About the client

Our client is one of the largest banks in Eastern Europe. It uses a sophisticated digital solution featuring a multi-purpose payment system that combines cashier, accountant, clerk, and administrator workplaces. In addition, the application service is an engine for self-service kiosk machines. The system processes millions of transactions every month, aggregates, and keeps track of a complete banking day workflow. The number of payments can significantly vary during a month – at the beginning of a month, the load can be 5-8 times larger than the daily average.

Challenge

The client’s request was to partly migrate on-premise infrastructure to the cloud.

As per the customer’s requirements, the application services should have been hosted in the cloud for cost reduction and efficient scaling. The database cluster should have been replicated in the cloud to cut costs of disaster recovery infrastructure and reduce downtime, but the write nodes should have remained in the local data center.

In detail, the project scope included three key deliverables:
– to migrate 4 large Microsoft Hyper-V application services to AWS for automatic scale in/out;
– to replicate 4-node Microsoft SQL Server DB cluster to AWS (while the nodes must have remained in the client’s datacenter);
– to migrate 2-node DWH and Reporting Service machine to AWS.

During the implementation, the team had to tackle certain challenges associated with:
– diverse infrastructure, complex security rules, thousands of clients over LAN;
– legacy application (Borland C++). Due to that, there was the possibility of instance failures, as well as no automatic disaster recovery;
– complex database with intense usage of triggers, transactions, and stored procedures;
regular spikes in the workload.

Solution

The successful project implementation was secured by the use of the following technologies:
– AWS Migration Service helped migrate application services;
– The VM incremental backups ensured iterative step-by-step migration with an excessive testing phase;
– The EC2 auto-scaling groups enabled a cost-effective automated scale in/out approach;
– CloudEndure Disaster Recovery provided an easy way to establish a bridge between the on-premise SQL Server cluster and backup replicas;
– VPC subnets, security groups, and ACLs ensured quick and secure infrastructure; configuration for further operational usage.

Technologies

Result