Enterprise Guide to Multi-Cloud Migration
1. Assessment & Portfolio Discovery
Before moving a single byte of data, audit your existing infrastructure. Categorize workloads using the 6 Rs of migration: Rehost, Replatform, Refactor, Retire, Retain, or Re-purchase.
Map application interdependencies to define your migration waves. Group systems that share frequent database connections or low-latency dependencies to avoid network egress costs during the transition phases.
2. Setting up Secure Landing Zones
Establish a multi-account structure on your target cloud platforms (AWS Organizations, GCP Folders) with strict root-account locks.
Configure centralized logging (CloudTrail, Stackdriver), federated single sign-on (SSO), and VPC peering with transit gateways. This forms the secure foundation where all migrated services will reside.
3. Data Migration and Replication
For large databases, utilize continuous replication tools to mirror data to the cloud in real-time.
Execute a final sync cutover during low-traffic windows, switching CDN routing to point to the new cloud nodes. Keep the old system running in read-only shadow mode for 7 days to facilitate simple rollbacks if needed.