From owner-freebsd-isp Sun Mar 23 9:20:58 2003 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 2E57537B405 for ; Sun, 23 Mar 2003 09:20:56 -0800 (PST) Received: from mgw1-out.MEIway.com (mgw1.meiway.com [212.73.210.75]) by mx1.FreeBSD.org (Postfix) with ESMTP id EB9AB43FB1 for ; Sun, 23 Mar 2003 09:20:53 -0800 (PST) (envelope-from LConrad@Go2France.com) Received: from VirusGate.MEIway.com (virus-gate.meiway.com [212.73.210.91]) by mgw1-out.MEIway.com (Postfix Relay Hub) with ESMTP id 4C600EF69E for ; Sun, 23 Mar 2003 18:04:35 +0100 (CET) Received: from localhost (localhost.meiway.com [127.0.0.1]) by VirusGate.MEIway.com (Postfix) with SMTP id 17BC65D009 for ; Sun, 23 Mar 2003 18:24:42 +0100 (CET) Received: from mail.Go2France.com (ms1.meiway.com [212.73.210.73]) by VirusGate.MEIway.com (Postfix) with ESMTP id B240D5D008 for ; Sun, 23 Mar 2003 18:24:41 +0100 (CET) Received: from tx0-go2france-c.Go2France.com [24.242.169.51] by mail.Go2France.com with ESMTP (SMTPD32-6.06) id A18463B01F6; Sun, 23 Mar 2003 18:40:20 +0100 Message-Id: <5.2.0.9.0.20030323110847.03d78188@mail.go2france.com> X-Sender: LConrad@Go2France.com@mail.go2france.com X-Mailer: QUALCOMM Windows Eudora Version 5.2.0.9 Date: Sun, 23 Mar 2003 11:20:29 -0600 To: freebsd-isp@freebsd.org From: Len Conrad Subject: Re: Server redundancy over 2 co-locations In-Reply-To: <5.2.0.9.0.20030323164230.047f5650@mail.monkey-online.net> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; format=flowed 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 >-The world famous F5 Networks 3-DNS controller; You pay for a lot of fancy >things that I don't need yep >because it can ballance the connection over multiple locations, which I >don't need. nope >-Some sort of round-robin system, that runs on both locations (primary at >location 1 and secondary at location 2) and checks if location 1 is still >up, and otherwise points to location 2. This is pretty easy to do with a dynamic, sandboxed sub-zone for a www.domain.com zone. I helped an on-line travel site set up his Radware Linkproof box and got to learn all about this approach with the Radware people. I have a (commercial) scheme like this for load-balancing and failing over of MX gateways as part of IMGate. >I don't know if I'll get problems with TTL times All DNS load-balancing and/or failover tactics require tiny TTL on the A records. >, DNS caches Your unwanted effects of caching are minimized with the short TTL > etc with the round-robin system, or with the 3-DNS controller. > >What are your thoughts and experiences on this subject? round-robin won't give you primary/secondary failover. It will give you dumb load distribution, so when one ip is down, it will still see traffic (that will time out, not a desirable "user experience") since DNS will still be passing out the RR-set of A records for the www domain name. To do exactly what you want, there used to be a project called "fez" (nothing to do with Arabs, you Super Patriots) on sourceforge but has been gone quite a while. You can find Linkproof boxes on eBay for the typical fraction of $new. Len _____________________________________________________________________ MenAndMice.com/DNS-training: Austin; Chicago; San Jose; Toronto IMGate.MEIway.com: anti-spam gateway, effective on 1000's of sites, free To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-isp" in the body of the message