How to tag and remove tag on docker

September 16, 2013

Let's say you already have some images.

$ docker images
REPOSITORY   TAG                                        ID                  CREATED             SIZE
user/foobar  1dee6a0ffae858a796e53aaf88a676f9ccb33165   c4480f1bd5a7        About an hour ago   12.29 kB (virtual 1.625 GB)
user/fizbiz  9c4f77f7388406f5ad3cfbc673e2f1bb27fe3d29   6b9184c7d178        11 hours ago        12.29 kB (virtual 1.299 GB)
...

Then you can tag to any image IDs with tag command.

$ docker tag c4480f1b user/foobar latest
$ docker images
REPOSITORY   TAG                                        ID                  CREATED             SIZE
user/foobar  1dee6a0ffae858a796e53aaf88a676f9ccb33165   c4480f1bd5a7        About an hour ago   12.29 kB (virtual 1.625 GB)
user/foobar  latest                                     c4480f1bd5a7        About an hour ago   12.29 kB (virtual 1.625 GB)
...

If you run from them,

$ docker run user/foobar
or
$ docker run user/foobar:1dee6a0ffae858a796e53aaf88a676f9ccb33165

latest can be ommitted. These two are same.

Also if removing one of them, use rmi subcommand.

$ docker rmi user/foobar:1dee6a0ffae858a796e53aaf88a676f9ccb33165
$ docker images
REPOSITORY   TAG                                        ID                  CREATED             SIZE
user/foobar  latest                                     c4480f1bd5a7        About an hour ago   12.29 kB (virtual 1.625 GB)
user/fizbiz  9c4f77f7388406f5ad3cfbc673e2f1bb27fe3d29   6b9184c7d178        11 hours ago        12.29 kB (virtual 1.299 GB)
...

The help message says rmi removes one or more images, but it removes only a tag in this case that an image are tagged with multiple tags.