DevOps & Cloud

Multi-Region AWS Infrastructure with Terraform

Designed and implemented a highly available multi-region AWS infrastructure using Terraform for a financial services application requiring 99.99% uptime SLA. Built automated failover mechanisms, cross-region data replication, and disaster recovery procedures reducing RTO from 4 hours to 15 minutes.

DevOps Cloud Engineer Platform Engineer

Terraform Terragrunt AWS VPC Route53 Global Accelerator ECS RDS DynamoDB S3 CloudFront AWS DMS Terratest GitHub Actions

Multi-Region AWS Infrastructure with Terraform

The Problem

Our fintech application ran exclusively in us-east-1, creating a single point of failure with no disaster recovery plan. During an AWS availability zone outage in 2023, we experienced 4 hours of complete downtime, resulting in $180K revenue loss and erosion of customer trust. We had no automated failover, no cross-region data replication, and manual recovery procedures that took hours to execute. Compliance requirements (SOC 2, PCI-DSS) mandated sub-1-hour RTO and 15-minute RPO, which we couldn't meet. The application state was tightly coupled to a single RDS instance with no read replicas.

The Solution

**Multi-Region Architecture**: Designed active-active infrastructure across us-east-1 (primary) and us-west-2 (secondary) using Route53 health checks for automatic DNS failover. Implemented AWS Global Accelerator for static anycast IPs and optimized routing.

**Infrastructure as Code**: Architected modular Terraform configurations with DRY principles, creating reusable modules for VPC, ECS clusters, RDS, S3, and CloudFront. Used Terragrunt for managing environment-specific configurations and remote state locking in DynamoDB. Implemented CI/CD pipeline for infrastructure changes with automated testing using Terratest.

**Data Replication Strategy**: Configured DynamoDB global tables for real-time cross-region replication of session and cache data. Set up S3 cross-region replication with versioning for static assets and backups. Implemented RDS read replicas in us-west-2 promoted to standalone instances with near-zero RPO using AWS Database Migration Service for ongoing replication.

**Disaster Recovery Testing**: Conducted monthly failover drills simulating region failure, achieving full recovery in under 12 minutes. Created automated runbooks and chaos engineering scenarios to validate resilience.

Key Highlights

Achieved 99.99% uptime SLA over 12 months (previously 99.5%)
Reduced global latency by 40% with multi-region active-active setup
Automated failover completing in under 60 seconds with zero data loss
Decreased infrastructure deployment time from 6 hours to 15 minutes
Saved $45K annually through resource optimization identified during Terraform migration
Implemented blue-green deployments across regions for zero-downtime releases
Created infrastructure cost monitoring dashboards showing $8K monthly spend per region
Passed SOC 2 audit with commendation on disaster recovery preparedness
Reduced RTO from 4 hours to 12 minutes (95% improvement)
Built automated region health monitoring with PagerDuty integration
Configured VPC peering and Transit Gateway for secure cross-region communication
Established infrastructure drift detection running daily with automatic remediation