Highly Available and Scalable Web Application CloudFormation Templates

Overview

This document provides a guide for deploying a 3-phase AWS infrastructure using CloudFormation templates. The setup includes EC2 instances, networking components, a MySQL RDS database, and an Auto Scaling environment. A migration script is included to transfer data from an EC2-hosted MySQL instance to the RDS instance.

Files

• Phase1.yml
  Sets up a public subnet and an EC2 instance running MySQL.
• Phase2.yml
  Creates an RDS instance and securely stores credentials in AWS Secrets Manager.
• Phase3.yml
  Configures an Application Load Balancer, Auto Scaling Group, and security groups to ensure high availability.
• DB_migrator.sh
  Automates data migration from the Phase1 EC2 instance to the RDS instance.

Usage

1. Create S3 Bucket

Upload Phase1.yml, Phase2.yml, and Phase3.yml to an S3 bucket for easy access during stack creation.

2. Create Key Pairs

Generate two EC2 Key Pairs: one for instances in public subnets and another for instances in private subnets.

3. Store Key Pairs in Secrets Manager

• Save the Key Pair files and store their contents in AWS Secrets Manager.
• The DB_migrator.sh script expects the following secret structure:

  {
      "RSA_KEYS": {
          "Key": "Value",
          "PUBLIC": "-----BEGIN RSA-----\nMIIEowIBAA... ...KCAQEAqz9z\n-----END RSA-----",
          "PRIVATE": "-----BEGIN RSA-----\nMIIEowIBAA... ...KCAQEAqz9z\n-----END RSA-----"
      }
  }
  

4. Launch Phase1 CloudFormation Stack

• Deploy the Phase1.yml CloudFormation stack. This stack will create nested stacks for Phase2.yml and Phase3.yml.
• Ensure an IAM role with the necessary permissions is attached to the stack.

5. Verify Stack Outputs

• Wait for all stack deployments to complete.
• Review the output values of each stack for key information, such as web application URLs and RDS instance details.

6. Create a Migration Environment

• Set up a Cloud9 environment or launch an ephemeral EC2 instance to run the migration script.

7. Link Security Groups

• Update security group configurations to allow the Cloud9 or EC2 instance to communicate with the Phase1 EC2 instance (hosting the local MySQL database) and the RDS instance.

8. Run Migration Script

• Execute the DB_migrator.sh script on the Cloud9 or EC2 instance. The script will automatically transfer data from the local MySQL database to the RDS instance.

Conclusion

By following this guide, you can deploy a scalable and highly available AWS infrastructure with ease. The included migration script simplifies the process of moving data to the cloud, ensuring a seamless transition. For any issues or further customization, refer to AWS documentation or consult your AWS administrator.