From owner-freebsd-net@FreeBSD.ORG Wed Aug 30 06:41:51 2006 Return-Path: X-Original-To: freebsd-net@FreeBSD.org Delivered-To: freebsd-net@FreeBSD.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9A05E16A4DE for ; Wed, 30 Aug 2006 06:41:51 +0000 (UTC) (envelope-from sivakumar.subramani@wipro.com) Received: from wip-ectls-mx3.wipro.com (wip-ectls-mx3.wipro.com [203.91.193.23]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8807E43D49 for ; Wed, 30 Aug 2006 06:41:49 +0000 (GMT) (envelope-from sivakumar.subramani@wipro.com) Received: from wip-ectls-mx3.wipro.com (localhost.localdomain [127.0.0.1]) by localhost (Postfix) with ESMTP id 68EC3224443 for ; Wed, 30 Aug 2006 12:11:46 +0530 (IST) Received: from blr-ec-bh01.wipro.com (blr-ec-bh01.wipro.com [10.201.50.91]) by wip-ectls-mx3.wipro.com (Postfix) with ESMTP id 5A03C224485 for ; Wed, 30 Aug 2006 12:11:46 +0530 (IST) Received: from blr-m3-msg.wipro.com ([10.114.50.99]) by blr-ec-bh01.wipro.com with Microsoft SMTPSVC(6.0.3790.1830); Wed, 30 Aug 2006 12:11:36 +0530 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Date: Wed, 30 Aug 2006 12:11:30 +0530 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: Testing on network interface - promisc mode. Thread-Index: AcbL/1OfCS6qCsJ2RKSSRBni/WDUtw== From: To: X-OriginalArrivalTime: 30 Aug 2006 06:41:36.0975 (UTC) FILETIME=[576195F0:01C6CBFF] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Subject: Testing on network interface - promisc mode. X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 30 Aug 2006 06:41:51 -0000 Hi, =0D I was using following steps to test the promisc mode on the network interface on my system on FreeBSD 6.1. =0D - On machine A, I updated the arp table with the a dummy MAC address (aa:bb:cc:dd:ee:ff) for the remote interface on Machine B. #arp -s 17.1.1.110 aa:bb:cc:dd:ee:f =0D - On Machine B, I enabled promisc mode for the test N/W interface.=0D #ifconfig promisc=0D =0D - Started tcpdump on Machine A, for capturing the packets.=0D =0D - On Machine A, I ping to the remote Interface of the Machine B #ping -c2 17.1.1.110 - Ping went through fine and Tcpdump is displaying both ICMP request and ICMP reply. =0D I could understand that machine B receives ICMP request as promisc mode is enabled. But it was not suppose to send ICMP reply as the packet was not intended for this machine (I mean the ICMP REQUEST PACKET contain some dummy MAC address). It was supposed to be discarded. =0D After testing the above steps, I could see the ICMP REPLY from MACHINE B and ICMP REPLY contain original Mac address in the Source MAC address field in the Ethernet header. =0D Please let me know whether the above behavior is correct and acceptable. =0D Thanks, ~Siva =0D The information contained in this electronic message and any attachments to= this message are intended for the exclusive use of the addressee(s) and= may contain proprietary, confidential or privileged information. If you= are not the intended recipient, you should not disseminate, distribute or= copy this e-mail. Please notify the sender immediately and destroy all= copies of this message and any attachments.=0D WARNING: Computer viruses can be transmitted via email. The recipient= should check this email and any attachments for the presence of viruses.= The company accepts no liability for any damage caused by any virus= transmitted by this email. =0D www.wipro.com