CODEWITHSUNDEEP
docker
M.I
M.I

Reputation: 303

docker build creates another set of docker image even the build command is the same?

Assume that you can create a 500MB docker image with following command

docker build -t demo:1.0 .

It seems to me that the docker image (demo:1.0) is overwritten when I re-run the same command. However, I noticed that free disk space decreases as I re-run the command. Why does this happen? Is docker creating another set of the image somewhere in the file system? I'd like to know how I can find old-generations of the docker images and delete them.

Upvotes: 1

Views: 61

Answers (1)

vitr
vitr

Reputation: 7134

It's standard docker behavior, if you run

docker images

you may see a dangling image like this

REPOSITORY          TAG                 IMAGE ID            CREATED           VIRTUAL SIZE
demo                1.0                 a1b38444260e        6 days ago          500 MB
<none>              <none>              46250b7172c5        6 days ago          500 MB

You can remove the dangling images with the command

docker rmi $(docker images -qa -f "dangling=true")

Docker doesn’t delete such images automatically, despite, it's a logical feature to have. For now this command can be used to do a manual deletion.

While the images are stored in /var/lib/docker/{driver-name}, you wouldn't remove images manually from that path.

Upvotes: 1

Related Questions