From owner-freebsd-questions@FreeBSD.ORG Wed Nov 7 16:28:12 2007 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 B79DF16A58C for ; Wed, 7 Nov 2007 16:28:12 +0000 (UTC) (envelope-from malcolm.clarke@brunel.ac.uk) Received: from astro.systems.pipex.net (astro.systems.pipex.net [62.241.163.6]) by mx1.freebsd.org (Postfix) with ESMTP id 823F213C49D for ; Wed, 7 Nov 2007 16:28:12 +0000 (UTC) (envelope-from malcolm.clarke@brunel.ac.uk) Received: from [192.168.0.101] (81-86-251-96.dsl.pipex.com [81.86.251.96]) by astro.systems.pipex.net (Postfix) with ESMTP id B4F18E0007CB for ; Wed, 7 Nov 2007 16:04:58 +0000 (GMT) Message-ID: <4731E220.3050006@brunel.ac.uk> Date: Wed, 07 Nov 2007 16:04:48 +0000 From: Malcolm Clarke User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: freebsd-questions@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: IP packet with options 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, 07 Nov 2007 16:28:12 -0000 I have configured a machine with 2 NIC and IPFW in a rather simplistic way as we are using it to emulate different link characteristics rather than as an actual firewall. 00100 4 355 pipe 1 ip from any to any via de0 in 00200 1 56 pipe 2 ip from any to any via de0 out 00300 0 0 pipe 3 ip from any to any via de1 in 00400 3 288 pipe 4 ip from any to any via de1 out 65535 4 246 deny ip from any to any The configuration works fine and traffic crosses the firewall without problem, except ICMP packets having timestamp or routing option, and these are not returned. Is there a way to allow these packets to enter/exit the firewall? Regards Malcolm -- --------------------------------------------------- Dr Malcolm Clarke Senior Lecturer in Data Communication Systems and Telemedicine Department of Information Systems and Computing Brunel University Uxbridge Middlesex UB8 3PH UK Tel: +44 1895 265053 Fax: +44 1895 251686 http://www.brunel.ac.uk/about/acad/siscm/research/themes/is/groups/bright/people ----------------------------------------------------