Microsoft 365


Active Directory


Windows Server



Microsoft Azure

Replicating Between File Servers Using Azure File Sync

Aidan Finn



I explained how the components of Azure File Sync interconnect in The Architecture of Azure File Sync. When you deploy a sync agent to a file server, each replicated folder, referred to as a server endpoint, synchronizes to an Azure Files share, referred to as a cloud endpoint. This combination us referred to as a sync group. It is possible to have more than on server participate in a sync group. This allows us to synchronize folders between file servers, using Azure as the middle-man.

The file servers do not have to synchronize all folders to each other. For example, let’s pretend there are 3 file servers:

  • Chi-FS1
  • Dub-FS1
  • Syd-FS1

Chi-FS1 synchronizes:

  • “Chicago Files” to Azure only
  • “All Users” to Dub-FS1 and Syd-FS1 via Azure
  • “Sales” to Syd-FS1 via Azure

Dub-FS1 synchronizes:

  • “Dublin Files” to Azure only
  • “All Users” to Chi-FS1 and Syd-FS1 via Azure

Syd-FS1 synchronizes:

  • “Sydney Files” to Azure only
  • “All Users” to Chi-FS1 and Dub-FS1 via Azure
  • “Sales” to Chi-FS1 via Azure

Registering Additional File Servers

The process of adding a file server to an existing sync group re-does what is done to register the first file server. You will start by ensuring that the file server meets the requirements of Azure File Sync. Next you will:

  1. Install the Azure Resource Manager (Azure RM) PowerShell modules on the file server
  2. Download the Sync Agent from the Azure File Sync sync service and install it on the file server

The sync agent will need to be registered. This will require you to sign into your Azure Subscription in the registration wizard on the file server. Note that Cloud Solution Provider (CSP) customers must toggle a switch to say that they are using a CSP subscription, and copy/paste their tenant ID, which they can obtain from the Azure Portal (Azure AD > Properties > Directory ID). During the registration, you will select the subscription, resource group, and the sync service that contains the sync groups that this file server should join.
You should repeat the above process for each additional file server that you wish to register with this deployment of Azure File Sync. Note that there is an agent charge for each additional file server that you register with the sync service.

Adding Servers to Sync Groups

Once a server is registered, you can add it to existing synch groups. Open the sync service in the Azure Portal and browse to Sync Groups. For each sync group that you want to extend to the new file server, do the following:

  1. Open the sync group
  2. Click Add Server Endpoint
  3. In the Add Server Endpoint blade, select the newly registered server, enter the synchronization path on the file server, and optionally configure tiering

Adding more server endpoints to extend Azure File Sync replication to more file servers [Image Credit: Aidan Finn]

Adding more server endpoints to extend Azure File Sync replication to more file servers [Image Credit: Aidan Finn]

Note that a synchronized folder can reside in different locations on file servers. For example, “All Users” might be D:\All Users on Syd-FS1 and it might be on W:\Shares\Global on Dub-FS1.
A few minutes later, the folder will start to synchronize on the new file server. Even without tiering, all of the files will appear as reparse points or folders that redirect users to the cloud copies of the files, with the expected paths, names, and permissions; this allows users to start using the file server within a few minutes of being added to the sync group(s).

Article saved!

Access saved content from your profile page. View Saved