IETF Logo Mail Archive

Re: [v6ops] draft-ietf-v6ops-slaac-renum and draft-ietf-v6ops-cpe-slaac-renum

Simon Hobson <linux@thehobsons.co.uk> Fri, 22 May 2020 20:41 UTC

Return-Path: <linux@thehobsons.co.uk>
X-Original-To: v6ops@ietfa.amsl.com
Delivered-To: v6ops@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 19B823A0B23 for <v6ops@ietfa.amsl.com>; Fri, 22 May 2020 13:41:18 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.897
X-Spam-Level:
X-Spam-Status: No, score=-1.897 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_NONE=0.001, 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 499iffOpvt86 for <v6ops@ietfa.amsl.com>; Fri, 22 May 2020 13:41:13 -0700 (PDT)
Received: from patsy.thehobsons.co.uk (patsy.thehobsons.co.uk [80.229.10.150]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 2A44A3A0B22 for <v6ops@ietf.org>; Fri, 22 May 2020 13:41:12 -0700 (PDT)
X-Virus-Scanned: Debian amavisd-new at patsy.thehobsons.co.uk
Received: from simons-macbookpro.thehobsons.co.uk (Simons-MacBookPro.thehobsons.co.uk [192.168.137.111]) by patsy.thehobsons.co.uk (Postfix) with ESMTPSA id C0BCC1BC5F for <v6ops@ietf.org>; Fri, 22 May 2020 20:41:05 +0000 (UTC)
Content-Type: text/plain; charset="us-ascii"
Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2104\))
From: Simon Hobson <linux@thehobsons.co.uk>
In-Reply-To: <m1jc9R0-0000I4C@stereo.hq.phicoh.net>
Date: Fri, 22 May 2020 21:41:04 +0100
Content-Transfer-Encoding: quoted-printable
Message-Id: <36271068-A497-47CE-ACAC-D9B6EF2B9CD5@thehobsons.co.uk>
References: <m1jb1gz-0000MZC@stereo.hq.phicoh.net> <8aa3102e-22b1-60ed-2d99-838f3fdf1736@si6networks.com> <m1jbKVd-0000L7C@stereo.hq.phicoh.net> <CAHL_VyDWYz=hUTZ+RDZ0JuF-KCsh5HBsM1pFFy3FqtL6pC_hCw@mail.gmail.com> <m1jbRI7-0000LCC@stereo.hq.phicoh.net> <CAHL_VyA23QJzgTy_nauxmjPM4PJT00YC451QL+s6d3dMomkX5Q@mail.gmail.com> <m1jc9R0-0000I4C@stereo.hq.phicoh.net>
To: v6ops list <v6ops@ietf.org>
X-Mailer: Apple Mail (2.2104)
Archived-At: <https://mailarchive.ietf.org/arch/msg/v6ops/Vs_Ohq9wyYqH7YECxCGkVCRXO54>
Subject: Re: [v6ops] draft-ietf-v6ops-slaac-renum and draft-ietf-v6ops-cpe-slaac-renum
X-BeenThere: v6ops@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: v6ops discussion list <v6ops.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/v6ops>, <mailto:v6ops-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/v6ops/>
List-Post: <mailto:v6ops@ietf.org>
List-Help: <mailto:v6ops-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/v6ops>, <mailto:v6ops-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 22 May 2020 20:41:19 -0000

Philip Homburg <pch-v6ops-9@u-1.phicoh.com> wrote:
> 

> In any more complex setup where some servers are used both internally
> and externally, there is a good chance that even internally the server is
> referenced using a public DNS name.
> 
> So if the internet connection goes down and the static prefix is no longer
> available due to short lifetimes, then internal connections suffer.

Riiight.
So the network admin has built a network using "consumer grade" or ISP supplied CPE, using default configuration.
Split horizon DNS is not hard, that would deal with it one way by using local addressing internally - just like most people tend to do with IPv4 and NAT already.
Or the network admin could simply statically configure the RAs - so they are not dependent on the WAN link(s) being up.

So the answer to that corner case is simply "properly build your network". Personally I think trying to cater for all use cases, so as to allow a corporate level network to be built without any router config (or, it seems, admin skills), is a road to a massively over-complicated spec that makes it harder rather than easier to build "non-trivial" networks.

Just my 2d worth.

Simon

v2.23.0 | Report a Bug | By Email