---
title: "Reference"
slug: "dev-datastore-reference"
updated: 2026-10-28T02:15:22Z
published: 2026-10-28T02:15:22Z
canonical: "docs.vastdata.com/dev-datastore-reference"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.vastdata.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Reference

What VAST Cluster 5.5 supports and where it differs from AWS. Start with S3 compatibility and Limits; the NFS reference and SMB reference cover the file protocols.

- **[S3 compatibility](/develop/docs/dev-datastore-reference-s3-compatibility)**: Supported S3 requests and headers on VAST Cluster 5.5, the differences from AWS S3 that affect applications, and VAST additions.
- **[Limits](/develop/docs/dev-datastore-reference-limits)**: Size and count limits for bucket names, object keys, parts, tags, NFS file names and VAST Catalog on VAST Cluster 5.5.
- **[NFS reference](/develop/docs/dev-datastore-reference-nfs)**: Which NFS versions and features VAST Cluster 5.5 supports for clients, plus the access rules and name rules that affect them.
- **[SMB reference](/develop/docs/dev-datastore-reference-smb)**: How SMB 2.1 and 3.0 meet S3 and NFS on the same data: Active Directory, shared identities and security flavors.