Last night I was busy installing software on the Strato-VPS until (too) late. My strategy is first Apache2, Drupal8, and MySQL, and then try to make a website. That works! In these cases, I always start with Webmin, which gives me control over all kinds of settings on the server from a browser. It all works... and very fast!

This morning I wanted to move on quickly, setting up email software. Just log in.... oops... what was my password again? Tried everything, but nothing works. I simply forgot my own password! That's what you get if you keep going until after bedtime!

Wait a minute! Strato offers the server management program Plesk. Give it a try. Damn... doesn't do anything either. Then just call support. I got through to them pretty quickly. They were correct and friendly. But substantively they had no good news.
1) Plesk only works if you let it be installed with the installation. You can add it yourself later, but then you also have to arrange the license yourself. (And it's not free...) 2) Nobody, including Strato, can access your VPS if you don't have a password. Quite reassuring in itself. "Reinstall everything, unfortunately, that's your only solution...".

So I just gave the installation command for Ubuntu 18.04 again, now with Plesk. It took a while... but after half an hour or so it was back online. Since I also had Plesk installed, Apache and MySQL came with it. Installed drupal again and tried to get a website to work. Doesn't work well. I don't like that Plesk, it has no functions á lá webmin and I don't understand it well. Then another installation command for the system, this time without Plesk. Started again, but that doesn't really matter. You just have to wait a while for the reinstallation to complete. Installed Webmin, Apache2, Drupal, and MySQL again. You get PHP 7.2 automatically with the OS. In short, there is plenty to get back to work.

Now trying to migrate the sites of the domain erbenet.nl...

The first strategic decision concerns the layout of the locations of the websites. The vast majority of sites will be built with the Drupal 8 CMS. And then it shows again how smart this choice was for a migration to a VPS. After all, the easiest method by far is to install Drupal 8 fairly centrally and then link any desired website there. Within Drupal, a distinction is then made based on the web address that the user has accessed. In this way, for example, ajna.erbenet.nl contains the same software as sillybutterfly.nl, even though they are two different sites. In Linux, this can be done very easily thanks to the wonderful invention of the symbolic link. For that, you have to be able to work from the command prompt and that is now possible...