Re: 2.6.17 regression: Very slow net transfer from some hosts

From: Stephen Hemminger
Date: Tue Apr 11 2006 - 18:33:41 EST


On Tue, 11 Apr 2006 23:20:42 +0100
Daniel Drake <dsd@xxxxxxxxxx> wrote:

> John Heffner wrote:
> > This is almost certainly due to a buggy firewall that doesn't understand
> > TCP window scaling. I've usually seen this in the past with OpenBSD
> > firewalls. Do you have one of these in your path?
>
> At home I'm behind a Linux gateway box currently running 2.6.15-rc6 - I
> am connected through ethernet to that.
>
> At my student house I am connected wirelessly to a Linksys WRT54Gv5
> router (the model that doesnt run Linux).
>
> I have reproduced it at both those locations (same ISP).
>
> This is very familiar, and I just found the article I was thinking of:
> http://lwn.net/Articles/92727/
>
> I was also hit by that bug, on the same collection of websites, but that
> particular problem was fixed for 2.6.8 or so. So I guess it is extremely
> likely that my ISP has broken routers. nmap isn't able to identify the
> OS of any ISP routers in my path.

We never fixed it, its kind of hard to fix other peoples equipment ;-)

>
> It's a huge ISP over here, so contacting them over technical matters is
> not easy...
>
> Thanks,
> Daniel
>

Turn off TCP window scaling, your performance will be limited but about
as good as you can get with a corrupting firewall in between.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/