Cloud Migration Checklist 2026: A Step-by-Step Enterprise Guide

Pre-Migration: Discovery & Assessment

Every failed cloud migration starts with inadequate discovery. Before moving a single server, inventory every application, dependency, data flow, and integration point. Classify workloads by migration complexity and business criticality.

• Complete application inventory with dependency mapping
• Performance baselines for every workload (CPU, memory, I/O, latency)
• Data classification: public, internal, confidential, regulated
• License audit: which software permits cloud deployment?
• Network architecture documentation including VPN, firewalls, DNS

Migration Strategy Selection

Gartner's 6 R's guide strategy: Rehost (lift-and-shift), Replatform (managed services), Repurchase (SaaS), Refactor (cloud-native), Retire (decommission), Retain (keep on-prem). Most enterprises use a portfolio approach — not one strategy for everything.

Lift-and-shift gets you to cloud fastest but misses optimization opportunities. Refactoring costs more upfront but delivers 30–50% long-term savings through auto-scaling, managed services, and reduced operational overhead.

Security & Compliance Preparation

Cloud security is a shared responsibility. Define IAM policies, network segmentation (VPCs, security groups), encryption at rest and in transit, and logging/monitoring before migration — not after an incident.

For Sri Lankan government and financial clients, ensure cloud regions meet data residency requirements. Document compliance mappings (ISO 27001, PCI-DSS) for audit readiness.

Execution: Phased Migration

Never migrate everything at once. Start with non-critical workloads to validate your runbooks. Progress to staging environments, then production with rollback plans at every stage.

• Phase 1: Dev/test environments and internal tools (weeks 1–4)
• Phase 2: Non-critical production workloads with parallel running (weeks 5–8)
• Phase 3: Critical systems with blue-green or canary deployment (weeks 9–16)
• Phase 4: Decommission on-prem infrastructure after 30-day stability period

Post-Migration Optimization

Migration isn't the finish line — it's the starting line. Right-size instances within 30 days using actual utilization data. Implement auto-scaling, reserved instances for predictable workloads, and spot instances for batch processing. Set up cost alerts and monthly FinOps reviews.