Re: [DNSOP] WGLC for draft-ietf-dnsop-let-localhost-be-localhost-02

Andrew Sullivan <> Mon, 29 January 2018 17:14 UTC

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From: Andrew Sullivan <>
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Subject: Re: [DNSOP] WGLC for draft-ietf-dnsop-let-localhost-be-localhost-02
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On Fri, Jan 26, 2018 at 05:32:33PM +0100, Petr Špaček wrote:
> I personally agree with the doc, it makes sense to me, and I do not
> believe that its wording prevent anyone from adding knobs they want.
> Software in the end will do whatever its developers wanted, which might
> include knob to override any part of spec.

The purpose of RFC 2119 language is not to make people feel better or
to provide the imaginary benefit of a stick with which to beat people
for non-conformance.  The purpose is to maximise reliable
interoperation, where "reliable" is interpreted generously to include
concern for security and privacy, and "interoperation" is interpreted
generously to include avoidance of anti-patterns in design and
deployment choices.

So the problem here is that, if people start adding local
configurations to override the proposed update to "MUST", the goals of
the document won't be realised anyway.  If on the other hand we
understand 2119 language correctly and apply it rigorously, the
failure to capture localhost at the local boundary will already be
understood as a problem (regardless of what the mechanism is by which
one gets there -- the BSD approach would be as good as any other).

Best regards,


Andrew Sullivan