Docker and CI/CD · Middle · Question 14 of 75

What are `<none>:<none>` (dangling) images?

✓Correct answer: Old images whose tag moved to a newer build
2Images pulled from a registry without a name
3Images that failed to build halfway through

Explanation

Rebuilding my-app:latest moves the tag and leaves the previous image untagged. docker image prune removes them.

Further reading

Docker Docs: docker image tag ↗

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