The reasons for expediating cloud migration plans can vary, from business continuity to sustain work-at-home employees, the need for greater application uptime and scalability, enhanced disaster recovery, or something else. Regardless of the motivation, to ensure long-term success it’s important to have a distinct approach to cloud migration before diving in. From lift and shift to replatforming or refactoring, there is no single path to success. And, indeed, a hybrid approach is often the ideal answer.
What are the Options?
While there are multiple migration approaches, the three most common are:
Rehost, also known as Lift and Shift, moves applications to the cloud without any code modification. While this approach offers a faster, less resource-intensive migration process, it doesn’t generally benefit from cloud-native features like elasticity. This approach is generally more cost-effective than on-premises computing, but it can be more costly to run applications in the cloud this way versus replatforming or refactoring.
Cloud services ready, or replatforming, migrations move assets to the cloud with a small amount of up-versioning to benefit from cloud infrastructure. Using immutable infrastructure, this approach – while somewhat slower than rehosting – allows workloads to take advantage of base cloud functionality and cost optimization without the necessary resources for refactoring.
Cloud-native migrations, also referred to as refactoring, involve a more advanced process of re-architecting and often re-coding part of an existing application to take advantage of cloud-native frameworks and functionality, like serverless or managed infrastructure. While the most time-consuming and resource-intensive approach, it can offer the lowest monthly spending of the three approaches, as applications are modified to take full advantage of features that maximize operational cost efficiency in the cloud.
Which Migration Path is Best?
Start by examining your IT systems to determine which infrastructure and workloads are of minimal business value and should be retired, and which are of high business value and should move to the cloud. Ask, is the application of strategic benefit to the business? Does it contribute to revenue or is it an application necessary for the business? If the former, it should be invested in, and if the latter, it should be sustained at the lowest possible TCO. This distinction is important, as the resources required for cloud services or cloud-ready migrations are better invested in strategic applications.
Applications with low business value benefit most from infrastructure automation that allows you to reinstall the app in the cloud on new virtual machines (VMs), giving you the opportunity to clear technical debt while adding new best practices like security.
Conversely, applications with high business value require a cost-benefit analysis. Examine the cost for development resources and business interruptions that may occur during a significant rewrite. Carefully compute the business benefits of a cloud-native migration; if the benefits outweigh the cost, and the direction is achievable within the constraints, this is the right approach. Note that due to resource constraints, this approach is usually only taken for a small fraction of applications.
If this approach is not feasible, a cloud-services ready approach is a right choice. Without requiring major code changes, this approach can provide significant cloud benefits like auto-scaling, self-healing, containers, and more. The answers to these questions will illuminate the best path for your cloud migration.
To highlight with an example, an enterprise media company conducted a migration analysis and found that about 50% of its applications should be re-hosted. Ten percent were to be retired or retained on-premises, and the remaining 40% were flagged for replatforming/refactoring given their business-critical nature. Using this strategy, the firm migrated its assets, maximizing cloud benefits for applications that would gain the most while not spending resources on applications that would benefit minimally.
Cloud migration is not a one-size-fits-all exercise. Maximize your cloud computing benefits by mapping your organizational goals and the workloads that support them to those cloud features that will help further those goals. Learn more about conducting a thorough assessment, and building a solid migration plan tailored to your business objectives.
For more information, read the guide; Optimizing IT: Key Considerations for Cloud Migration