The Microsoft Cloud Adoption Framework (CAF) provides structured, prescriptive guidance for moving on-premises or other-cloud workloads to Azure. Within CAF, the Migrate methodology translates a high-level cloud adoption plan into an actionable migration plan that defines workload prioritization, migration sequencing, data transfer paths, and rollback procedures. Evaluating a migration solution means matching each workload to a migration strategy and to the right tooling, grounded in a business driver rather than technical preference. CAF defines the migration strategies as the "Rs": Retire, Retain, Rehost, Replatform, Refactor, Rearchitect, Rebuild, and Replace. A business driver (the gap between a workload's current and desired state) determines the strategy. Rehost is a fast, low-risk like-for-like move (on-premises servers or AWS EC2 to Azure Virtual Machines, PaaS to PaaS) chosen when there is no near-term modernization need. Replatform moves to PaaS such as Azure App Service or Azure SQL Database with minimal code changes. Refactor and Rearchitect modernize code or architecture, Rebuild creates a cloud-native solution, Replace adopts SaaS, and Retain or Retire keep or decommission a workload. Azure Migrate handles discovery and assessment, while data transfer uses ExpressRoute, VPN, or Azure Data Box for large offline datasets. CAF is organizational planning guidance, not a migration execution engine. It tells you how to structure and sequence a migration but does not perform the move itself; tools like Azure Migrate, Azure Database Migration Service, and Azure Arc do the technical work. For post-migration architecture quality and optimization, the Azure Well-Architected Framework applies instead, and the Azure Architecture Center provides service-mapping and design patterns. Within the Design migrations section, CAF anchors the recommendation logic: choose the lowest-risk strategy that satisfies the business driver, sequence non-production and simple workloads before critical ones, and keep dependent components in the same migration wave.
CAF organizes guidance into seven methodologies (Strategy, Plan, Ready, Adopt, Govern, Secure, Manage), and the Migrate guidance under Adopt produces a migration plan covering sequencing, data paths, and rollback.
Rehost is a like-for-like IaaS-to-IaaS or PaaS-to-PaaS move for stable workloads needing no modernization within roughly two years, while Replatform moves to PaaS like Azure App Service or Azure SQL Database with minimal code changes.
The chosen migration strategy must follow from a business driver, and Microsoft recommends rehost or replatform for most workloads to minimize risk, completing the migration first and optimizing later.
Data migration path selection prefers ExpressRoute when available, VPN as the secure fallback, and Azure Data Box for large offline datasets that should not traverse the network.
Sequencing migrates non-production environments and simpler low-risk workloads first, groups directly dependent components into the same wave, and schedules critical systems for later waves after demonstrating success.
Retain workloads use Azure Arc for unified management from Azure when regulatory, latency, or dependency constraints prevent migration.