Container Orchestration Basics

Project Overview

This project explores the fundamentals of container orchestration using Docker Compose and Docker Swarm. The goal was to deploy and manage a microservices-based application efficiently by leveraging these tools. The project involved setting up multiple Docker containers, configuring a Swarm cluster, and implementing load balancing.

Contents

1. Docker Compose Deployment
2. Virtual Machine Setup
3. Docker Swarm Cluster

Docker Compose Deployment

To orchestrate multiple microservices on a single machine, Docker Compose was utilized. The following steps were completed:

• Dockerfile Creation: Each microservice was containerized using individual Dockerfiles, ensuring proper dependencies and optimized image sizes.
• Docker Compose Configuration: A docker-compose.yml file was written to define service interactions, network configurations, and exposed ports.
• Application Deployment: The application was successfully deployed using docker-compose up, allowing inter-service communication.
• Testing with Postman: Predefined Postman test cases were executed to verify the correct functionality of the services.

Virtual Machine Setup

To simulate a multi-node environment, Vagrant was used to create virtual machines:

• Vagrantfile Configuration: A Vagrantfile was written to automate the setup of a virtual machine.
• Code Deployment: The application source code was transferred to the virtual machine’s working directory.
• Verification: The virtual machine was accessed via SSH to confirm that the application was correctly placed.

Docker Swarm Cluster

To achieve container orchestration across multiple nodes, a Docker Swarm cluster was configured:

• Multi-Node Setup: A modified Vagrantfile created three virtual machines (manager01, worker01, worker02).
• Automated Setup Scripts: Shell scripts were written to install Docker, initialize the Swarm cluster, and connect worker nodes.
• Docker Hub Integration: Application images were pushed to Docker Hub, enabling Swarm nodes to pull prebuilt images.
• Service Deployment: The docker stack deploy command was used to launch the microservices stack.
• NGINX Reverse Proxy: Configured to route traffic through an overlay network, making gateway service and session service accessible only via proxy.
• Testing & Verification: Postman tests were executed in the Swarm environment, confirming that the services functioned correctly.
• Container Distribution Analysis: Docker commands were used to inspect service distribution across Swarm nodes.
• Portainer Integration: Installed Portainer within the cluster to provide a graphical interface for monitoring and managing deployed services.

Conclusion

This project demonstrated the key principles of container orchestration, from running multiple containers with Docker Compose to deploying a fully functional Docker Swarm cluster. The implementation successfully showcased containerized microservices, automated scaling, and efficient service management, providing a strong foundation for real-world container orchestration scenarios.