Amazon FSx
Fully managed third-party file systems you mount as network shares — Windows, Lustre, NetApp ONTAP, OpenZFS.
Verified against AWS documentation · 2026-09-09
Key facts
- 01Real file systems, not AWS reinventions — AWS runs the servers, patching, and backups; you just mount the share
- 02Four flavors: Windows File Server, Lustre, NetApp ONTAP, OpenZFS. CLF-C02 only expects the first two
- 03Windows File Server: SMB shares, NTFS permissions, joins your Active Directory. Single-AZ or Multi-AZ, SSD or HDD, up to 64 TB per file system
- 04Lustre: sub-millisecond latency for HPC/ML, and can link to an S3 bucket so objects appear as files. Scratch = temporary and cheap, persistent = replicated and backupable
Exam triggers
Phrases and scenarios that point here.
- "Windows applications", "SMB", "Active Directory", "NTFS permissions" → FSx for Windows File Server
- "High performance computing", "machine learning training", "genomics", "seismic", "rendering" → FSx for Lustre
- Move an on-prem Windows file share to AWS without rewriting the app → FSx, not EFS
- Compute needs to chew through a dataset already sitting in S3 at full speed → FSx for Lustre linked to the bucket
Not this service
- Linux/NFS shared file storage → EFS
- A disk attached to one EC2 instance → EBS
- Data reached over an API instead of a file path → S3
Use cases
- 01Retiring the on-prem Windows file server finance and HR live on — same mapped drive, same AD logins, nobody files a ticket
- 02Home directories and department shares for a fleet of WorkSpaces desktops
- 03ML training where expensive GPU instances would otherwise sit idle waiting on S3 — Lustre stages the dataset and feeds them at line rate
- 04Batch science runs (genomics, CFD, seismic): create a scratch Lustre file system for the job, export results to S3, delete the file system
- 05Render farms and video post-production where dozens of nodes read and write the same project files at once
How it's charged
- 01Provisioned, not consumed — you pay hourly for the capacity you configure, whether the share is busy or empty
- 02FSx for Windows meters four things: storage (GB-month), throughput capacity (MBps-month), SSD IOPS above the 3 per GB included free, and backup storage
- 03Deployment choices move the bill more than usage does: Multi-AZ costs more than Single-AZ, SSD more than HDD
- 04Lustre scratch is the cheap tier — no replication, no backups; persistent replicates and can be backed up, and costs more
- 05Multi-AZ replication traffic is bundled into the throughput price, but clients reaching the file system across AZs or Regions pay normal data transfer
