Most of the existing applications/projects are being moved to cloud/on-premises platforms using microservices architectures. Assessing the existing application is critical relative to the complexity and risk of the application. An appropriate strategy for analyzing the current application must be defined to determine the risk and complexity of the existing application landscape. The assessment considers factors such as the overall architecture, presentation layer, business layer, data layer, security, implementation, technology, infrastructure, performance, and monitoring of existing applications. Gather the information from the different parameters and decide which is the best option for migration strategies like Rehost, Refactor, Rearchitect and Rebuild. For each parameter, the architect completes the information by studying the existing application/collecting the information from the application stack holders. The application evaluation helps the Organization to understand the following:
- Understanding of existing application architecture and critical findings.
- Integration points between applications (upstream and downstream).
- Infrastructure, Use of software
- Problem areas related to business users.
- Roadmap for the target system platform using any of the migration strategies.
There are a number of evaluation criteria for which information will need to be collected in order to provide an evaluation of applications, as follows:
- Contributions of commercial and technical value such as; Reliability, scalability and flexibility
- Risk exposures such as; Strategic, operational and technological risks
- Cost of operations with respect to the application, the project and the business.
- The attractiveness of the system, the business and the delivery.
Each and every application evaluation team creates a template to prepare and identify the appropriate questionnaire related to the above criteria. Based on the assessment report, the application owner can decide to migrate the application to cloud/on-premises. The following diagram shows a very high-level process flow for evaluating applications.
The following table outlines questions for each of the assessment parameters listed above. The application architect’s score should be based on their experience. For each and every question, the architect has to assign a score and finally decide if the evaluation application can be moved to the target architecture or not. The application architect should answer the following questions before proposing the target architecture in the evaluation phase.
Questions to ask as part of the Migration assessment
The conclusion is that the questionnaire is not limited to the above. Questions can be expanded and values assigned to each question to arrive at a proper assessment of the existing application. Then, according to the report, the application owner can make the appropriate migration decisions. Finally, provide the application migration conclusions and recommendations as part of the migration roadmap document.