From owner-freebsd-questions@FreeBSD.ORG Mon Jul 18 22:02:56 2005 Return-Path: X-Original-To: freebsd-questions@freebsd.org Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 63CB816A41C for ; Mon, 18 Jul 2005 22:02:56 +0000 (GMT) (envelope-from garys@opusnet.com) Received: from opusnet.com (mail.opusnet.com [209.210.200.6]) by mx1.FreeBSD.org (Postfix) with ESMTP id 12AFA43D45 for ; Mon, 18 Jul 2005 22:02:55 +0000 (GMT) (envelope-from garys@opusnet.com) Received: from localhost.localdomain [70.98.247.55] by opusnet.com with ESMTP (SMTPD32-8.05) id A70B1EB3006E; Mon, 18 Jul 2005 15:02:51 -0700 Received: from localhost.localdomain (localhost.localhost [127.0.0.1]) by localhost.localdomain (8.13.3/8.13.3) with ESMTP id j6IM3JvW002157; Mon, 18 Jul 2005 15:03:19 -0700 (PDT) (envelope-from garys@opusnet.com) Received: (from jojo@localhost) by localhost.localdomain (8.13.3/8.13.3/Submit) id j6IM3Ddp002156; Mon, 18 Jul 2005 15:03:13 -0700 (PDT) (envelope-from garys@opusnet.com) To: Aaron Peterson References: <1121706617.14792.3.camel@lmail.bathnetworks.co.uk> <45d750d20507181013a90065f@mail.gmail.com> From: garys@opusnet.com (Gary W. Swearingen) Date: Mon, 18 Jul 2005 15:03:13 -0700 In-Reply-To: <45d750d20507181013a90065f@mail.gmail.com> (Aaron Peterson's message of "Mon, 18 Jul 2005 13:13:45 -0400") Message-ID: User-Agent: Gnus/5.1006 (Gnus v5.10.6) XEmacs/21.4 (Jumbo Shrimp, berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: "freebsd-questions@freebsd.org" Subject: Re: Change of FQDN 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: Mon, 18 Jul 2005 22:02:56 -0000 Aaron Peterson writes: > hostname="www.mydomain.com" Say I have two Ethernet ports and I'd like to be gary.mydomain.com on one and gary2.mydomain.com or gary.mydomain2.com on the other; then what? A computer's domain name is set in several places -- not always the same values. Most commonly they're in DNS servers and /etc/hosts and, of course, the computer's kernel as set by the "hostname" command (eg, using /etc/rc.conf's "hostname" variable). But since there's only one "hostname" setting, which can't always match all the others, it's never made sense to me to set "hostname" to any public Internet domain name. (And I never have, IIRC.) And according to BCP-32, at http://www.rfc-editor.org/rfc/rfc2606.txt, "localhost" is the traditional top-level domain name "pointing to the loop back IP address" (which I think of as the 127/24 network), and it should be used to help keep broken DNS software from using any bogus domain on the Internet except well-known ones like "localhost". Though the "hostname" command allows use of a top-level domain, other software doesn't (eg, "sendmail"), so it seems that a good domain is "something.localhost", where "something" may be "localhost", which might avoid some problems with broken software, or something more creative and maybe assigned uniquely to each of a group of computers. It is not used in the public (or maybe even a private) DNS system, except as an identifier for log files. Am I missing something? It's quite likely. What other software than sendmail needs my single "hostname" and when?