Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321

Claus Assmann <ietf-smtp@esmtp.org> Sun, 27 September 2020 20:39 UTC

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Date: Sun, 27 Sep 2020 22:39:11 +0200
From: Claus Assmann <ietf-smtp@esmtp.org>
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Subject: Re: [ietf-smtp] EHLO domain validation requirement in RFC 5321
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On Sun, Sep 27, 2020, John C Klensin wrote:

> [1] As handy examples pulled from this thread, 68.166.206.83 and
> 64.147.123.25 apparently have no reverse mapping records at all.

Hmm, not sure why you saying that?

83.206.166.68.in-addr.arpa. 38400 IN	PTR	mailx.courier-mta.com.
25.123.147.64.in-addr.arpa. 3597 IN	PTR	wout2-smtp.messagingengine.com.

DNS problems? Those are sooo much fun to resolve :-(