IETF Logo Mail Archive

Re: Running code (Was: I-D Action: draft-ietf-6man-ipv6only-flag-03.txt)

Brian Haberman <brian@innovationslab.net> Fri, 26 October 2018 19:51 UTC

Return-Path: <brian@innovationslab.net>
X-Original-To: ipv6@ietfa.amsl.com
Delivered-To: ipv6@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 85780130DF6 for <ipv6@ietfa.amsl.com>; Fri, 26 Oct 2018 12:51:13 -0700 (PDT)
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, DKIMWL_WL_MED=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=innovationslab-net.20150623.gappssmtp.com
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 rBEGrejGYPeW for <ipv6@ietfa.amsl.com>; Fri, 26 Oct 2018 12:51:11 -0700 (PDT)
Received: from mail-ua1-x92b.google.com (mail-ua1-x92b.google.com [IPv6:2607:f8b0:4864:20::92b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 420A6130DDA for <ipv6@ietf.org>; Fri, 26 Oct 2018 12:51:11 -0700 (PDT)
Received: by mail-ua1-x92b.google.com with SMTP id c18so797761uaq.7 for <ipv6@ietf.org>; Fri, 26 Oct 2018 12:51:11 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=innovationslab-net.20150623.gappssmtp.com; s=20150623; h=subject:to:references:from:openpgp:autocrypt:message-id:date :user-agent:mime-version:in-reply-to; bh=b9p1EPLjwUiK1oHFUPfnfNiXjZiJ2YJ1Rpe2tfxw79o=; b=wMA96x0QJNtN2j8MxQQsejq60r62ge6IMS/vui3LpH89oGmOzksgsZnADR4uWo8VzL XjeGn9+goLFJBQbv+mWcm6w4vxidVhoaMWqD1rSqK3mGl/R02hkZVkotY5S9ArxBqk/t yNAV+Vg9Wptd7IYfSAfJAYgMMRbdFTN3mYnwasJ6XV/J31azDd2iEAvsUZT6ClHS1DIM e+J5agyq8VyVf4BQywbs4BZK14FFxIhDMxyWoQVq8bJEE4aQI9UWqpUiTRMyYQHQGsOt FxYKk8jbX4VljdAN3Cxsk5hRuqAbJzln7d252ZFQgq828g4cp62RyryUkvM5Em+Lnuq3 fcgw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:openpgp:autocrypt :message-id:date:user-agent:mime-version:in-reply-to; bh=b9p1EPLjwUiK1oHFUPfnfNiXjZiJ2YJ1Rpe2tfxw79o=; b=iOyuXd5+n+9GFVeN/f5jdaZHw3AFN3+gjIK4pO7MaTKZBuP3tx207QS6MtCTczw3hT YuhDSr1482sNNti3Y2+QAOxP3Cvjcl+tE63EbMdgqb40rk4V5kHlCBDlcCLWyWdEG64L N8ctcOPHuGfBKvSc/0s4cEMsvbkCHPqhlFF/bdw4135ObccqaNjPJMWN7Ux1VVf9LZM3 SAnJ48yzJmBeJxmpLhGzv8IQRXs0+hUbePT4AfS1u+bg+OpvbFEboCIejFkU0MArMJaw VgzWeE42+AeBbCnzUF/h/tjYQOoBnhpLAjEOwXwUKlxrewOuy5yGEB0rgxfxbCJHlTrh dqng==
X-Gm-Message-State: AGRZ1gJ4gGSvcm7n9H1Bca2Did3r7J+rO6mJzhz3bjWDTzzNSoEHdZL2 Eg/NzgwTDasFs0kijS2XBUjTwVL7GM0=
X-Google-Smtp-Source: AJdET5ezfPeQCu0yb6r3l3HAqkPlXkkTmEhzGSHNblDikWxj+JR7CxZISoBs1pi0hQbTe6bztgKwCg==
X-Received: by 2002:ab0:2444:: with SMTP id g4mr2134572uan.67.1540583470020; Fri, 26 Oct 2018 12:51:10 -0700 (PDT)
