After 12/29/25 unreferenced layers in GitLab Registry will be automatically deleted

Posted: 2025-12-07 17:24:08   Expiration: 2026-01-10 17:24:08

The DoIT GitLab Container Registry (registry.doit.wisc.edu) will be upgraded during a 10PM - midnight maintenance window on Monday, 12/29/25. After this upgrade, automatic garbage collection will delete unreferenced layers every 24 hours.

Uncommon but possible impact

The upgrade will require no action and create no disruption for the vast majority who use the GitLab Container Registry.  

It's possible that in specific cases, a container sourced from the registry could fail to run, because it depended on a layer unreferenced by any tagged container.  This is not a common situation, since an unreferenced layer by definition should not belong to a tagged container that a user tries to run.  However, edge cases are possible.

In these cases, an alternate version of the same container may run just fine, depending on its layer composition.  In the worst scenario, a user would need to push a new, tagged version of the container to the registry to avoid problems in the future.  

New Features

The next generation GitLab Registry will provide new features immediately, and GitLab will enhance it further with ongoing development.  

If you have any questions or concerns, please feel free to contact the Shared Tools team by emailing help@doit.wisc.edu. 

Sincerely,

The DoIT Shared Tools Team

-- Shared Tools: Benjamin Sousa