From owner-freebsd-stable@FreeBSD.ORG Thu Jul 17 05:22:53 2008 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 607431065670 for ; Thu, 17 Jul 2008 05:22:53 +0000 (UTC) (envelope-from spork@bway.net) Received: from xena.bway.net (xena.bway.net [216.220.96.26]) by mx1.freebsd.org (Postfix) with ESMTP id 1251C8FC14 for ; Thu, 17 Jul 2008 05:22:52 +0000 (UTC) (envelope-from spork@bway.net) Received: (qmail 81728 invoked by uid 0); 17 Jul 2008 05:22:51 -0000 Received: from unknown (HELO ?192.168.0.220?) (spork@216.220.116.154) by smtp.bway.net with (DHE-RSA-AES256-SHA encrypted) SMTP; 17 Jul 2008 05:22:51 -0000 Date: Thu, 17 Jul 2008 01:22:47 -0400 (EDT) From: Charles Sprickman X-X-Sender: spork@hotlap.local To: Chuck Swiger In-Reply-To: <8DFF6DCD-6619-4251-9944-59CED8DF1B19@mac.com> Message-ID: References: <20080716162042.GA27666@svzserv.kemerovo.su> <487E312E.9090307@infracaninophile.co.uk> <20080717035155.GA81536@svzserv.kemerovo.su> <8DFF6DCD-6619-4251-9944-59CED8DF1B19@mac.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: stable@freebsd.org, Eugene Grosbein Subject: Re: named.conf: query-source address X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 17 Jul 2008 05:22:53 -0000 On Wed, 16 Jul 2008, Chuck Swiger wrote: > On Jul 16, 2008, at 8:51 PM, Eugene Grosbein wrote: >> On Wed, Jul 16, 2008 at 06:34:38PM +0100, Matthew Seaman wrote: >>> The 'query-source' options don't have to be specified: the system >>> will just choose some appropriate address according to the state of >>> the routing table. 'query-source' to set the source /IP/ is really >>> only useful in some specific server configurations with several alias >>> addresses any of which could be used. That's pretty rare really. >> >> Isn't this common to have multiple aliases at an interface? >> Sometimes only one of them should be used for all DNS traffic. > > About the only common reason to set up multiple aliases on an interface is > when you're doing something like hosting multiple SSL webservers on a single > box which actually need to have distinct IPs as a consequence. Other than > that, using public IPs for aliases is usually wasteful of IP address space. I think another common reason is portability of services. When I setup a box, it gets an IP that sticks with that piece of hardware. Each distinct service that I pile onto it then gets it's own IP. This has at least two major advantages that I've found: -If the box dies, it's easy to move any of the services to another box without waiting for DNS changes to propogate. -If one of the services outgrows the box, it's a simple matter to move that service elsewhere, again without playing with DNS. I also will sometimes move services away for a major upgrade of the box. All of this becomes simple when you just bring an alias down on one box and up on another. Next step, putting each service in a jail and moving the jail when needed. > YMMV... On the internets, it always does. :) Charles > Regards, > -- > -Chuck > > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"