A financial services company wants to shut down two data centers and migrate more than 100 TB of data to AWS. The data has an intricate directory structure with millions of small files stored in deep hierarchies of subfolders. Most of the data is unstructured, and the company’s file storage consists of SMB-based storage types from multiple vendors. The company does not want to change its applications to access the data after migration. What should a solutions architect do to meet these requirements with the LEAST operational overhead?

The correct answer is to use AWS DataSync to migrate the data to Amazon FSx for Windows File Server. DataSync is ideal for large-scale migrations of file data, especially with millions of small files and complex directory structures, as it automates and accelerates the transfer. FSx for Windows File Server provides fully managed, highly reliable, and scalable file storage accessible via the SMB protocol, which directly supports the company's existing SMB-based applications without modification, minimizing operational overhead. Using AWS Direct Connect to migrate to Amazon S3 would require application changes to access object storage, which is not allowed. Using AWS DataSync to migrate to Amazon FSx for Lustre is incorrect because Lustre is a high-performance file system typically used for HPC workloads and does not natively support SMB, again requiring application changes. Using AWS Direct Connect to migrate to an AWS Storage Gateway volume gateway would involve setting up and managing a gateway, which adds more operational overhead than a direct DataSync migration to a fully managed FSx service.