The journey to the cloud is different for every organization as there is no one-size-fits-all migration plan. Each IT asset to be migrated is unique in terms of cost, performance, and complexity, so you cannot move all components to the cloud with one common method. Making a roadmap for the migration will answer the questions of what, how, and in what order to move each system . This is where the cloud migration strategies come into play.
When planning to migrate on-premises infrastructure to the public cloud, there are 6 strategies that can be adopted to help ensure a smooth and successful transition.
It is important to analyze application portfolios and categorize them against the 6 R’s. We can use AppWorks as an example:
- Rehosting: Also known as “Lift and Shift”, this strategy lifts servers and applications from the on-premises infrastructure and shifts them to a cloud infrastructure. Many organizations adopt this strategy as it carries the least amount of risk. Rehosting is favored for its relative ease, speed and low risk compared to other migration strategies. For example, an OT product like AppWorks platform will have a dependency on Host Name.
- Replatforming: Also known as “Lift, Shift and Tweak”, this strategy is a small variation from rehosting. The core architecture of the application remains the same, but a small portion of the application is adapted to leverage new cloud features. AppWorks platform and its applications use a backend database server, so one could consider using the Managed Instance Database Service.
- Repurchasing: This strategy is also called “Drop and Shop”. An organization can eliminate significant migration efforts by moving the on-premises application with a cloud-native vendor-packaged software. It typically means moving to a SaaS (Software as a Service) application with the same capabilities. Usually, it entails a licensing change where the existing on-premises license is dropped and a new license agreement is started with the cloud provider for their solution. The newer, upgraded cloud version offers better value with higher efficiency, savings on app storage, and maintenance costs.
- Refactoring: Also known as “Re-architecting”, method involves rewriting applications from scratch to make them cloud native. Refactoring is much more complicated than other cloud migration approaches because it requires application code changes and must be tested to avoid regressions in functionality. For example, this would apply when the developed application on AppWorks platform is refactored from an on-premises monolithic architecture to a fully serverless architecture in the cloud.
- Retiring: In the ‘retire’ strategy, applications that are no longer needed for IT portfolios are removed. If an application is considered not worth migrating to the cloud, it can be eliminated/downsized. It allows for all applications to be considered in terms of their use, dependencies, and cost to the company
- Retaining: Despite all the benefits of cloud technology, there are still reasons to retain some applications on-premises. For example, an application database is critical for the business and an organization may like to keep this on-premises rather than migrating it to the cloud. Retaining is often used in hybrid cloud deployment to ensure business continuity during large-scale migrations. It offers benefits of the cloud as well as keeping critical workloads and confidential data on-premises.
Choose the right cloud computing model
The other decision to be made is what type of cloud computing model is right for the Cloud migration – IaaS, PaaS, or SaaS?
- Infrastructure as a Service (IaaS) – This computing model provides the infrastructure needed to run applications. Assets such as software and hardware, storage and networking are made available. This model is best suited when planning to rehost or re-platform applications.
- Platform as a Service (PaaS) – This computing model provides the Infrastructure as a Service and a set of deployment tools, software development, and middleware that enable fast migration. Organizations looking to refactor or rebuild applications can look at this option.
- Software as a Service (SaaS) – Organizations looking to replace their applications with off-the-shelf alternatives can choose SaaS services. The SaaS vendor takes care of both infrastructure and the application that the organization uses.
Many factors contribute to an organization’s decision on which cloud adoption strategy and computing model works for their organization. We would recommend firstly to analyze the current footprint and understand which applications to retain, which to retire, and which ones to consider for cloud migration. For each application, determine the appropriate cloud migration path, keeping in mind the effort involved and the costs that need to be incurred. Further, estimate the time required for the migration.
OpenText™ Professional Services has vast experience in helping customers to migrate their OpenText Products hosted on on-premises (off-Cloud) to Cloud. Contact us to discuss your requirements for your migration project.
Author – Madhusudan Reddy is a Principal Architect in OpenText Professional Services India working on multiple OpenText technologies to serve global customers with best practice solutions for AppWorks Platform.