Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 1 Jul 2002 19:24:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 1 Jul 2002 19:24:45 -0400 Received: from w007.z208177138.sjc-ca.dsl.cnc.net ([208.177.141.7]:57514 "HELO mail.gurulabs.com") by vger.kernel.org with SMTP id ; Mon, 1 Jul 2002 19:24:44 -0400 Subject: Is ff:00:00:00:00:00 a broadcast frame? From: Dax Kelson To: linux-kernel@vger.kernel.org In-Reply-To: References: Content-Type: text/plain Content-Transfer-Encoding: 7bit X-Mailer: Ximian Evolution 1.0.3 (1.0.3-6) Date: 01 Jul 2002 17:27:11 -0600 Message-Id: <1025566031.5129.179.camel@porthos> Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2527 Lines: 66 In the "earlier" 2.4 kernels (those that shipped/errata with RHL 7.1 ~2.4.6), an ethernet frame destined to ff:00:00:00:00:00 were not processed and passed up the stack. Now, with "current" 2.4 kernels (RHL 7.2 errata, and RHL 7.3 2.4.9-2.4.18), the same frame IS processed and passed up the stack. The hardware is identical, the NICs are 3c905C. Is this an intentional optimization/bug? Here is an ARP request encapsulated in a "bogus" ethernet frame (look at the layer 2 destination). A RHL 7.3 (2.4.18) system will respond (see Frame 2 below) to this frame, an older RHL 7.1 (2.4.6) system will not respond. Frame 1 (42 on wire, 42 captured) Arrival Time: Jul 1, 2002 17:16:35.565996000 Time delta from previous packet: 1.009672000 seconds Time relative to first packet: 1.009833000 seconds Frame Number: 3 Packet Length: 42 bytes Capture Length: 42 bytes Ethernet II Destination: ff:00:00:00:00:00 (ff:00:00:00:00:00) Source: ff:00:00:00:00:00 (ff:00:00:00:00:00) Type: ARP (0x0806) Address Resolution Protocol (request) Hardware type: Ethernet (0x0001) Protocol type: IP (0x0800) Hardware size: 6 Protocol size: 4 Opcode: request (0x0001) Sender MAC address: 00:01:03:de:56:a4 (00:01:03:de:56:a4) Sender IP address: 10.100.0.8 (10.100.0.8) Target MAC address: 00:00:00:00:00:00 (00:00:00:00:00:00) Target IP address: 10.100.0.10 (10.100.0.10) Frame 2 (60 on wire, 60 captured) Arrival Time: Jul 1, 2002 17:16:35.566146000 Time delta from previous packet: 0.000150000 seconds Time relative to first packet: 1.009983000 seconds Frame Number: 4 Packet Length: 60 bytes Capture Length: 60 bytes Ethernet II Destination: 00:01:03:de:56:a4 (00:01:03:de:56:a4) Source: 00:01:03:de:57:37 (00:01:03:de:57:37) Type: ARP (0x0806) Trailer: 00000000000000000000000000000000... Address Resolution Protocol (reply) Hardware type: Ethernet (0x0001) Protocol type: IP (0x0800) Hardware size: 6 Protocol size: 4 Opcode: reply (0x0002) Sender MAC address: 00:01:03:de:57:37 (00:01:03:de:57:37) Sender IP address: 10.100.0.10 (10.100.0.10) Target MAC address: 00:01:03:de:56:a4 (00:01:03:de:56:a4) Target IP address: 10.100.0.8 (10.100.0.8) - 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/