Ask yourself why do you need cloud migration

Before looking to cloud migration various factors need to be verified. Few of the are

1. What is the business gain/value for the migration ?
2. What is the organization goals in terms of cloud migration ?
3. Rough estimation of migration cost vs business value
4. What is the status of product life cycle ? Is it in sunset mode ?
5. What are the COTS products used ?
6. What is the license cost changes after migration if any ?
7. Will you able to provide atleast AS-IS functional and non functional requirements of the application.
8. What is the cloud migration strategy that benefit the clients, application and organization ?
9. How to validate AS-IS functionality after migration. How many types of test cases are there ? Is there any need to create new test cases ? (Devils are in details)
10. What is the level of data confidentiality ?
11. What are the readily available cloud features help to reduce the cost of application ?
12. Is user authn and authz are same after migration ? How to migrate users to new platform ?
13. What is the disaster recovery plan ?

Below are the cloud migration strategies:

Cloud migration involves moving applications, data, and other business elements from an organization's on-premises infrastructure to a cloud computing environment. There are several types of cloud migration strategies, each with its own advantages and challenges. Here are some common types of cloud migration:

1. Rehosting (Lift and Shift):

   • Description: In rehosting, also known as "lift and shift," the goal is to quickly migrate applications and data to the cloud without making significant changes to their architecture.
   • Advantages: It is a relatively fast and straightforward approach. It requires minimal modification to existing applications.
   • Challenges: May not fully leverage cloud-native features, potentially missing out on cost savings and performance improvements.

2. Replatforming (Lift, Tinker, and Shift):

   • Description: Replatforming involves making some optimizations to the existing applications for better performance and cost efficiency while still maintaining the core architecture.
   • Advantages: Provides an opportunity to take advantage of some cloud-native features without a complete redesign.
   • Challenges: Requires more effort than rehosting and may not fully harness the benefits of cloud-native technologies.

3. Refactoring (Re-architecting):

   • Description: Refactoring, or re-architecting, involves making significant changes to the existing application architecture to fully leverage cloud-native services and features.
   • Advantages: Maximizes the benefits of the cloud, including scalability, elasticity, and cost efficiency.
   • Challenges: Requires more time and resources compared to rehosting or replatforming. It involves redesigning parts of the application.

4. Rearchitecting for Containers:

   • Description: Containers provide a lightweight, portable, and scalable way to package and deploy applications. Rearchitecting for containers involves containerizing applications for better consistency across different environments.
   • Advantages: Enables consistent deployment and scaling of applications. Improves resource utilization and facilitates easier management.
   • Challenges: Requires changes to the application architecture to work effectively with containers.

5. Rebuilding (Full Rewrite):

   • Description: Rebuilding involves rewriting the entire application from scratch to take full advantage of cloud-native services and architectures.
   • Advantages: Offers the maximum benefits of cloud computing, including scalability, agility, and cost efficiency.
   • Challenges: Requires significant time, resources, and expertise. Often chosen for legacy applications that need a complete overhaul.

6. Hybrid Cloud Migration:

   • Description: In a hybrid cloud migration, organizations maintain some applications and data on-premises while migrating others to the cloud. This allows for a gradual transition and flexibility.
   • Advantages: Provides a balance between on-premises and cloud resources. Allows organizations to retain sensitive data on-premises while leveraging cloud benefits for other workloads.
   • Challenges: Requires careful planning and integration between on-premises and cloud environments.

The choice of migration strategy depends on factors such as the specific goals of the organization, the nature of the applications, and the available resources. Organizations often adopt a combination of these strategies based on their unique requirements.