Re: [v6ops] A broken promise - "You said PD Prefix Valid Lifetime is going to be X" (Re: SLAAC renum: Problem Statement & Operational workarounds)

Richard Patterson <> Mon, 11 November 2019 18:56 UTC

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From: Richard Patterson <>
Date: Mon, 11 Nov 2019 18:55:28 +0000
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To: Ted Lemon <>, " list" <>
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Subject: Re: [v6ops] A broken promise - "You said PD Prefix Valid Lifetime is going to be X" (Re: SLAAC renum: Problem Statement & Operational workarounds)
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On Mon, 11 Nov 2019 at 17:11, Ted Lemon <> wrote:

> Nobody is expecting you to never renumber.   Well, at least I am not. What
> I am talking about here is deliberate, opportunistic renumbering. If your
> topology changes and you have to renumber, so be it. If you can avoid that
> it’s better, and if you can give notice it’s also better. If you can do it
> gracefully with temporary routes, even better. But you shouldn’t be
> renumbering just ‘cuz.

In that case I think we agree, an operator shouldn't intentionally renumber
"just 'cuz".  However the scenarios I mentioned are far from the Operator
going *out of their way* to not support stable prefixes. The question is
just around how stable they are, and once you start having to ask that
question, then shouldn't we be looking at ways to mitigate the impact to an