Re: [DNSOP] howto "internal"

Tony Finch <dot@dotat.at> Wed, 25 July 2018 11:18 UTC

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Date: Wed, 25 Jul 2018 12:18:03 +0100
From: Tony Finch <dot@dotat.at>
To: Grant Taylor <gtaylor=40tnetconsulting.net@dmarc.ietf.org>
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Subject: Re: [DNSOP] howto "internal"
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Grant Taylor <gtaylor=40tnetconsulting.net@dmarc.ietf.org>; wrote:
>
> Is there a best practice around this method of delegating to sub-domain(s)
> that are inaccessible to the public?

I recommend having an empty public view of your private zone, so that
external queries succeed with NXDOMAIN / NODATA. Returning REFUSED for a
private zone causes retries, and not responding at all causes even worse
problems such as EDNS fallback attempts. I haven't tried delegating to
RFC1918 addresses, but that is likely to cause similar weirdness.

Tony.
-- 
f.anthony.n.finch  <dot@dotat.at>;  http://dotat.at/
Bailey: South 3 or 4, becoming cyclonic 5 to 7, occasionally gale 8 for a
time. Slight or moderate, becoming rough or very rough. Rain. Moderate or
poor.