Azure File Sync

What it is

Azure File Sync keeps an on-premises Windows Server file server in sync with a cloud Azure file share. It centralizes your files in Azure while keeping a high-performance cache on the local server — a hybrid pattern for preferring cloud while staying on-prem.

Why it exists

You want cloud durability/central access but your line-of-business apps still need a local Windows file server mount + latency. File Sync gives one identity across local cloud-copied shares and enables the “primary data in Azure, cache on-prem” model.

Key ideas (the three pieces)

  1. Storage Sync Service — the top-level Azure resource that orchestrates sync.
  2. Sync group — defines what syncs to where (one cloud endpoint + one or more server endpoints).
  3. Cloud endpoint / Server endpoint — an Azure file share (cloud) and a folder on a registered Windows Server (server).
  • Cloud tiering: files can be tiered to the cloud — only a local pointer/heat-based stubs remain; cold files stay cloud-only and hydrate on demand, saving local disk.
  • Windows Server Failover Clustering, Distributed File System (DFS), Azure Backup integrate with it.

How it fits (diagram)

file-sync.svg

Exam notes

  • File Sync requires Windows Server server agents; it is not for Linux.
  • Cloud tiering offloads cold files to Azure → local space is reclaimed, files recall on access.
  • One sync group = one cloud endpoint + multiple server endpoints; many-to-one, one-to-many, multi-site.
  • Purpose: centralize in Azure Files while caching locally — you do NOT need a second manual copy job.

azure-files · storage-account · storage-browser

📘 Source: Microsoft Learn — File Sync