Re: [ietf-smtp] parsing SMTP replies

John C Klensin <john@jck.com> Mon, 22 March 2021 18:23 UTC

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Date: Mon, 22 Mar 2021 14:23:44 -0400
From: John C Klensin <john@jck.com>
To: Ned Freed <ned.freed@mrochek.com>, Laura Atkins <laura@wordtothewise.com>
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Subject: Re: [ietf-smtp] parsing SMTP replies
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--On Monday, March 22, 2021 08:57 -0700 Ned Freed
<ned.freed@mrochek.com> wrote:

>...
> It's somewhat temping to add some sort of "the MXes pointing
> at this server can be rolled up" indicator to the limits
> specification, but since it's not a limit it doesn't really
> fit. If done it needs to be a separate EHLO announcement.
>...

Ned, Laura,

Just a thought, based on little thinking and less information:
Are there any plausible circumstances in which a system might
want to encourage rolling up a few MXs but not very many?  If
so, that would turn it into a limit, rather than requiring a
separate announcement keyword.  I'm having trouble imagining
such a case, so, if the answer is "no", don't bother with a
detailed explanation.   However, because I think there is value
in minimizing the number of announcements, the question seems
worth asking.

    john