How to remove old and unused Docker images - docker

Question

When running Docker for a long time, there are a lot of images in system. How can I remove all unused Docker images at once safety to free up the storage?
In addition, I also want to remove images pulled months ago, which have the correct TAG.
So, I'm not asking for removing untagged images only. I'm searching for a way to remove general unused images, which includes both untagged and other images such as pulled months ago with correct TAG.

Answer 1

(original answer see below)
Update Sept. 2016: Docker 1.13: PR 26108 and commit 86de7c0 introduce a few new commands to help facilitate visualizing how much space the docker daemon data is taking on disk and allowing for easily cleaning up "unneeded" excess.
docker system prune will delete ALL dangling data (i.e. In order: containers stopped, volumes without containers and images with no containers). Even unused data, with -a option.
You also have:
docker container prune
docker image prune
docker network prune
docker volume prune
For unused images, use docker image prune -a (for removing dangling and ununsed images).
Warning: 'unused' means "images not referenced by any container": be careful before using -a.
As illustrated in A L's answer, docker system prune --all will remove all unused images not just dangling ones... which can be a bit too much.
Combining docker xxx prune with the --filter option can be a great way to limit the pruning (docker SDK API 1.28 minimum, so docker 17.04+)
The currently supported filters are:
until (<timestamp>) - only remove containers, images, and networks created before given timestamp
label (label=<key>, label=<key>=<value>, label!=<key>, or label!=<key>=<value>) - only remove containers, images, networks, and volumes with (or without, in case label!=... is used) the specified labels.
See "Prune images" for an example.
Warning: there is no "preview" or "--dry-run" option for those docker xxx prune commands.
This is requested with moby/moby issue 30623 since 2017, but seems tricky to be implemented (Aug. 2022)
Having a more representative overview of what will be pruned will be quite complicated, for various reasons;
race conditions (can be resolved by documenting the limitations);
A container/image/volume/network may not be in use at the time that "dry run" is used, but may be in use the moment the actual prune is executed (or vice-versa), so dry run will always be an "approximation" of what will be pruned.
the more difficult part is due to how objects (containers, images, networks etc.) depend on each other.
For example, an image can be deleted if it no longer has references to it (no more tags, no more containers using it); this is the reason that docker system prune deletes objects in a specific order (first remove all unused containers, then remove unused images).
In order to replicate the same flow for "dry-run", it will be needed to temporarily construct representation of all objects and where they're referenced based on that (basically; duplicate all reference-counters, and then remove references from that "shadow" representation).
Finally; with the work being done on integrating the containerd snapshotter (image and layer store), things may change more;
For example, images can now be multi-arch, and (to be discussed), "pruning" could remove unused variants (architectures) from an image to clean up space, which brings another dimension to calculating "what can be removed".
Original answer (Sep. 2016)
I usually do:
docker rmi $(docker images --filter "dangling=true" -q --no-trunc)
I have an [alias for removing those dangling images: drmi]13
The dangling=true filter finds unused images
That way, any intermediate image no longer referenced by a labelled image is removed.
I do the same first for exited processes (containers)
alias drmae='docker rm $(docker ps -qa --no-trunc --filter "status=exited")'
As haridsv points out in the comments:
Technically, you should first clean up containers before cleaning up images, as this will catch more dangling images and less errors.
Jess Frazelle (jfrazelle) has the bashrc function:
dcleanup(){
docker rm -v $(docker ps --filter status=exited -q 2>/dev/null) 2>/dev/null
docker rmi $(docker images --filter dangling=true -q 2>/dev/null) 2>/dev/null
}
To remove old images, and not just "unreferenced-dangling" images, you can consider docker-gc:
A simple Docker container and image garbage collection script.
Containers that exited more than an hour ago are removed.
Images that don't belong to any remaining container after that are removed.

