From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1JMjZC-00066g-6h for qemu-devel@nongnu.org; Wed, 06 Feb 2008 07:39:54 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1JMjZA-00064q-KN for qemu-devel@nongnu.org; Wed, 06 Feb 2008 07:39:53 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1JMjZA-00064j-Ff for qemu-devel@nongnu.org; Wed, 06 Feb 2008 07:39:52 -0500 Received: from mx1.redhat.com ([66.187.233.31]) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1JMjZA-0001ot-Dc for qemu-devel@nongnu.org; Wed, 06 Feb 2008 07:39:52 -0500 Message-ID: <47A9AA7C.9030103@redhat.com> Date: Wed, 06 Feb 2008 13:39:24 +0100 From: Gerd Hoffmann MIME-Version: 1.0 Subject: Re: [Qemu-devel] Making qemu use 10.0.3.x not 10.0.2.x References: <18344.18661.39309.29838@mariner.uk.xensource.com> <414CDEB1-8E31-4FAF-BE6F-1625F7FA77A6@web.de> <20080205.084836.74710742.imp@bsdimp.com> <20080205005142.GD4368@implementation> <20080205162206.38J1B.215136.root@eastrmwml22.mgt.cox.net> <200802052129.26282.paul@codesourcery.com> <20080206014031.GA5042@shareable.org> <20080205124219.EBPKE.19922.root@eastrmwml27.mgt.cox.net> <18345.36535.82205.721504@mariner.uk.xensource.com> In-Reply-To: <18345.36535.82205.721504@mariner.uk.xensource.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit 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 Cc: andreas.faerber@web.de, Asheesh Laroia Hi, > Using a (once) randomly-chosen default greatly reduces the odds of > that happening. Many many people foolishly choose 10.0.{0,1,2,3}.x. > Many fewer choose (say) 172.30.206.x. So the fixed qemu default > should be 172.30.206.x, or some other range also chosen at random. A few years back I've worked for a web company, wrote the border router firewall rules, had some rules in there to catch packages with rfc1918-private addresses in public network. Watching the statistics showed that the 172.16/12 range was _much_ less used than 10/8 and 192.168/16. I think 10/8 to be used by companies alot. 192.168.$smallnumber.0/24 seems to be a quite common default for DSL routers and the like. Thus picking a random /24 network from 172.16/12 as new default value has a pretty good chance to vastly reduce the number of clashes with existing setups. HTH, Gerd -- http://kraxel.fedorapeople.org/xenner/