S3 File Gateway
- What it is
- The AWS Storage Gateway mode that presents Amazon S3 as an ordinary NFS or SMB file share to on-premises applications.
- How it works
- Each file written to the share becomes a single S3 object, one-to-one, readable by any other S3 client.
- Frequently used files are cached locally for low-latency reads; everything is stored durably in S3.
- Why it matters
- Legacy applications that only speak file protocols get cloud storage without a rewrite.
- Once objects are in S3, lifecycle policies can transition them into the Amazon S3 Glacier classes.
- Not to be confused with
- FSx File Gateway — SMB access to Amazon FSx for Windows File Server, not to S3.
- Volume Gateway — block (iSCSI) volumes, not a file share.
- Exam signal
- “NFS/SMB share backed by S3 objects” → S3 File Gateway.