delete docker image failed

Posted on | Edited on | In

problem

docker images -a

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[root@CN-BJI-D-de9f66 ~]# docker images -a
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
<none>              <none>              72dc10d3deba        22 hours ago        230MB
tdtest              latest              e3ad759bb993        22 hours ago        230MB
<none>              <none>              820bc1802af7        22 hours ago        230MB
...
<none>              <none>              ac8cea40eaa0        22 hours ago        223MB
centos              latest              0f3e07c0138f        2 weeks ago         220MB
redis               latest              01a52b3b5cd1        2 weeks ago         98.2MB
ubuntu              latest              2ca708c1c9cc        3 weeks ago         64.2MB
redis               alpine              ed7d2ff5a623        8 weeks ago         29.3MB

when put command docker rmi 820bc1802af7, <none>:<none> image delete fail.

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Error response from daemon: conflict: unable to delete 820bc1802af7 (cannot be forced) - image has dependent child images

this is cause by has other images depend on this image 820bc1802af7.
use docker image inspect, find current image’s child image, repository tag name.

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[root@CN-BJI-D-de9f66 ~]# docker image inspect --format='{{.RepoTags}} {{.Id}} {{.Parent}}' $(docker image ls -q --filter since=820bc1802af7)
[tdtest:latest] sha256:e3ad759bb99351a4951df11113e0ad3914a26d55e99e5243e13ebac19373efae sha256:8abd1595d4dfc922b81825940c0f6d73034eeb10b3e2b12a78b3d0e33d78588e

mechanism

kind one

<none>:<none> images which be related to the image be deleted will be deleted as will.
this kind of <none>:<none> is middle image, it won’t occupy space.

kind two

make a docker image docker build -t hello-world ./

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FROM centos:latest
RUN echo 'hello world'

when centos have a new release, build hello-world image again, it will depend on the latest centos.
the hello-world depend on older centos, will become <none>:<none> dangling image.
this kind of <none>:<none> occupy space, it was originally tag image.

all docker file store at /var/lib/docker/graph in default, docker be called graph layer database.
use command docker rmi $(docker images -f "dangling=true" -q) to delete wandering image layer.

other command

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# stop all container
docker ps -a | grep "Exited" | awk '{print $1 }'|xargs docker stop

# delete all container
docker ps -a | grep "Exited" | awk '{print $1 }'|xargs docker rm

# delete all none container
docker images|grep none|awk '{print $3 }'|xargs docker rmi

http://www.ibloger.net/article/3217.html
https://segmentfault.com/a/1190000011153919
https://blog.csdn.net/sin_geek/article/details/86736417