On Wed, Jul 08, 2015 at 08:58:38PM +0000, Rosenbaum, Larry M. wrote:
> > Jul 8 17:46:08 mail postfix/smtp[14519]: 3mRP4H3mJMz373gD: reject:
> > END_OF_DATA from mail.external.org[192.0.2.25]: queue file size limit
> > exceeded; from=<external_sender>, to=<my_user@mydomain>, proto=ESMTP,
> > helo=<mail.external.org>
>
> If the client looks at the SIZE line of the EHLO response, it may determine
> at that point that the message is too big and abort the attempt. In that
> case the server doesn't have any envelope data to log, and might not even
> know why the client gave up.
This is increasingly the most common case. SMTP clients that don't
support "SIZE=<limit>" are rare and getting more so.
--
Viktor.
