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

Ted Lemon <> Mon, 11 November 2019 20:05 UTC

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From: Ted Lemon <>
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Date: Mon, 11 Nov 2019 15:05:16 -0500
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To: Mark Smith <>
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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 Nov 11, 2019, at 2:47 PM, Mark Smith <> wrote:
> Unplanned "flash" renumbering due to a topology change implies an unplanned "flash" topology change. That's going to be a rare event, and ideally shouldn't ever occur, because I think it is a sign that some other planning hasn't been occurring.

It’s not quite as simple as that.   A topological bifurcation (or any similar division) should be pretty easy to manage without flash renumbering, because you can just renumber before you change the topology.   Assuming you have time.  But anything more complicated is going to require the propagation of network routes for each customer to multiple places in the network.   I think this is eminently doable, but it’s not trivial, and I wouldn’t be surprised if it’s not something an operator can easily do with their existing tooling.