Red Hat Bugzilla – Bug 117665
TCP ECN should be disabled by default until the rest of the world stops sucking
Last modified: 2014-03-16 22:43:00 EDT
This isn't technically a bug in any Linux software, but the
interoperability problems are going to confuse the hell out of users
Basically, 2.6 kernels have TCP ECN enabled by default. Unfortunately,
everybody else craps themselves when they see packets with the ECN bit
set, resulting in "myserious web sites that I can't connect to"-type
So, until the rest of the networking world is dragged kicking and
screaming into, well, 1999 or so, /etc/sysctl.conf should have
"net.ipv4.tcp_ecn = 0" in it.
Created attachment 98345 [details]
A handy-dandy patch to the three flavors of sysctl.conf
New! and Improved! Bug: Now with Minimal Effort Required!
Nothing gets fixed until something breaks. So it's good to break
things in order to get things fixed. Minor break is not fixed, major
is. Better break more when you breaking things. Keep the default.
That doesn't help upgrades though. Arjan: what's the plan on the
*** Bug 117745 has been marked as a duplicate of this bug. ***
I don't think this is going to be changed in sysctl.conf. I believe
the kernel defaults to off these days.