Q&A: Can I Upgrade UCS or Apps From Within the Docker Container?


Can I upgrade UCS or Apps from within the Docker container?



No, this should not be done nor should it be possible. Always use the UCS host mechanism (UMC, univention-app) to update your app.


UCS Docker Image

Some apps use internally a UCS Docker image in version 4.3 to acquire compatibility. So as additional layer they use UCS 4.3 while the host itself is already upgraded to UCS 4.4 for example.

App version

With a new version of the app the underlying UCS Docker might be updated. However, this is something which has not to be done manually (and should not be possible, too).


  • UCS host: Update your host as usually through UMC or univention-upgrade
  • UCS container: The internal UCS 4.3 has a scheduler configured which installs security fixes automatically.
  • App: Use default ways (see UCS host)

So it is expected behaviour to see the Docker container running on UCS 4.3 while the Docker host runs as 4.4.