Migration of Legacy IT Application to Azure

13 FEB 2018

Client

Client is a one of leading provider of payment gateway services that allows virtual swiping of credit cards securely. They offer online payment processing services for various merchants and suppliers worldwide.

Clients concocted a thought

The client’s current application was used by many of its customers to perform online credit card payments from around the world. It handles processing, verification and reporting of payment tasks securely and affectively. Current application was built using ASP .NET framework. It was hosted on a single instance Windows 2003 32-bit OS server and was not PCI compliant. The system used a standard Microsoft SQL server 2005 database for storage and no documentation was available regarding the DLLs used. The Current system lacked the capability to scale on-demand and control system downtime. It was not supporting the latest security and high capacity infrastructure standards as the system had not been upgraded for 15+ years. Therefore, the client aimed at transitioning their legacy system to Azure via IaaS platform. They wanted to revamp the system in order to offer a more advanced and secure payment platform to their customers. The other key reasons that strengthened their decision to choose IaaS migration via Azure was to reduce maintenance requirements, maximize performance, minimize costs, achieve zero downtime and zero data loss.

What we proposed

Star Knowledge team conducted a detailed study which focused on understanding the legacy system  architecture and deployment setup. The study helped in abstracting the complexity of the existing system and in re-engineering the system architecture that is compatible with cloud infrastructure. Azure IaaS platform is cost-effective & flexible and delivers resilience, performance, and security required to host applications. Deploying the legacy system using Azure IaaS platform reduces the required physical infrastructure and provides zero downtime.

The existing system lacked the capability to cope, perform and handle increased workload. This challenge was achieved by reconfiguring the Web and Database servers that were handling the legacy system. Our Azure migration experts have devised a modern architecture with server and database systems as separated entities. They introduced a pair of availability sets that consisted of two VMs each. First availability set included a pair of Web Server VMs that act as Load Balance system to balance the incoming load between the two cloud VMs. The second availability set consisted of 2 SQL VMs, the database VM1 and a mirrored database of VM1. This database pattern with 2008 R2 SQL VMS served to achieve highly redundant, zero data loss system. The two availability sets ensured to provide 99.95% on-demand availability of the system. Thus, supporting scalability and zero downtime for the modern architected system through this migration process. Few other Azure migration challenges went in discovering and understanding the DLL dependencies, establishing the Azure Virtual Network, setting up Azure Backup Service, that were used in the existing system.

The existing payment processing application was not PCI compliant for database security. As Azure is one of the few cloud platforms that is PCI compliant, it was easy to overcome this challenge. Using simple Azure Back-up solution, we have backed-up the VM databases in the other data center at different location and achieved 35% increased computing power. Azure IaaS platform and Star Knowledge’s migration strategy helped in the smooth transitioning of the existing legacy system to Azure. With the migration solution, the client was able to reduce on-premise infrastructure costs overhead by more than 75% with zero maintenance costs overhead.

Results & benefits obtained

• Availability of OnDemand Modernized system that was scalable and support zero data loss and no downtime
• Reduced infrastructure cost
• More robust and secured
• Highly Flexible

Technologies used

• Microsoft Azure IaaS
• Azure Virtual Network
• Azure DNS
• Azure Backup Service
• Azure Storage