Re: 2.6.9 NAT problem

From: Bill Davidsen
Date: Tue Dec 21 2004 - 11:45:01 EST

Bodo Eggert wrote:
Bill Davidsen wrote:

Antonio Pérez wrote:

add this:
echo 0 > /proc/sys/net/ipv4/tcp_bic
echo 0 > /proc/sys/net/ipv4/tcp_ecn
echo 0 > /proc/sys/net/ipv4/tcp_vegas_conf_avoid

I've seen this and similar advice for other problems, and have disabled=

ecn for several systems with networking ailments myself. Would it be
better to have some of these off by default rather than have multiple
versions of these problems appear into the future?

Disabeling ecn is a workaround for b0rken firewalls and may result in
using more bandwidth than nescensary. If disabeling ecn helps, dump the
firewall and get something that supports basic internet standards (or
ask the owner to do this).

Like many other parameters, ecn can improve performance but may result in a non-functional network. Based on that I still think it's better for the default to be "works" and use of ecn or other tuning parameters such as reducing timeouts should be "tuning" instead.

Adding a few printk's seems to show that ecn is not so common that it needs to be on by default. I suspect that the main use of ecn code is in fighting with those broken routers and firewalls rather than improving performance.

-bill davidsen (davidsen@xxxxxxx)
"The secret to procrastination is to put things off until the
last possible moment - but no longer" -me
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