Re: Debian packaged 2.4.9 kernel prevents internet access to ISP ONLY?!?
On Fri, Aug 31, 2001 at 11:11:00AM -0400, Scott_Patterson@AndersonsInc.com wrote:
> I've have a strange problem here...
> On my system I have various Debian packaged kernels (2.2.19 and 2.4.9).
> When I boot into my 2.2.19 kernel, my internet connection is fine. I can
> access all sites and download my email.
> However, when I boot into 2.4.9, I can access all sites EXCEPT my ISP. It
> just hangs there. I'm not too interested in viewing the webpage as much as
> I am getting my email! How or why is this happening? Any ideas how to
> debug/fix it?
> Oh yeah, I can compile my own kernel, but I need the stock kernel to test
> various pieces of hardware that are not usually on my machine (everything
> is compiled for the stock kernels vs my custom kernel just containing my
> normal hardware setup).
I really can't see it being enabled in a stock kernel, but it could be ECN
Explicit Congestion Notification (ECN) allows routers to notify
clients about network congestion, resulting in fewer dropped packets
and increased network performance. This option adds ECN support to the
Linux kernel, as well as a sysctl (/proc/sys/net/ipv4/tcp_ecn) which
allows ECN support to be disabled at runtime.
Note that, on the Internet, there are many broken firewalls which
refuse connections from ECN-enabled machines, and it may be a while
before these firewalls are fixed. Until then, to access a site behind
such a firewall (some of which are major sites, at the time of this
writing) you will have to disable this option, either by saying N now
or by using the sysctl.
grep CONFIG_INET_ECN /boot/config-2.4.9
and see what turns up...
If its enabled I would think a 'echo 0 > /proc/sys/net/ipv4/tcp_ecn' would
kill it off! :)