Re: [DNSOP] new ANAME draft: draft-hunt-dnsop-aname-00.txt

Florian Weimer <fweimer@redhat.com> Tue, 11 April 2017 20:36 UTC

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To: Evan Hunt <each@isc.org>
References: <20170407181139.GB66383@isc.org> <cc3bbc7a-3f48-2f7f-a3d9-3f752874fc00@redhat.com> <86FE867E-E1BE-4427-9FB2-D148B3F9C8C2@powerdns.com> <94f7e821-d3a9-8c12-b17f-01d32c383182@redhat.com> <20170411201616.GC3533@isc.org>
Cc: Peter van Dijk <peter.van.dijk@powerdns.com>, dnsop@ietf.org
From: Florian Weimer <fweimer@redhat.com>
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Date: Tue, 11 Apr 2017 22:21:13 +0200
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Subject: Re: [DNSOP] new ANAME draft: draft-hunt-dnsop-aname-00.txt
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On 04/11/2017 10:16 PM, Evan Hunt wrote:
> On Tue, Apr 11, 2017 at 09:11:54PM +0200, Florian Weimer wrote:
>> I don't see how you can detect loops without DNS protocol changes.  The
>> query that comes back will look like a completely fresh query.
>
> We can put a limit on the number of hops that are followed in populating
> the A and AAAA records for the expanded ANAME response.  If that limit is
> exceeded, the ANAME record could be rejected by the auth; either the zone
> wouldn't load or address queries return SERVFAIL.

But what happens when the target server also performs cache filling at 
the same time?

Thanks,
Florian