There are two methods to migrate applications to AWS. They are as follows:
This method is typically used for tightly coupled application or self contained applications. It is a one time migration. The advantages gained is shrinking of existing IT infrastructure footprint and having focus on rapidly building features to cater to changing business needs.
In this method, a portion of the application / data is migrated to cloud while the remaining part is on-prem thus creating a hybrid environment. This is ideal for large systems with many electronic data interfaces. This is typically a low risk approach and parts can be moved over a period of time.
In this option, we move the application from physical machines which are on-prem to cloud without disconnecting the application. Storage, memory and connectivity is replicated from physical machines to cloud.
In this option, we clone the Operating System image and it is typically a one-time migration.
We move the data from the on-prem storage systems to cloud. We develop a data selection strategy and push the data to cloud.
This option is selected for migrating distributed applications and we use OS level virtualization method.