
The “7 Rs” of Cloud Migration
The competition is fierce out there, folks, and the cloud is only raising the stakes. According to the CDW Cloud Computing Research Report, 45% of organizations have already migrated half of their applications to the cloud. That means that more companies than ever are enjoying benefits such as reduced operational costs, easy data access, and more scalable resources.
If you want to keep up, it’s time to start planning your cloud migration.
But let’s be clear: a cloud migration is no walk in the park. It’s a complex, multifaceted process that demands careful planning, sharp attention to detail, and a solid strategy.
Enter the “7 Rs” of cloud migration. These strategies – rehost, relocate, replatform, refactor, repurchase, retire, and retain – provide a structured approach to moving your applications and data to the cloud, each with its own purpose and advantages.
In this article, we’ll explain exactly how each strategy works, when to use them, and share real-world examples along the way. Let’s dive in!
Why Is a Strategy Important?
You’ve got a solid plan, done your homework, and carved out enough time for your migration – so you should be good to go, right? Not quite. While those are essential steps, you’ll still need a clear strategy for each migration point (every individual item you plan on moving to the cloud). Without these individual strategies, the entire migration process can spiral into chaos. Put simply, you’ll be flying by the seat of your pants.
When Should You Implement a Strategy?
Once you’ve assessed and prioritized your applications, but before the migration itself begins, it’s time to map out what strategies you’ll be using. Each strategy is tailored to specific applications and workloads, meaning you’ll likely use several different strategies throughout the migration process.
Think of these strategies as detailed instruction manuals for your applications. Each one provides clear, step-by-step guidance so everything gets uploaded to the cloud smoothly and efficiently.
As always, you should work with an IT expert throughout this process. Expert guidance is vital for an IT project as large and complicated as a cloud migration.
A Brief Overview of the R Models
Gartner coined the “5 Rs migration strategy” back in 2010 to provide a framework that organizations could use to migrate their applications to the cloud. Since then, Amazon Web Services (AWS) has expanded on this framework by adding the two extra “Rs,” Retire and Retain, as a reaction to the increasing complexities of cloud migration.
But what exactly are the “7 Rs”?
1. Rehost (Lift and Shift)
Rehosting is when you simply drop an application from a physical device into the cloud and hope for the best. For many apps, this is a fast and easy way to get your data on the cloud.
When to use it: Use rehosting when you need to migrate an application to the cloud quickly due to resource or time constraints.
Example: Moving your company’s email system directly to Microsoft Office 365 without making any changes.
Pros
- Easy to do with no coding changes required.
- Minimizes disruptions to business operations.
- Avoids costly upgrades, saving money in the short-term.
Cons
- Applications may not perform well in the cloud without optimization and testing.
- There’s a risk that the migrated application won’t be able to access its old data due to its new location.
2. Refactor (Re-Architect)
Refactoring is the most complex migration strategy. It involves reworking and restructuring an application to fully take advantage of its new cloud-based home. This process usually requires significant coding changes resulting in an application that can make the most of its new life in the cloud.
When to use it: Use refactoring when an application needs to take full advantage of its new cloud features and would suffer without the enhancements.
Example: Updating an old scheduling app so it works faster, syncs with mobile devices, and handles more data in the cloud.
Pros
- Gives your team the flexibility to retool the application as needed.
- Employees can use the application as they always have, with little to no noticeable changes.
- Helps avoid long-term compatibility issues, potentially saving money down the road.
Cons
- It’s an expensive and time-consuming process.
- The application may be unavailable for a longer period during migration.
- Carries a higher risk of migration failure compared to other strategies.
3. Replatform (Lift, Tinker, and Shift)
A middle ground between rehost and refactor, replatforming involves moving an application to the cloud with minor adjustments to help it perform better in its new home. While these changes aren’t as extensive as refactoring, they can help an application take advantage of key cloud features without the complexity of a complete overhaul.
When to use it: Choose replatforming when you want to boost an application’s cloud performance without committing to a major redesign.
Example: Tweaking an online store so it can automatically handle more shoppers during peak sales without crashing or slowing down.
Pros
- Small-scale changes reduce risk and avoid overcommitment to a large-scale project.
- Helps your applications to better use cloud features, like scalability.
- More affordable than refactoring.
Cons
- Without proper planning, the project could end up growing into a full-scale refactoring effort.
- Best suited for basic cloud adjustments and isn’t as customizable as refactoring.
- May introduce compatibility issues if not thoroughly tested.
4. Relocate (Hypervisor-Level Lift and Shift)
The relocate strategy is used when moving existing virtual machines to the cloud. Similar to rehosting, this approach targets virtualized servers and involves transferring them to a cloud-based environment while keeping their configurations intact.
When to use it: Relocating is great for when you need to move virtual machines to the cloud without changing their existing setups.
Example: Moving your business’s existing virtual machines from an on-premises server to the cloud.
Pros
- Minimizes downtime and disruptions during the migration.
- Keeps applications and configurations unchanged.
Cons
- Compatibility issues may occur with the new cloud provider.
- Some adjustment may be necessary to work best with cloud features.
5. Repurchase (Drop and Shop)
Sometimes, an application needs to be replaced by its improved cloud-based version. This will require you to repurchase the applications as software-as-a-service (SaaS) solution. The cloud-based version typically keeps the core functions you’re used to, but it’s optimized for the cloud, offering additional features and benefits.
When to use it: This strategy works best when your current software is outdated or no longer meets your needs.
Example: Replacing your old, on-premises accounting software, like QuickBooks Desktop, with its cloud-based counterpart, QuickBooks Online.
Pros
- Fast to deploy since you’re starting with an existing, ready-to-use solution.
- Cloud-based applications are designed to take full advantage of the cloud.
- Easier to maintain than older, on-premises software.
Cons
- Cloud-based software can come with high upfront fees or subscription costs.
- Your team will need to learn how to use the new software.
- Migrating old data into the new software may be challenging.
6. Retire (Stop Using)
Some applications simply aren’t suited for the cloud. This might be because the app is no longer supported, or the effort to get the app to work in the cloud isn’t worth it. In the end, the result is the same: you stop using the application.
When to use it: Retire an application when it no longer fits into your plans or would cause too many issues during migration.
Example: Removing an old employee time-tracking system that no longer works with modern tools.
Pros
- Easy to implement since you’re not migrating the app.
- Saves time by eliminating obsolete software.
- Frees up resources by removing underperforming applications.
Cons
- Retiring an app too early can cause issues for those still relying on it.
- Without a suitable replacement, you may find holes in your systems.
7. Retain (Revisit Later)
This strategy is for applications that can’t be retired yet – either because they depend on another system that needs to be moved first, or because there’s no immediate benefit to migrating them. Instead of migrating right away, you decide to revisit the application at a later time.
When to use it: This approach is best for organizations looking to make the most of their resources or those considering a hybrid cloud migration. It’s also useful when an application requires local data for compliance or security reasons.
Example: Keeping an internal reporting tool in its current setup until other, more critical systems have been moved to the cloud.
Pros
- Delays migration until it’s more beneficial or feasible.
- Saves resources during your migration by prioritizing more important applications.
Cons
- Old software can become costly to maintain.
- Retained applications will remain outside of the cloud, which can become cumbersome.
- Delaying migration may lead to unforeseen issues down the line.
Need a Strategy Guide?
If all of this seems confusing and complex, that’s because it is. But don’t worry – you don’t have to navigate your migration alone. We’re here to help.