nanog mailing list archives

Re: looking for terminology recommendations concerning non-rooted FQDNs


From: Mark Andrews <marka () isc org>
Date: Sun, 24 Feb 2013 00:28:38 +1100


In message <30545475.6952.1361592063875.JavaMail.root () benjamin baylink com>, Ja
y Ashworth writes:
----- Original Message -----
From: "Cutler James R" <james.cutler () consultant com>

A domain name without a terminal dot is a relative domain name.
-- An application requesting name to address translation gets to
decide if a search list is to be used, including the default of dot.

A domain name with a terminal dot is a Fully Qualified Domain Name.
-- An application requesting name to address translation must submit
the name as received to the lookup process.

These definitions have been effective of decades and do not need
additional terminology.
-- Faulty implementations are not an excuse for ever more complex
terminology.

The authoritative document here is, as Joe Abley noted earlier, RFC 1035,
which says, in section 5.1:

"""
Domain names that end in a dot are called absolute, and are taken as 
complete.  Domain names which do not end in a dot are called relative; 
the actual domain name is the concatenation of the relative part with 
an origin specified in a $ORIGIN, $INCLUDE, or as an argument to the
master file loading routine.  A relative name is an error when no
origin is available.
"""

Which applies to domain names in master files.
 
Or, in more Jewish terms: not so much.

And in fact, I don't believe that you *have* a manual API-level choice
as an application as to whether your resolver library will apply a
search list or not: if you specify an absolute name, it won't; if you 
specify a relative name, it will.

Nope: gethostbyname(3) only takes one argument: char *hostname

So the only control you have as app is whether you include the trailing
dot.

On most platforms it isn't the only control.  Not gethostname predates
search lists and even heirachical domain named.
 
(PS: your quoting (or bulleting) protocol is non-standard and non-intuitive)

Cheers,
-- jra


-- 
Jay R. Ashworth                  Baylink                       jra () baylink co
m
Designer                     The Things I Think                       RFC 210
0
Ashworth & Associates     http://baylink.pitas.com         2000 Land Rover DI
I
St Petersburg FL USA               #natog                      +1 727 647 127
4

-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka () isc org


Current thread: