Executive Summary
Cloud migration is not simply about moving applications from on-premises infrastructure to the cloud. Enterprises must determine which workloads should move, which need modernization, and which should remain or be retired.
The 6 Rs of cloud migration – Rehost, Replatform, Repurchase, Refactor, Retain, and Retire – provide a practical framework for these decisions.
- Different workloads require different migration approaches.
- Rehosting prioritizes speed; refactoring prioritizes modernization.
- Not every application should migrate.
- A decision matrix helps enterprises evaluate workloads consistently.
- Effective cloud migration services should align migration with long-term technology and business objectives.
Introduction
Enterprises migrate to the cloud to improve scalability, agility, resilience, and operational efficiency. But the biggest challenge is often deciding what to do with each application.
Should a legacy application move unchanged? it should be optimized for cloud infrastructure? Should a SaaS platform replace it? Or should the application be retired?
Applying one migration approach to an entire application portfolio can increase cost and risk. The 6 Rs framework helps enterprises make workload-specific decisions based on business value, technical condition, dependencies, and modernization objectives.
Planning your cloud transformation? Talk with INT.’s experts to assess your application portfolio, choose the right migration approach, and build a secure, scalable cloud roadmap.
What Are the 6 Rs of Cloud Migration?
The 6 Rs provide six possible paths for an enterprise workload:
Rehost → Replatform → Repurchase → Refactor → Retain → Retire
1. Rehost
Rehosting, often called “lift and shift,” moves an application to cloud infrastructure with minimal changes.
It is useful when migration speed is important, the application remains valuable, and significant code changes are unnecessary.
The advantage is faster migration. However, simply moving an application may not unlock the full benefits of cloud-native technologies.
2. Replatform
Replatforming makes selected improvements without fundamentally redesigning the application.
For example, an enterprise might move a database to a managed cloud service or containerize an application.
It provides a middle ground between the speed of rehosting and the deeper modernization involved in refactoring.
3. Repurchase
Repurchasing means replacing an existing application with another product, commonly a SaaS platform.
An organization might replace an internally hosted CRM, HR, finance, or collaboration application with a cloud-based alternative.
Enterprises should evaluate data migration, integrations, licensing, customization, and user adoption before choosing this approach.
4. Refactor
Refactoring involves redesigning an application to take greater advantage of cloud-native technologies.
This may involve:
- Microservices
- Containers
- Serverless computing
- Managed cloud databases
- API-first architecture
Refactoring requires greater investment but can improve scalability, resilience, and maintainability. It is especially relevant when a broader cloud modernization strategy includes transforming strategically important applications.
5. Retain
Some applications should remain in their current environment.
Reasons may include regulatory requirements, technical dependencies, hardware constraints, contractual commitments, or limited near-term migration value.
Retaining an application should be a deliberate decision, with the workload periodically reassessed.
6. Retire
Some applications no longer deliver sufficient business value.
Retiring redundant or obsolete systems can reduce infrastructure costs, licensing expenses, maintenance effort, security exposure, and application complexity.
Cloud migration is therefore also an opportunity to simplify the enterprise technology portfolio.
How Do You Choose the Right Cloud Migration Strategy?
A decision matrix helps enterprises evaluate applications consistently rather than selecting migration approaches based on technical preference alone.
| Application Scenario | Recommended Strategy |
| Stable application requiring rapid migration | Rehost |
| Needs limited cloud optimization | Replatform |
| Can be replaced by a SaaS product | Repurchase |
| Strategic application requiring modernization | Refactor |
| Cannot or should not move yet | Retain |
| Provides little ongoing business value | Retire |
Organizations should also evaluate business criticality, technical debt, security, compliance, dependencies, migration complexity, expected application lifespan, and potential modernization value.
What Should a Cloud Migration Assessment Cover?
Before applying the 6 Rs, enterprises need a clear understanding of their existing environment.
Application Portfolio
Identify applications, business owners, users, lifecycle status, and business purpose.
Dependencies
Map relationships between applications, databases, APIs, infrastructure, and external services.
Business Criticality
Assess how downtime or migration failure could affect operations and customers.
Security and Compliance
Evaluate access controls, privacy, data residency, cybersecurity, and regulatory requirements.
Cost and Value
Compare current operating costs with migration costs, cloud consumption, licensing, and expected modernization benefits.
A structured assessment also provides the foundation for effective cloud migration consulting and roadmap development.
What Does a Cloud Migration Roadmap Look Like?
After workloads are classified, enterprises can migrate them through controlled waves:
Discover → Assess → Apply the 6 Rs → Prioritize → Design → Migrate → Validate → Optimize
Starting with lower-risk workloads allows teams to validate cloud architecture, security controls, automation, and operational processes before migrating critical systems.
Migration plans should also include data protection, rollback procedures, performance testing, business continuity, monitoring, and post-migration optimization.
What Are Common Cloud Migration Mistakes?
Using One Strategy for Everything
Lift-and-shift may work for some workloads but can transfer technical debt and inefficiencies to the cloud.
Ignoring Dependencies
Migrating an application without understanding connected systems can cause performance and availability problems.
Underestimating Security
Identity, access management, encryption, monitoring, and cloud configuration should be considered from the beginning.
Stopping After Migration
Migration is not the final stage. Cloud environments require ongoing performance, security, reliability, and cost optimization.
Conclusion
The 6 Rs give enterprises a practical framework for determining the right future for each workload.
Rehost and replatform can accelerate migration, repurchase can simplify selected capabilities, and refactoring can unlock greater cloud-native value. Retaining or retiring applications can also prevent unnecessary migration effort.
The objective should not be to move everything to the cloud. It should be to make the right decision for every application based on business value, technology requirements, risk, and long-term modernization goals.
Accelerate cloud transformation with INT.’s assessment, modernization, DevOps, and cloud migration services designed around your enterprise technology landscape. Let’s Connect.
FAQs
1. What are the 6 Rs of cloud migration?
They are Rehost, Replatform, Repurchase, Refactor, Retain, and Retire.
2. What is the difference between rehost and replatform?
Rehosting moves applications with minimal changes, while replatforming introduces selected cloud optimizations.
3. When should an enterprise refactor an application?
Refactoring is suitable when a strategic application requires greater scalability, resilience, maintainability, or cloud-native capabilities.
4. Does every application need to move to the cloud?
No. Some applications may be retained because of technical or regulatory requirements, while obsolete systems can be retired.
5. Why use a cloud migration decision matrix?
It helps enterprises select migration strategies consistently based on business value, technical condition, risk, complexity, and modernization potential.
