IETF Logo Mail Archive

Re: [DNSOP] RFC 1035 vs. mandatory NS at apex?

Tony Finch <dot@dotat.at> Thu, 07 February 2019 14:16 UTC

Return-Path: <dot@dotat.at>
X-Original-To: dnsop@ietfa.amsl.com
Delivered-To: dnsop@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E764A126CB6 for <dnsop@ietfa.amsl.com>; Thu, 7 Feb 2019 06:16:07 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.199
X-Spam-Level:
X-Spam-Status: No, score=-4.199 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id pbuzHIjlTqU3 for <dnsop@ietfa.amsl.com>; Thu, 7 Feb 2019 06:16:05 -0800 (PST)
Received: from ppsw-33.csi.cam.ac.uk (ppsw-33.csi.cam.ac.uk [131.111.8.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id B7BED123FFD for <dnsop@ietf.org>; Thu, 7 Feb 2019 06:16:05 -0800 (PST)
X-Cam-AntiVirus: no malware found
X-Cam-ScannerInfo: http://help.uis.cam.ac.uk/email-scanner-virus
Received: from grey.csi.cam.ac.uk ([131.111.57.57]:53886) by ppsw-33.csi.cam.ac.uk (ppsw.cam.ac.uk [131.111.8.139]:25) with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) id 1grkTC-0006j5-j2 (Exim 4.91) (return-path <dot@dotat.at>); Thu, 07 Feb 2019 14:16:02 +0000
Date: Thu, 7 Feb 2019 14:16:02 +0000
From: Tony Finch <dot@dotat.at>
To: Ted Lemon <mellon@fugue.com>
cc: =?UTF-8?Q?Petr_=C5=A0pa=C4=8Dek?= <petr.spacek@nic.cz>, "dnsop@ietf.org" <dnsop@ietf.org>
In-Reply-To: <F821C2A2-BD6F-41D1-A2D6-3928E783614B@fugue.com>
Message-ID: <alpine.DEB.2.20.1902071407530.18720@grey.csi.cam.ac.uk>
References: <fcd790a2-414b-491e-01e2-9aa92f7b1c4e@nic.cz> <CC75C79C-E5FB-4C91-9453-103E36EDC505@fugue.com> <48a12f46-eee1-823e-a448-8f3b0d973f7d@nic.cz> <F821C2A2-BD6F-41D1-A2D6-3928E783614B@fugue.com>
User-Agent: Alpine 2.20 (DEB 67 2015-01-07)
MIME-Version: 1.0
Content-Type: multipart/mixed; BOUNDARY="1870870841-1654332391-1549548962=:18720"
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/JAS6TREsOh-b2J4rEAND6cds0Og>
Subject: Re: [DNSOP] RFC 1035 vs. mandatory NS at apex?
X-BeenThere: dnsop@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: IETF DNSOP WG mailing list <dnsop.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/dnsop>, <mailto:dnsop-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/dnsop/>
List-Post: <mailto:dnsop@ietf.org>
List-Help: <mailto:dnsop-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/dnsop>, <mailto:dnsop-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 07 Feb 2019 14:16:08 -0000

Ted Lemon <mellon@fugue.com> wrote:
> On Feb 7, 2019, at 7:44 AM, Petr Špaček <petr.spacek@nic.cz> wrote:
> > When looking at it from resolver perspective, what is the resolver
> > supposed to do with query "zone. NS" if there is no authoritative NS set
> > in the zone? Return NOERROR+NODATA?
>
> It should reply with no error and no data.  But this is okay, because
> you never need to ask this question in order to resolve a name.  If you
> are looking up an NS record with intent to use it, it’s going to be in
> the parent zone, where you are looking for a delegation.

But in this scenario things soon go wrong, because RFC 2181 says the
NODATA reply replaces the delegation records in the resolver's cache. This
means that if a client explicitly asks for the NS records of a zone that
lacks them, resolution for other records in the zone will subsequently
fail.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/
Tyne: West, backing south, 5 to 7. Slight or moderate, occasionally rough
later. Showers. Good occasionally moderate.

v2.1.10 | Report a Bug | By Email