Day 16 Task: Docker for DevOps Engineers

what is Docker?

Docker is a software platform that allows you to build, test, and deploy applications quickly. Docker packages software into standardized units called containers that have everything the software needs to run, including libraries, system tools, code, and runtime. Using Docker, you can quickly deploy and scale applications into any environment and know your code will run.

1. Run a Docker Container

docker run hello-world

• This command downloads and runs the hello-world container to verify your Docker setup.

2. Inspect a Container or Image

docker inspect <container_id_or_image_name>

• Example:

docker inspect hello-world

• It provides detailed JSON output, including metadata, network settings, and mounts.

3. List Port Mappings of a Container

docker port <container_id_or_name>

• If you have an Nginx container running:

docker run -d -p 8080:80 --name mynginx nginx
docker port mynginx

• This will show the mapped ports (e.g., 80/tcp -> 0.0.0.0:8080).

4. View Resource Usage Statistics

docker stats

• This shows CPU, memory, network, and disk usage of all running containers.

5. View Running Processes in a Container

docker top <container_id_or_name>

• Example:

docker top mynginx

• Displays processes inside the container.

6. Save an Image to a TAR Archive

docker save -o myimage.tar <image_name>

• Example:

docker save -o nginx_backup.tar nginx

• This saves the nginx image to a file.

7. Load an Image from a TAR Archive

docker load -i myimage.tar

• Example:

docker load -i nginx_backup.tar

• This restores the previously saved image.

These commands will help you manage Docker containers efficiently. Let me know if you need further explanations! 🚀