On Sun, Mar 30, 2008 at 11:53:37PM -0400, John C Klensin wrote:
It was obvious 20+ years ago that MX processing was broken
as there was no way to say "I don't want email".
First, it may have been obvious to you, but it wasn't obvious to
many of us. In the general case, it still isn't. But you
stated the situation exactly correctly. "MX 0 ." means "I
don't want email". "SRV 0 0 ." doesn't really indicate "no
service", it indicates "please do look for that service here".
actually, it means the DNS admin doesn't want SMTP
connections set to the indicated node.
While it is better than interpreting the lack of a bit in a WKS
record as "no service", it is still nothing more than an attempt
to use the DNS to say "please don't try a mail connection to
Opinions expressed may not even be mine by the time you read them, and
certainly don't reflect those of any other entity (legal or otherwise).
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