Hi John,
At 08:12 PM 15-12-2019, John C Klensin wrote:
First of all, I read John's message too quickly and had
forgotten that the rejection message attributing the problem to
EHLO does not appear until after a RCPT command is sent. So
SM's test is the important one; John's just didn't go far
enough. There are also a number of issues raised by the error
message. The problem condition should not be attributed to RFC
2821; it probably shouldn't refer to the "Helo command" when
EHLO was used; it is, as suggested above, a policy matter and
not a requirement of any IETF protocol specification; and, while
the specification arguably permits it, accepting the EHLO and
then rejecting the mail transaction only after processing the
MAIL and at least one RCPT command is probably at least in bad
taste. Some of those issues suggest changes or clarification
that should be applied when and if RFC 5321 is updated and
replaced. Most of them have been discussed, at length, on the
ietf-smtp list; I assume the others soon will be.
The rejection is for policy reasons. The error text stating that it
is because of a "RFC violation" is incorrect.
None of the above has much of anything to do with the key issue
that I thought
was worth raising on this list. According to the response to
the trouble ticket, the Secretariat was told to block mail
transactions that used IP address literals in the EHLO command.
No matter how pragmatically desirable that may be (see the
ietf-smtp list for a discussion on that topic too), at least as
I read it (and wrote it) RFC 5321 prohibits that rejection,
making the IETF mail servers non-conforming to the standard.
So, again, the first question for this list is whether we are
comfortable with servers run in the IETF's name being
non-conforming to IETF standards. I see objections to that on
It does not look good when a SDO is unable to explain [1] why it is
ignoring its own standard.
Regards,
S. Moonesamy
1. There is an initiative of the Dutch government:
http://r.elandsys.com/r/94862 At first glance, it looks like there
is something wrong with the server which was tested. It takes a
little more effort to interpret the results.
