How to remove old and unused Docker images

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 additio

Answer 1

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 2

How to remove a tagged image

1. docker rmi the tag first

2. 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 3

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 4

@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 5

This worked for me:

docker rmi $(docker images | grep "^<none>" | awk "{print $3}")

Answer 6

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