Tamil Nadu Finance Department – WAMIS 2.0
Migration and Modernization of WAMIS Financial Management System on AWS
Project Overview
The Tamil Nadu Finance Department manages the state's financial operations through its core financial management system, WAMIS. Previously hosted in an on-premises environment, the system faced challenges related to performance, reliability, security, and scalability.
The WAMIS 2.0 modernization initiative required a secure, scalable, and highly available environment to support multiple departmental modules, high user concurrency, and centralized financial data management.
The Finance Department partnered with Ilios Digital, an AWS Partner, to migrate and modernize the WAMIS application using Amazon Web Services (AWS). The engagement focused on improving application availability, strengthening security, automating operational activities, and establishing disaster recovery capabilities.
The project followed the AWS Migration Acceleration Program (MAP), covering the Assess, Mobilize, and Migrate & Modernize phases. The engagement delivered a secure, three-tier architecture using AWS services, automated backups, centralized monitoring, and disaster recovery in a secondary AWS Region.
Project Objectives
Modernize the legacy WAMIS application using AWS services.
Support growing user demand across multiple departmental modules.
Improve application availability, performance, and reliability.
Strengthen security and governance to meet government requirements.
Automate backups, monitoring, and routine operational activities.
Establish disaster recovery capabilities in a secondary AWS Region.
Reduce manual operational effort and optimize AWS resource utilization.
Solution Overview
Ilios Digital delivered a migration and modernization engagement for WAMIS 2.0 by establishing a secure AWS environment with a three-tier architecture.
The solution includes Amazon Virtual Private Cloud (Amazon VPC) for network isolation, Amazon Elastic Compute Cloud (Amazon EC2) for application workloads, and Amazon Relational Database Service (Amazon RDS) for PostgreSQL database management.
Additional AWS services provide load balancing, shared storage, security monitoring, automated backups, and disaster recovery. AWS Elastic Disaster Recovery (AWS DRS) replicates application servers to a secondary AWS Region to support recovery during regional disruptions.
AWS Migration Acceleration Program (MAP) Phases:
Assess
- Evaluated the existing application, database, networking, storage, and security requirements.
- Conducted workload assessment and dependency analysis.
- Prepared a Total Cost of Ownership (TCO) assessment using AWS Pricing Calculator.
Mobilize
- Established the AWS Landing Zone and network architecture.
- Configured security controls, identity management, and centralized logging.
- Prepared the AWS environment for application and database migration.
Migrate & Modernize
- Migrated application workloads to Amazon EC2.
- Implemented a three-tier architecture.
- Migrated PostgreSQL database workloads.
- Configured automated backups, monitoring, security controls, and disaster recovery.
- Completed application testing, production cutover, and stabilization.
Architecture Overview
Amazon VPC
Network Isolation and Connectivity
Provides isolated networking for WAMIS application workloads.
Uses public and private subnets across two Availability Zones.
Includes route tables, Internet Gateway, NAT Gateway, and Network Access Control Lists (NACLs).
Security Groups and IAM policies control access to AWS resources.
Amazon EC2
Application and Compute Services
Hosts WAMIS web application components, user interface, backend services, Works Management, and Management Information System (MIS) modules.
Provides separate application and supporting service workloads.
Includes a jump server for secure administrative access.
Supports Redis caching and Glowroot Application Performance Monitoring (APM).
Distributes application workloads across two Availability Zones.
Amazon RDS for PostgreSQL
Managed Database Services
Hosts WAMIS transactional database workloads.
Uses Multi-AZ deployment for database availability and automatic failover.
Includes a read replica for MIS and reporting workloads.
Automated backups and point-in-time recovery support data protection.
Amazon EFS
Shared File Storage
Provides shared file storage across application servers.
Uses mount targets across Availability Zones.
Supports application file access and shared workloads.
Amazon S3
Object and Backup Storage
Stores application logs, deployment artifacts, configuration backups, and static files.
Supports durable storage and lifecycle policies.
Retains access logs for auditing and analysis.
Elastic Load Balancing
Application Traffic Distribution
Distributes incoming application traffic across Availability Zones.
Performs health checks on application targets.
Improves application availability and traffic distribution.
AWS WAF and AWS Network Firewall
Security Protection
AWS WAF protects application access against common web exploits.
AWS Network Firewall provides network traffic inspection and filtering.
Supports additional security controls for application workloads.
AWS Identity and Access Management
Access Control
IAM roles and policies enforce least-privilege access.
AWS Secrets Manager manages application credentials and secrets.
Encryption protects data at rest and in transit.
Monitoring and Logging
Operational Visibility
Amazon CloudWatch provides real-time monitoring, metrics, dashboards, and alerts.
AWS CloudTrail records AWS API activity for auditing.
Amazon S3 stores access logs and operational records.
AWS Elastic Disaster Recovery
Regional Recovery
Replicates application servers to a secondary AWS Region.
Enables recovery instances to be launched during regional disruptions.
Supports recovery in minutes with recovery points measured in seconds.
A PostgreSQL read replica in the disaster recovery environment provides additional database recovery capability.
Project Delivery Approach
The project was executed through six Agile sprints and four migration waves.
Wave 1 – Foundation Setup
- AWS Landing Zone establishment.
- Amazon VPC, subnet, routing, and connectivity configuration.
- IAM, Security Groups, GuardDuty, CloudTrail, and AWS Config setup.
Wave 2 – Application Migration
- Amazon EC2 provisioning.
- Application deployment and configuration.
- Load balancing and application connectivity setup.
Wave 3 – Database Migration
- Amazon RDS for PostgreSQL configuration.
- Database migration and validation.
- Read replica and backup configuration.
Wave 4 – Testing and Production Go-Live
- Application integration testing.
- Security validation and monitoring configuration.
- Production cutover and stabilization.
- Go-Live documentation and operational handover.
Business Impact and Outcomes
The WAMIS 2.0 modernization delivered measurable improvements in system availability, operational efficiency, and disaster recovery readiness.
System Availability – 99.95% Uptime
The Multi-AZ three-tier architecture improved availability for critical financial workloads, achieving 99.95% system uptime.
Operational Efficiency – 40% Reduction
Automated backups, centralized monitoring, and simplified maintenance reduced manual operational effort by 40%.
Scalability and Modernization
The monolithic application was replaced with a modular three-tier architecture comprising a jump server, Amazon EC2 application tier, and PostgreSQL database tier.
Security and Governance
Implemented network isolation, least-privilege IAM access, encryption, Amazon GuardDuty, AWS CloudTrail, AWS Config, and Amazon Inspector to strengthen security and auditability.
Disaster Recovery
Established AWS Elastic Disaster Recovery in a secondary AWS Region, enabling application recovery in minutes with recovery points measured in seconds.
Cost Assessment
Completed a TCO assessment using AWS Pricing Calculator, establishing a projected annual AWS run rate of approximately USD 140,000.
Delivery and Go-Live
Completed six Agile sprints and four migration waves between September 20, 2025, and January 29, 2026, with production delivery and Go-Live documentation.
Key Takeaways
- ✓Modernized a critical government financial management application using AWS services.
- ✓Achieved 99.95% system uptime through a Multi-AZ architecture.
- ✓Reduced manual operational effort by 40% through automation and centralized monitoring.
- ✓Established disaster recovery in a secondary AWS Region.
- ✓Improved security, governance, and operational visibility.
- ✓Delivered the modernization through six sprints and four migration waves.