Am Samstag, 13. April 2019, 21:37:19 CEST schrieb Rainer Dorsch: > Thanks, Christian, for your reply.
>
> Am Samstag, 13. April 2019, 19:41:15 CEST schrieb Christian Recktenwald via
>
> Exim-users:
> > On Sat, Apr 13, 2019 at 06:15:33PM +0200, Rainer Dorsch via Exim-users
>
> wrote:
> > > Hi,
> > >
> > > I want to upgrade my server from Debian Jessie to Debian Stretch. I am
> > > afraid that at some time during the upgrade process, there is an invalid
> > > exim configuration and messages get rejected.
> >
> > The whole process is not so much about exim as farmore how the packet
> > management works.
> >
> > (1) If you have your own configuration file in /etc/exim4/exim4.conf
> > there will be no such problem.
> >
> > (2) If you have configured your Exim using the debian packet configuration
> > there also would be no problem.
> >
> > (3) If you are running a modified configuration derived from the debian
> > configuration there might be a glitch but this would be unlikely.
>
> I am running (3), but could attempt to get to a cleaner config during the
> upgrade.
>
> > > Can anybody recommend one of the approaches or even propose something
> > > better...?
> >
> > - in case of (3) you also can:
> > - prevent exim from starting: set "exit 0" as first line in
> >
> > /etc/default/exim4 - create a packet filter rule dropping connections to
> > port 25/tcp - create /etc/exim4/exim4.conf which just makes exim return
> > SMTP error 451
>
> I would feel more comfortable, if I can test the production machine before
> processing "real" mail messages again.
>
> thanks again
> Rainer
