Tor Slettnes wrote:
>
> On Apr 6, 2004, at 14:08, Jeremy Harris wrote:
>
>> Is there any way to do the moral equivalent of
>> a recipient verify callout, but with the full
>> actual data?
>
>
> In other words, to attempt the remote SMTP delivery before accepting
> the mail?
>
> Not easily, and not in Exim. Think of the current issues:
>
> - Mail loops (ringing). If the remote host is misconfigured to
> deliver the mail back to you, and is configured to attempt the delivery
> before accepting the message in a manner similar to you, then both
> machines would be "nesting" calls to each other without closing any
> connections, until one runs out of resources.
No worse than mail loops at present, and detected by the same
means: number of received-by: lines.
>
> - If the message has several recipients, some of which are local, then
> rejecting the entire message delivery based on the result of delivering
> to one single remote recient would be misleading. That's what DSN's
> are for.
Indeed. For that case exim would need to accept the data phase
and still generate a bounce. It's still worth doing for the
single-recipient case.
>
> Perhaps the days when you could freely forward all your mail to another
> host is a thing of the past. Ask the person to read his mail directly
> from your server (using e.g. an IMAP client).
No, I don't think refusing to forward is a solution.
Cheers,
Jeremy
