Re: [ietf-smtp] parsing SMTP replies

Keith Moore <moore@network-heretics.com> Thu, 18 March 2021 11:18 UTC

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From: Keith Moore <moore@network-heretics.com>
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Date: Thu, 18 Mar 2021 07:18:21 -0400
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Subject: Re: [ietf-smtp] parsing SMTP replies
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On 3/17/21 10:54 PM, Viktor Dukhovni wrote:

>> On Mar 17, 2021, at 10:39 PM, Keith Moore <moore@network-heretics.com> wrote:
>>
>> It's been a long time but I'm pretty sure I've seen situations in which it made sense for the recipient limit to be 1.   For example: a special-purpose device (e.g. email to fax, email to printer) or a gateway to a dissimilar mail system, or anything for which it makes sense to insist that per-recipient errors get immediately reported to the client.
> That's really the realm of LMTP, final delivery, not relaying.

No, it's not.   I didn't say anything about this being used for final 
delivery.   The point is that there are legitimately SMTP servers that 
potentially accept traffic from the public Internet, that aren't 
full-blown MTAs.

Keith