Docker Essential Commands Cheat Sheet

1. Docker Installation Check

docker --version
docker info

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2. Run a Docker Container

docker run hello-world

docker run -it ubuntu

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3. List Commands

docker ps              # List running containers
docker ps -a           # List all containers (including stopped)
docker images          # List downloaded images
docker volume ls       # List volumes
docker network ls      # List networks

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4. Image Management

docker pull <image_name>          # Download image
docker build -t myapp .           # Build image from Dockerfile
docker tag myapp myname/myapp:v1  # Tag image
docker rmi <image_id>             # Remove image

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5. Container Lifecycle

docker start <container_id>       # Start existing container
docker stop <container_id>        # Stop running container
docker restart <container_id>     # Restart container
docker rm <container_id>          # Remove container

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6. Build & Run from Dockerfile

docker build -t myapp .
docker run -d -p 8000:8000 myapp

-d: detached (background)
-p: map ports (host:container)

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7. Volume Mounting (for persistent data)

docker run -v $(pwd):/app myapp

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8. Copy Files In/Out

docker cp myfile.txt <container_id>:/app/
docker cp <container_id>:/app/output.txt .

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9. Execute Commands Inside Container

docker exec -it <container_id> bash

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10. Cleanup

docker stop $(docker ps -q)           # Stop all containers
docker rm $(docker ps -a -q)          # Remove all containers
docker rmi $(docker images -q)        # Remove all images
docker volume prune                   # Remove unused volumes
docker system prune                   # Clean up everything

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11. Docker Compose

docker-compose up -d      # Start all services
docker-compose down       # Stop and remove containers, networks
docker-compose build      # Build images

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Dockerfile Example

FROM python:3.11
WORKDIR /app
COPY . .
RUN pip install -r requirements.txt
CMD ["python", "app.py"]

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Happy Docking! 🐳