Re: [DNSOP] Murray Kucherawy's No Objection on draft-ietf-dnsop-nsec3-guidance-08: (with COMMENT)

Vladimír Čunát <> Mon, 16 May 2022 14:15 UTC

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Subject: Re: [DNSOP] Murray Kucherawy's No Objection on draft-ietf-dnsop-nsec3-guidance-08: (with COMMENT)
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On 10/05/2022 21.55, Murray Kucherawy via Datatracker wrote:
> Regarding the SHOULD in Section 3.2, what other action might a resolver
> legitimately return, and why?

Extended errors (RFC8914) generally aren't "mandatory", so they may 
return none.  In practice I also see quite some leeway in which EDE(s) 
to return, because there are more complex cases than matching a single 
one and implementing everything precisely might be very difficult.  (For 
example, one error got encountered and then the resolver retried against 
with a different RRSIG record or asked a different server and got a 
different error or none.)

> Same question for the SHOULD in Section 4.

Here it's a tradeoff, and not all operators/vendors will have exactly 
the same view.  Some are very sensitive about producing "unnecessary" 
resolution errors (SERVFAILs in this case) and are willing to pay by 
(possibly) doing more CPU work, etc.

--Vladimir |