Hello,
On Sun, Feb 12, 2012 at 02:42, Andy Bennett <andyjpb@???> wrote:
>> For SMTP specifically, the current specification is also quite clear
>> (RFC 5321, section 5.1):
>>
>> "The lookup first attempts to locate an MX record associated with
>> the name. If a CNAME record is found, the resulting name is processed
>> as if it were the initial name. If a non-existent domain error is
>> returned, this situation MUST be reported as an error. If a temporary
>> error is returned, the message MUST be queued and retried later (see
>> Section 4.5.4.1)."
>
> Quite... and lack of any NS servers tends to be treated as a
> non-existent domain.
No, the lack of response from all authoritative nameservers for a
domain is not treated the same way as a "NXDOMAIN" response from one
of them. The former results in the resolver returning a temporary
error.
Regards,
Daniel
From andy@??? Fri Feb 17 08:42:51 2012
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