From owner-freebsd-questions Mon Feb 20 14:02:15 1995 Return-Path: questions-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.9/8.6.6) id OAA12767 for questions-outgoing; Mon, 20 Feb 1995 14:02:15 -0800 Received: from halloran-eldar.lcs.mit.edu (halloran-eldar.lcs.mit.edu [18.26.0.159]) by freefall.cdrom.com (8.6.9/8.6.6) with SMTP id OAA12760 for ; Mon, 20 Feb 1995 14:02:11 -0800 Received: by halloran-eldar.lcs.mit.edu; id AA04516; Mon, 20 Feb 1995 17:01:50 -0500 Date: Mon, 20 Feb 1995 17:01:50 -0500 From: Garrett Wollman Message-Id: <9502202201.AA04516@halloran-eldar.lcs.mit.edu> To: terry@cs.weber.edu (Terry Lambert) Cc: jg@euronet.nl (Jan_Guldemond), questions@FreeBSD.org Subject: Re: Domain name In-Reply-To: <9502201728.AA03349@cs.weber.edu> References: <199502201047.LAA16496@mail.euronet.nl> <9502201728.AA03349@cs.weber.edu> Sender: questions-owner@FreeBSD.org Precedence: bulk < The auto-expansion is a result of the cannonical name being looked up > by the program -- basically, it's a feature of your browser. Wrong. It's a feature of the Domain Name System, and has nothing to do with the client program (if any). Here's an example of how it's done around here: wollman@khavrinen(7)$ dig radio.lcs.mit.edu. ; <<>> DiG 2.1 <<>> radio.lcs.mit.edu. ;; res options: init recurs defnam dnsrch ;; got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6 ;; flags: qr rd ra; Ques: 1, Ans: 2, Auth: 6, Addit: 6 ;; QUESTIONS: ;; radio.lcs.mit.edu, type = A, class = IN ;; ANSWERS: radio.lcs.mit.edu. 10045 CNAME halloran-eldar.lcs.mit.edu. halloran-eldar.lcs.mit.edu. 13651 A 18.26.0.159 ;; AUTHORITY RECORDS: [goop deleted] Notice how I asked for a type `A' record (an address), and it came back with TWO answers: one saying ``the canonical name of `radio.lcs.mit.edu.' is `halloran-eldar.lcs.mit.edu.','' and one saying ``oh, and by the way, the address of `halloran-eldar.lcs.mit.edu.' is 18.26.0.159.'' This is built into the DNS; a correct resolver MUST return both the CNAME itself and the type of record originally requested (if the target of the CNAME exists and has such a record). (The actual application we use to manage all of this was developed by my neighbors, the Telemedia Networks & Systems group, and it's called `WebDNS'. As the name implies, it's a Web (forms)-based mechanism for managing the DNS namespace. It replaces a much older system than ran on Symbolics LISPMs.) -GAWollman -- Garrett A. Wollman | Shashish is simple, it's discreet, it's brief. ... wollman@lcs.mit.edu | Shashish is the bonding of hearts in spite of distance. Opinions not those of| It is a bond more powerful than absence. We like people MIT, LCS, ANA, or NSA| who like Shashish. - Claude McKenzie + Florent Vollant