1.4 Cloud Migration Strategies
Key Takeaways
The AWS Cloud Adoption Framework (CAF) organizes guidance into six perspectives: Business, People, Governance (business-focused) and Platform, Security, Operations (technical-focused).
The 7 Rs of migration are Rehost, Replatform, Refactor, Repurchase, Retain, Retire, and Relocate.
Rehost (lift and shift) is the fastest strategy with the least change; Refactor (re-architect) yields the greatest cloud benefit but the most effort.
AWS Snowball Edge, the last Snow Family device, has been available only to existing customers since November 7, 2025; AWS points new customers to DataSync, AWS Data Transfer Terminal, or Partner solutions.
Migration tools include Migration Hub, Application Migration Service (MGN), Database Migration Service (DMS), and DataSync.
Quick Answer: AWS describes the 7 Rs of migration: Rehost (lift and shift), Replatform (lift, tinker, shift), Refactor (re-architect), Repurchase (buy a SaaS replacement), Retain (keep on-premises), Retire (decommission), and Relocate (move VMware to VMware Cloud on AWS). The right choice depends on business need, timeline, and the cloud benefits you want.
AWS Cloud Adoption Framework (AWS CAF)
The AWS Cloud Adoption Framework (AWS CAF) provides guidance for organizations planning cloud adoption. It organizes guidance into six perspectives, split into business-focused and technical-focused groups.
Business-Focused Perspectives
| Perspective | Focus | Stakeholders |
|---|---|---|
| Business | Ensure cloud investments accelerate business outcomes | CEO, CFO, COO, CIO |
| People | Staffing, culture, and organizational change management | HR, people managers |
| Governance | Governance, risk management, and compliance | CIO, CTO, CFO, CDO |
Technical-Focused Perspectives
| Perspective | Focus | Stakeholders |
|---|---|---|
| Platform | Design and build a scalable, cloud-ready architecture | CTO, architects |
| Security | Confidentiality, integrity, and availability of data | CISO, compliance managers |
| Operations | Run and support cloud services day-to-day | IT operations, support |
On the Exam: Know the six perspectives and which are business (Business, People, Governance) versus technical (Platform, Security, Operations).
The 7 Rs of Migration
1. Rehost (Lift and Shift)
Move applications to the cloud without changes — for example, from on-premises servers to EC2 instances.
- Effort: Low — Benefit: fast migration, immediate savings on data-center operations
- Best for: large-scale migrations with tight timelines
2. Replatform (Lift, Tinker, and Shift)
Move with small optimizations that use cloud capabilities, without changing the core architecture.
- Effort: Low–Medium — Benefit: some cloud optimization without full re-architecture
- Example: migrate self-managed MySQL on EC2 to Amazon RDS
3. Refactor / Re-architect
Redesign the application to be cloud-native using serverless and microservices.
- Effort: High — Benefit: maximum scalability, performance, and cost efficiency
- Example: break a monolith into Lambda + API Gateway + DynamoDB microservices
4. Repurchase (Drop and Shop)
Replace the application with a SaaS product.
- Effort: Medium — Benefit: eliminates maintenance, gains new features
- Example: move from an on-premises CRM to Salesforce
5. Retain (Revisit)
Keep the application on-premises for now, due to compliance, recent investment, or complexity.
- Effort: None (for now) — Best for: apps not yet ready to migrate
6. Retire
Decommission applications discovered to be unused or duplicate during assessment.
- Effort: Low — Benefit: removes unnecessary cost and complexity
7. Relocate (Hypervisor-Level Lift and Shift)
Move infrastructure to AWS without buying new hardware, rewriting apps, or changing operations — specifically migrating VMware workloads to VMware Cloud on AWS.
- Effort: Low — Best for: organizations heavily invested in VMware
Migration Tools and Services
| Service | Purpose |
|---|---|
| AWS Migration Hub | Central place to track migration progress across tools |
| AWS Application Migration Service (MGN) | Automate lift-and-shift server migrations |
| AWS Database Migration Service (DMS) | Migrate databases with minimal downtime |
| AWS Schema Conversion Tool (SCT) | Convert schemas between database engines |
| AWS DataSync | Automated online data transfer between on-premises and AWS storage |
| AWS Snow Family | Physical devices for offline data transfer (Snowball Edge; existing customers only since November 7, 2025) |
| AWS Transfer Family | Managed SFTP, FTPS, and FTP into AWS |
AWS Snow Family for Data Migration
For datasets too large to move over the network in a reasonable time, AWS has offered physical data transfer devices under the Snow Family. The lineup kept shrinking: AWS Snowmobile (the exabyte-scale truck) was retired in 2024, AWS Snowcone was discontinued, and since November 7, 2025, AWS Snowball Edge is available only to existing customers, so AWS no longer offers any Snow Family device for new customers to order. For new customers, AWS points to AWS DataSync for online transfers, AWS Data Transfer Terminal for secure physical transfers, or AWS Partner solutions, and to AWS Outposts for edge computing.
| Device (existing customers only) | Storage / Compute | Use Case |
|---|---|---|
| Snowball Edge Storage Optimized (210 TB) | ~210 TB NVMe SSD, 104 vCPUs, 416 GB RAM | Large data-center migrations and high-capacity transfer |
| Snowball Edge Compute Optimized | Up to 104 vCPUs, 416 GB RAM, NVMe SSD | Edge computing plus data transfer in disconnected environments |
On the Exam: The online CLF-C02 exam guide no longer lists the Snow Family among its in-scope services or its migration examples (the older PDF guide mentioned AWS Snowball). If an older practice question asks which AWS offering ships data on a physical device, the answer is still AWS Snowball Edge, but for a new customer today AWS recommends DataSync, AWS Data Transfer Terminal, or a Partner solution instead.
Choosing a Strategy
The 7 Rs trade speed against long-term benefit. Rehost is fastest but gains the least cloud optimization; Refactor delivers the most cloud-native benefit but takes the most effort. Many organizations rehost first to exit the data center quickly, then replatform or refactor key workloads over time.
Mapping the 7 Rs to Effort and Benefit
A quick way to reason about the 7 Rs on the exam is to picture a spectrum from least change to most cloud benefit. Retire and Retain require almost no migration work. Rehost and Relocate move workloads quickly with minimal change but gain limited cloud-native optimization. Replatform adds light optimization (such as moving to a managed database). Repurchase swaps the whole application for a SaaS product. Refactor sits at the far end — the most effort, but the greatest scalability, performance, and cost benefit.
When a question stresses "fastest" or "no code change," lean toward Rehost; when it stresses "fully take advantage of cloud-native features," lean toward Refactor.
A company wants to move its on-premises application to AWS as quickly as possible without making any code changes. Which migration strategy should they use?
Rehost
Replatform
Refactor
Repurchase
Which AWS service provides a centralized location to track the progress of application migrations across multiple AWS and partner tools?
AWS Migration Hub
AWS CloudFormation
AWS Config
AWS CloudTrail
Which AWS offering moves data to AWS by shipping a physical storage device, for datasets that would take more than 60 days to send over the network?
AWS Direct Connect
AWS DataSync
AWS Snowball Edge
Amazon S3 Transfer Acceleration
The AWS Cloud Adoption Framework (CAF) has six perspectives. Which are the THREE business-focused perspectives?
Business, Security, Operations
Business, People, Platform
Platform, Security, Operations
Business, People, Governance
An organization is heavily invested in VMware and wants to move those virtual machines to AWS without rewriting applications or changing operations. Which of the 7 Rs applies?
Relocate
Refactor
Repurchase
Retire
Sections you finish are checked off in the contents.