How-To: Reinstalling an app while cleaning (unsetting) its UCR variables


Occasionally, you might want to reinstall an app from scratch, clearing all its UCR variables for a clean installation. This quick guide helps you back up UCR variables before unsetting them and reinstalling the app.

Let’s assume you want to reinstall the app Keycloak and start anew.


  • 1. Uninstall the app:
    univention-app remove keycloak

  • 2. Find the corresponding UCR variables:
    ucr search --brief keycloak

  • 3. You might see some variables that you should keep anyway, like appcenter/apps/keycloak/...
    So we have to fine-tune our search parameters. In this example the following would be sufficient (notice the ^):
    ucr search --brief ^keycloak

  • 4. IMPORTANT: Please create a backup for the UCR variables:
    ucr search --brief ^keycloak > backup.txt

  • 5. Now that we made sure those variables can be unset, we strip out the values with sed and sort and save the result in a variable:
    x=$(ucr search --brief ^keycloak | sed -e 's|: .*||p' | sort -u)

  • 6. Unset the variables we saved in x :
    ucr unset $x

  • 7. Reinstall the app
    univention-app install keycloak

This topic was automatically closed after 24 hours. New replies are no longer allowed.