Backup before double Upgrade Debian 7.0 to 8.1 and Kolab 3.3 to 3.4

[thomas at die-lufts.org]

Hi there,

I am running Kolab 3.3 on a virtualized Debian 7.0 server at the moment. Now I want to upgrade both "parts" of the server: Debian from 7.0 (Wheezy) to 8.1 (Jessie) and Kolab from 3.3 to 3.4. From what I learned reading the mailing list is the best way to upgrade Kolab 3.3 to 3.4 a clean install. That means I need to backup all relevant files and I am searching for information what to back up and how to restore it to the new installation. I found some documentation for Kolab2[1] which seems to be outdated. Does anyone have some information and are there any known caveats?

Kind regards

Thomas

[1] https://wiki.kolab.org/index.php/Backups_for_kolab2