OwnCloud App Migration
From Univention Wiki
Starting with version 9.1.1 the ownCloud App for UCS is available as a Docker App. New installations automatically use this Docker App.
To update an existing non-Docker ownCloud App to the new Docker ownCloud App a manual migration has to be done. Basically, ownCloud on the server (Docker host) is removed and installed in a new Docker container. Directories with ownCloud data are mapped to the container and the container continues to use the database on the Docker host.
The guide should only be followed if the currently installed owncloud App version is 9.0.6. The following steps are necessary to migrate the non-Docker ownCloud App to Docker:
Check if docker works on the host
Run the following command to verify docker works, before starting the migration:
docker run hello-world
If this test fails, please contact the Univention Support or check the Univention Forum  for more information.
Save ownCloud UCR settings, prepare ownCloud App removal
ucr search --brief ^owncloud > /root/owncloud-ucr-settings.txt cat /etc/owncloudadmin.secret; echo
The admin password should not have changed. Please note, that the last command above shows the password.
Remove ownCloud App
Install ownCloud Docker App
First the code of the ownCloud App is removed. All files and database contents remain in place. The unique internal identifier of the official ownCloud App is 'owncloud82'. This identifier remains unchanged for now, although the version number now differs.
univention-app remove owncloud82 ucr unset appcenter/prudence/docker/owncloud82 du -sh /var/lib/owncloud/* # check how much disk space each user occupies.
univention-app update univention-app install owncloud82=9.1.4-20170427
If you are logged in to the Univention Management Console, it is advised to log out and in again for all modules to register the change.
Verify ownCloud UCS settings in Docker container
univention-app shell owncloud82 ucr search --brief ^owncloud > /root/owncloud-ucr-settings-9.1.4.txt diff -u /root/owncloud-ucr-settings*
Further configurations or modifications of UCR settings have to be done in the container from now on. Use the following command to change into the new ownCloud App container:
univention-app shell owncloud82