Re: [DNSOP] the root is not special, everybody please stop obsessing over it

Paul Vixie <paul@redbarn.org> Fri, 15 February 2019 16:39 UTC

Return-Path: <paul@redbarn.org>
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 2BA02130FD6 for <dnsop@ietfa.amsl.com>; Fri, 15 Feb 2019 08:39:17 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.901
X-Spam-Level:
X-Spam-Status: No, score=-1.901 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_PASS=-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 Em9EY-L0pwFv for <dnsop@ietfa.amsl.com>; Fri, 15 Feb 2019 08:39:15 -0800 (PST)
Received: from family.redbarn.org (family.redbarn.org [IPv6:2001:559:8000:cd::5]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 62B8B130FC1 for <dnsop@ietf.org>; Fri, 15 Feb 2019 08:39:15 -0800 (PST)
Received: from [IPv6:2001:559:8000:c9:18eb:443:7c1e:38f2] (unknown [IPv6:2001:559:8000:c9:18eb:443:7c1e:38f2]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by family.redbarn.org (Postfix) with ESMTPSA id A5E97892C6; Fri, 15 Feb 2019 16:39:14 +0000 (UTC)
To: Tony Finch <dot@dotat.at>
Cc: IETF DNSOP WG <dnsop@ietf.org>
References: <b45edb5e-1508-0b02-a14c-a5be4ca9c0e6@redbarn.org> <alpine.DEB.2.20.1902150938540.18720@grey.csi.cam.ac.uk>
From: Paul Vixie <paul@redbarn.org>
Message-ID: <0a5283f8-5511-4c04-9d3b-a6611820fc01@redbarn.org>
Date: Fri, 15 Feb 2019 08:39:13 -0800
User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:52.0) Gecko/20100101 PostboxApp/6.1.10
MIME-Version: 1.0
In-Reply-To: <alpine.DEB.2.20.1902150938540.18720@grey.csi.cam.ac.uk>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Archived-At: <https://mailarchive.ietf.org/arch/msg/dnsop/lMCfRM1XemPB8DNDPaz5l-45WJg>
Subject: Re: [DNSOP] the root is not special, everybody please stop obsessing over it
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: Fri, 15 Feb 2019 16:39:17 -0000


Tony Finch wrote on 2019-02-15 01:47:
> ...
> 
> We have local stealth secondary copies of our zones on our recursive
> servers which helps to some extent, except when downstream validators want
> to get the chain of trust. But serve-stale should help.

prefetching or leasing or rrset subscription is expensive when viewed 
from the dns-at-large perspective. we ought to prioritize the 
information we will need most in the event of a network partition. and 
the idea that an operator would have to predict where a partition could 
take place, and add stealth secondaries for the things they know about, 
is wrong in two ways. it's too much work, and never enough benefit.

> I wonder if it's worth having different prefetch logic for infrastructure
> records (NS, DS, glue, etc) to more eagerly keep them warm than leaf
> records.

yes, it obviously is, but only if you intend to use them even if the 
authority for some of your data is at that moment not reachable. so, 
serve-stale and hammer attempt to solve the wrong problem. if you're 
going to use something the way a stealth slave would do, you've got to 
ask the authority's instructions, and be capable of hearing and trusting 
NOTIFY events when that data changes for any reason.

-- 
P Vixie