Dynamic Load Balancer with Terraform, Ansible, and Docker

Table of Contents

1. Overview
2. Features
3. Repository Structure
4. Demo
5. Prerequisites
6. Setup Instructions
   • Step 1: Clone the Repository
   • Step 2: Run Development Environment in Docker
   • Step 3: Initialize and Apply Terraform
   • Step 4: Configure the Infrastructure with Ansible
7. Configuration

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Overview

This project provides a fully automated setup for deploying a dynamic load balancer and backend services on OpenNebula, leveraging modern tools like:

• Terraform: For resource provisioning.
• Ansible: For software configuration and deployment.
• Docker: For containerization of services.

The solution includes:

• An Apache-based load balancer.
• Configurable backend server nodes.
• Full automation for scaling and configuration.

Features

• Dynamic Scaling: Modify the number of backend nodes via a single Terraform variable.
• Infrastructure as Code (IaC): Reproducible, maintainable, and version-controlled infrastructure setup.
• Automated Configuration Management: Ansible ensures consistent environment setup across all nodes.
• Lightweight Containerization: Docker is used for deploying scalable services.

Repository Structure

.devcontainer/
  Dockerfile                # Dockerfile for building the dev environment
  devcontainer.json         # Dev container configuration
  docker-compose.yml        # Docker Compose file for the containerized dev environment
  init-iac-dev.sh           # Script to initialize SSH keys in the dev container
.github/workflows/
  main.yml                  # GitHub Actions workflow for CI/CD
ansible/
  roles/
    backend/
      tasks/
        main_tasks.yml      # Backend-specific Ansible tasks
      templates/
        index.html.j2       # Jinja2 template for backend web content
    load_balancer/
      tasks/
        main_tasks.yml      # Load balancer-specific Ansible tasks
      templates/
        apache              # Apache configuration templates
  inventory                 # Ansible inventory file for host management
  playbook.yml              # Main playbook orchestrating tasks
terraform/
  terraform.tf              # Terraform configuration for OpenNebula
  terraform.tfvars          # User-defined variables for Terraform
  variables.tf              # Terraform variables file
apache.conf.tmpl            # Template for Apache load balancer config
README.md                   # This documentation file

Demo

To see the project in action, visit the deployed application in your browser here: Load Balancer or put this command in your terminal:

curl http://147.228.173.116

Prerequisites

Before getting started, ensure the following tools are installed on your system:

• Docker: For running the development environment.
• Terraform: For provisioning cloud resources.
• Ansible: For configuring nodes.

Setup Instructions

Step 1: Clone the Repository

git clone https://github.com/VandlJ/iac-loadbalancer-automation.git
cd iac-loadbalancer-automation

Step 2: Run directory inside of Docker container

Step 3: Initialize and Apply Terraform

terraform init
terraform plan
terraform apply -auto-approve

This initializes, plans and applies confirguration for Terraform.

Step 4: Configure the Infrastructure with Ansible

ansible-playbook -i ansible/inventory ansible/playbook.yml

Configuration

To scale the number of backend servers, edit the variables.tf file in the Terraform configuration directory. For example:

variable "backend_count" {
  default = 3
}

After modifying the variable, reapply the Terraform configuration:

terraform apply -auto-approve