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Tagging the Image

Updated Mar 11, 2022 ·

Tags for Versioning​

Tagging allows you to label specific versions of an image, which is crucial for deployment and rollback.

  • Simplifies tracking changes in image versions.
  • Facilitates reverting to previous versions if issues arise.

Tags as Aliases​

Tags serve as aliases for Docker images, helping to identify different builds. If no tag is provided, Docker automatically assigns a "latest" tag.

  • Improves organization by categorizing builds.
  • Makes it easier to reference specific versions when deploying.

Tags Must Be ASCII Character Strings​

Tags can consist of letters, digits, underscores, periods, and dashes, with restrictions on format.

  • Must not start with a period or a dash.
  • Can be up to 128 characters long.

Images Can Have More Than One Tag​

Docker images can be assigned multiple tags, which may appear as separate images but reference the same image ID.

  • Offers flexibility in managing and deploying different versions.
  • Makes it easy to switch between versions without creating duplicates.

Tag Before Pushing the Image to a Container Registry​

It is advisable to tag your image before pushing it to a Docker registry to avoid using random IDs.

  • Ensures images are properly identified in the registry.
  • Helps maintain consistency and clarity in versioning.