Lars Kollstedt:
> On Montag, 29. April 2019 16:26:45 CEST Wietse Venema wrote:
> > To really fix this requires some research and field testing.
>
> Hi Wietse,
>
> that's the reason why I also mentioned, the option to only change
> the behavior in case of enforced TLS. By ignoring the disable_esmtp
> option in the case TLS is enforced.
STARTTLS is not the only problem; with disable_esmtp, the ASA breaks
delivery between MTAs that implement CHUNKING (see my quote from the
CISCO website). Replacing one problem with another problem is not good.
Time planning:
1 - Add a disable_chunking workaround, so that CHUNKING does not
break when disable_esmtp is turned off. This would be needed
for Postfix 3.4.
2 - Find out what other Postfix features are enabled by default and
that would break with disable_esmtp turned off. This may be
needed for Postfix 3.4.
2 - Figure out some way to make disable_esmtp context-sensitive,
without making a mess of Postfix. This may happen in Postfix
3.5.
For now your best bet is to turn off disable_esmtp (with
smtp_pix_workaround_maps or smtp_pix_workarounds) and to disable
CHUNKING (with smtp_discard_ehlo_keyword_address_maps or
smtp_discard_ehlo_keywords).
Wietse
