Bittorrent Weirdness...

[Bruco]

Here's one I could definitely use help with.

I'm running FreeBSD 6.3 with Azureus (or "Vuze" I guess it's called now) 3.0.3.4 installed.

When I open a .torrent file in Azureus it starts out looking normal - picks up the seeds and the download speed starts climbing. Then, after a few minutes, the download speed drops to almost nothing and eventually zero.

Of course, my first thought was that my dastardly ISP was shaping the traffic - but then I opened one of the same torrents on a WinXP box (with some old version of Azureus) and zoom! - I had super-fast download speeds and the file was downloaded in no time.

This is so strange. I've verified that the port is forwarded properly on my router (and checked with Azureus' built-in NAT check - it's fine). A netstat shows connections to the seeders on that port as well. I have the Speed Scheduler plugin installed, but this behavior manifests whether or not Speed Scheduler is activated. I've tried running Azureus as both a regular user and as root, just in case. Same results.

Perhaps most interesting, if I change my incoming port in Azureus, save the change, then go stop and start my downloads, they will once again pick up download speed... then after a moment drop to zero again. It's almost as though it's accepting the connections, then something is noticing them and putting a stop to it.

So, is the OS doing something I don't know about? I know if you port scan a FreeBSD box it will start putting limitations on connections automatically - is that what it's doing? (I know Bittorrent can generate a lot of connections.) Is there some utility I could run that would give me some more insight into this if it's potentially a networking issue?

Or is this some kind of bizarre application issue with Azureus? Should I try a different Bittorrent client? Should I try the Windows version of Azureus in Wine? (I've never used Wine - but I'm willing to give it a shot.) Has anyone seen similar behavior to this at some point?

Thanks.

[richardpl]

What are your firewall settings?
What are your general network non-defaults settings?

[Bruco]

I have an IP and subnet mask set in rc.conf. I also have a defaultrouter and hostname specified.

I'm not running a firewall on the FreeBSD box itself - or rather, I never configured one, so I would ASSUME I'm not. I am running inetd (ftp and samba). I'm also running apache, sshd, and ntpd. And a little web server that came from Highpoint for RAID management.

As far as my router's firewall - it's running DD-WRT, so an SPI firewall that's using Iptables I believe. And like I said, it seems to do the port forwarding properly, and I had no issues on that WinXP box.

I hope I answered your questions - if there's something else you are looking for please let me know. Thanks for the response!

[anomie]

As of this moment, my understanding is Azureus's NAT traversal capabilities are not great. See Comparison of BitTorrent software.

Which is to say: before placing the blame at the OS level, be sure to try a different BT client. Allow me to suggest net-p2p/transmission. I've been using it for some time, and it handles NAT traversal properly.

[Bruco]

Oh, I'm not blaming the OS, necessarily! I was far more suspicious of the *nix version of Azureus than anything else.

I tried Transmission out for one of the torrents and it worked perfectly. So yes, we are definitely looking at an app issue. Isn't it bizarre that some two-year-old version of Azureus worked on a WinXP box but a much newer version failed on this BSD box?

Anyway, Transmission is great and thanks for the suggestion. I'll miss my beloved Speed Scheduler plugin, but I can probably whip up some cron jobs that run commands on Transmission and do basically the same thing.

Thanks!

[anomie]

Originally Posted by Bruco

Anyway, Transmission is great and thanks for the suggestion.

No problem -- I should have also mentioned (if you didn't discover it already) that there is a CLI in addition to the GTK2 interface. I personally use the latter. IIRC, you should be able to make a selection for one or both at port configuration time.

[Bruco]

Yep, I've installed both. I need to see if the CLI will interact with the GTK version at all (setting max down/up speeds) so I could create some cron jobs. I think either that or transmission-daemon will do it. I've got some reading to do!

[enpey]

deluge allows you to set two max up/down speeds with an hour by hour week calendar allowing you to set the limits for each hour to either of the two speeds or to zero...

[Bruco]

Deluge, eh? I'll try it out, thank you.