Received: from LakeHartwell.local ([2601:154:c001:f99e:e583:9a28:4643:3e08]) by smtp.gmail.com with ESMTPSA id c186sm2743342vke.15.2018.10.26.12.51.08 for <ipv6@ietf.org> (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 26 Oct 2018 12:51:08 -0700 (PDT)
Subject: Re: Running code (Was: I-D Action: draft-ietf-6man-ipv6only-flag-03.txt)
To: ipv6@ietf.org
References: <CAFU7BASO_ByzbanhLKnWV280O_fASd-8W+ujpj3sN6d2-whw2w@mail.gmail.com> <7B48A11D-31DE-443C-B73A-14642EA0A397@jisc.ac.uk> <7526af75-4359-6fc6-e39b-eb94024a04de@si6networks.com> <E1BB1232-C1A2-496A-8157-0682D91EED42@steffann.nl> <5E75F3CA-F1D2-4F4F-9CF7-EEEE59634C1E@gmail.com> <C46C990E-0A4F-4731-8CB1-FD204858935E@consulintel.es> <9B53019C-3506-4C9E-AFCF-D6125FA1A65B@gmail.com> <1157b739-3a66-8d45-e3e1-e5f904dfb9bc@asgard.org> <a00607f9-7ced-f889-b5cb-c2fe16367d73@si6networks.com> <66759b73-0a22-e1a9-49db-21154e8e1267@gmail.com> <37ba23b3-df19-9c2a-bdbe-ba7a99d72d05@si6networks.com> <0d6008a4-337b-2ccb-2d9f-837f786eca65@gmail.com> <bfa4397a-aa7a-1184-4147-4cbfbfd13603@si6networks.com> <8C587906-F0EE-4A61-9046-2BF AC52588C0@isc.org> <E8DE18B5-94FC-411C-A310-E49A382E0079@thehobsons.co.uk> <e0fa8fad1b4249c9af79788323b0a922@boeing.com> <3A03A073-72E2-43A8-90A4-5C29DF445361@thehobsons.co.uk> <27fdbd71125842d888c5136684bf6e7b@boeing.com>
From: Brian Haberman <brian@innovationslab.net>
Openpgp: preference=signencrypt
Autocrypt: addr=brian@innovationslab.net; keydata= xsBNBFu00iABCADmFaK26/LbuN8L6TUCR1yLYikNSL3J69HjO5eWzYtPXii1uyakWg+qOlgZ N8o/Xt3Im/VmcIGH8remMLgczoEYdyw+Fb6/Cu/RMLY5Oq/RsRNdRd1YeUD50n2rdrRoBevD 4Ae0FvQeMF/z/TMUfkTYnzACpalTpSfEWAezVHMCnCXfy493WHO0TVi9l/LbtezILpM/x+W6 WEzcS/sGvtrVzq7Z3CIANr+w26+c9O3TvOmIAAvK4MLdvf1sOkBGS4Z5zvm6W76p0hFvVj5a 2YJq/jc/R52ATjgMdmWK2EYxhBsEQAxr1y/VLiQV6KTxNkwIkAglY9LEeqLOh0ZPXxKrABEB AAHNKUJyaWFuIEhhYmVybWFuIDxicmlhbkBpbm5vdmF0aW9uc2xhYi5uZXQ+wsCTBBMBCAA+ FiEEBfR/AIL0QoN2NSdEmghETMdBF2IFAlu00iICGwMFCQHhM4AFCwkIBwIGFQoJCAsCBBYC AwECHgECF4AACgkQmghETMdBF2J0pwf2Oe7LTP6S81CorhVu4CdgzqtAwnSNUnshCSnZJWzZ 2VBgjYDg8jk8DRprX6mHDFmExelmYItm6EwaNVMYq6/ogIx5KUkJpEtBIjcYDFg5YMpDdkr1 VbYIUion30zK4I6S5FdcaSPhUiYnALsKq64aH3gKsCLMTttE2MyAKin+c3DelQj8FCEmfNPT IQflHcCiNhVhwrtw8PDLXxyTYpfQN5Bw36pe8qe+V6fh3XtrxeutBo4z1ldy2LEs7NRkuwbx o8my3/jWpmtlCLUsFL2kh62AfisKGCzAcW51lu5PccJn3EI80ddhNHkVOOZWzKhNb+MS/ONn hcyxVQ3JsQ/IzsBNBFu00iEBCACxsM1bErsVBrITGDF8HZZGW8qEdFKeIGThYKRZxAP8STvV YKB3ikHJgGyaLproivHG2SD0g2xCtc1b2QlQd+DHe6SpfMpAyQ1Pjt4xP1e2piDAE4CQNSts GbKEQyLhVGF51deC3QtU0KMXP6FkD2oAghQLDAxghOMKffz61yDuGU8Tt0od2AIosohfW2G1 