Docker CMDs

20 Feb 2024     #docker

Image

Search for an Image

docker search [OPTIONS] IMAGE_NAME

• --automated=false Show only automated builds
• --no-trunc=false Show all results
• -s=n --stars=n Show only images with at least n stars
• e.g.,

  docker search --stars=100 mysql
  

Download an Image

docker pull [OPTIONS] IMAGE_NAME[:TAG_NAME]

• -a Download all versions of the image
• TAG_NAME Specify the version to download, if not specified, the latest version is downloaded
• e.g.

  docker pull ubuntu:22.04
  

List Images

docker images [OPTIONS] [REPOSITORY]

• -a --all Show all images
• --digests Show digests
• -q --quiet Show only image IDs
• *To list containers: docker ps

Inspect Image Details

docker image inspect IMAGE_ID

• You can enter part of the ID instead of the full ID.

Delete an Image

docker rmi [OPTION] IMAGE_NAME:TAG_NAME

• -f Force delete the image of a running container, but in practice, it only untagged and does not actually delete the image or container.
• Delete multiple images at once:

  docker rmi IMAGE_NAME_1 IMAGE_NAME_2 ...
  

• Stop all running containers of a specific image and then delete the image:

  docker rm -f $(docker ps -a --filter ancestor=IMAGE_NAME)
  docker rmi IMAGE_NAME
  

Save and Load Images

docker save -o DIRECTORY IMAGE_NAME

• -o (output) Specify the directory to save the image

docker load -i DIRECTORY

• -i Specify the directory of the image to load (input), the image in that directory is loaded.

Tag an Image

docker tag IMAGE_NAME:TAG NEW_NAME:NEW_TAG

• Allows you to reference an existing image with a new name and tag.
• e.g.,

  docker tag ubuntu:22.04 abcd:0.1
  

Container

List Containers

docker ps [OPTION]

• Lists running containers.
• -a Show all containers, including those that have stopped.

Inspect Container Details

docker inspect CONTAINER_NAME

Run a Container from an Image

docker run [OPTIONS] IMAGE_NAME

• --name CONTAINER_NAME Set the container name
• --rm Delete the container after the run command is executed. One-time use of the container
• -it Keep passing terminal input to the container
  • -i Keep stdin open even if not attached
  • -t Allocate a pseudo-TTY, use TTY mode to write commands to the shell
• -d Run the container in the background. When this option is specified, the container ID is output.
• -e Add environment variables. Use as many as you need to add.
  • e.g.,

    docker run -e APP_ENV=production APP2_ENV=dev ubuntu:22.04 env
    

• -p HOST_PORT:CONTAINER_PORT Bind a specific port of the container connected to the host to the port of the host. Usually used to expose the web server port to the outside.
• -w DIR Change the working directory
• -v HOST_DIR:CONTAINER_DIR Mount a specific directory of the host to the container
  • e.g.,

    docker run -v volume:/data ubuntu:22.04
    

  • Mount the current working directory to the container

    docker run -v `pwd`:/opt ubuntu:22.04
    

• -u USER_ID Access the container with a specific user ID. The account must be added when building the image.

Execute Commands in a Running Container

docker exec CONTAINER_ID or NAME CMD

• -it Run the shell in the container environment,

Difference between run and exec

• run: Run a container from an image
• exec: Run commands in an already running container

Stop a Container

docker stop CONTAINER_ID/NAME

• Stop a running container (Graceful shutdown)

docker kill CONTAINER_ID/NAME

• Force stop a running container

Restart a Container

docker start CONTAINER_ID/NAME

• Restart a stopped container

docker restart CONTAINER_ID/NAME

• Stop and then restart the container