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

Ole Troan <otroan@employees.org> Sun, 27 October 2019 15:03 UTC

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From: Ole Troan <otroan@employees.org>
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Date: Sun, 27 Oct 2019 16:03:38 +0100
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To: Philip Homburg <pch-v6ops-9@u-1.phicoh.com>
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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> On 27 Oct 2019, at 14:42, Philip Homburg <pch-v6ops-9@u-1.phicoh.com> wrote:
> 
> 
>> 
>> This isn't a criticism of what you're suggesting btw. It's an
>> observation that the design philosophy behind SLAAC has intrinsic
>> problems that cannot be resolved without dealing with state and
>> state transfer, and that maybe we need to take a critical look at
>> SLAAC and make potentially difficult decisions about whether or
>> not it's fit for purpose for common deployment situations.
> 
> In this particular case (a CPE rebooting and getting a different prefix from
> the ISP), SLAAC has for the most part what we need.
> 
> The little bit missing is that the CPE should write prefixes advertised using
> SLAAC to persistent storage which allows the CPE to invalidate stale prefixes
> after a reboot.
> 
> Note that we could change SLAAC to allow the lifetime of a prefix to be
> set to zero, instead of having to wait for 2 hours. That might be an
> improvement but requires careful analsysis.

Can you explain how operating a public service should work on this type of network?

Cheers 
Ole