FSx for Windows File Server

AWS's fully managed Windows-native shared file storage service, delivering SMB (Server Message Block) file shares backed by Windows Server and integrated directly with Microsoft Active Directory. Where EFS is purpose-built for Linux NFS workloads and FSx for NetApp ONTAP supports NFS, SMB, and iSCSI simultaneously for mixed environments, FSx for Windows File Server is the right choice when your applications, users, or services expect a native Windows file share — one that honours AD user permissions, supports DFS (Distributed File System) namespaces for multi-share aggregation, and exposes Windows ACLs and shadow copies without any translation layer. It deploys in a Multi-AZ configuration with an active standby file server and automatic failover, and integrates with AWS Backup for scheduled, policy-driven backups. Throughput capacity and storage can be scaled independently without downtime, and every file system is encrypted at rest with AWS KMS. DFS namespaces let you group multiple FSx file shares under a single unified path, making it straightforward to migrate on-premises Windows file servers to AWS and keep legacy UNC paths intact. The closest equivalents on other clouds are Azure Files (for SMB workloads on Azure) and OCI File Storage. Use FSx for Windows File Server when you need a fully managed SMB share with native Active Directory integration for Windows-based workloads; use EFS when your workloads are Linux-only and NFS-based; use FSx for NetApp ONTAP when you need multi-protocol access or ONTAP-specific data management features across both Windows and Linux.

A professional services firm migrates its on-premises Windows file server to FSx for Windows File Server. They join the file system to their existing Active Directory domain so existing user permissions carry over unchanged, configure a DFS namespace to preserve the \\corp\shares UNC path that employees already use, and enable Multi-AZ for automatic failover if the primary availability zone becomes unavailable.