Answer 2

Update the second (2017-07-08)
Refer (again) to VonC, using the even more recent system prune. The impatient can skip the prompt with the -f, --force option:
docker system prune -f
The impatient and reckless can additionally remove "unused images not just the dangling ones" with the -a, --all option:
docker system prune -af
https://docs.docker.com/engine/reference/commandline/system_prune/
Update
Refer to VonC's answer which uses the recently added prune commands. Here is the corresponding shell alias convenience:
alias docker-clean=' \
docker container prune -f ; \
docker image prune -f ; \
docker network prune -f ; \
docker volume prune -f '
Old answer
Delete stopped (exited) containers:
$ docker ps --no-trunc -aqf "status=exited" | xargs docker rm
Delete unused (dangling) images:
$ docker images --no-trunc -aqf "dangling=true" | xargs docker rmi
If you have exercised extreme caution with regard to irrevocable data loss, then you can delete unused (dangling) volumes (v1.9 and up):
$ docker volume ls -qf "dangling=true" | xargs docker volume rm
Here they are in a convenient shell alias:
alias docker-clean=' \
docker ps --no-trunc -aqf "status=exited" | xargs docker rm ; \
docker images --no-trunc -aqf "dangling=true" | xargs docker rmi ; \
docker volume ls -qf "dangling=true" | xargs docker volume rm'
References
docker ps -f
docker rm
docker images -f
docker rmi
Docker v1.9.0 release notes
docker volume ls
docker volume rm

Answer 3

The other answers are great, specifically:
docker system prune # doesn't clean out old images
docker system prune --all # cleans out too much
But I needed something in the middle of the two commands so the filter option was what I needed:
docker image prune --all --filter "until=4320h" # delete images older than 6 months ago; 4320h = 24 hour/day * 30 days/month * 6 months
For reference: https://docs.docker.com/config/pruning/#prune-images

Answer 4

To remove old tagged images that are more than a month old:
$ docker images --no-trunc --format '{{.ID}} {{.CreatedSince}}' \
| grep ' months' | awk '{ print $1 }' \
| xargs --no-run-if-empty docker rmi
Note that it'll fail to remove images that are used by a container, referenced in a repository, has dependent child images... which is probably what you want. Else just add -f flag.
Example of /etc/cron.daily/docker-gc script:
#!/bin/sh -e
# Delete all stopped containers (including data-only containers).
docker ps -a -q --no-trunc --filter "status=exited" | xargs --no-run-if-empty docker rm -v
# Delete all tagged images more than a month old
# (will fail to remove images still used).
docker images --no-trunc --format '{{.ID}} {{.CreatedSince}}' | grep ' months' | awk '{ print $1 }' | xargs --no-run-if-empty docker rmi || true
# Delete all 'untagged/dangling' (<none>) images
# Those are used for Docker caching mechanism.
docker images -q --no-trunc --filter dangling=true | xargs --no-run-if-empty docker rmi
# Delete all dangling volumes.
docker volume ls -qf dangling=true | xargs --no-run-if-empty docker volume rm

Answer 5

According to the doc, the following command will delete images older than 48 hours.
$ docker image prune --all --filter until=48h

Answer 6

Assuming you have Docker 1.13 or higher you can just use the prune commands. For your question specifically for removing old images, you want the first one.
# Remove unused images
docker image prune
# Remove stopped containers.
docker container prune
# Remove unused volumes
docker volume prune
# Remove unused networks
docker network prune
# Command to run all prunes:
docker system prune
I would recommend not getting used to using the docker system prune command. I reckon users will accidentally remove things they don't mean to. Personally, I'm going to mainly be using the docker image prune and docker container prune commands.

Answer 7

Until now (Docker version 1.12) we are using the following command to delete all the running containers. Also, if we want to delete the volumes, we can do that manually using its respective tag -v in the following command.
Delete all Exited Containers
docker rm $(docker ps -q -f status=exited)
Delete all Stopped Containers
docker rm $(docker ps -a -q)
Delete All Running and Stopped Containers
docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)
Remove all containers, without any criteria
docker container rm $(docker container ps -aq)
But, in version 1.13 and above, for complete system and cleanup, we can directly user the following command:
docker system prune
All unused containers, images, networks and volumes will get deleted. We can also do this using the following commands that clean up the individual components:
docker container prune
docker image prune
docker network prune
docker volume prune

Answer 8

This worked for me:
docker rmi $(docker images | grep "^<none>" | awk "{print $3}")

