FSx Storage Options: Lustre for HPC, Windows for SMB, and ONTAP for Enterprise NAS

Four FSx flavors, four use cases

Amazon FSx is not one service — it's four managed file systems with different underlying technology, protocols, and performance characteristics:

| FSx Type | Protocol | Best for | Peak throughput | |---|---|---|---| | FSx for Lustre | POSIX (Lustre client) | HPC, ML training, parallel I/O | Hundreds of GB/s | | FSx for Windows File Server | SMB, NTFS | Windows apps, AD integration | Tens of GB/s | | FSx for NetApp ONTAP | NFS, SMB, iSCSI | Enterprise NAS, multi-protocol | Tens of GB/s | | FSx for OpenZFS | NFS | Linux workloads needing ZFS | Tens of GB/s |

EFS (NFS, POSIX, Linux) is often the right answer before reaching for FSx. FSx is for when EFS's performance or protocol support isn't sufficient.

FSx for Lustre: ML training pattern

The standard pattern for ML training on AWS: data in S3, FSx for Lustre as the high-speed training scratch space, EC2/SageMaker GPU instances mount via Lustre client.

# Create a persistent FSx Lustre file system linked to S3
aws fsx create-file-system \
  --file-system-type LUSTRE \
  --storage-capacity 1200 \
  --subnet-ids subnet-12345678 \
  --lustre-configuration '{
    "DeploymentType": "PERSISTENT_2",
    "PerUnitStorageThroughput": 250,
    "DataCompressionType": "LZ4",
    "ImportPath": "s3://my-training-data/datasets/",
    "ExportPath": "s3://my-training-data/results/",
    "AutoImportPolicy": "NEW_CHANGED_DELETED"
  }'

# Mount on EC2 instance (requires lustre-client kernel module)
sudo amazon-linux-extras install -y lustre
sudo mount -t lustre \
  -o relatime,flock \
  fs-12345678.fsx.us-east-1.amazonaws.com@tcp:/abcdef \
  /fsx

PerUnitStorageThroughput: 250 means 250 MB/s per TB of storage. A 4.8TB file system provides ~1.2 GB/s throughput. For deep learning training, this keeps GPUs fed without I/O bottlenecking.

AutoImportPolicy: NEW_CHANGED_DELETED keeps the FSx file system synchronized with S3 as objects are added or removed — new training data added to S3 becomes visible in the mount point without manual re-import.

FSx for Windows File Server: SMB and Active Directory

FSx for Windows File Server provides a native Windows file system with full NTFS, SMB 2.x/3.x, and Active Directory integration. It's the migration path for Windows file servers that need to move to AWS.

resource "aws_fsx_windows_file_system" "main" {
  active_directory_id = aws_directory_service_directory.corp.id
  storage_capacity    = 300  # GB
  subnet_ids          = [aws_subnet.private_az1.id, aws_subnet.private_az2.id]
  throughput_capacity = 64   # MB/s

  self_managed_active_directory {
    dns_ips     = ["10.0.1.10", "10.0.1.20"]
    domain_name = "corp.example.com"
    username    = "admin"
    password    = var.ad_password
  }

  deployment_type = "MULTI_AZ_1"  # HA across two AZs
  preferred_subnet_id = aws_subnet.private_az1.id

  aliases = ["fileserver.corp.example.com"]
}

Key capabilities: DFS Namespaces (namespace-based file paths), Windows ACLs and NTFS permissions, Shadow Copies (VSS-based backups accessible as previous versions), SMB encryption in transit.

resource "aws_fsx_ontap_file_system" "main" {
  storage_capacity    = 1024  # GB
  subnet_ids          = [aws_subnet.private_az1.id, aws_subnet.private_az2.id]
  preferred_subnet_id = aws_subnet.private_az1.id
  deployment_type     = "MULTI_AZ_1"
  throughput_capacity = 256

  fsx_admin_password = var.fsx_admin_password
}

EFS vs FSx: the decision

Choose EFS when:

• Linux workloads, POSIX file system, NFS
• Multiple instances need concurrent read-write access with automatic scaling
• Elastic throughput (Elastic mode) handles variable workload
• Operational simplicity matters over maximum performance

Choose FSx for Lustre when:

• HPC, ML training, financial modeling — workloads needing hundreds of GB/s
• Need S3 integration (lazy loading, export back)
• Scratch compute clusters that start/stop — scratch FSx deletes automatically

Choose FSx for Windows when:

• Windows applications requiring SMB, NTFS, or Windows ACLs
• Active Directory integration required
• Migrating on-premises Windows file servers

Choose FSx for ONTAP when:

• Multi-protocol access (NFS + SMB on same data)
• Enterprise data management (FlexClone, SnapMirror)
• Existing NetApp infrastructure being extended to AWS