Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757312Ab2EVRxv (ORCPT ); Tue, 22 May 2012 13:53:51 -0400 Received: from mail-ee0-f46.google.com ([74.125.83.46]:63215 "EHLO mail-ee0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754038Ab2EVRxt (ORCPT ); Tue, 22 May 2012 13:53:49 -0400 Subject: Re: tcp timestamp issues with google servers From: Eric Dumazet To: Vijay Subramanian Cc: Miklos Szeredi , netdev@vger.kernel.org, linux-kernel@vger.kernel.org In-Reply-To: References: <87r4ujno34.fsf@tucsk.pomaz.szeredi.hu> <1337278363.3403.39.camel@edumazet-glaptop> <87zk90s0em.fsf@tucsk.pomaz.szeredi.hu> <1337701259.3361.208.camel@edumazet-glaptop> <87mx50rz34.fsf@tucsk.pomaz.szeredi.hu> <1337705285.3361.229.camel@edumazet-glaptop> Content-Type: text/plain; charset="UTF-8" Date: Tue, 22 May 2012 19:53:43 +0200 Message-ID: <1337709223.3361.281.camel@edumazet-glaptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1116 Lines: 30 On Tue, 2012-05-22 at 10:38 -0700, Vijay Subramanian wrote: > >> Maybe tcptraceroute[1] can help you figure this out. > >> > >> [1] http://michael.toren.net/code/tcptraceroute/ > > > > > > The transparent proxy can intercept TCP connections to port 80/443, and > > let ICMP being NATed by the box. > > Just to be clear..tcptraceroute uses TCP SYN packets to trace the > route instead of using ICMP packets used by vanilla traceroute > precisely because > of the issue you raised. > The idea is that if the connection is getting terminated at a > middlebox, the trace will end there. Otherwise, the trace route will > end > at destination (google in this case). This avoids the problems of ICMP > and TCP flows being treated differently by the middlebox. > Is this approach workable? Yes probably, thanks for detailed description (I indeed thought it was traceroute) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/