From owner-freebsd-questions  Thu Sep 11 14:02:53 1997
Return-Path: <owner-freebsd-questions>
Received: (from root@localhost)
          by hub.freebsd.org (8.8.7/8.8.7) id OAA17533
          for questions-outgoing; Thu, 11 Sep 1997 14:02:53 -0700 (PDT)
Received: from titan.comco.com (titan.comco.com [198.214.63.11])
          by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id OAA17525;
          Thu, 11 Sep 1997 14:02:48 -0700 (PDT)
Received: (from dougmc@localhost)
	by titan.comco.com (8.8.7/8.8.7) id QAA07103;
	Thu, 11 Sep 1997 16:03:00 -0500 (CDT)
From: Doug McLaren <dougmc@comco.com>
Message-Id: <199709112103.QAA07103@titan.comco.com>
Subject: Re: BIND Question
In-Reply-To: <199709112014.PAA09359@smokey.prismnet.com> from Greg Stringfellow at "Sep 11, 97 03:14:21 pm"
To: greg@smokey.prismnet.com (Greg Stringfellow)
Date: Thu, 11 Sep 1997 16:02:59 -0500 (CDT)
Cc: freebsd-isp@FreeBSD.ORG, freebsd-questions@FreeBSD.ORG
X-Zippy: ..  My vaseline is RUNNING...
X-Random-Excuse: 
	When I got up this morning I took two Ex-Lax in addition to my Prozac.  I can't get off the john, but I feel good about it.
X-Mailer: ELM [version 2.4ME+ PL26 (25)]
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: owner-freebsd-questions@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk

Greg Stringfellow was tellin' me ...

(Hi Greg!)

| I've got a customer who is trying to send mail to a particular location. The
| hostname is "HPISD_ADMIN.HIGHLANDPARK.K12.TX.US". I remember reading
| somewhere about the underscores in a hostname not being valid. But I just
| can't seem  to track it down.

That is indeed correct.  It's probably in the relevant RFC, but I
certainly can't give you a number for it ...

| Now when on my 2.2 FreeBSD machines, I can nslookup that to get:
...
| Non-authoritative answer:
| Name:    HPISD_ADMIN.HIGHLANDPARK.K12.TX.US
| Address:  206.50.19.5
| 
| But if I try to ping it, telnet to it, or even send mail to it I get:
| 
| bash-2.00# ping HPISD_ADMIN.HIGHLANDPARK.K12.TX.US
| ping: unknown host HPISD_ADMIN.HIGHLANDPARK.K12.TX.US

I get the same behavior on my FreeBSD 2.2.2 machine.  Other OS's
appear to be fine with it.

It looks like the resolver libraries under FreeBSD 2.2.2 actually
enforce the `no _' rule.  Seems kind of wierd to do it there, however
- typically the rule of thumb is to be permissive in what you accept,
but restrictive in what you send ...

Addresses without a _ in their hostname work fine -

   % telnet PROXY.HIGHLANDPARK.K12.TX.US
   Trying 206.50.19.120...
   telnet: Unable to connect to remote host: Connection refused
   % telnet HPISD_ADMIN.HIGHLANDPARK.K12.TX.US
   HPISD_ADMIN.HIGHLANDPARK.K12.TX.US: Unknown host

My advice: mail them, tell them that _'s aren't valid in hostnames and
therefore they only work sometimes, and suggest that they change the
_'s to -'s.

-- 
Doug McLaren, dougmc@comco.com
Unsolicited email of a commercial or advertising nature is not welcomed.
"Often, when I am reading a good book, even in the middle of the night, I stop
 and thank my teacher.  That is, I used to, until she got an unlisted number."