AWSifying a COTS Application and Delivering Real Business Value
Introduction
This article describes my experience as part of the Systems Integrator (SI) organization in cloudifying a complex COTS application on AWS that is used to manage cohorts and capture hemodynamic data for pre-clinical study interventions in the cardiovascular disease domain.
The initiative involved three distinct entities, the client operating the application, an external COTS vendor that had only ever deployed the product on traditional on premises infrastructure, and my organization responsible for driving the cloud transformation. The vendor had no prior experience or confidence in running the application on the cloud.
Understanding the Core Challenges
The legacy COTS application faced multiple technical and operational challenges that impacted reliability, security, and user experience. Key issues included:
- Inadequate Monitoring: Server monitoring was minimal, making it difficult to detect disk failures or resource issues, which risked system reliability and data integrity.
- Insufficient Data Backup: Backups of virtual machines were stored on the same physical hardware, creating a single point of failure and risking irrecoverable data loss in case of a disaster.
- Unreliable Power Supply: The absence of an uninterrupted power supply left servers vulnerable to outages, which could cause service disruptions or data corruption.
- Security Vulnerabilities: Servers were running an outdated OS, increasing exposure to known threats, while numerous firewall rules reduced overall security effectiveness.
- Delayed Remote Access for Vendor: Remote access for the external COTS vendor, essential for updates and troubleshooting, had been pending for years, slowing issue resolution.
- User Management Challenges: Users needed to manually re enable Virtual Lab access every 8 hours or after IP changes, and recurring directory and access issues hindered productivity and user experience.
The most significant challenge was not technical but psychological. The external COTS vendor lacked confidence that the application could run on the cloud, while leadership within my own organization viewed it as a dead rubber. What many perceived as a closed chapter, I saw as an opportunity to challenge assumptions and demonstrate that the application was cloudifiable.
Solution Approach
Building on the earlier mindset and confidence barriers, the initial focus was to bring leadership within my organization into confidence, followed by aligning the COTS vendor on cloud feasibility. Once all three parties shared a common understanding and trust in the direction, the path forward became structured and actionable. The solution approach was first discussed and aligned jointly with the client and the external COTS vendor.
- Joint Assessment and Strategy Definition: To conduct a holistic assessment together with the external COTS vendor to understand application architecture, dependencies, constraints, and support boundaries, and to define a comprehensive AWS migration strategy.
- Secure Cloud Foundation: To provision a secure AWS infrastructure using infrastructure-as-code, aligned with DevSecOps best practices to ensure consistency, security, and auditability from day one.
- Monitoring and Operational Readiness: To implement robust monitoring, observability, and post migration application and platform support to ensure operational stability and faster issue resolution.
- Application and Database Deployment: To install the COTS application along with its associated Microsoft SQL Server database on Amazon EC2 , respecting vendor recommendations and domain specific requirements.
- Testing and Validation: To execute rigorous testing phases including regression, functional, non functional, performance testing, followed by user acceptance testing to validate readiness for production.
- Environment Strategy: To provision two environments for the migration, Test and Production, hosted within a single AWS account to balance isolation, governance, and operational simplicity.
High-Level Target Architecture Overview
Implementation Journey
The implementation phase brought together three key entities, the client, the COTS vendor, and my organization, working in close collaboration. With alignment already established during the solution approach, this phase focused on translating shared intent into execution, guided by a clear target architecture and well defined responsibilities.
- Joint Assessment Outcomes: A detailed joint assessment with the external COTS vendor highlighted that long standing remote connectivity issues were primarily driven by policy and process differences rather than technical limitations. Based on these findings, it was jointly agreed that both the application and the Microsoft SQL Server database would follow a Lift and Shift approach, with no database replatforming.
- Secure Infrastructure Provisioning: My organization provisioned the secure AWS foundation using Infrastructure-as-Code (IaC) with Terraform. CI/CD pipelines were set up following a GitOps approach to ensure repeatability, traceability, and controlled changes across environments.
- Application and Database Deployment: The external COTS vendor installed the application and its associated Microsoft SQL Server database on Amazon EC2 instances within private subnets, aligned with the approved target architecture.
- Connectivity and Access Model: Secure access was enabled using a bastion host, controlled network routing, and identity integration, ensuring that vendor and client access requirements were met without compromising security posture.
- Observability and Monitoring: Enhanced monitoring and logging were implemented using Amazon CloudWatch, providing better visibility into system health, performance, and operational events.
- Backup and Recovery: Regular and automated backups were configured using AWS Backup, significantly improving data protection and recovery readiness compared to the previous setup.
- Shift Left Operations Readiness: A shift-left operating model was adopted by assigning a dedicated engineer from the early stages of the migration. This ensured hands on exposure throughout implementation, enabling the engineer to be fully prepared to take over day to day operations smoothly once the application went live.
Outcomes and the Future Ahead
With the application successfully transitioned to AWS, the focus shifted from migration execution to stable post migration operations and continuous improvement. What began as a high risk initiative evolved into a reliable production platform that now supports business continuity, growth, and future innovation.
- AWSified and Production Ready: The COTS application is now fully operational on AWS, running in a controlled, monitored, and supportable production environment aligned with enterprise operational standards.
- Scalable and Reliable Operations: The platform can handle increasing users and growing data volumes without instability, enabling consistent performance as demand evolves.
- Security Leveled Up: The overall security posture has improved through stronger network isolation, identity and access controls using AWS IAM, hardened infrastructure, and continuous monitoring. Ongoing efforts include further reducing the attack surface by transitioning from a bastion host based access model to AWS Systems Manager Session Manager.
- Seamless Connectivity: Secure and predictable access has replaced earlier connectivity challenges, reducing operational friction for users and the external COTS vendor.
- Agentic AI on the Horizon: With a stable operational baseline established, attention is shifting to optimizing day to day operations by exploring advanced capabilities such as Agentic AI patterns using Amazon Bedrock AgentCore to further support users and operational workflows.
Conclusion
While Lift and Shift is often viewed as a simple migration approach, it can quickly become complex when vendor uncertainty, strict domain requirements, and multiple stakeholders are involved. When approached with a positive attitude, the right mindset, and strong architectural and delivery discipline, such initiatives deliver real business value, strengthen trust across all parties, and create a solid foundation for future innovation.
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This journey reinforced that cloud transformations are as much about people and confidence as they are about technology. With the right intent and persistence, even applications once considered immovable can be repositioned to support long term resilience and growth.
Sometimes, the biggest risks bring the best stories!
