After the release of the UCS 4.4-2 update, technical problems with the DVD ISO and appliance images of UCS 4.4-2 were discovered that interfere with the operation of some important apps. This prompted us to take them offline until further notice. We continue to make the UCS 4.4-1 images available for download, from which users can then simply upgrade to UCS 4.4-2 without the technical problems. In this blog post I would like to give information about the current status and the background.

The problems are related to the upgrade to Docker Engine 18.09 as part of the UCS 4.4-2 patchlevel release. Systems already installed with UCS 4.4-1 or older will not be affected because the existing Docker configuration is applied automatically.

Systems newly installed with UCS 4.4-2 are come with Docker Engine 18.09 and a default Docker configuration that differs from App Center requirements in important areas (see bug 50295). The docker0 interface in UCS 4.4-2 is configured with the IP address and thus differs from the expected IP address on UCS. As a result, apps such as ownCloud and Nextcloud, which use the database system directly on UCS, cannot reach the database.

For affected systems, a fix is in progress to correct the Docker configuration on newly installed UCS 4.4-2 systems. On new UCS 4.4-2 systems, already installed apps must then be reinstalled. In addition, new DVD ISO and appliance images will be built, which already contain this fix, and made available for download. These changes will be published today or in the next days. We’ll keep you up to date with this blog article.

Update, 01. October 2019, 14:03 CEST: The DVD ISO image has been updated and is available for download. The appliance images are work in progress.

Update, 01. October, 17:00 CEST: The technical bug could be fixed and the UCS DVD ISO image and the virtual UCS 4.4-2 appliances are available again in the download area and can be downloaded there. We are still working on the solution for an update process of already installed UCS 4.4-2 instances that still show the docker error and communicate the solution here.

Update, 11. October, 12:45 CEST: The fix for bug 50295 was released with Errata Update 300 for UCS 4.4-2. Users who freshly installed UCS 4.4-2 with the erroneous ISO or appliance image between 24. September and 01. October can update their UCS system. Afterwards, affected apps must be uninstalled and newly installed.

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  1. Fei Yu

    October 20, 2019 at 13:25

    Rocket.Chat could not be installed in 4.4-2
    The app Is always spinning in hour glass when its invoked in the App Center.

  2. Nico Gulden

    Nico Gulden

    October 21, 2019 at 09:50

    Hello Fei Yu,

    can you please open a thread at Univention Help ( so that we and the community can help you there. Thank you.



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