Hello, in the past years I have purchased and used the ISPConfig manual to create (Apache based) ISPConfig managed multi-server setups. I have perfectly working "clusters" with ISPConfig "orchestrated" web server, DB server, mail server and so on. Now, I have to upgrade those clusters, because some of them are still Ubuntu 18.04 LTS. However, every time I upgrade the O.S. , ISPConfig stops working. The Ubuntu "per se" works perfectly, but ISPConfig totally breaks. Now, I am kind of prepared to the fact that I have to manually upgrade RoundCube and PHPMyAdmin, but I have no idea about how to upgrade ISPConfig in a way that the admin still works, that the changes I apply in the admin actually go into effect (and don't stick "forever"). I have searched Google and this forum for a solution for this, but there's only 1 thread, it's old, not really conclusive and it's about a single machine ISPConfig only. Any kind soul who has done this, could please give me some pointers, possibily some step by step process? Thanks in advance.
upgrade ubuntu as per standard upgrade documentation follow the install tutorial for the ispconfig perfect server tutorial for the new ubuntu version force update ispconfig. go from 18.04 to 20.04. then repeat again from 20.04 to 22.04 once 22.04 is officially supported. for multiserver, upgrade and update the master ispconfig server first. then upgrade and update the other ispconfig servers in whatever order is most convenient for you.
The steps would look something like this, but every OS version to other OS version can require some different special steps of course. But to get an idea of the order: https://www.howtoforge.com/update-the-ispconfig-perfect-server-from-debian-10-to-debian-11/
