Docker cheatsheet

🚀 Docker Basics

Version & Help

docker --version                # Check Docker version
docker info                     # Show system-wide information
docker help                     # Show all commands
docker <command> --help         # Get help for a specific command

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📦 Container Management

Running Containers

docker run hello-world                        # Run a test container
docker run -it ubuntu bash                    # Run a container interactively
docker run -d -p 8080:80 nginx                # Run a container in detached mode
docker run --rm alpine echo "Hello, Docker!" # Auto-remove container after exit
docker run --name my-container nginx          # Run with a custom name
docker run --env MY_VAR=value alpine env      # Pass environment variables
docker run -v /host/path:/container/path ubuntu # Mount a volume

Stopping & Removing Containers

docker ps                         # List running containers
docker ps -a                      # List all containers
docker stop <container_id>         # Stop a running container
docker start <container_id>        # Start a stopped container
docker restart <container_id>      # Restart a container
docker rm <container_id>           # Remove a stopped container
docker rm -f <container_id>        # Force remove a running container
docker kill <container_id>         # Kill a container immediately

Inspecting Containers

docker logs <container_id>         # View container logs
docker logs -f <container_id>       # Follow logs (live output)
docker inspect <container_id>       # Get detailed container info
docker top <container_id>           # Show running processes
docker stats                        # Show resource usage of all containers
docker exec -it <container_id> bash # Enter a running container

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📜 Image Management

Working with Images

docker images                        # List all downloaded images
docker pull ubuntu                    # Download an image
docker push myrepo/myimage            # Push image to Docker Hub
docker tag myimage myrepo/myimage:v1  # Tag an image
docker rmi <image_id>                 # Remove an image
docker history <image_id>              # Show image history

Building Images

docker build -t myimage .              # Build an image from a Dockerfile
docker build -f MyDockerfile -t myapp . # Specify a different Dockerfile

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📂 Volumes & Storage

docker volume create myvolume           # Create a volume
docker volume ls                        # List volumes
docker volume inspect myvolume          # Inspect a volume
docker volume rm myvolume               # Remove a volume
docker run -v myvolume:/data ubuntu     # Attach a volume to a container
docker run --mount type=bind,source=/host/path,target=/container/path ubuntu # Bind mount

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📡 Networking

docker network ls                         # List networks
docker network create mynetwork           # Create a new network
docker network inspect mynetwork          # Inspect a network
docker network connect mynetwork mycontainer  # Connect a container to a network
docker network disconnect mynetwork mycontainer  # Disconnect a container
docker run --network=mynetwork nginx      # Run a container in a specific network

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🐳 Docker Compose

docker-compose up                         # Start services in the background
docker-compose up -d                      # Start services in detached mode
docker-compose down                        # Stop and remove containers, networks
docker-compose restart                     # Restart all services
docker-compose logs                        # View logs of all services

📌 Example docker-compose.yml

version: "3"
services:
  web:
    image: nginx
    ports:
      - "8080:80"
  db:
    image: mysql
    environment:
      MYSQL_ROOT_PASSWORD: example

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🔥 Other Useful Commands

docker system df # Show disk usage
docker system prune -a # Remove all unused images, containers, and networks
docker save -o myimage.tar myimage # Save image to a tar file
docker load -i myimage.tar # Load image from a tar file