Cloud migration strategies: understanding the 7 Rs

Moving to the cloud is no longer a question of “if” for most businesses, but “when and how”. Cloud migration brings flexibility, scalability, and cost benefits — making it an essential part of modern digital infrastructure. However, successful cloud migration strategy requires planning, and that’s where understanding the “7 Rs” plays a pivotal role. 

This strategy is a set of approaches designed to help organisations plan and execute their migration to the cloud. The model was originally introduced by Gartner in the early days of cloud computing, and has now evolved to include an additional 2 Rs as cloud computing has evolved.

What are the 7 Rs of cloud migration strategy?

The “7 Rs” represent the key strategies businesses use to transition workloads to the cloud. Each approach addresses different types of workloads, organisational needs, and objectives. Here’s a closer look at each method:

1. Rehost (Lift and Shift)

Rehosting is the simplest migration method. It involves moving your existing applications and data to the cloud without significant changes. Many businesses use this strategy when they need to migrate quickly or lack the resources to reconfigure their applications. Rehosting can act as a first step, allowing organisations to modernise applications once they’re already in the cloud environment.

Advantages of Rehosting

• Speed: Offers the quickest possible cloud migration.
• Simplicity: Makes the migration procedure less complicated.
• Cost-effective: Reduces initial expenses by steering clear of significant redesigns.

Limitations of Rehosting

• Limited optimisation: Doesn’t fully utilise cloud-native capabilities that could save costs and increase performance.
• Technical debt: Could introduce inefficiencies and legacy problems into the cloud environment.
  

2. Relocate (Hypervisor-Level Lift and Shift)

Relocation is similar to Rehosting but operates at the hypervisor level. This strategy involves moving entire virtual machines to cloud infrastructure without making any changes to applications. Relocationingis particularly beneficial for businesses using VMware or similar environments looking for a quick transition without disruption to services.

Advantages of Relocation

• No application changes required: Since the entire virtual machine environment is migrated as-is, there’s no need to modify or refactor applications, saving time and resources.
• Familiarity and compatibility: Organisations using platforms like VMware can maintain their existing tooling and configurations, making the migration process easier for IT teams.
• Reduced disruption: The strategy minimises disruptions to operations, ensuring that applications run on the cloud almost exactly as they did on-premises.

Limitations of Relocation

• Cost inefficiency: Applications moved without modification may not fully utilise cloud-native capabilities, potentially leading to higher operational costs.
• Performance concerns: Workloads optimised for on-premises infrastructure may not perform as efficiently in the cloud, especially if they’re not adapted to cloud-specific architecture.
• Limited scalability: The approach does not inherently take advantage of the cloud’s elastic scaling capabilities, potentially restricting growth.

3. Replatform (Lift and Reshape)

Replatform cloud migration is about making minor adjustments to your applications while migrating to cloud. These tweaks are usually made to take advantage of cloud capabilities, like scaling options or managed services. For instance, businesses might update their database layer to a cloud-native service during the transition without restructuring the entire application.

Advantages of Replatforming

• Increased productivity: Adapts apps to take use of cloud-native capabilities like managed services and scalability.
• Savings: By employing cloud infrastructure more skillfully than merely Rehosting, it is possible to lower operating costs.
• Less risky: Because the basic application design is unaltered, it is less dangerous than complete rearchitecting.

Limitations of Replatforming

• Limited transformation: Despite the advancements, not all cloud-native features may be completely utilised.
• Possible modifications: To integrate into the cloud environment, some components of the application might need to be modified.

4. Refactor (Re-architect)

Refactoring involves significant modifications or rebuilding applications to be cloud native. This strategy focuses on leveraging cloud-native features such as microservices architecture, serverless computing, or containerisation to maximise performance. While it tends to require more upfront investment, Refactoring delivers exceptional scalability, agility, and long-term savings.

Advantages of Rearchitecting

• Full optimisation:Enhances performance, scalability, and resilience by making the most of cloud-native capabilities.
• Long-term savings:Even though it may be expensive at first, it may result in increased productivity and lower expenses.
• Innovation enablement:Contemporary development techniques and technologies, such as serverless computing and microservices can be adopted.

Limitations of Rearchitecting

• High initial cost:Requires a large time, resource, and skill commitment.
• Complexity: Involves intricate restructuring that can lead to challenges during the transition.
• Business disruption:It may affect on how businesses operate while the migration is underway.

5. Repurchase (Drop and Shop)

Repurchasing refers to replacing an existing application with a new, cloud-based solution. Typically, businesses opt for software-as-a-service (SaaS) platforms that better meet their needs. For example, migrating from an on-premises CRM to cloud platforms such as Salesforce. This strategy is useful when the existing application no longer aligns with the business’ needs or when upgrading is more cost-effective.

Advantages of Repurchasing

• Streamlining: Simplifies IT portfolios by lowering the quantity of apps that require management.
• Innovation access: Gives users access to the newest features and advancements that SaaS platforms often provide.
• Less maintenance: Responsibility is shifted to the SaaS provider for the duty of updating and maintaining the applications.

Limitations of Repurchasing

• Costs for subscriptions: Because of subscription arrangements, this may incur continuous operating expenses.
• Integration difficulties: Data migration and integration with current systems may be necessary.
• Feature parity: There’s a chance the new product won’t have every feature of the current one.

6. Retire (“Get Rid of”)

During the cloud migration process, companies often identify workloads or applications that aren’t adding value. Retiring these outdated resources not only reduces costs but simplifies the migration effort. A thorough review of your IT portfolio can reveal which applications are no longer necessary and can be decommissioned instead of migrating.

Advantages of Retiring

• Cost reduction:Removes the need to maintain and run antiquated systems.
• Simplification:Reduces the complexity of the migration’s scope and the IT environment.
• Focus on value: Enables businesses to concentrate on enhancing and moving systems that offer genuine business value.

Limitations of Retiring

• Discovery challenges:Determining which systems should be decommissioned and reaching a consensus on them can be challenging.
• Business alignment: To guarantee that no crucial activities are interrupted, alignment with business units is necessary.

7. Retain (“Revisit”)

Sometimes, the best decision is not to migrate a workload at all. If certain data or applications still offer value while operating in their current environment, retaining them as-is until a later migration phase might be the wisest choice. For example, legacy workloads with no immediate cloud benefits or that have strict compliance restrictions may remain on-premises.

Advantages of Retaining

• Compliance:Guarantees that legal and compliance requirements are properly followed.
• Stability:Maintains the stability of change-sensitive applications.
• Cost management:Prevents needless migration expenses for systems that are not advantageous to migrate or cloud-ready.

Limitations of Retaining

• Missed opportunities:Retained apps may not be able to make use of cloud services.
• Management complexity:Preserves the intricacy of managing a distinct environment in addition to cloud infrastructure.

When should you use each migration model?

Understanding when to apply each strategy is vital to making informed decisions. Here’s a simplified table to help you choose the right model based on workload, urgency, and organisational goals:

How OneAdvanced can help?

OneAdvanced’s relationship with Microsoft goes back over 30 years, over which our Azure experts have helped numerous organisations leverage the benefits of the cloud. We advise, assist, secure, and operate – wherever you may be on you cloud journey. 

Get in touch with our team today to see how we can help.