On 13/04/19, Rainer Dorsch via Exim-users (exim-users@???) wrote:
> 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
You need to backup all your configuration files, such as those in
/etc/exim4, /etc/mailname and /etc/aliases. (If you are using etckeeper,
take a snapshot or make a tag in your repo.)
Then I suggest two things:
1. run your config on a stretch virtual machine and check all your
directives still work
I seem to remember there were a small slight changes
2. upgrade to stretch exim4 ahead of the rest of your OS
To do that you will need to add stretch to your /etc/apt/sources.list
and alter your /etc/apt/preferences
See
https://jaqque.sbih.org/kplug/apt-pinning.html
Eg: you will need this line in /etc/apt/sources.list, altered for your
region:
deb http://ftp.fr.debian.org/debian/ stretch main contrib
and an preferences file something like this.
Package: *
Pin: release a=jessie
Pin-Priority: 700
Package: *
Pin: release a=stretch
Pin-Priority: 300
(My use of release nicknames might be a bit wrong -- I use
stable/testing/unstable on my laptop, with the highest pin-priority
given to stable).
This means you should be able to safely upgrade to exim4 and
dependencies only ahead of your general upgrade by issuing:
apt-get -t stretch install exim4-daemon-heavy exim4-config
or maybe
apt-get -t stretch install --reinstall exim4-daemon-heavy exim4-config
Caveat emptor! You might want to do a stretch vm upgrade in this manner
first.
Rory