Docker - Tag (Tag, push, and pull your image)

About

In the registry, all image addressing is content addressable, referenced by a digest (currently sha256). Tag is the human readable version of it.

A tag ¹⁾ is a string that identifies an image variant with

• a release version (1.0, 1.1)
• and/or other component (ie jdk11, jdk15, …)

Example

In the case of the ubuntu image, there is multiple variants covering Ubuntu 10.04, 12.04, 12.10, 13.04, 13.10 and 14.04. Each variant is identified by a tag and you can refer to a tagged image like so:

ubuntu:14.04

Format

The tag:

• must be valid ASCII
• can contain:
  • lowercase and uppercase letters,
  • digits,
  • underscores,
  • periods,
  • and hyphens.
• can't start with
  • a period
  • or hyphen
• must be no longer than 128 characters.

Default tag name

If you don't specify a tag, command uses latest as default.

Steps

• Tag

• Login to your repository (by default the docker hub)

docker login

• Push

docker push