Tony Hain wrote:
You should also stop trying to rewrite history by claiming
that something was 'not understood at the time'.
That got me to speed read a few RFCs, 805, 819, 882, 883, 973,
and in 974 I finally found what I wanted:
| It is possible that the list of MXs in the response to the
| query will be empty. This is a special case. If the list
| is empty, mailers should treat it as if it contained one RR,
| an MX RR with a preference value of 0, and a host name of
| REMOTE. (I.e., REMOTE is its only MX). In addition, the
| mailer should do no further processing on the list, but
| should attempt to deliver the message to REMOTE. The idea
| here is that if a domain fails to advertise any information
| about a particular name we will give it the benefit of the
| doubt and attempt delivery.
"special case", "fails to advertise", "benefit of the doubt",
that does not sound like "we still want this 22 years later
also for IPv6".
Earlier MAILA, MAILB, MF, MD, MINFO, MG, etc. proposals were
rather confusing compared with MX, but apparently did not
suggest to try A (?) They just started to use a hierarchical
DNS at this time, and replacing relative names in bang paths
by absolute names was apparently one of the DNS design goals.
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