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

Ted Lemon <> Wed, 30 October 2019 13:51 UTC

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From: Ted Lemon <>
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Date: Wed, 30 Oct 2019 09:51:06 -0400
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Cc: Timothy Winters <>, IPv6 Operations <>
To: "Bernie Volz (volz)" <>
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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On Oct 30, 2019, at 9:24 AM, Bernie Volz (volz) <> wrote:
> When a CPE boots and does a Solicit / Request, it could include a new option that tells the DHCP server that it has no storage and therefore no knowledge of any “past” leases. The DHCP server in this case could include any “old” leases it still has a record of (i.e., that have not expired but are no longer “valid” in terms of the configuration because of renumbering or other conditions) with 0 lifetimes. That would allow a rebooting CPE to learn old delegated prefixes that it might have advertised to its clients and initiate deprecation of these prefixes (and any addresses generated from them).

I don’t see any reason why this should not just be the default behavior.