Cloud Migration Guide
The 6 Rs of Cloud Migration
Rehost (Lift & Shift)
Move as-is to cloud VMs. Fastest path, least optimization. Good for rapid migration.
Replatform
Minor optimization without changing core architecture. E.g., move to managed DB.
Refactor (Re-architect)
Redesign for cloud-native (microservices, serverless). Most value, most effort.
Repurchase
Replace with SaaS alternative. E.g., on-prem CRM → Salesforce.
Retire
Decommission unused or obsolete systems. Reduces cost and complexity.
Retain
Keep on-premises (compliance, latency, cost). Hybrid cloud approach.
Migration Phases
| Phase | Activities | Duration |
|---|---|---|
| 1. Assess | Inventory, TCO analysis, 6R classification | 2–4 weeks |
| 2. Plan | Migration plan, landing zone, training | 4–8 weeks |
| 3. Migrate | Pilot migration, then waves | Months |
| 4. Optimize | Cost, performance, security tuning | Ongoing |
Common Pitfalls
- ⚠️ Lifting and shifting without optimizing = paying cloud prices for on-prem architecture
- ⚠️ Underestimating data transfer costs (especially egress)
- ⚠️ Not setting up cost monitoring before migration
- ⚠️ Skipping security hardening (shared responsibility model)
- ⚠️ No rollback plan for production migration