Prioritization and Migration: Wave Planning and Portfolio Assessment
Prioritization and migration of workloads (for example, wave planning)
Prioritization and Migration: Wave Planning and Portfolio Assessment
This guide covers the critical processes for migrating enterprise workloads to AWS at scale, focusing on Content Domain 4 of the SAP-C02 exam. It explores how to assess portfolios, prioritize applications, and structure migration waves.
Learning Objectives
After studying this guide, you should be able to:
- Explain the Mobilize Phase and its role in migration readiness.
- Categorize applications using the 7 Rs of Migration.
- Define Wave Planning and the criteria used to prioritize workloads.
- Distinguish between different data and application migration tools.
- Evaluate Total Cost of Ownership (TCO) for cloud migration business cases.
Key Terms & Glossary
- CMDB (Configuration Management Database): A repository that acts as a data warehouse for information about an organization's IT assets and their relationships.
- Wave Planning: The process of grouping applications into logical groups (waves) to be migrated over a specific timeline.
- Landing Zone: A well-architected, multi-account AWS environment that is a starting point from which you can deploy workloads and applications.
- Migration Hub: A central place to track the progress of application migrations across multiple AWS and partner solutions.
- 7 Rs: The seven common migration strategies (Retain, Retire, Rehost, Relocate, Replatform, Repurchase, Refactor).
The "Big Idea"
Migration is not a single event but a structured journey. Moving thousands of servers requires a "Factory" approach. Instead of a "big bang" migration, organizations use Wave Planning to move small, manageable groups of applications. This minimizes risk, allows for iterative learning, and ensures that the most valuable or easiest "quick wins" are moved first to prove the business case.
Formula / Concept Box
| Concept | Application / Logic |
|---|---|
| Migration Priority | |
| TCO (Total Cost of Ownership) | |
| Wave Size | Typically 10–30 applications per 4–8 week cycle, depending on team velocity. |
Hierarchical Outline
- Phase 1: Assessment
- Portfolio Discovery: Identifying all assets using AWS Application Discovery Service.
- TCO Analysis: Justifying the move to stakeholders.
- Phase 2: Mobilize
- Landing Zone Setup: Using AWS Control Tower to establish security and governance.
- Migration Strategy (7Rs): Assigning a path to every application.
- Wave Planning: Creating the migration schedule.
- Phase 3: Migrate & Modernize
- Execution: Using tools like AWS Application Migration Service (MGN).
- Optimization: Right-sizing and implementing cost-saving models (Savings Plans).
Visual Anchors
The Migration Lifecycle
Prioritization Matrix (Complexity vs. Value)
Definition-Example Pairs
- Rehosting (Lift-and-Shift): Moving an application to the cloud without making any changes to take advantage of cloud capabilities.
- Example: Moving an on-premises SQL Server running on a VM directly to an Amazon EC2 instance using AWS MGN.
- Replatforming (Lift-and-Reshape): Making a few optimizations to the application to achieve some cloud benefit without changing the core architecture.
- Example: Moving an on-premises Oracle database to Amazon RDS for Oracle to reduce management overhead.
- Refactoring (Rearchitecting): Reimagining how the application is architected and developed using cloud-native features.
- Example: Breaking a monolithic Java application into AWS Lambda microservices.
Comparison Tables
The 7 Rs Migration Strategies
| Strategy | Effort | Cloud Benefit | Best For... |
|---|---|---|---|
| Retire | None | High (Cost Saving) | Legacy apps no longer used. |
| Retain | None | Zero | Apps with high compliance or hardware dependencies. |
| Rehost | Low | Low/Medium | Large scale, fast migrations. |
| Replatform | Medium | Medium/High | Reducing DB management overhead. |
| Refactor | High | Maximum | Strategic, high-traffic business apps. |
Worked Examples
Scenario: Planning the First Wave
Context: A company has 500 applications. They need to show success to the board within 3 months.
Application Candidates:
- App A: Internal payroll (Low traffic, mission-critical, high complexity).
- App B: Public Marketing Site (High traffic, low complexity, standalone).
- App C: Legacy Archive (No users, high storage cost).
Step-by-Step Decision:
- Analyze App C: Since it has no users, it should be Retired immediately for instant cost savings.
- Analyze App A: Too complex for a first wave. Failure here would jeopardize the whole program. Schedule for Wave 3.
- Analyze App B: High visibility but low complexity. Ideal for a "Quick Win." Schedule for Wave 1.
Outcome: Wave 1 consists of App B (Rehost) and the decommission of App C.
Checkpoint Questions
- What AWS service is specifically designed to create a multi-account environment with automated guardrails?
- Which of the 7 Rs involves switching to a SaaS model (e.g., moving from on-prem Exchange to Salesforce)?
- Why is a CMDB important during the Application Discovery workstream?
- In Wave Planning, should highly complex applications with many dependencies be moved in the first wave? Why or why not?
[!TIP] Answer Key: 1. AWS Control Tower; 2. Repurchase; 3. To understand dependencies and hardware/software assets; 4. No, they should be moved later once the migration "factory" is established and tested with simpler workloads.
Muddy Points & Cross-Refs
- Rehost vs. Relocate: Rehost usually refers to EC2 (changing the hypervisor), while Relocate refers to moving VMware workloads to VMware Cloud on AWS without changing the hypervisor.
- Data Migration: If you have massive data (PB scale) and limited bandwidth, use AWS Snowball Edge. If you have high bandwidth but need continuous sync, use AWS DataSync.
- Further Study: Review the AWS Cloud Adoption Framework (CAF) for organizational readiness and the Migration Acceleration Program (MAP) for funding and methodology.