Answer 9

I recently wrote a script to solve this on one of my servers:
#!/bin/bash
# Remove all the dangling images
DANGLING_IMAGES=$(docker images -qf "dangling=true")
if [[ -n $DANGLING_IMAGES ]]; then
docker rmi "$DANGLING_IMAGES"
fi
# Get all the images currently in use
USED_IMAGES=($( \
docker ps -a --format '{{.Image}}' | \
sort -u | \
uniq | \
awk -F ':' '$2{print $1":"$2}!$2{print $1":latest"}' \
))
# Get all the images currently available
ALL_IMAGES=($( \
docker images --format '{{.Repository}}:{{.Tag}}' | \
sort -u \
))
# Remove the unused images
for i in "${ALL_IMAGES[#]}"; do
UNUSED=true
for j in "${USED_IMAGES[#]}"; do
if [[ "$i" == "$j" ]]; then
UNUSED=false
fi
done
if [[ "$UNUSED" == true ]]; then
docker rmi "$i"
fi
done

Answer 10

Here is a script to clean up Docker images and reclaim the space.
#!/bin/bash -x
## Removing stopped container
docker ps -a | grep Exited | awk '{print $1}' | xargs docker rm
## If you do not want to remove all container you can have filter for days and weeks old like below
#docker ps -a | grep Exited | grep "days ago" | awk '{print $1}' | xargs docker rm
#docker ps -a | grep Exited | grep "weeks ago" | awk '{print $1}' | xargs docker rm
## Removing Dangling images
## There are the layers images which are being created during building a Docker image. This is a great way to recover the spaces used by old and unused layers.
docker rmi $(docker images -f "dangling=true" -q)
## Removing images of perticular pattern For example
## Here I am removing images which has a SNAPSHOT with it.
docker rmi $(docker images | grep SNAPSHOT | awk '{print $3}')
## Removing weeks old images
docker images | grep "weeks ago" | awk '{print $3}' | xargs docker rmi
## Similarly you can remove days, months old images too.
Original script
https://github.com/vishalvsh1/docker-image-cleanup
Usually Docker keeps all temporary files related to image building and layers at
/var/lib/docker
This path is local to the system, usually at THE root partition, "/".
You can mount a bigger disk space and move the content of /var/lib/docker to the new mount location and make a symbolic link.
This way, even if Docker images occupy space, it will not affect your system as it will be using some other mount location.
Original post: Manage Docker images on local disk

Answer 11

I'm using this command:
export BEFORE_DATETIME=$(date --date='10 weeks ago' +"%Y-%m-%dT%H:%M:%S.%NZ")
docker images -q | while read IMAGE_ID; do
export IMAGE_CTIME=$(docker inspect --format='{{.Created}}' --type=image ${IMAGE_ID})
if [[ "${BEFORE_DATETIME}" > "${IMAGE_CTIME}" ]]; then
echo "Removing ${IMAGE_ID}, ${BEFORE_DATETIME} is earlier then ${IMAGE_CTIME}"
docker rmi -f ${IMAGE_ID};
fi;
done
This will remove all images whose creation time is greater than 10 weeks ago.

Answer 12

If you want to remove images pulled X months ago, you can try the below example which remove images created three months ago:
three_months_old_images=`docker images | grep -vi "<none>" | tr -s ' ' | cut -d" " -f3,4,5,6 | grep "3 months ago" | cut -d" " -f1`
docker rmi $three_months_old_images

Answer 13

To prune all images and volumes as well
docker system prune -af --volumes

Answer 14

docker system prune -a
(You'll be asked to confirm the command. Use -f to force run, if you know what you're doing.)

Answer 15

#VonC already gave a very nice answer, but for completeness here is a little script I have been using---and which also nukes any errand Docker processes should you have some:
#!/bin/bash
imgs=$(docker images | awk '/<none>/ { print $3 }')
if [ "${imgs}" != "" ]; then
echo docker rmi ${imgs}
docker rmi ${imgs}
else
echo "No images to remove"
fi
procs=$(docker ps -a -q --no-trunc)
if [ "${procs}" != "" ]; then
echo docker rm ${procs}
docker rm ${procs}
else
echo "No processes to purge"
fi

Answer 16

To remove tagged images which have not container running, you will have to use a little script:
#!/bin/bash
# remove not running containers
docker rm $(docker ps -f "status=exited" -q)
declare -A used_images
# collect images which has running container
for image in $(docker ps | awk 'NR>1 {print $2;}'); do
id=$(docker inspect --format="{{.Id}}" $image);
used_images[$id]=$image;
done
# loop over images, delete those without a container
for id in $(docker images --no-trunc -q); do
if [ -z ${used_images[$id]} ]; then
echo "images is NOT in use: $id"
docker rmi $id
else
echo "images is in use: ${used_images[$id]}"
fi
done

