From mboxrd@z Thu Jan 1 00:00:00 1970 From: Just Marc Subject: Re: Disabling "TCP Treason uncloaked" Date: Wed, 03 May 2006 13:49:05 +0100 Message-ID: <4458A6C1.90103@corky.net> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org Return-path: Received: from corky.net ([212.150.53.130]:62156 "EHLO zebday.corky.net") by vger.kernel.org with ESMTP id S965157AbWECLuL (ORCPT ); Wed, 3 May 2006 07:50:11 -0400 To: Herbert Xu In-Reply-To: Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Hi, > Just Marc wrote: > >> We're now at 2.6.16.12 and it is still showing thousands of times a day >> on a busy web server, have all the bugs been discovered yet? >> > > There are no known bugs on the RX side in 2.6.16 that would cause this. > The few busy web servers that I have access to do not see this message > at all. > > So either your web server is somehow attracting a lot of buggy TCP stacks, > or there could be a dodgy gateway in your path that is mucking with the > TCP windows. > > You're right, actually this box serves http/ftp file transfers only, it's a mirror with a large amount of downloads a day. On a pure html/image web server that is just as busy, there are only a few of these messages, one or two a day. > I suggest that you do a tcpdump to see what it looks like. It might turn > out that we do still have a bug on our RX side. > I gave it another look, many of the prints are repeat prints for the same remote IPs, > BTW, this message is already under net_ratelimit so I don't see any > urgency in getting rid of it completely. If we're going down the > path of disabling it, we probably should go for something more global > rather than a sysctl that controls this one message. > I agree, however, I think it's pretty good to allow an admin to toggle it off completely. Maybe that's all we need, really. Thanks