Remove installation but keep data? / Web updater problems

Hi there!

I have Nextcloud installed on my Uberspace (meaning I cannot perform sudo commands there). Freshly installed it works fine, but I do not use it at the moment, because I repeatedly run into huge problems after updates via webend.

The first update (from v14 to v15) resulted in the app being corrupted. I could not access the files anymore and the backend alerted about missing files. I could not remove the steps, so it remained broken. Finally, I deleted the database and removed all files from the installation and web folders.

Then I tried another update (from v15 to v16). The update process failed. This happened when the updater wanted to update the database, which stuck. Now I only get a “Update in progress” and cannot access backend anymore.

  1. Is there a way to remove the installation whilst saving the uploaded files?
  2. How can I make sure the web updater does not ruin the installation?