Cloud Migration Template for Agile Teams

Small migrations (under 10 workloads) typically take 2-4 months. Medium migrations (10-50 workloads) run 4-9 months. Large enterprise migrations with hundreds of workloads can take 12-24 months. The biggest variable is not the number of workloads but the complexity of dependencies between them. Tightly coupled systems require more coordination and longer testing windows per wave.

Phased migration is almost always the right approach. Big-bang migrations concentrate risk into a single event with no fallback position. Phased migrations let you learn from early waves, refine your process, and contain blast radius when something goes wrong. The exception is very small environments (under 5 workloads with minimal dependencies) where the overhead of managing phases exceeds the risk of a single cutover.

Use a parallel-run strategy. Deploy the application in the cloud environment, sync data between source and target using replication, then switch traffic at the DNS or load balancer level. This approach requires your application to support running in two locations simultaneously, which means stateless compute and externalized session management. The [zero-downtime migration template](/templates) covers this pattern in detail.

Underestimating dependency complexity. Teams catalog their workloads but miss the invisible connections between them: shared databases, file system mounts, hardcoded IP addresses, service discovery mechanisms, and implicit network assumptions. When these surface during migration, they force unplanned rework and timeline extensions. Spend more time on dependency mapping than you think you need.

Set up cost alerts before migration, not after. Tag every resource with project, team, and environment labels. Use reserved instances or savings plans for predictable workloads. Review cost reports weekly for the first three months. Shut down non-production environments outside business hours. Most teams see costs 20-40% higher than projections in month one, then optimize down to target by month three.