Understanding the 7 R's of Cloud Migration

author Adam Hamšík
CEO & Co-Founder

The key is to find the right strategy aligning with an organization’s specific needs and future goals.

Cloud migration is not a one-size-fits-all process. Different strategies cater to different needs, and understanding these can be crucial for a successful transition. Over the years of our experience with migrating infrastructures to AWS we’ve came across the seven R’s of cloud migration:

  1. Retire: This strategy involves decommissioning or archiving applications that no longer provide business value or are costly to maintain. By retiring applications, you can reduce costs, security risks, and the complexity of your IT landscape.
  2. Retain: Some applications might be better off staying in their current environment due to reasons like compliance, high migration risks, unresolved dependencies, or recent upgrades. Retaining can be a temporary measure, with migration considered in the future.
  3. Rehost (Lift and Shift): This strategy involves moving applications to the AWS Cloud without any modifications. It’s a direct transfer, ensuring minimal disruption and downtime. However, it might not fully leverage cloud-native features, leading to inefficiencies.
  4. Relocate: This strategy allows for the bulk transfer of servers from on-premises platforms to their cloud equivalents. It’s a quick migration method that doesn’t alter the application’s architecture, ensuring minimal disruption.
  5. Repurchase (Drop and Shop): Here, you replace your current application with a different version or product, often moving from a traditional license to a Software as a Service (SaaS) model. This can lead to reduced costs and infrastructure maintenance.
  6. Replatform (Lift, Tinker, and Shift): This involves moving the application to the cloud with some level of optimization. It’s a middle ground between rehosting and refactoring, allowing for cloud benefits without a complete overhaul.
  7. Refactor (Re-architect): This is the most involved strategy, where applications are re-architected to fully utilize cloud-native features. It’s driven by the need for scalability, agility, and performance improvements.

Selecting the right migration strategy is crucial. While rehosting, relocating, and replatforming are commonly chosen for large migrations due to their simplicity, refactoring is often avoided in such scenarios because of its complexity. However, post-migration, refactoring can be considered to modernize the application further.

Rehost [Lift & Shift]

Definition: Rehosting, commonly known as the “lift and shift” approach, involves moving applications directly from an on-premises environment to the cloud without any modifications.


  1. Speed: One of the quickest ways to migrate to the cloud.
  2. Minimal Disruption: Since there’s no change to the application, there’s minimal business disruption.
  3. Compatibility: Direct transfer ensures that applications remain compatible with existing systems and processes.


  1. Cost Implications: Simply lifting and shifting can lead to underutilized cloud resources. Without optimization for the cloud environment, you might end up paying for resources you don’t need.
  2. Technical Debt: This approach can accumulate significant technical debt. By merely transferring an application without optimizing it for the cloud, you’re setting yourself up for future challenges. This can lead to a situation where you’re operating in both cloud and on-premises environments, increasing complexity and costs.
  3. Missed Opportunities: Rehosting doesn’t leverage cloud-native features, meaning you miss out on the scalability, resilience, and agility that cloud platforms offer.


Definition: Relocating involves transferring a large number of servers, possibly encompassing multiple applications, from an on-premises platform to a cloud version of the same platform. It’s akin to moving from one room to another, where the layout remains the same.


  1. Quick Migration: Like rehosting, relocating is a fast way to get your applications into the cloud.
  2. Consistency: Since you’re moving to a cloud version of your current platform, there’s a level of familiarity and consistency.
  3. Minimal Disruption: The application continues to serve users during the migration, ensuring business continuity.


  1. Cost Concerns: Relocating without optimizing for the cloud can lead to inflated costs. You might be paying for resources or services that aren’t fully utilized.
  2. Technical Debt: Similar to rehosting, relocating can lead to technical debt. Over time, this can become a burden, especially if there’s a need to integrate with other cloud-native services or scale the application.
  3. Operational Burnout: Managing applications that are merely relocated can be taxing. The operational team might find themselves juggling between the nuances of on-premises operations and the intricacies of cloud management, leading to burnout.


While both Rehosting and Relocating offer quick migration paths, they come with their own set of challenges. The allure of a swift transition can be overshadowed by the long-term implications of high costs, technical debt, and operational challenges. It’s essential to weigh these factors and consider future-proofing your applications by leveraging cloud-native features and optimizations.

Fig. 1 Cost of Lift and Shift Over Time (Cloud Migration)

Replatform [Lift, Tinker, and Shift]

Definition: Replatforming involves moving the application to the cloud with some level of optimization. It’s about making a few adjustments to the application to benefit from the cloud environment without changing its core architecture.


