What are untagged images?

Untagged images are images in the registry that don’t have a tag. You can create untagged images in several ways, for example, by pushing different images consecutively by using the same tag.

Do I have any untagged images?

To find out whether you have any untagged images, list your images by running the ibmcloud cr image-digests command. Untagged images have a hyphen (-) in the Tags column.

Do I need untagged images?

If you have active containers that are running untagged images, you need the untagged images. If you delete untagged images that are in use, you can cause problems with scaling or if you have an automated restart. For this situation to be a problem, you deployed by referencing the image by digest or your image reference might be mutated by a webhook service, for example, Portieris.

How does this change affect me?

If you have many untagged images, you might see an increase in the bill for IBM Cloud Container Registry. You can mitigate this cost by deleting any untagged images that you do not require.

How can I remove untagged images?

You can remove untagged images individually, collectively, or by using retention policies.

• To remove untagged images individually, run the following command, where REPOSITORY is your repository and DIGEST is your digest:

  ibmcloud cr image-rm REPOSITORY@sha256:DIGEST

  For more information, see Deleting images from your private repository.

• To remove untagged images collectively, you can use the ibmcloud cr image-prune-untagged command. For more information, see Clean up your namespaces by deleting untagged images.

• To use retention policies to remove images, including untagged images, see Cleaning up your namespaces in Container Registry.