Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds

Fernando Gont <> Fri, 01 November 2019 03:31 UTC

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To: Ole Troan <>, Philip Homburg <>
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From: Fernando Gont <>
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Date: Fri, 1 Nov 2019 00:28:30 -0300
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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On 28/10/19 06:58, Ole Troan wrote:
> Philip,
>>> I didn't see your answer to:  "I dont know of a single server which
>>> operates that way currently. Can you point to a working example?"
>>> I take it the answer is: "currently none"?
>> Is the question whether people are running services on home networks where
>> the ISP uses flash renumbering?
>> If so, the answer is yes. There are a number of 'dynamic DNS' providers.
>> People use those to keep DNS up-to-date when their public IPv4 address changes.
>> All of this is small scale hobbyist usage (and most likely only IPv4) but
>> it does exist.
> No, the question is if there is any host stack + server software that deals with flash renumbering deployed.
> And that is deployable without coding.
> It's the same question Owen posed for the ISP side, when challenged with how DHCP behaves.
> The point here is that we as the IETF must also consider the end-user here. Not that I don't think ISPs do that too, but so far this debate has largely been on the premise of the opertor with little concern of the consequences for the user.

No, that's in correct. This document was, in fact, triggered by an
operator that does care.

And both here and on the ipv6-ops there have been statements noting that
they have these scenarios in their networks. And not because they don't
care about their users.

Fernando Gont
SI6 Networks
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