  1. Optimized Costs: By making minor adjustments, you can ensure that the application uses cloud resources more efficiently, potentially leading to cost savings.
  2. Leverage Cloud Features: Even with minor changes, you can start taking advantage of some cloud-native features, enhancing performance and scalability.
  3. Reduced Technical Debt: By optimizing applications during the migration, you reduce the chances of accumulating technical debt in the future.
  4. Flexibility: Replatforming offers a balance between speed and optimization, allowing businesses to start benefiting from the cloud without a complete overhaul.


  1. Intermediate Complexity: While not as complex as refactoring, replatforming does require some changes, which can introduce risks if not managed properly.
  2. Potential for Future Changes: As the application evolves, there might be a need for further optimizations or changes down the line.

Key Considerations and Speed-ups:

  • Kubernetes and Containerization: Many modern applications are already containerized. Migrating to a cloud-native Kubernetes solution can significantly speed up the replatforming process. Managed Kubernetes solutions, like AWS EKS or Google Kubernetes Engine, can seamlessly integrate with these containerized applications, making the transition smoother.
  • Operational Simplicity: Adopting managed Kubernetes solutions can reduce overall operational complexity. With a more streamlined and automated environment, there are fewer page calls and manual interventions, leading to more straightforward operations and reduced chances of human-induced errors.

Experience Matters: The replatforming journey can be complex, but having an experienced migration partner can make a world of difference. Engaging with a partner who has a track record of successful cloud migrations, and helped customers replatform their applications can provide valuable insights, best practices, and accelerate the whole process.

Fig. 2 Replatform as a Required Step to Optimized Cloud Costs


Replatforming offers a balanced approach to cloud migration. By leveraging containerization and managed Kubernetes solutions, businesses can achieve a faster and more efficient migration. The reduced operational complexity not only simplifies management but also cuts down on potential issues. However, the journey’s success often hinges on experience. Partnering with seasoned experts can provide the guidance and expertise needed to navigate the complexities of replatforming effectively. Only by doing required steps(replatforming of existing workload is one of them) users can reap all benefits of cloud and get to optimized cloud bill. 

Refactoring [Embracing Cloud-Native Capabilities]

Refactoring, often referred to as re-architecting, is a migration strategy that involves a deep transformation of the application to fully harness the capabilities of the cloud. It’s not just about moving to the cloud; it’s about evolving and optimizing the application to become cloud-native.


  1. Maximized Cloud Benefits: Refactoring allows applications to fully leverage cloud-native services, tools, and features, ensuring optimal performance, scalability, and resilience.
  2. Cost Efficiency: While there’s an initial investment, a refactored application can lead to long-term cost savings due to optimized resource usage and reduced maintenance overhead.
  3. Future-Proofing: By adopting modern development practices and technologies, refactored applications are better positioned to adapt to future business needs and technological advancements.
  4. Enhanced User Experience: With improved performance and scalability, users often benefit from faster response times and more reliable services.
  5. Security Improvements: Refactoring can also involve integrating advanced cloud-native security features, enhancing the application’s overall security posture.


  1. Initial Complexity: Refactoring is a comprehensive process that can be complex and resource-intensive.
  2. Dual Maintenance: Teams have to juggle maintaining the existing application while developing the refactored version, potentially stretching resources thin.
  3. Transition Risks: Post-refactoring, there are risks associated with transitioning to the new system, including potential disruptions, data inconsistencies, or loss.
  4. Time-Consuming: Compared to other migration strategies, refactoring can be more time-consuming due to the depth of changes involved.


Refactoring is a commitment to fully optimizing an application for the cloud environment. It demands significant effort, expertise, and resources, but the long-term benefits in terms of performance, scalability, and cost savings can be substantial. The journey, while intricate, can redefine how an organization operates and delivers value, making it a strategic consideration for those looking to fully embrace the cloud paradigm.

Conclusion [Overall]

The seven R’s of cloud migration – Retire, Retain, Rehost, Relocate, Repurchase, Replatform, and Refactor – outline the diverse pathways for businesses transitioning to the cloud. Each offers distinct advantages and challenges. While Rehosting and Relocating provide quick migration solutions, they can bring long-term inefficiencies. On the other hand, Refactoring, although resource-intensive, ensures optimal cloud utilization.

The key is to find the right strategy aligning with an organization’s specific needs and future goals. In our next blog, we’ll focus on the Rehosting approach, also known as “Lift & Shift,” exploring its intricacies and real-world implications.

AWS cloud migration

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