How to use the command 'docker rmi' (with examples)

The docker rmi command is used to remove one or more Docker images. It provides options to force remove images and to remove images without deleting untagged parents.

Use case 1: Show help

Code:

docker rmi

Motivation: The docker rmi command without any arguments displays the help message, which provides information on how to use the command.

Explanation: When the docker rmi is executed without any arguments, it displays the help message which explains the usage of the command and provides additional information about the command.

Example output:

Usage:  docker rmi [OPTIONS] IMAGE [IMAGE...]

Remove one or more images

Options:
  -f, --force      Force removal of the image
      --no-prune   Do not delete untagged parents

Use case 2: Remove one or more images given their names

Code:

docker rmi image1 image2 ...

Motivation: This use case is used when you want to remove multiple images from Docker by specifying their names.

Explanation: By providing the names of Docker images as arguments to the docker rmi command, you can remove those images from your Docker environment.

Example output:

Untagged: image1:latest
Untagged: image2:latest
Deleted: sha256:1234567890abcdef
Deleted: sha256:abcdef9876543210

Use case 3: Force remove an image

Code:

docker rmi --force image

Motivation: Force removing an image allows you to delete the image even if it is referenced by containers or other images.

Explanation: When the --force (or -f) option is used with the docker rmi command, it forcefully removes the specified image, regardless of whether it is being used by any other container or image.

Example output:

Deleted: sha256:1234567890abcdef

Use case 4: Remove an image without deleting untagged parents

Code:

docker rmi --no-prune image

Motivation: This use case is helpful when you want to remove an image without deleting any untagged parent images associated with it.

Explanation: The --no-prune option prevents the deletion of untagged parent images of the specified image. This can be useful if you want to maintain the parent images for future use.

Example output:

Deleted: sha256:1234567890abcdef

Conclusion:

The docker rmi command provides a convenient way to remove Docker images from your environment. The use cases mentioned above cover different scenarios such as showing help, removing multiple images, force removing an image, and removing an image without deleting untagged parents. Familiarize yourself with these use cases to effectively manage your Docker images.