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

Sander Steffann <sander@steffann.nl> Fri, 01 November 2019 08:23 UTC

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From: Sander Steffann <sander@steffann.nl>
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Date: Fri, 1 Nov 2019 11:22:52 +0300
Cc: Mark Smith <markzzzsmith@gmail.com>, Ole Troan <otroan@employees.org>, v6ops list <v6ops@ietf.org>
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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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Hi,

>> I think Ole observed that this is contrary to what the PD prefix's
>> Valid Lifetime said would be the case. The ISP supplied a PD Prefix
>> with a Valid Lifetime of X seconds, and then broke that promise by
>> abruptly changing addressing before X seconds. ISPs should be expected
>> to live up to their Valid Lifetime promises.
> 
> "Hope" doesn't make networks run properly.

This isn't "Hope", this is breaking promises, and that does break networks. If you can't at least trust that promises are intended to be kept then you have no network at all...

> In any case, as previously noted, there are multiple scenarios that may
> lead to this problem.

Sure, bad things can happen, and there are cases where despite the best intentions you can't keep your promise. But that doesn't mean everybody should go around making promises without even thinking about keeping them…

Cheers,
Sander