Generic Commands

• List objects: docker <object> ls
• Inspect object: docker <object> inspect <name/id>
• Remove object: docker <object> rm <name/id>
• Remove unused objects: docker <object> prune

Docker Images

• Image Registry: Collection of Docker images
  • Types:
    • Custom/Private: Hosted by organizations/companies
    • Public: Hosted at hub.docker.com
• Commands:
  • List images: docker image ls
  • Pull image: docker image pull <image-name> (e.g., docker image pull hello-world)
  • Inspect image: docker image inspect <image-name> (e.g., docker image inspect hello-world)
  • Remove image: docker image rm <image-name/id> (e.g., docker image rm hello-world)
  • Remove unused images: docker image prune

Custom Images

• Creation: Use a Dockerfile
  • Requires a base image
  • Key Commands:
    • FROM: Specify base image
    • COPY: Copy files from local to image (COPY <local-path> <image-path>)
    • EXPOSE: Expose port for container
    • RUN: Execute commands during build
    • CMD: Execute command when container starts
    • WORKDIR: Set/create working directory
    • ENV: Set environment variable
• Push to Docker Hub:
  • Sign up at hub.docker.com (free)
  • Rename image: <docker-hub-username>/<image-name>
  • Login: docker login
  • Commands:
    • Build image: docker image build -t <image-name> <context> (e.g., docker image build -t mywebsite .)
    • Tag image: docker image tag <old-name> <new-name> (e.g., docker image tag mywebsite amitksunbeam/mywebsite)
    • Push image: docker image push <image-name>

Docker Containers

• Characteristics:
  • Run one application at a time
  • Stop when application finishes/errors
  • Data not persisted; lost if container removed
• Commands:
  • List running containers: docker container ls
  • List all containers: docker container ls -a (Statuses: Created, Running, Exited)
  • Create container: docker container create <image-name/id> (e.g., docker container create hello-world)
  • Start container: docker container start <name/id>
  • Stop container: docker container stop <name/id>
  • View logs: docker container logs <name/id>
  • Inspect container: docker container inspect <name/id>
  • Remove exited container: docker container rm <name/id>
  • Remove running container: docker container rm -f <name/id>
  • Run in foreground: docker container run <image-name/id> (e.g., docker container run httpd)
  • Run with options: docker container run -d -i -t --name <name> -p <host-port>:<container-port> -v <volume>:<mount-path> <image-name/id>
    • d: Detached mode (background)
    • i: Interactive mode
    • t: Allocate terminal
    • -name: Set container name
    • p: Publish port
    • e: Set environment variable
    • v: Attach volume
    • Example: docker container run -d -i -t --name myhttpd -p 8080:80 httpd
    • MySQL example: docker container run -itd --name mysql -p 3306:3306 -e MYSQL_ROOT_PASSWORD=root -v mysql-volume:/var/lib/mysql mysql
  • Execute command: docker container exec <name/id> <command> (e.g., docker container exec myhttpd date)
  • Get terminal: docker container exec -it <name/id> bash (or sh)
  • Remove unused containers: docker container prune

Docker Volumes

• Commands:
  • List volumes: docker volume ls
  • Create volume: docker volume create <volume-name> Fordocker volume rm <volume-name>`
  • Remove unused volumes: docker volume prune