Why docker rmi command makes multiple items deleted?

Question

I am learning docker by reading docker docs. And for the section about docker rmi, I found a confusing example:

An image pulled by digest has no tag associated with it:

$ docker images --digests

REPOSITORY                     TAG       DIGEST                                                                    IMAGE ID        CREATED         SIZE
localhost:5000/test/busybox    <none>    sha256:cbbf2f9a99b47fc460d422812b6a5adff7dfee951d8fa2e4a98caa0382cfbdbf4986bf8c1536    9 weeks ago     2.43 MB

To remove an image using its digest:

$ docker rmi localhost:5000/test/busybox@sha256:cbbf2f9a99b47fc460d422812b6a5adff7dfee951d8fa2e4a98caa0382cfbdbf
Untagged: localhost:5000/test/busybox@sha256:cbbf2f9a99b47fc460d422812b6a5adff7dfee951d8fa2e4a98caa0382cfbdbf
Deleted: 4986bf8c15363d1c5d15512d5266f8777bfba4974ac56e3270e7760f6f0a8125
Deleted: ea13149945cb6b1e746bf28032f02e9b5a793523481a0a18645fc77ad53c4ea2
Deleted: df7546f9f060a2268024c8a230d8639878585defcc1bc6f79d2728a13957871b

For the above example, why are there multiple Deleted after docker rmi? Shouldn't there be only one image being deleted?

score 1 · Accepted Answer · answered Feb 07 '18 at 10:01

Because the command

docker rmi

removes all the layers in each image.

If your image has 23 layers, you will see 23

Deleted

You can see the layers in an image with the command

docker history myimage

Why docker rmi command makes multiple items deleted?

1 Answers1