docker_commands.md

🐳 Docker Commands Cheat Sheet with Explanations

🔧 Docker Installation & Setup

Command	Description
docker --version	Check the installed Docker version.
docker info	Display detailed info about Docker environment (images, containers, drivers).
docker login	Authenticate to a Docker registry (e.g., Docker Hub).

📦 Working with Docker Images

Command	Description
docker images	List all locally available Docker images.
docker pull <image>	Download an image from Docker Hub or a registry.
docker build -t <name>:<tag> .	Build an image from a Dockerfile in the current directory.
docker tag <image> <repo>/<image>:<tag>	Add a custom name/tag to an image.
docker push <repo>/<image>:<tag>	Upload an image to Docker Hub or a private registry.
docker rmi <image>	Remove a Docker image from your system.

🚀 Working with Containers

Command	Description
docker ps	List running containers.
docker ps -a	List all containers (running + stopped).
docker run <image>	Run a container from an image.
docker run -it <image> /bin/bash	Start a container with interactive terminal.
docker run -d <image>	Run a container in detached mode (in background).
docker run --name <name> <image>	Assign a custom name to the container.
docker exec -it <container> /bin/bash	Access a running container shell.
docker start <container>	Start a stopped container.
docker stop <container>	Stop a running container.
docker restart <container>	Restart a container.
docker rm <container>	Remove a container.
docker rm -f <container>	Force remove a running container.

🗂️ Volumes & Data Management

Command	Description
docker volume create <volume>	Create a Docker volume for persistent data.
docker volume ls	List all volumes.
docker volume inspect <volume>	Show detailed info about a volume.
docker run -v <volume>:/path/in/container <image>	Mount a volume inside a container.
docker volume rm <volume>	Remove a volume.

🌐 Docker Networking

Command	Description
docker network ls	List all Docker networks.
docker network create <network>	Create a custom network.
docker network inspect <network>	Inspect details of a network.
docker network connect <network> <container>	Connect a container to a network.
docker run --network=<network> <image>	Start container attached to a specific network.

🛠️ Dockerfile & Image Customization

Dockerfile Command	Purpose
FROM	Base image to use (e.g., ubuntu, alpine).
RUN	Execute commands while building the image.
COPY / ADD	Copy files from host into image.
WORKDIR	Set working directory in container.
CMD	Default command to run when container starts.
ENTRYPOINT	Configure container startup behavior.
EXPOSE	Define ports the container listens on.
ENV	Set environment variables in the image.

🛠 Build Example:

docker build -t myapp:latest .

📂 Docker Compose Commands

Docker Compose allows you to define and run multi-container Docker applications using a single docker-compose.yml file.

Command	Description
docker-compose up	Start all services defined in the docker-compose.yml. Builds images if not present.
docker-compose up -d	Run all services in detached (background) mode.
docker-compose down	Stop and remove all running containers, networks, and volumes created by Compose.
docker-compose build	Build or rebuild services defined in docker-compose.yml.
docker-compose ps	List all containers managed by the current Compose setup.

📊 Docker Logs & Monitoring

Monitor your running containers and services in real-time.

Command	Description
docker logs <container>	Display the logs of a specific container. Useful for debugging.
docker stats	Show real-time CPU, memory, network, and I/O usage for all containers.
docker inspect <container or image>	Return low-level detailed JSON info about a container or image (e.g., IP, mount points, labels).
docker events	Stream real-time events from the Docker daemon (e.g., container start/stop).

🧼 Docker Cleanup Commands

Reclaim disk space by cleaning unused, dangling, or stopped Docker resources.

Command	Description
docker system prune	Remove all unused containers, networks, dangling images, and build cache. Interactive prompt by default.
docker image prune	Remove dangling (unreferenced) images.
docker container prune	Remove all stopped containers.
docker volume prune	Delete all unused volumes.
docker builder prune	Clean up the build cache used by Docker image builds.