Answer 17

Remove old containers weeks ago.
docker rm $(docker ps -a | grep "weeks" | awk '{ print $1; }')
Remove old images weeks ago. Be careful. This will remove base images which was created weeks ago but which your new images might be using.
docker rmi $(docker images | grep 'weeks' | awk '{ print $3; }')

Answer 18

How to remove a tagged image
docker rmi the tag first
docker rmi the image.
# that can be done in one docker rmi call e.g.: #
docker rmi <repo:tag> <imageid>
(this works Nov 2016, Docker version 1.12.2)
e.g.
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
usrxx/the-application 16112805 011fd5bf45a2 12 hours ago 5.753 GB
usryy/the-application vx.xx.xx 5af809583b9c 3 days ago 5.743 GB
usrzz/the-application vx.xx.xx eef00ce9b81f 10 days ago 5.747 GB
usrAA/the-application vx.xx.xx 422ba91c71bb 3 weeks ago 5.722 GB
usrBB/the-application v1.00.18 a877aec95006 3 months ago 5.589 GB
$ docker rmi usrxx/the-application:16112805 && docker rmi 011fd5bf45a2
$ docker rmi usryy/the-application:vx.xx.xx && docker rmi 5af809583b9c
$ docker rmi usrzz/the-application:vx.xx.xx eef00ce9b81f
$ docker rmi usrAA/the-application:vx.xx.xx 422ba91c71bb
$ docker rmi usrBB/the-application:v1.00.18 a877aec95006
e.g. Scripted remove anything older than 2 weeks.
IMAGESINFO=$(docker images --no-trunc --format '{{.ID}} {{.Repository}} {{.Tag}} {{.CreatedSince}}' |grep -E " (weeks|months|years)")
TAGS=$(echo "$IMAGESINFO" | awk '{ print $2 ":" $3 }' )
IDS=$(echo "$IMAGESINFO" | awk '{ print $1 }' )
echo remove old images TAGS=$TAGS IDS=$IDS
for t in $TAGS; do docker rmi $t; done
for i in $IDS; do docker rmi $i; done

Answer 19

docker rm $(docker ps -faq)
docker rmi $(docker ps -faq)
-f force
-a all
-q in the mode

Answer 20

First, run docker images to see list of images and copy IMAGE HASH ID into clipboard.
Run docker rmi -f <Image>
Remember option -f is force deleting.

Answer 21

Occasionally I have run into issues where Docker will allocate and continue to use disk space, even when the space is not allocated to any particular image or existing container. The latest way I generated this issue accidentally was using "docker-engine" centos build instead of "docker" in RHEL 7.1. What seems to happen is sometimes the container clean-ups are not completed successfully and then the space is never reused. When the 80GB drive I allocated as / was filled with /var/lib/docker files I had to come up with a creative way to resolve the issue.
Here is what I came up with. First to resolve the disk full error:
Stop docker: systemctl stop docker
Allocated a new drive mounted as say /mnt/docker .
Move all the files in /var/lib/docker to /mnt/docker . I used the command:
rsync -aPHSx --remove-source-files /var/lib/docker/ /mnt/docker/
Mount the new drive to /var/lib/docker.
At this point I no longer had a disk full error, but I was still wasting a huge amount of space. The next steps are to take care of that.
Start Docker: systemctl start docker
Save the all the images:
docker save $(docker images |sed -e '/^<none>/d' -e '/^REPOSITORY/d' -e 's,[ ][ ]*,:,' -e 's,[ ].*,,') > /root/docker.img
Uninstall docker.
Erase everything in /var/lib/docker:
rm -rf /var/lib/docker/[cdintv]*
Reinstall docker
Enable docker: systemctl enable docker
Start docker: systemctl start docker
Restore images:
docker load < /root/docker.img
Start any persistent containers you need running.
This dropped my disk usage from 67 GB for docker to 6 GB for docker.
I do not recommend this for everyday use. But it is useful to run when it looks like docker has lost track of used disk space do to software errors, or unexpected reboots.

