Docker image operations¶

Docker image operations encompass the lifecycle management of Docker images, including listing, tagging, removing, and transferring images between local machines and registries^[600-developer__docker__docker.md].

Listing Images¶

To view all images currently stored on the local machine, use the docker image ls command^[600-developer__docker__docker.md]. This command lists the repositories, tags, and image IDs available^[600-developer__docker__docker.md]. A common alias for this operation is docker images^[600-developer__docker__docker.md].

Command: docker image ls or docker images
Output: Displays REPOSITORY, TAG, IMAGE ID, CREATED, and SIZE^[600-developer__docker__docker.md].

Tagging Images¶

Before an image can be uploaded to a registry, it must be tagged with a username and repository name^[600-developer__docker__docker.md]. The docker tag command creates a new reference to an existing image ID^[600-developer__docker__docker.md].

Syntax: docker tag <image> username/repository:tag^[600-developer__docker__docker.md]
Example: Tagging docker.io/hello-world to yudady/hello prepares it for a specific user repository^[600-developer__docker__docker.md].

Removing Images¶

To remove an image from the local machine, use the docker image rm command followed by the Image ID or repository name^[600-developer__docker__docker.md]. An alias for this command is docker rmi^[600-developer__docker__docker.md].

Prerequisites for Removal¶

Docker will prevent the removal of an image if it is currently being used by a container, even if that container is stopped^[600-developer__docker__docker.md].

Step 1: Check for running or stopped containers using docker ps -a^[600-developer__docker__docker.md].
Step 2: Remove any conflicting containers using docker rm <container_id>^[600-developer__docker__docker.md].
Step 3: Remove the image using docker rmi <image_id>^[600-developer__docker__docker.md].

To remove all local images, one can use the command docker image rm $(docker image ls -a -q)^[600-developer__docker__docker.md].

Pushing Images¶

The docker push command uploads a tagged image from the local environment to a Docker registry^[600-developer__docker__docker.md].

Command: docker push username/repository:tag^[600-developer__docker__docker.md]
Context: This operation requires the user to be logged in to the registry via docker login^[600-developer__docker__docker.md].

Sources¶

^[600-developer__docker__docker.md]