Re: [ietf-smtp] DSNs
Sam Varshavchik <mrsam@courier-mta.com> Tue, 28 April 2020 22:50 UTC
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From: Sam Varshavchik <mrsam@courier-mta.com>
To: ietf-smtp@ietf.org
Date: Tue, 28 Apr 2020 18:50:45 -0400
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Subject: Re: [ietf-smtp] DSNs
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John Levine writes: > In article <cone.1588076349.709902.75652.1004@monster.email-scan.com> you > write: > >> In general I agree but there are still situations where an MTA (mine > >> for example) accepts a message intending to forward it somewhere else > >> and then the forward fails. Either send a DSN or drop it on the floor > >> at that point. > > > >Well, yes. You take ownership of that message by the act of forwarding, you > >now own it, from the point of forwarding. If you don't want to disclose the > >forwarded-to address, that's your responsibility, so either set the sender's > >address to <>, or to some other address where you want the bounces to go. > > Huh? If I send a DSN it includes the original delivery address but it > doesn't have to include the forwarded-to address. I'm talking about the forwarding system. Whatever's forwarding the message, it can easily reset the return address to <>, or to some bit bucket. >From that point on, any DSN can be sent normally. It won't go anywhere, and the sender will never see it. For all practical matters, the forwarding system is the end recipient, and would report any success DSN. Hooray, your message was received by mrsam@courier-mta.com. The fact that it gets forwarded to sam.varshavchik@gmail.com by my forwarding script (it's not, this is just as an example) is something that you have any knowledge of. The return address on the forwarded message is not johnl@taugh.com any more, it's nobody@courier-mta.com. Or maybe it's even <>. You have no knowledge of that, either. Since I received the mail, and I decided to forward it, I can change the return address. There is no law that says that I must keep it the same. Either way, since I set up the forwarding: if it breaks and I lose my mail, I only have myself to blame and noone else. Noone else is responsible for my forwarded mail other than myself. But, as far as you're concerned, you sent mail to mrsam@courier-mta.com with NOTIFY=SUCCESS, and you got a DSN stating that fact. That's all you know. Did I get it at this address, or the other one? You'll never know.
- [ietf-smtp] SMTP, DSNs, and enhanced replies (was… John C Klensin
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Hector Santos
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Brandon Long
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … John Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies John R Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Jeremy Harris
- Re: [ietf-smtp] DSNs Claus Assmann
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Jeremy Harris
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John C Klensin
- [ietf-smtp] Variable HELO name, was DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Arnt Gulbrandsen
- Re: [ietf-smtp] Variable HELO name, was DSNs Ned Freed
- Re: [ietf-smtp] Variable HELO name, was DSNs John C Klensin
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Laura Atkins
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Sam Varshavchik