Docker images are templates for creating Docker containers. They contain all the necessary components, such as code, libraries, and dependencies, to run an application. Managing Docker images is an important part of using Docker, as it allows you to create new containers, push images to a registry, and remove unused images.
In this article, we will go over how to manage Docker images, including how to list, pull, create, and remove images.
Searching Docker Images
You can run `docker search image_name` to search for available images on docker hub. For example to search images for “nginx” execute the following command.
docker search nginx
You can also search for images directory at: https://hub.docker.com/
Listing Docker Images
To list the Docker images on your system, you can use the docker images command. This command will display a list of all available images, including the image ID, repository, tag, and size.
For example, to list all Docker images, you can use the following command:
docker images
You can also use the -a flag to list all images, including intermediate images that are used to build other images.
docker images -a
Pulling Docker Images
To pull a Docker image from a registry, you can use the docker pull command followed by the image name. The image name should include the repository and tag, separated by a colon.
For example, to pull the latest version of the nginx image from the official repository, you can use the following command:
docker pull nginx
You can also specify a specific tag to pull a specific version of the image. For example, to pull the 1.17.9 version of the nginx image, you can use the following command:
docker pull nginx:1.17.9
Creating Docker Images
To create a Docker image, you can use the docker build command followed by the path to the directory containing the Dockerfile. The Dockerfile is a text file that contains the instructions for building the image.
For example, to build an image from the Dockerfile in the current directory, you can use the following command:
docker build .
You can also specify a tag for the image using the -t flag. For example, to build an image with the tag myimage:latest, you can use the following command:
docker build -t myimage:latest .
Removing Docker Images
To remove a Docker image, you can use the docker rmi command followed by the image ID or image name. You can get a list of all available images on your system by running the docker images command.
For example, to remove an image with the ID abc123, you can use the following command:
docker rmi abc123
To remove an image with the name myimage, you can use the following command:
docker rmi myimage
You can also remove multiple images at once by specifying a list of image IDs or names separated by spaces.
docker rmi abc123 def456 ghi789
Conclusion
Managing Docker images is an important part of using Docker. By understanding how to list, pull, create, and remove images, you can keep your system organized and efficient. By using the appropriate commands, you can easily