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Cloud Infrastructure

Cloud Migration Done Right: Zero-Downtime Strategy for Financial Services

Calimatic Team
7 min read

Migrating critical financial services infrastructure to the cloud requires meticulous planning, security considerations, and zero tolerance for downtime. Here's how we executed a flawless migration that exceeded all expectations.

The Challenge

Our client, a financial services firm processing 50,000+ daily transactions, needed to migrate from on-premise infrastructure to AWS while maintaining:

  • 100% uptime during business hours
  • SOC 2 Type II compliance
  • Sub-100ms API response times
  • Complete audit trails for all transactions
  • Real-time data synchronization

Migration Strategy

Phase 1: Assessment & Planning (4 weeks)

  • Complete infrastructure audit and dependency mapping
  • AWS architecture design with multi-AZ redundancy
  • Security and compliance framework setup
  • Disaster recovery and rollback procedures

Phase 2: Parallel Infrastructure (6 weeks)

  • Set up AWS environment with IaC (Terraform)
  • Configure VPCs, subnets, and security groups
  • Implement real-time data replication
  • Load testing and performance validation

Phase 3: Gradual Cutover (8 weeks)

  • Route 10% of traffic to AWS for validation
  • Incremental traffic increase (10% → 25% → 50% → 100%)
  • Continuous monitoring and performance tuning
  • Decommission on-premise infrastructure

Results

  • Zero downtime: 100% uptime maintained throughout migration
  • 60% cost reduction: From $180K/year to $72K/year in infrastructure costs
  • 3x performance improvement: API response times dropped from 250ms to 85ms
  • 99.99% availability: Exceeding previous 99.5% SLA
  • Scalability: Can now handle 10x traffic without infrastructure changes

Ready to Start Your Success Story?

Let's discuss how Calimatic can help you achieve similar results.