4.1 Migration Assessment
Migration Strategies (The 7 Rs) - Cheatsheet
| Strategy | Also known as | Description | Use Case |
|---|
| Rehost | Lift and Shift | Automate moving VM to EC2. | Speed is critical. No code changes. |
| Replatform | Lift, Tinker, Shift | Move to Managed Service (RDS, Elastic Beanstalk). | Reduce admin overhead. Optimization. |
| Refactor | Re-architect | Rewrite app (Microservices, Serverless). | Cloud-native features. Scaling/Performance required. |
| Repurchase | Drop and Shop | Switch to SaaS (Salesforce, Workday). | Replace legacy software entirely. |
| Relocate | Hypervisor Shift | VMware Cloud on AWS. | Move vSphere VMs without conversion. |
| Retain | Do Nothing | Keep as-is. | App not ready or dependency issues. |
| Retire | Decommission | Shut down. | Redundant apps. |
Assessment Services
AWS Application Discovery Service
- Function: Discovery of on-prem servers.
- Agentless: Uses OVA file in VMware. Collects config and performance.
- Agent-based: Installs on OS (Linux/Windows). clearer dependency mapping and process-level details.
AWS Migration Hub
- Function: Tracks the status of migrations across multiple tools (DMS, MGN, SMS).
- Home Region: You pick a “Home Region” to store status data (status data is regional; migrations can be anywhere).