In today’s fast-paced development environment, deploying applications quickly and reliably is crucial. Blue/Green deployments are a popular strategy to achieve zero-downtime updates. AWS Systems Manager Automation provides a powerful way to streamline and automate this process. This guide will walk you through using AWS Systems Manager Automation for Blue/Green deployments on EC2 instances, ensuring seamless and efficient rollouts.

Introduction: Why Systems Manager Automation for Blue/Green Deployments?

Blue/Green deployments reduce downtime and risk by running two identical production environments—Blue and Green. One environment (Blue) serves live traffic, while the other (Green) stands by for updates. Once updates are verified on the Green environment, traffic switches over seamlessly. AWS Systems Manager Automation simplifies this process by automating the complex steps involved in a Blue/Green deployment, ensuring consistency, reducing human error, and saving time.

Project Overview: Infrastructure and Tools

Infrastructure:

  • AWS EC2 Instances: The core compute resources for running applications.
  • Amazon Route 53: For managing DNS and routing traffic between Blue and Green environments.
  • AWS Systems Manager Automation: To orchestrate the deployment process.
  • Amazon S3: For storing deployment scripts and artifacts.

Tools:

  • AWS CLI: For command-line interactions with AWS services.
  • IAM Roles: To provide necessary permissions to AWS resources.

Systems Manager Automation Runbook: A Step-by-Step Breakdown

A Systems Manager Automation runbook is a predefined series of steps to automate tasks. For Blue/Green deployments, the runbook will:

  1. Initialize: Set up initial variables and permissions.
  2. Deploy to Green: Update the Green environment with new changes.
  3. Test Green: Verify the Green environment is working correctly.
  4. Switch Traffic: Update Route 53 to route traffic from Blue to Green.
  5. Clean Up: Archive logs and clean up temporary resources.

Blue/Green Deployment Script: Deep Dive into the Core Logic

Core Script Components:

  1. Initialization: Define variables for the Blue and Green environments, such as instance IDs and Route 53 settings.
  2. Deployment to Green: Use Systems Manager Automation documents to apply updates to the Green environment. This includes stopping the Green instances, deploying the new version, and starting the cases.
  3. Testing: Run automated tests to ensure the Green environment is functioning correctly.
  4. Traffic Switching: Update DNS records in Route 53 to direct traffic to the Green environment.
  5. Rollback Logic: Include steps to revert to the Blue environment in case of issues.

Visualizing the Deployment: Schemas for Clarity

Deployment Workflow Diagram:

  • Start: Initialize the process.
  • Deploy to Green: Apply updates.
  • Test Green: Validate the deployment.
  • Switch Traffic: Route traffic to Green.
  • Monitor: Ensure stability.
  • Clean Up: Archive logs and reset the environment.

Prerequisites and Deployment Steps: A Practical Guide

Prerequisites:

  1. AWS CLI Installed: Ensure AWS CLI is installed and configured.
  2. IAM Roles: Set up IAM roles with appropriate permissions.
  3. S3 Bucket: Create an S3 bucket to store scripts and logs.
  4. EC2 Instances: Launch Blue and Green environments.

Deployment Steps:

  1. Upload Scripts to S3: Store deployment scripts and artifacts in an S3 bucket.
  2. Create Automation Document: Define the steps for the deployment in an AWS Systems Manager Automation document.
  3. Run the Automation: Execute the Automation document to deploy updates to the Green environment.
  4. Test and Switch Traffic: Validate the Green environment and update Route 53 to route traffic.
  5. Monitor and Cleanup: Monitor the deployment and clean up resources.

Testing and Cleanup: Ensuring Success and Maintaining Order

Testing:

  • Automated Tests: Run automated scripts to validate the functionality of the Green environment.
  • Manual Checks: Perform manual checks to ensure everything works as expected.

Cleanup:

  • Log Archiving: Store logs in S3 for auditing and troubleshooting.
  • Resource Cleanup: Terminate unnecessary instances and clean up temporary resources.

Conclusion: The Power and Flexibility of Systems Manager Automation

AWS Systems Manager Automation offers a robust, flexible solution for managing Blue/Green deployments. You can achieve faster, more reliable updates with minimal downtime by automating the deployment process. This approach ensures your applications remain available and performant, even during updates.

References

Automating Blue/Green Deployments of Infrastructure and Application Code using AMIs, AWS Developer Tools, & Amazon EC2 Systems Manager

Accelerating Blue/Green Deployments with AWS MGN Post-Launch Actions