The major problem of this approach is that on every build triggered, Docker will have to build the new image from scratch and it will not be able to leverage on the Docker layer caching. As you know, when building a new image each instruction within the Dockerfile is examined, and Docker looks for an existing image in its cache that it can reuse, rather than creating a new (duplicate) image. This implies that the building of new images will probably be much slower. So ideally we would like to keep on disk at least the latest version of our image, so that Docker can reuse previous created layers for building the new image quickly.
As an example, suppose we have a job/pipeline in Jenkins for building our images called "myDockerImage", using the Jenkins build number as image tags.
$ docker images REPOSITORY TAG IMAGE ID CREATED SIZE myDockerImage 456 1fdcfbbb6e95 2 days ago 1.2GB myDockerImage 455 e7deb97e4677 2 weeks ago 1.2GB myDockerImage 454 c4297a8dc099 2 weeks ago 1.2GB myDockerImage 453 36f69b5805d9 2 weeks ago 1.2GB ... ... ... ... ... centos 6.8 d63aca2e7714 6 weeks ago 195MB nginx 1.15.2-alpine 36f3464a2197 8 weeks ago 18.6MB postgres alpine e6c5e6a76255 8 months ago 38.2MB rabbitmq 3.6.14-alpine 5a9e735a5ad8 8 months ago 38.9MB openjdk 8u151-jre-alpine3.7 b1bd879ca9b3 8 months ago 82MB mysql 5.7 c356247174ed 2 months ago 372MB varnish latest ec0406c252f9 3 months ago 161MB alpine 3.7 3fd9065eaf02 8 months ago 4.15MB ruby 2.3.1 ffe8239a147c 22 months ago 730MB
As you can see, we have other images stored as well. Now, how could we delete all images of "myDockerImage" except the one we have just created? Let's take a look to the different options to the "
docker images" command:
$ docker images --help Usage: docker images [OPTIONS] [REPOSITORY[:TAG]] List images Options: -a, --all Show all images (default hides intermediate images) --digests Show digests -f, --filter filter Filter output based on conditions provided --format string Pretty-print images using a Go template --no-trunc Don't truncate output -q, --quiet Only show numeric IDs
The first step would be to list only the desired image (myDockerImage):
$ docker images myDockerImage REPOSITORY TAG IMAGE ID CREATED SIZE myDockerImage 456 1fdcfbbb6e95 2 days ago 1.2GB myDockerImage 455 e7deb97e4677 2 weeks ago 1.2GB myDockerImage 454 c4297a8dc099 2 weeks ago 1.2GB myDockerImage 453 36f69b5805d9 2 weeks ago 1.2GB ... ... ... ... ...
Then we could use the filter option (
-f) for listing only the images that were built "before" the one we have just built:
$ docker images --filter "before=myDockerImage:456" myDockerImage REPOSITORY TAG IMAGE ID CREATED SIZE myDockerImage 455 e7deb97e4677 2 weeks ago 1.2GB myDockerImage 454 c4297a8dc099 2 weeks ago 1.2GB myDockerImage 453 36f69b5805d9 2 weeks ago 1.2GB ... ... ... ... ...
Then we will use the option
-qfor listing only the numeric IDs, and the command "
docker rmi" for deleting the images in the list.
$ docker rmi $(docker images -q --filter "before=myDockerImage:456" myDockerImage)
Facing error according to your post
E:\JENKINS-SLAVES\SLAVE-1\workspace\My-Project-Swam>docker rmi $(docker images -q --filter "before=dsunaria/myprojectcicdswarm:54" dsunaria/myprojectcicdswarm)
unknown shorthand flag: 'q' in -q
See 'docker rmi --help'.
Is there any way I can run get the same output from cmd prompt as it's working on PowerShell but not on cmd.
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