How To Remove Docker Images, Containers, and Volumes

Docker makes it easy to wrap your applications and services in containers so you can run them anywhere. However, as you work with Docker, it’s also easy to accumulate an excessive number of unused images, containers, and data volumes that clutter the output and consume disk space.

Docker gives you all the tools you need to clean up your system from the command line. This cheat sheet-style guide provides a quick reference to commands that are useful for freeing disk space and keeping your system organized by removing unused Docker images, containers, and volumes.

Purging All Unused or Dangling Images, Containers, Volumes, and Networks

Docker provides a single command that will clean up any resources — images, containers, volumes, and networks — that are dangling (not tagged or associated with a container):

docker system prune

To additionally remove any stopped containers and all unused images (not just dangling images), add the -a flag to the command:

docker system prune -a

Removing Docker Images

Remove one or more specific images

Use the docker images command with the -a flag to locate the ID of the images you want to remove. This will show you every image, including intermediate image layers. When you’ve located the images you want to delete, you can pass their ID or tag to docker rmi:

List:

docker images -a

Remove:

docker rmiImageImage

Remove Dangling Docker Images

Docker images consist of multiple layers. Dangling images are layers that have no relationship to any tagged images. They no longer serve a purpose and consume disk space. They can be located by adding the filter flag -f with a value of dangling=true to the docker images command. When you’re sure you want to delete them, you can use the docker image prune command:

List:

docker images -f dangling=true

Remove:

docker image prune

Removing images according to a pattern

You can find all the images that match a pattern using a combination of docker images and grep. Once you’re satisfied, you can delete them by using awk to pass the IDs to docker rmi. Note that these utilities are not supplied by Docker and are not necessarily available on all systems:

List:

docker images -a |  grep "pattern"

Remove:

docker images -a | grep "pattern" | awk '{print ":"}' | xargs docker rmi

Remove all images

All the Docker images on a system can be listed by adding -a to the docker images command. Once you’re sure you want to delete them all, you can add the -q flag to pass the image ID to docker rmi:

List:

docker system prune

Remove:

docker system prune -a

Removing Containers

Remove one or more specific containers

Use the docker ps command with the -a flag to locate the name or ID of the containers you want to remove:

List:

docker images -a

Remove:

docker rmiImageImage

Remove a container upon exiting

If you know when you’re creating a container that you won’t want to keep it around once you’re done, you can run docker run --rm to automatically delete it when it exits:

Run and Remove:

docker images -f dangling=true

Remove all exited containers

You can locate containers using docker ps -a and filter them by their status: created, restarting, running, paused, or exited. To review the list of exited containers, use the -f flag to filter based on status. When you’ve verified you want to remove those containers, use -q to pass the IDs to the docker rm command:

List:

docker image prune

Remove:

docker images -a |  grep "pattern"

Remove containers using more than one filter

Docker filters can be combined by repeating the filter flag with an additional value. This results in a list of containers that meet either condition. For example, if you want to delete all containers marked as either created (a state which can result when you run a container with an invalid command) or exited, you can use two filters:

List:

docker images -a | grep "pattern" | awk '{print ":"}' | xargs docker rmi

Remove:

docker images -a

Remove containers according to a pattern

You can find all the containers that match a pattern using a combination of docker ps and grep. When you’re satisfied that you have the list you want to delete, you can use awk and xargs to supply the ID to docker rm. Note that these utilities are not supplied by Docker and are not necessarily available on all systems:

List:

docker rmi $(docker images -a -q)

Remove:

docker ps -a

Stop and remove all containers

You can review the containers on your system with docker ps. Adding the -a flag will show all containers. When you’re sure you want to delete them, you can add the -q flag to supply the IDs to the docker stop and docker rm commands:

List:

docker rm ID_or_NameID_or_Name

Remove:

docker run --rm image_name

Removing Volumes

Remove one or more specific volumes

Use the docker volume ls command to locate the volume name or names you wish to delete. Then you can remove one or more volumes with the docker volume rm command:

List:

docker system prune

Remove:

docker system prune -a

Remove dangling volumes

Since the point of volumes is to exist independent from containers, when a container is removed, a volume is not automatically removed at the same time. When a volume exists and is no longer connected to any containers, it’s called a dangling volume.  To locate them to confirm you want to remove them, you can use the docker volume ls command with a filter to limit the results to dangling volumes. When you’re satisfied with the list, you can remove them all with docker volume prune:

List:

docker images -a

Remove:

docker rmiImageImage

Remove a container and its volume

If you create an unnamed volume, it can be deleted at the same time as the container with the -v flag. Note that this only works with unnamed volumes. When the container is successfully removed, its ID is displayed. Note that no reference is made to the removal of the volume. If it is unnamed, it is silently removed from the system. If it is named, it silently stays present.

Remove:

docker images -f dangling=true

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