internet not working with arjan's 2.6 testkernels

[Michael Kearey]

Tim Kossack wrote:
> i'm using the arjan (hope that's spelled right) testkernels with rh9/xd2
> on my sony pcg-z600lek notebook, but all kernels newer than
> 2.6.0-0.test5.1.36 seems to have problems connecting to the
> internet. my notebook is connected to a sitecom-router, and in this way
> (plus another switch connected to the sitecom-router) also to 6 or 7
> windows-pcs. interestingly, i can connect to them via smb/nautilus and
> can copy files from them to my pc with the new(est) testkernel running,
> but when i want to fetch my mails via evolution or to browse with
> galeon, the resp. program tries to connect, but there seems to be simply
> no data coming. after a while, in galeon, i get the
> "timelimit"-error-message.
> note that when booting, i get the green "ok-message" for eth0 and again,
> i can copy files from other computers in my network flawlessly...
> my notebook's built-in network-adapter is a widely used intel
> (pro?)-chipset (sorry for not knowing the exact type, if needed, i'll
> try to find out the exact type).
> 
> so my question-is this a known thing, and is it fixable from my side-or
> a bug in the (newer) kernels?


I beleive ECN (Explicite Congestion Notification) is set on in the kernel.

To confirm , 'cat /proc/sys/net/ipv4/tcp_ecn'

If 1 then it's on. Some routers and or firewalls drop packets with the 
ECN bits set.

To turn off, 'echo '0' >/proc/sys/net/ipv4/tcp_ecn'

Cheers,
Michael