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Docker images deep dive

• docker pull <image_name> pulls the image from registry (default is docker hub

  docker.io)

• Pulling an Image is a 2 step process (from docker.io or any other registry i.e. google container registry aka gcr.io etc).
• It pulls a fat manifest and then checks for OS type and architecture to pull actual image manifest.
• images are then pulled in seperate layers.

• Images are hashed for integrity

Behind the sceene

• The storage driver keeps and manages the images cached locally

• Lets browse the Docker Root Dir: /var/lib/docker to inspect the local images

• docker history <image_name> will show you how the image is built by layers

• docker inspect <image_name> will provide the config and manifest of that image

and Layers too if you scroll it down

• Finally docker image rm <image_name> OR docker rmi <image_id> will remove the locally cached image