Re: A common problem with SLAAC in "renumbering" scenarios

Michael Richardson <mcr+ietf@sandelman.ca> Sun, 03 February 2019 20:38 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Nick Hilliard <nick@foobar.org>
cc: "Joel M. Halpern" <jmh@joelhalpern.com>, v6ops list <v6ops@ietf.org>, 6man WG <ipv6@ietf.org>
Subject: Re: A common problem with SLAAC in "renumbering" scenarios
In-reply-to: <ff42613e-30a6-1e11-f512-6e78bcf7ead5@foobar.org>
References: <60fabe4b-fd76-4b35-08d3-09adce43dd71@si6networks.com> <alpine.DEB.2.20.1901311236320.5601@uplift.swm.pp.se> <m1gpCcz-0000FlC@stereo.hq.phicoh.net> <ddd28787-8905-bafd-3546-2ceef436c8b0@si6networks.com> <m1gptWx-0000G3C@stereo.hq.phicoh.net> <69609C58-7205-4519-B17A-4FBC8AE2EA16@employees.org> <ac773bb5-0da8-064b-d46b-3a218b8c9e7a@si6networks.com> <CFAEACC4-BA78-4DF9-AD8A-3EB0790B8000@employees.org> <a4f6742e-f18e-3384-d4cc-06bfab49101f@si6networks.com> <FEFA99C2-4F09-4D8F-8D51-C9D9D7090637@employees.org> <a484d5de-0dce-a41a-928e-785d8d80d05d@si6networks.com> <CAO42Z2xzYQESqqsz4AEE89vx=AhvBEf8Yzyae9o7z1U1XYyarw@mail.gmail.com> <alpine.DEB.2.20.1902031813310.23912@uplift.swm.pp.se> <23b3ffc3-7f01-6d15-ae93-c0e6932d53a6@si6networks.com> <857eef9b-e37d-1e3e-cf7f-ce2122f4d645@joelhalpern.com> <ff42613e-30a6-1e11-f512-6e78bcf7ead5@foobar.org>
Comments: In-reply-to Nick Hilliard <nick@foobar.org> message dated "Sun, 03 Feb 2019 18:53:38 +0000."
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Date: Sun, 03 Feb 2019 15:38:17 -0500
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Nick Hilliard <nick@foobar.org> wrote:
    > Mikael pointed out a related problem that if the cpe is delegated a
    > prefix via dhcp6-pd and splits this across multiple home networks, it
    > needs to do this in a repeatable way so that even if the SP remembers
    > what prefix it previously delegated, the CPE will divvy that up the
    > same way it did before the reboot.

openwrt gets this right.

    > For whatever sets of underlying reasons, this is a real world problem,
    > which indicates that between CPE vendors and provisioning system
    > vendors, there are problems which lead to end user loss of service. The
    > IETF may well be able to offer reasonable guidance here.

I agree, and having a write up of the issues (as simple as you related them),
would be good, as it would give ISPs something to point at when CPE vendors
get it wrong.

--
Michael Richardson <mcr+IETF@sandelman.ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-