Can I upgrade from Ubuntu 20.04 Desktop to Ubuntu 21 (04/10) Server without losing data?

Edit: To clarify I mean to upgrade to either 21.04 or 21.10.

I found this question that is relevant, but the comments on the answers indicate that Ubuntu Desktop either is not uninstalled or that there is a serious risk of unintentionally removing needed packages or of outright bricking the machine. Obviously neither of these is ideal. I wondered if the problems might be resolved if the change were made as part of an upgrade rather than a standalone uninstallation of the desktop capabilities. I have already added most of the server components, and I no longer need the GUI capabilities which are taking up sorely needed space on the hard drive.

Solution 1:

There is no tested and supported path from 20.04 to 21.04 nor to 21.10. There are a lot of hacks of varying quality.

Recommended: The simplest, safest, and fastest path is to back up your data and services, then install 21.10 Server over the older Desktop system.

• The backup is in case you select the wrong option during install; if you select the correct option, then all your data and services will still be there.