Hector Santos wrote:
The different here from what I am reading is that there seems to be this
notion that the DNS resolver is always independent from the SMTP and its
results drive the SMTP client - i.e, the SMTP client is not in the
picture. I don't believe that concept can be presumed to be always true.
Clarification because DNS results always drives an SMTP client :-)
What I meant is that a MX query returning NO RECORDS is what drives the
SMTP to consider using a Implicit MX concept.
If the resolver always return a MX query result, then the SMTP client
will never have any control here. I don't think using the zero
preference is a reliable indicator to represent a raw A record for the
domain.
--
Sincerely
Hector Santos, CTO
http://www.santronics.com
http://santronics.blogspot.com