From owner-freebsd-net@FreeBSD.ORG  Sun Apr 29 16:02:51 2012
Return-Path: <owner-freebsd-net@FreeBSD.ORG>
Delivered-To: freebsd-net@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52])
	by hub.freebsd.org (Postfix) with ESMTP id 1DA2A10657A5
	for <freebsd-net@freebsd.org>; Sun, 29 Apr 2012 16:02:51 +0000 (UTC)
	(envelope-from lev@FreeBSD.org)
Received: from onlyone.friendlyhosting.spb.ru (onlyone.friendlyhosting.spb.ru
	[46.4.40.135]) by mx1.freebsd.org (Postfix) with ESMTP id CE6928FC0A
	for <freebsd-net@freebsd.org>; Sun, 29 Apr 2012 16:02:50 +0000 (UTC)
Received: from lion.home.serebryakov.spb.ru (89.112.15.178.pppoe.eltel.net
	[89.112.15.178]) (Authenticated sender: lev@serebryakov.spb.ru)
	by onlyone.friendlyhosting.spb.ru (Postfix) with ESMTPA id E13B14AC32
	for <freebsd-net@freebsd.org>; Sun, 29 Apr 2012 20:02:49 +0400 (MSK)
Date: Sun, 29 Apr 2012 20:02:48 +0400
From: Lev Serebryakov <lev@FreeBSD.org>
Organization: FreeBSD
X-Priority: 3 (Normal)
Message-ID: <1561150913.20120429200248@serebryakov.spb.ru>
To: freebsd-net@freebsd.org
In-Reply-To: <1311430753.20120429184752@serebryakov.spb.ru>
References: <75233009.20120429183559@serebryakov.spb.ru>
	<1311430753.20120429184752@serebryakov.spb.ru>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable
Subject: Re: IPv6 MTU discrovery -- how should it work?
X-BeenThere: freebsd-net@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
Reply-To: lev@FreeBSD.org
List-Id: Networking and TCP/IP with FreeBSD <freebsd-net.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-net>
List-Post: <mailto:freebsd-net@freebsd.org>
List-Help: <mailto:freebsd-net-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-net>,
	<mailto:freebsd-net-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 29 Apr 2012 16:02:51 -0000

Hello, Lev.
You wrote 29 =D0=B0=D0=BF=D1=80=D0=B5=D0=BB=D1=8F 2012 =D0=B3., 18:47:52:

LS>>   When I connect to external server twice, and run tcpdump in one
LS>> session for another one, and then try to use second (sniffed) session
LS>> for bulk transfer, I can clearly see, that server tries to send IPv6
LS>> packets with size 1420 to my local  network  many  times  and  doesn't
LS>> get any answer, so it is MTU problem for sure, but how it could be fix=
ed?
  And  I can not set mtu less than 1280 on gif0, and my IPv4 interface
only  have  1460, as it is PPPoE interface. Maybe, problem is here, as
MTU 1280 assumes outer MTU is 1500?

--=20
// Black Lion AKA Lev Serebryakov <lev@FreeBSD.org>