Docker has revolutionized the way developers build, ship, and run applications. Whether you're just starting out or looking to brush up on your skills, understanding key Docker commands can greatly enhance your workflow. In this blog post, we'll cover some of the most useful Docker commands and explain how to use them effectively.

Docker Basics

1. docker --version

Purpose: Check your Docker version.

docker --version

This command helps verify that Docker is installed and provides information about the installed version.

2. docker info

Purpose: Display system-wide information about Docker.

docker info

Use this command to get detailed information about your Docker installation, including the number of containers, images, and system resources.

Working with Containers

3. docker run

Purpose: Create and start a new container.

docker run -d -p 80:80 --name my_container nginx

This command starts a new container in detached mode (-d), maps port 80 of the host to port 80 of the container (-p 80:80), and names the container my_container.

4. docker ps

Purpose: List running containers.

docker ps

This command displays a list of all currently running containers, showing details like container ID, image, and ports.

5. docker stop

Purpose: Stop a running container.

docker stop my_container

This command stops the container named my_container. Use the container ID if the name is not specified.

6. docker rm

Purpose: Remove a stopped container.

docker rm my_container

After stopping a container, you can remove it using this command. This helps free up system resources.

7. docker exec

Purpose: Run a command inside a running container.

docker exec -it my_container /bin/bash

This command opens an interactive terminal session inside the container my_container. It’s useful for debugging and inspecting running containers.

Managing Images

8. docker images

Purpose: List all Docker images on the host.

docker images

This command displays a list of all images stored on your local Docker host, including repository names, tags, and sizes.

9. docker pull

Purpose: Download an image from a Docker registry.

docker pull node

This command fetches the latest node image from the Docker Hub, the default registry.

10. docker build

Purpose: Build an image from a Dockerfile.

docker build -t my_image:latest

This command builds a new Docker image from a Dockerfile in the current directory and tags it as my_image:latest.

11. docker rmi

Purpose: Remove an image.

docker rmi my_image:latest

This command deletes the specified image from your local Docker host.

Networks and Volumes

12. docker network ls

Purpose: List all Docker networks.

docker network ls

This command shows all networks available on your Docker host, including bridge, host, and overlay networks.

13. docker network create

Purpose: Create a new Docker network.

docker network create my_network

This command creates a new network named my_network.

14. docker volume ls

Purpose: List all Docker volumes.

docker volume ls

This command displays all volumes created on your Docker host, which are used for persistent data storage.

15. docker volume create

Purpose: Create a new Docker volume.

docker volume create my_volume

This command creates a new volume named my_volume.

Cleaning Up

16. docker system prune

Purpose: Clean up unused Docker objects.

docker system prune

This command removes all stopped containers, unused networks, dangling images, and build caches to free up space.

Conclusion

Mastering these Docker commands will help streamline your development workflow and make managing containers more efficient. Whether you're building applications, testing new environments, or deploying services, these commands provide a solid foundation for working with Docker.

Happy Dockering!