It was a bit of a struggle, but in the end, it worked: the Vimexx VPS now also runs Jammy Jellyfish or Ubuntu 22:04 LTS. Assuming a system running under Focal Fossa (Ubuntu 20:04 LTS) you can achieve this in two ways. The first attempts at this did not succeed at all.

The very first attempt was a do-release-upgrade on a system that is otherwise fully in production, so with a well-running Virtualmin. This upgrade did not go well, complained of "broken packages" and aborted. After that, you can continue the upgrade with a regular apt upgrade, but you will run into problems. Plus, for some packages, you have to decide whether to accept the full upgrade or not. With Postfix, Dovecot, and Samba I indicated that I wanted to keep the existing configuration. But if you make mistakes, you will have accidents.

Then the alternative attempt: reinstall the system, so that you have a clean install of Focal. Installing Jammy directly is not possible. Providers of VPSs only give this option if an OS release has proven itself for several years. But you can also get there via a detour. Run the do-release-upgrade over the clean install of Focal so you get a working Jammy and install Virtualmin over it. That works fine if you use the very latest (and beta!) installation script. Once you have a running Virtualmin, you need to restore the backup of the virtual servers. And that went wrong. It must have been mostly ignorance on my part. I had not made the backup in the most convenient way and made a few wrong decisions during the restore.

In desperation, I again made a clean install of Focal, installed Virtualmin, and now restored the backup again. I did that a bit smarter and after a day I was back with a well-running system. Only there was a defect in the database of the Erbenet.NL site. The then last entry in the blog ("Migration, Migration") was not in the backup. And that was quite a long entry, too much to recreate. Fortunately, I had made a system backup with timeshift before the entire adventure, but that did not want to restore at all. In the end, I took this backup apart and copied the entry /var/lib/mysql/erbenet from this backup over the running version, which shows that I don't know enough about how mysql works. From that moment on, no database could be reached and mysql didn't want to do anything anymore. After several hours of googling it finally worked. In such cases, you have to restore the entire folder /var/lib/mysql , because that folder also contains some other files with important data from each database. Anyway, everything worked as it should, in the end.

Had I brought all this nonsense on myself for nothing? After a day of sighing, another attempt was made. Again do-release-upgrade is performed over the system, with Virtualmin running. And apparently, I did it in the most convenient way, because it worked! Oh, the same errors popped up as the first time. Broken packages came in again, and I had to navigate again through choices about Postfix, Dovecot, and Samba, but did all that as carefully as possible and rebooted the system. Then Virtualmin was up and running again, with all databases and with email fully up and running. Only I kept stumbling about reports about Proftpd, but because Samba runs well I never have to do anything with FTP, so Proftpd was removed completely. Virtualmin only grumbled a little bit about that and eventually, I reinstalled it from Virtualmin.

And now the Vx-VPS runs smoothly under Jammy Jellyfish! Hooray and pfffft! Not too early, as far as I'm concerned, because Jammy has already started the first revision. Focal's support won't stop anytime soon, but Ubuntu's focus is now on Jammy, and so is my focus. Serious activity on this front may be delayed until, first, Vimexx releases Jammy for direct installation, and second, Virtualmin simply provides a production version of its install script.