P) for tracker transfer at least.

Yes, you can limit the number of connections in Azureus, but because of its plugin nature you have to also check in there, and other places. Even when it should be turned off, the distributed tracking thing still seems to carry on. If you want to see what I mean, try doing a netstat -n at the command line to see how many connections you have. With µTorrent when I tell it to limit to 30, I get 30 connections. With Azureus I still get several hundred, and the router tells me it's dropping packets because its connection table is full. Plus of course I get the typical crap connection problems.

Not sure if I've made it clear, but I'm now using µTorrent as it keeps the connection stable.