Answer 22

docker rm `docker ps -aq`
or
docker rm $(docker ps -q -f status=exited)

Answer 23

If you wish to automatically/periodically clean up exited containers and remove images and volumes that aren't in use by a running container you can download the image meltwater/docker-cleanup.
Just run:
docker run -d -v /var/run/docker.sock:/var/run/docker.sock:rw -v /var/lib/docker:/var/lib/docker:rw --restart=unless-stopped meltwater/docker-cleanup:latest
It runs every 30 minutes by default. You can however set the delay time by using this flag in seconds (DELAY_TIME=1800 option).
More details: https://github.com/meltwater/docker-cleanup/blob/master/README.md

Answer 24

If you build these pruned images yourself (from some other, older base images) please be careful with the accepted solutions above based on docker image prune, as the command is blunt and will try to remove also all dependencies required by your latest images (the command should be probably renamed to docker image*s* prune).
The solution I came up for my docker image build pipelines (where there are daily builds and tags=dates are in the YYYYMMDD format) is this:
# carefully narrow down the image to be deleted (to avoid removing useful static stuff like base images)
my_deleted_image=mirekphd/ml-cpu-py37-vsc-cust
# define the monitored image (tested for obsolescence), which will be usually the same as deleted one, unless deleting some very infrequently built image which requires a separate "clock"
monitored_image=mirekphd/ml-cache
# calculate the oldest acceptable tag (date)
date_week_ago=$(date -d "last week" '+%Y%m%d')
# get the IDs of obsolete tags of our deleted image
# note we use monitored_image to test for obsolescence
my_deleted_image_obsolete_tag_ids=$(docker images --filter="before=$monitored_image:$date_week_ago" | grep $my_deleted_image | awk '{print $3}')
# remove the obsolete tags of the deleted image
# (note it typically has to be forced using -f switch)
docker rmi -f $my_deleted_image_obsolete_tag_ids

Answer 25

See the official reference for docker system prune
docker system prune will remove:
all stopped containers
all networks not used by at least one container
all dangling images
all build cache
docker system prune -a will do the same, but in additional to removing all dangling images, it will more broadly remove:
all images without at least one container associated to them
What are dangling images?
Docker images consist of multiple layers that get wrapped inside a parent 'container layer' when the overall container image is generated from a Dockerfile. Dangling images are layers that have no relationship to any other tagged images, and will therefore never have any use within any new containers that are built. They no longer serve a purpose and consume disk space.
For example a dangling image can be created by the following process:
Build a named image my-image from Dockerfile, without specifying any tag:
FROM ubuntu:latest
CMD ["echo", "Hello World"]
docker build -t my-image
docker images
REPOSITORY TAG IMAGE ID
my-image latest 7ed6e7202eca <--- created, not dangling
ubuntu latest 825d55fb6340
Update the Dockerfile:
FROM ubuntu:latest
CMD ["echo", "Hello, World!"]
Rebuild image re-using the previous name, without specifying any tag:
docker build -t my-image
docker images
REPOSITORY TAG IMAGE ID
my-image latest da6e74196f66 <--- replacement layer
<none> <none> 7ed6e7202eca <--- previous layer, now dangling
ubuntu latest 825d55fb6340
The build created a new my-image layer. As we can see, the layer that was originally created is still there, but its name and tag are set to <none>:<none>. It will never be possible for this layer to be associated with any docker container layer, which means it's 'dangling'
What are images without at least one container associated to them?
An unused image means that it has not been assigned or used in a container. For example, docker ps -a will list all of your running and stopped containers. Any image being used by any of these containers is a "used image".
When running docker system prune -a, it will remove both unused and dangling images. Any image with at least one container associated to it will not be affected.

Answer 26

There is sparrow plugin docker-remove-dangling-images you can use to clean up stopped containers and unused (dangling) images:
$ sparrow plg run docker-remove-dangling-images
It works both for Linux and Windows OS.

Answer 27

If you have a lot of them, it can be really tedious to remove them, but lucky for us Docker has a few commands to help us eliminate dangling images. In older versions of Docker (and this still works today), you can delete dangling images on their own by running docker rmi -f $(docker images -f "dangling=true" -q) .

Answer 28

I usually do docker rm -f $(docker ps -a -q) and docker system prune to purge all dangling containers.

Answer 29

The below command will help to remove all unused and old images from local repository
==> docker system prune --all