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Re: [DNSOP] ANAME TTL vs GCD

Bjørn Mork <bjorn@mork.no> Tue, 30 October 2018 11:58 UTC

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From: Bjørn Mork <bjorn@mork.no>
To: Tony Finch <dot@dotat.at>
Cc: dnsop@ietf.org
Organization: m
References: <alpine.DEB.2.20.1810301108050.24450@grey.csi.cam.ac.uk>
Date: Tue, 30 Oct 2018 12:57:46 +0100
In-Reply-To: <alpine.DEB.2.20.1810301108050.24450@grey.csi.cam.ac.uk> (Tony Finch's message of "Tue, 30 Oct 2018 11:50:09 +0000")
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Subject: Re: [DNSOP] ANAME TTL vs GCD
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Tony Finch <dot@dotat.at> writes:

> In the first round, the ANAME processor will choose a 30s TTL.
>
> In the second round, 30s later, it will get the target address records
> from the cache with a 15s TTL, so it'll choose a 15s TTL.
>
> The in the third round it'll be back to 30s.
>
> The TTL will flip-flop, and there will be a lot of unwanted zone updates.
>
> This is ugly :-( I'm not sure what the best solution is.

Require DNSSEC for ANAME support and use the Original TTL field from the
RRSIG records.


Bjørn

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