🏗️ Project Overview

The objective is to design and implement a hybrid infrastructure where a local on-premises server continues to host critical legacy applications, while scalable services are offloaded to the AWS cloud. This setup supports business continuity, scalability, and disaster recovery.

Secure connectivity between the on-prem network and AWS is established via AWS Site-to-Site VPN or AWS Direct Connect. Docker images are built and tested locally, then pushed to Amazon ECR for deployment to ECS. A read-only replica of the on-prem database is maintained in Amazon RDS, enabling cloud-based analytics and reporting workloads without interfering with the local production system.

All logs are centralized in Amazon CloudWatch, covering both environments for unified observability. Additionally, daily on-prem backups are synchronized to Amazon S3, ensuring durable off-site storage and facilitating disaster recovery.

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🛠️ Technologies and Tools

Category	Tool/Service	Purpose
Version Control	GitHub	Source code repository and CI trigger
Containerization	Docker	Build and test containers locally
Container Registry	Amazon ECR	Host production-ready images
Orchestration	Amazon ECS	Deploy containers in the cloud
Networking	AWS Site-to-Site VPN / Direct Connect	Secure connectivity between on-prem and AWS
Database (On-Prem)	Legacy SQL/NoSQL DB	Hosts core business data
Database (Cloud Replica)	Amazon RDS (read replica)	Sync on-prem DB to the cloud
Monitoring & Logging	Amazon CloudWatch	Unified logging and monitoring
Backup & Recovery	Amazon S3	Off-site storage for daily on-prem backups
Infrastructure as Code	Terraform	Infrastructure deployment and versioning
Security	IAM, Security Groups, VPN Tunnel Keys	Access control and secure networking

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🎯 Goals and Functionality

• ✅ Hybrid Architecture

  • Maintain critical services on-prem
  • Offload scalable workloads to AWS

• ✅ Secure Cloud Connectivity

  • Set up Site-to-Site VPN or Direct Connect for secure access
  • Enable private communication between environments

• ✅ Containerized Workflow

  • Build and test Docker images on-prem
  • Push to ECR for deployment to ECS

• ✅ Database Replication

  • Sync read-only replica of local DB to RDS
  • Offload read-heavy operations to cloud

• ✅ Unified Monitoring

  • Centralize logs from local and cloud into CloudWatch

• ✅ Durable Backup Strategy

  • Automate daily on-prem backup uploads to Amazon S3
  • Ensure off-site storage and disaster recovery readiness

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⚠️ Probable Challenges

Area	Potential Challenge	Suggested Mitigation
Network Reliability	Site-to-Site VPN can experience latency or drops	Use Direct Connect or multi-tunnel VPN with failover
DB Sync Complexity	Ensuring data consistency between on-prem and RDS	Use dedicated replication tools and periodic verification
Cloud Migration Barriers	Legacy apps may not be cloud-ready	Containerize legacy components where feasible or use API gateways
Log Aggregation	Merging logs from disparate systems	Normalize log formats before pushing to CloudWatch
Backup Failures	Upload interruptions or incomplete syncs	Implement verification steps and retry logic
Security Management	Handling different IAM and access models	Implement federated access and use least-privilege policies
Resource Cost Management	Hybrid model can cause unexpected cloud charges	Use billing alerts and resource tagging for cost tracking
Terraform Complexity	Managing state between on-prem and cloud resources	Isolate modules and use remote backends for Terraform state