Docker Compose

• Docker Compose is a tool provided by Docker that allows you to define and manage multi-container Docker applications. It simplifies the process of running and orchestrating multiple Docker containers as a cohesive application.

• With Docker Compose, you can define the services, networks, volumes, and other configurations for your application in a single YAML file called a "docker-compose.yml" file. This file serves as a blueprint for your application's architecture and allows you to specify the relationships and dependencies between the containers.

YAML in Docker

• YAML (YAML Ain't Markup Language) refers to a popular data serialization format that is human-readable and commonly used for configuration files, data exchange, and storing structured data.

• In Docker, YAML (YAML Ain't Markup Language) is a human-readable data serialization format used for configuring and defining Docker Compose files. Docker Compose is a tool that allows you to define and manage multi-container Docker applications.

Task 1: Running Multiple Containers using Docker Compose

1. Get the repository

    mkdir proj2
    cd proj2
    git clone https://github.com/Abhisek773/node-todo-cicd.git
    cd node-todo-cicd
   

2. Install docker-compose

    sudo apt-get install docker-compose -y
   

   

3. Create docker-compose.yaml file and configure all the details

   

    vim docker-compose.yaml
   
    #file contains
    version: '3.9'
   
    services:
      web:
        image: abhisek6/node_todo_app:latest
        ports:
          - "8000:8000"
   

4. To start the container we use docker-compose up

   

    docker-compose up -d
   

5. Now the application is up & running.

   

6. To bring down the application we use docker-compose.

    docker-compose down
   

   

Task 2: Docker Commands

1. Pull a pre-existing Docker image from a public repository (e.g. Docker Hub) and run it on your local machine. Run the container as a non-root user (Hint- Use usermod command to give the user permission to docker). Make sure you reboot the instance after permitting the user.

    docker pull abhisek6/react_django_app:latest
   

   

2. Inspect the container's running processes and exposed ports using the docker inspect command.

    docker inspect <container_id>
   

   

3. Use the docker logs command to view the container's log output.

    docker log <container_id>
   

   

4. Use the docker stop and docker start commands to stop and start the container.

    docker stop <container_id>
    docker start <container_id>
   

   

5. Use the docker rm command to remove the container when you're done.

    # Before removing container it should be stopped first
    docker rm <container_id>
   

   

Thank You,

I want to express my deepest gratitude to each and every one of you who has taken the time to read, engage, and support my journey as a becoming DevOps Engineer.

Feel free to reach out to me if any corrections or add-ons are required on blogs. Your feedback is always welcome & appreciated.

~ Abhisek Moharana 😊