e+oqixB2dwGytDBzvhvWwjw68y1kH/4lDLpN2uIRpa3F+SOwmWh83o0KsQrGr/eZlzpgpcF7 g4pQHRO/3ly98beARAcjHXOlvESY4uGRMXoIHsV5lvNWGobf99Oe6m2tICq99HQkJc09Ww8P Y9ANnYE9ABEBAAHCwHwEGAEIACYWIQQF9H8AgvRCg3Y1J0SaCERMx0EXYgUCW7TSIQIbDAUJ AeEzgAAKCRCaCERMx0EXYnSNB/9pF8uTWk2rWxPQkcSHvYkjUq3KyLAb1TaJ5R1AzT5LHQnM PnqvBwbiKkNspQy126Si7ubUh5TSVvHNQkv8LHF5MQO/AhqC8KlaqFu+8D/BsP2RehS00yBA HbGi9YWT/QqYIAUOYnPz69Nz7A3VbNry3HB1r4kzIA60D9JRDxO6zeI5PKb84K3KwBid3abi Imt/1hGDY+VToGus8a/iecgKKcblg6DOnKBLjXN4OSSwN4FrunYk/TAt2otLChgszgEzP8Zu 4SL2RaHAeWUaxzp29Y5/plHYLkWUzQOhLyBSC0B7pf9QJSiXe44SB6lOHu6036S98DdPkj7B NfjnzeJc
Message-ID: <b47435c0-33ff-a6e5-e860-47afd792b770@innovationslab.net>
Date: Fri, 26 Oct 2018 15:51:07 -0400
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:52.0) Gecko/20100101 Thunderbird/52.9.1
MIME-Version: 1.0
In-Reply-To: <27fdbd71125842d888c5136684bf6e7b@boeing.com>
Content-Type: multipart/signed; micalg="pgp-sha256"; protocol="application/pgp-signature"; boundary="476atk4aBEX7C1837YJ1hCDi893cz5F0f"
Archived-At: <https://mailarchive.ietf.org/arch/msg/ipv6/biv4wch1GKKs92i8PO5XVAfQGdU>
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ipv6/>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 26 Oct 2018 19:51:14 -0000

Hi Bert,

On 10/26/18 2:31 PM, Manfredi (US), Albert E wrote:
> -----Original Message-----
> From: ipv6 <ipv6-bounces@ietf.org> On Behalf Of Simon Hobson
> 
>>> That's one possible hint. Another, perhaps better one, would for the host to see if it has any IPv4 default router available at all.
>>
>> A default (or any) router is not needed for IPv4 to be running and needed - so not really a good hint.
> 
> Actually, I think that is one of the two best hints. The other one is DNS. Of course, any network which is "IPv6-only" can always have IPv4 islands in it, e.g. for that isolated lab. Bring your own switch(es). That's also true with any flag. You're right, an IPv4 router is not essential, but if not there, if no IPv4 addresses show up from the DNS, then you would naturally try IPv6. If you had not tried IPv6 before all of this.

WRT DNS... Are you referring to DNS answers that contain IPv4 addresses
(e.g., A records) or are you referring to DNS answers that arrive via
IPv4 transport? The latter appears to be a viable heuristic, the former
is not. The other aspect that we have to be careful of is the potential
deployment of DNS-over-HTTP(s), which adds a layer (or two) of indirection.

Regards,
Brian

v2.23.0 | Report a Bug | By Email