As shown in FIGURE 13-1, the common components of a cloud migration include the following:
Applications
Data
Infrastructure
Moving an application from the cloud involves rehosting the application from an on-premise server to a server in the cloud. Such applications may be custom solutions that currently run on the web to enterprise solutions, such as the migration from an on-premise Exchange server to Microsoft 365. An infrastructure migration, in contrast, might include moving an Active Directory domain server to the Microsoft Azure Cloud. Finally, a data migration might be as simple as directing users to leverage cloud-based disk storage, such as OneDrive or moving to an on-premise database to a cloud-based database server or database-as-a-service (DBaaS) solution.
When you plan for a cloud migration, you do not have to move all three components at the same time. Instead, you may find the migration process more manageable and less disruptive if you approach it one component at a time, meaning, you first move infrastructure solutions, followed by data, and finally your applications. You may base the prioritization of which component you move first based on the following:
Business risks
Costs
Number of underlying components
Security
Available personnel resources