From owner-freebsd-isp Mon Sep 30 9:36:26 2002 Delivered-To: freebsd-isp@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7D40537B401 for ; Mon, 30 Sep 2002 09:36:24 -0700 (PDT) Received: from smtpout.mac.com (smtpout.mac.com [204.179.120.86]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5A6E843E77 for ; Mon, 30 Sep 2002 09:36:23 -0700 (PDT) (envelope-from cswiger@mac.com) Received: from asmtp02.mac.com (asmtp02-qfe3 [10.13.10.66]) by smtpout.mac.com (Xserve/MantshX 2.0) with ESMTP id g8UGaMWI004636 for ; Mon, 30 Sep 2002 09:36:23 -0700 (PDT) Received: from bust ([12.38.161.88]) by asmtp02.mac.com (Netscape Messaging Server 4.15) with ESMTP id H39FGM00.VO1 for ; Mon, 30 Sep 2002 09:36:22 -0700 Date: Mon, 30 Sep 2002 12:36:21 -0400 Subject: Re: Multihoming alternatives Content-Type: text/plain; charset=US-ASCII; format=flowed Mime-Version: 1.0 (Apple Message framework v482) From: Chuck Swiger To: freebsd-isp@FreeBSD.ORG Content-Transfer-Encoding: 7bit In-Reply-To: <20020930155854.18500.qmail@linuxmail.org> Message-Id: X-Mailer: Apple Mail (2.482) Sender: owner-freebsd-isp@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org On Monday, September 30, 2002, at 11:58 AM, Paul Keith wrote: > First I would like to apologise if this is not the place for such > questions. > I am looking for links/tips/'intel' on building redundant/multihomed > network that sits on a /29, (to serve webpages and mail to its clients on > different AS's to produce proper redundancy), without resorting to BGP > configurations or coloating with a large backbone.Is this possible? In which case, your easiest bet is to run two data lines (DS-1's or whatever) in a redundant topology from one provider. With Cisco routers, I believe the term is "DHRP". The obvious problem is that if your upstream provider goes down, you're out of service. However, you can survive a failure of either data link or a local router, which covers several probable failure modes. Multihoming with two different network providers requires you to either have a /20 and be globally routable (via ARIN, and yes, you'll have to do BGP/EGP peering), or else you'll need to multihome your web server on seperate IP networks from seperate providers. DNS should round-robin the A records if you list several, but that still isn't perfect, since dumb clients won't, but it's better than nothing. Besides, if you do have a significant outage that will take at least hours to fix, you can adjust your DNS to disable the downed IP. > How will this DNS server run in a multihomed enviroment? Is it possible > to load balance across 2 or 3 DNS servers or am I being silly? Of course it's possible to load balance between multiple DNS servers; just list multiple NS records for the zone. While it's okay to run DNS on a multihomed box, you should not assume that a single machine with 2 interfaces is redundant. You should use several DNS servers, some offsite or located with someone else's ISP. -Chuck Chuck Swiger | chuck@codefab.com | All your packets are belong to us. -------------+-------------------+----------------------------------- "The human race's favorite method for being in control of the facts is to ignore them." -Celia Green To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message