Unsupported features, limits, and quotas - Amazon Simple Storage Service
Unsupported S3 featuresFile system limitationsQuotasUnsupported NFS features

Unsupported features, limits, and quotas

This page describes the limitations and quotas when using S3 Files.

Unsupported S3 features

  • Archival storage classes – Objects in the S3 Glacier Flexible Retrieval or S3 Glacier Deep Archive storage classes cannot be accessed through the file system. Similarly, objects in the S3 Intelligent-Tiering Archive Access or Deep Archive Access tiers cannot be accessed through the file system. You must first restore these objects using the S3 API.

  • S3 Access Control Lists (ACLs) – S3 ACLs are not preserved after changes are made through the file system. We recommend that you keep ACLs disabled and use policies to control access to all objects in your bucket, regardless of who uploaded the objects to your bucket. For more information, see Managing access with ACLs.

  • Custom S3 object metadata – Custom user-defined metadata on S3 objects is not preserved after changes are made through the file system.

File system limitations

  • Hard links – S3 Files does not support hard links. Each file in the file system corresponds to a single S3 object key.

  • Path component size – S3 Files does not support objects where any single directory or file name in the path exceeds 255 bytes. A path component is a directory or file name derived from an S3 object key. For example, the key dir1/dir2/file.txt has three path components: dir1, dir2, and file.txt.

  • S3 key size limit – Files or directories whose full path name exceeds the 1,024-byte S3 object key size limit cannot be exported to S3.

  • Symlink targets – If an S3 object is a symlink, its target must be a valid path that is not empty and does not exceed 4,080 bytes.

  • POSIX permissions metadata size – Files or directories where the POSIX permission metadata exceeds 2 KB cannot be exported to S3.

Quotas

The following quotas can be increased by contacting AWS Support.

Resource Default quota
File systems per AWS account 1,000
Access points per file system 10,000

To request an increase, open the AWS Support Center, choose Create Case, then choose Service Limit Increase.

The following quotas cannot be changed.

Resource Quota
Connections per file system 25,000
Mount targets per file system per Availability Zone 1
Security groups per mount target 5
Tags per file system 50
VPCs per file system 1

There are also quotas specific to individual file systems.

Resource Quota
Maximum file size 52,673,613,135,872 bytes (48 TiB)
Maximum directory depth 1,000 levels
Maximum file name length 255 bytes
Maximum symlink target length 4,080 bytes
Maximum S3 object key length 1,024 bytes
Maximum open files per client 32,768
Maximum active user accounts per client 128
Maximum locks per file 512 across all connected instances
Maximum locks per mount 8,192 across up to 256 file-process pairs
File system policy size limit 20,000 characters

Unsupported NFS features

S3 Files supports NFSv4.1 and NFSv4.2, with the following exceptions:

  • pNFS

  • Client delegation or callbacks

  • Mandatory locking (all locks are advisory)

  • Deny share

  • Access control lists (ACLs)

  • Kerberos-based security

  • NFSv4.1 data retention

  • SetUID on directories

  • Block devices, character devices, attribute directories, and named attributes

  • The nconnect mount option