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

Ted Lemon <> Wed, 30 October 2019 21:59 UTC

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From: Ted Lemon <>
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Date: Wed, 30 Oct 2019 17:59:00 -0400
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Cc: "Bernie Volz (volz)" <>, "" <>, IPv6 Operations <>
To: Bud Millwood <>
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Subject: Re: [v6ops] [dhcwg] SLAAC renum: Problem Statement & Operational workarounds
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On Oct 30, 2019, at 5:52 PM, Bud Millwood <> wrote:
> I wonder if introducing suggestions (1) or (2) aren't pushing existing
> clients to expose new bugs they may have? Suggestion (4) seems
> reasonable to me.

Clients that have bugs should be updated.  Routers that aren’t updatable should be binned.   Sites that have massive numbers of non-updatable routers that can’t be updated don’t have to turn the feature on.   I think it’s fine to make this a server configuration parameter.

The benefit to doing this correctly is that it’s arguably already correct.  There are likely routers out there that will already do the right thing when they get a deprecated prefix.   The most likely use case for a deprecated prefix is not that it has a valid lifetime of zero, but that it has a preferred lifetime of zero: a graceful renumbering event.   DHCPv6 should already support graceful renumbering.   This was a design goal.