Re: [DNSOP] Closing out issues in draft-ietf-dnsop-resolver-priming

Tony Finch <dot@dotat.at> Fri, 16 October 2015 10:04 UTC

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Date: Fri, 16 Oct 2015 11:04:48 +0100
From: Tony Finch <dot@dotat.at>
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Cc: dnsop WG <dnsop@ietf.org>, Paul Hoffman <paul.hoffman@vpnc.org>
Subject: Re: [DNSOP] Closing out issues in draft-ietf-dnsop-resolver-priming
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Mark Andrews <marka@isc.org> wrote:
> In message <8149BC4D-F11E-4E4F-BBB8-C38D865A4184@vpnc.org>, "Paul Hoffman" writ
> es:
> >
> >     If the response packet does not provide for more than 512 octets due
> >     to lack of EDNS0 support, A RRSets SHOULD be given preference over
> >     AAAA RRSets when filling the additional section.
>
> I would recommend that the transport family used to make the query
> should be the determining factor for which additional records are
> dropped.

I was going to make the same point :-)

> >     What to do with payload sizes indicated by
> >     EDNS0 that are smaller than 1024, is open to discussion.

Do the same thing with or without EDNS0.

> >     At the time
> >     of writing, some root name servers will fill the additional section
> >     with all available A RRSets, only adding some AAAA RRSets, when
> >     queried over IPv4 without EDNS0.

They have the same behaviour (prioritize A) when queried on IPv6.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>  http://dotat.at/
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