From owner-freebsd-current@FreeBSD.ORG Tue May 18 00:16:21 2004 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 7915116A4D1 for ; Tue, 18 May 2004 00:16:21 -0700 (PDT) Received: from ares.wolfpond.org (ns1.wolfpond.org [62.212.96.219]) by mx1.FreeBSD.org (Postfix) with ESMTP id 0B71F43D5E for ; Tue, 18 May 2004 00:16:19 -0700 (PDT) (envelope-from ftigeot@wolfpond.org) Received: from aoi.wolfpond.org (aoi.wolfpond.org [IPv6:2001:7a8:24db:1:20c:76ff:feb4:27e1]) by ares.wolfpond.org (8.12.10/8.12.10) with ESMTP id i4I7GFxJ015200; Tue, 18 May 2004 09:16:15 +0200 (CEST) (envelope-from ftigeot@aoi.wolfpond.org) Received: from aoi.wolfpond.org (localhost [127.0.0.1]) by aoi.wolfpond.org (8.12.10/8.12.10) with ESMTP id i4I7GMpJ078393; Tue, 18 May 2004 09:16:22 +0200 (CEST) (envelope-from ftigeot@aoi.wolfpond.org) Received: (from ftigeot@localhost) by aoi.wolfpond.org (8.12.10/8.12.10/Submit) id i4I7GL8v078392; Tue, 18 May 2004 09:16:21 +0200 (CEST) (envelope-from ftigeot) Date: Tue, 18 May 2004 09:16:21 +0200 From: Francois Tigeot To: "Matthew D. Fuller" Message-ID: <20040518071621.GA78346@aoi.wolfpond.org> References: <0cc701c43704$fe189fc0$7890a8c0@dyndns.org> <200405110321.i4B3LFGI073037@bunrab.catwhisker.org> <20040511093634.GA41727@gits.dyndns.org> <200405180814.15854.4711@chello.at> <20040518063753.GB2038@over-yonder.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040518063753.GB2038@over-yonder.net> User-Agent: Mutt/1.4.2.1i cc: Christian Hiris <4711@chello.at> cc: freebsd-current@freebsd.org cc: Cyrille Lefevre Subject: Re: bind timeouts X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 May 2004 07:16:21 -0000 On Tue, May 18, 2004 at 01:37:53AM -0500, Matthew D. Fuller wrote: > On Tue, May 18, 2004 at 08:14:04AM +0200 I heard the voice of > Christian Hiris, and lo! it spake thus: > > > > As far as i know MX records _must_ have an A record. > > RFC1035 states: > MX records cause type A additional section processing for the host > specified by EXCHANGE. The use of MX RRs is explained in detail > in [RFC-974]. > > RFC974 says: > There is one other special case. If the response contains an > answer which is a CNAME RR, it indicates that REMOTE is actually > an alias for some other domain name. The query should be repeated > with the canonical domain name. > > RFC2821 obsoletes 974, but says substantially the same in regards to > CNAME's. So, by the RFC's it's allowed. > > > For me, I think it's a bad practice. But, hey... You're not the only one. RFC 1912 ( Common DNS Operational and Configuration Errors ) states : Don't use CNAMEs in combination with RRs which point to other names like MX, CNAME, PTR and NS. (PTR is an exception if you want to implement classless in-addr delegation.) For example, this is strongly discouraged: podunk.xx. IN MX mailhost mailhost IN CNAME mary mary IN A 1.2.3.4 -- Francois Tigeot