pigeonhole ereject vs reject

[Robert Blayzor]

On Jan 13, 2015, at 7:34 PM, Reindl Harald <h.reindl at thelounge.net> wrote:
> 
> and what would that change?
> nothing if you think about how mail works!
> 
> * the MTA receives the message
> * the MTA confirms with 2xx status code
> * later the delivery server rejects
> * the MTA *must* create a bounce
> 
> just don't reject mails after you confirmed you have received them in the SMTP session and if you don't want a mail after that DISCARD it by consider legal implications - there is nothing between
> 

The above is not entirely true.  You are assuming that your MTA it's sending a 2xx accepting the message immediately before delivery via LMTP completes.  With PRDR (in Exim for example, or without) a 5xx during the LMTP transport should issue a 5xx error back to the sending MTA, not a 2xx.  Therefore, there would be no NDR generated by the receiving system.  The senders MTA would have to generate the NDR, but that's not my problem at that point.  Of course WITHOUT PRDR this is a little bit more of an issue since it would be a rejection for all recipients of the message.

--
Robert
inoc.net!rblayzor
http://inoc.net/