Kernel:IP TCP ECN

[Barry K. Nathan]

On Sun, Jan 18, 2004 at 03:25:49PM -0500, seth vidal wrote:
> umm jef, it's /proc/sys option.
> 
> you can set it at run time.

Mandrake (since 8.2 or so -- one of the 8.x releases anyway) has
been shipping their kernels with the ECN option enabled, then adding
this to /etc/sysctl.conf:

# Disable ECN
net.ipv4.tcp_ecn = 0

That way, they disable it by default, but people who want it can
re-enable it without recompiling the kernel. The downside (at least with
the Mandrake implementation) is that some (but maybe not all; I don't
remember the details right now) people got the new kernel but not the
/etc/sysctl.conf change when upgrading from older Mandrake releases, so
they happened to get ECN enabled by mistake.

Just mentioning this for what it's worth...

-Barry K. Nathan <barryn at pobox.com>