From owner-freebsd-questions@FreeBSD.ORG Wed Feb 27 09:32:09 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C0C101065676 for ; Wed, 27 Feb 2008 09:32:09 +0000 (UTC) (envelope-from _lion_2000@mail.ru) Received: from ards.ru (mail.ards.ru [212.76.164.163]) by mx1.freebsd.org (Postfix) with SMTP id 17E1713C4F3 for ; Wed, 27 Feb 2008 09:32:08 +0000 (UTC) (envelope-from _lion_2000@mail.ru) Received: (qmail 45172 invoked by uid 0); 27 Feb 2008 14:05:27 +0500 Received: from (10.1.201.55); 27 Feb 2008 09:05:27 -0000 X-lion-scan: 0 X-RELAYCLIENT: 1 Received: from wtm-ards-itoa01.net.ards.corp (HELO wtmardsITOA01) (10.1.201.55) by mail.net.ards.corp with SMTP; 27 Feb 2008 14:05:27 +0500 From: "Sergey" <_lion_2000@mail.ru> To: Date: Wed, 27 Feb 2008 14:05:27 +0500 Message-ID: <000301c8791f$e529fb60$37c9010a@Net.ARDS.Corp> MIME-Version: 1.0 Content-Type: text/plain; charset="koi8-r" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 11 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3198 Thread-Index: Ach5H+T6KHUcY9iCQJK6rfGPLkYSmA== Subject: Path MTU netstat X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Feb 2008 09:32:09 -0000 I want to see currently discovered Path MTU. I tried netstat -rnaW, but it doesn't show any cloned routes, but i clearly see Path MTU discovery working, by watching tcpdump tracing. An application sends full sized packet with DF bit, receives ICMP Unreach Frag message and retransmits downsized packet again. I need this, because there is another 6.2-RELEASE-p3 host, which doesn't perfom Path MTU discovery, although: # sysctl -a | grep path_mtu net.inet.tcp.path_mtu_discovery: 1 I tried disabling firewall, simplifying routing, but none helps. Anyone help?