From owner-freebsd-questions@FreeBSD.ORG Wed Dec 28 13:07:37 2011 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E9E0A106564A for ; Wed, 28 Dec 2011 13:07:37 +0000 (UTC) (envelope-from vas@mpeks.tomsk.su) Received: from relay2.tomsk.ru (relay2.tomsk.ru [212.73.124.8]) by mx1.freebsd.org (Postfix) with ESMTP id 35F9C8FC15 for ; Wed, 28 Dec 2011 13:07:36 +0000 (UTC) X-Virus-Scanned: by clamd daemon 0.93.1 for FreeBSD at relay2.tomsk.ru Received: from admin.sibptus.tomsk.ru (account sudakov@sibptus.tomsk.ru [212.73.125.240] verified) by relay2.tomsk.ru (CommuniGate Pro SMTP 5.1.13) with ESMTPSA id 22938559 for freebsd-questions@freebsd.org; Wed, 28 Dec 2011 20:07:35 +0700 Received: from admin.sibptus.tomsk.ru (sudakov@localhost [127.0.0.1]) by admin.sibptus.tomsk.ru (8.14.5/8.14.5) with ESMTP id pBSD7Y6W023938 for ; Wed, 28 Dec 2011 20:07:35 +0700 (NOVT) (envelope-from vas@mpeks.tomsk.su) Received: (from sudakov@localhost) by admin.sibptus.tomsk.ru (8.14.5/8.14.5/Submit) id pBSD7Yt5023937 for freebsd-questions@freebsd.org; Wed, 28 Dec 2011 20:07:34 +0700 (NOVT) (envelope-from vas@mpeks.tomsk.su) X-Authentication-Warning: admin.sibptus.tomsk.ru: sudakov set sender to vas@mpeks.tomsk.su using -f Date: Wed, 28 Dec 2011 20:07:34 +0700 From: Victor Sudakov To: freebsd-questions@freebsd.org Message-ID: <20111228130734.GA23763@admin.sibptus.tomsk.ru> References: <20111228075422.GA18064@admin.sibptus.tomsk.ru> <4EFAE80D.9040900@my.gd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4EFAE80D.9040900@my.gd> Organization: AO "Svyaztransneft", SibPTUS X-PGP-Key: http://www.livejournal.com/pubkey.bml?user=victor_sudakov X-PGP-Fingerprint: 10E3 1171 1273 E007 C2E9 3532 0DA4 F259 9B5E C634 User-Agent: Mutt/1.5.21 (2010-09-15) Subject: Re: mutual forwarders in ISC BIND X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Dec 2011 13:07:38 -0000 Damien Fleuriot wrote: > > If you're trying to build up a cache to improve performance and response > time, here's your scenario: > > DNS C, forward to DNS A,B for all queries > DNS D, forward to DNS B,A for all queries > > Your cache will start building up and only responses that are not cached > will be taken from your NS A and B servers. Sorry, I fail to see how this is any better than two independent DNS servers. Perhaps a variant like DNS C, forward to DNS A DNS D, forward to DNS A would be close to the goal of cache consolidation. Matthew Seaman wrote: > > If you want to consolidate caches then probably your best bet is to have > fewer, but larger resolvers. A pretty standard server class machine > dedicated to recursive DNS should be easily capable of supporting many > thousands of clients. You are certainly right. > > DNS is not really a fruitful target for reducing traffic volume -- there > really isn't that much of it compared to all other types in any case. > It's also pretty critical to the perceived performance of your networks. > Complicating and slowing down the DNS lookup path just makes everything > look slow. I just wanted the servers to benefit from each other's caches. That could speed up the lookups. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:sudakov@sibptus.tomsk.ru