From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.33) id 1BlxB1-0005PE-PC for qemu-devel@nongnu.org; Sat, 17 Jul 2004 17:57:03 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.33) id 1BlxAT-0005OZ-I3 for qemu-devel@nongnu.org; Sat, 17 Jul 2004 17:57:03 -0400 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.33) id 1BlxAT-0005OW-Cv for qemu-devel@nongnu.org; Sat, 17 Jul 2004 17:56:29 -0400 Received: from [171.71.176.72] (helo=sj-iport-3.cisco.com) by monty-python.gnu.org with esmtp (Exim 4.34) id 1Blx7m-0005aK-9X for qemu-devel@nongnu.org; Sat, 17 Jul 2004 17:53:43 -0400 Received: from edi-view2.cisco.com (edi-view2.cisco.com [144.254.112.71]) by sj-core-1.cisco.com (8.12.10/8.12.6) with ESMTP id i6HLqe8a022195 for ; Sat, 17 Jul 2004 14:52:41 -0700 (PDT) Received: (dfawcus@localhost) by edi-view2.cisco.com (8.11.2/CISCO.WS.1.2) id i6HLqe320352 for qemu-devel@nongnu.org; Sat, 17 Jul 2004 22:52:40 +0100 (BST) Date: Sat, 17 Jul 2004 22:52:40 +0100 From: Derek Fawcus Subject: Re: [Qemu-devel] network fails on windows Message-ID: <20040717225240.A15730@edi-view2.cisco.com> References: <200407171707.40476.matthias.jung@uni-dortmund.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <200407171707.40476.matthias.jung@uni-dortmund.de>; from matthias.jung@uni-dortmund.de on Sat, Jul 17, 2004 at 05:07:40PM +0200 Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org On Sat, Jul 17, 2004 at 05:07:40PM +0200, Matthias Jung wrote: > I was just on the verge of giving up until i tried one last thing: > I switched the mac address parameter. Til then I had used the mac > a3:b2:23:54:7e:cf which is a valid mac What do you mean 'valid'? - all values are 'valid'. > and windows did detect the interface > without flaws, but no network access was possible. > With 00:ff:7f:fc:36:d2 it suddenly worked, I only can imagine a bug in the > ne2000 windows driver, or in windows (95,98,2000 tested) itself, not allowing > such a mac. Well there would appear to be an important difference between those two MACs, one is multicast, one is unicast. The first two bits of the MAC address (as transmitted on the wire) are the group/unicast bit followed by the local/global bit. These generally translate into bits 0 and 1 of the first byte of the MAC address when written as above. So the first address has A3 - which is multicast and local, whereas the second address has 00 which is unicast and global. You may want to try the first address again but with the first byte replaced as follows: a2 - A local unicast address a0 - A global unicast address DF