Azure File Sync Agent v5 Release – February 2019

Si applica a: Azure


This article describes the improvements and issues thatare fixed in the Azure File Sync Agent v5 release that is dated February 2019.Additionally, this article contains installation instructions for this release.

Improvements and issues that are fixed

  • Support for Azure Government cloud
    • We have added preview support for the Azure Government cloud. This requires a white-listed subscription and a special agent download from Microsoft. To get access to the preview, please email us directly at
  • Support for Data Deduplication
    • DataDeduplication is now fully supported with cloud tiering enabled on WindowsServer 2016 and Windows Server 2019. Enabling deduplication on a volume withcloud tiering enabled lets you cache more files on-premises withoutprovisioning more storage.
  • Support for offline data transfer (e.g. via Data Box)
    • Easilymigrate large amounts of data into Azure File Sync via any means you choose.You can choose Azure Data Box, AzCopy and even third party migration services.No need to use massive amounts of bandwidth to get your data into Azure, in thecase of Data Box – simply mail it there! To learn more, see Offline Data Transfer Docs.
  • Improved sync performance
    • Customerswith multiple server endpoints on the same volume may have experienced slowsync performance prior to this release. Azure File Sync creates a temporary VSSsnapshot once a day on the server to sync files that have open handles. Syncnow supports multiple server endpoints syncing on a volume when a VSS syncsession is active. No more waiting for a VSS sync session to complete so synccan resume on other server endpoints on the volume.
  • Improved monitoring in the portal
    • Charts have been added in the Storage Sync Service portal to view:
      • Number of files synced
      • Size of data transferred
      • Number of files not syncing
      • Size of data recalled
      • Server connectivity status
    • To learn more, see Monitor Azure File Sync.
  • Improvedscalability and reliability
    • Maximum number of file system objects (directories and files) in a directory has increased to 1,000,000. Previous limit was 200,000.
    • Syncwill try to resume data transfer rather than retransmitting when a transfer isinterrupted for large files

More information about the Azure File Sync Agent v5 release

  • The Azure File Sync agent is supported on Windows Server 2012 R2, Windows Server 2016, and Windows Server 2019.
  • Azure File Sync agent version or a later version is required to upgrade existing agent installations.
  • A restart may be required if files are in use during the installation.
  • The agent version for the v5 release is

How to obtain and install the Azure File Sync Agent

The Azure File Sync agent is available from MicrosoftUpdate, Microsoft Update Catalog, and Microsoft Download Center.

  • If the Azure File Sync agent is not currently installed on a server, use the agent installation package on the Microsoft Download Center. The agent installation package on Microsoft Update and Microsoft Update Catalog is intended for agent upgrades only.
  • To update existing agent installations, run AfsUpdater.exe (located in the agent installation directory) or download and install the update from Microsoft Update or Microsoft Update Catalog. 
Microsoft Update

To obtain and install from Microsoft Update, follow these steps on a server that has Azure File Sync agentinstalled:

Server 2016 and Server 2019

  1. Click Start, and then click Settings.
  2. In Settings, click Update & security.
  3. In the Windows Update window, click Check online for updates from Microsoft Update.
  4. Verify the update is listed and then click Install now.

Server 2012 R2

  1. Click Start, and then click Control Panel.
  2. In Control Panel, double-click Windows Update.
  3. In the Windows Update window, click Check for updates.
  4. Click Important updates are available.
  5. Verify the update is selected, and then click Install.

Microsoft Update Catalog

Go to the following website to manually download this update from the Microsoft Update Catalog:

Azure File Sync Agent v5 release: February 2019 (KB4459989)

To manuallyinstall the update package, run the following command from an elevated commandprompt:

  • msiexec.exe /p packagename.msp REINSTALLMODE=OMUS REINSTALL=StorageSyncAgent,StorageSyncAgentAzureFileSync,StorageSyncAgentGuardFilter,StorageSyncAgentUpdater /qb /l*v KB4459989.log

For example, toinstall the Azure File Sync agent update for Server 2016, run the followingcommand:

  • msiexec.exe /pStorageSyncAgent_WS2016_KB4459989.mspREINSTALLMODE=OMUS REINSTALL=StorageSyncAgent,StorageSyncAgentAzureFileSync,StorageSyncAgentGuardFilter,StorageSyncAgentUpdater /qb /l*v KB4459989.log

Microsoft Download Center

Go to the Microsoft Download Center tomanually download the full installer release of Azure File Sync Agent v5 release.

How to perform a silentinstallation for a new agent installation

To perform a silent installation for a new agentinstallation that uses the default settings, run the following command at anelevated command prompt:

  • msiexec /i packagename.msi /qb/l*v AFSv5Installer.log

For example, to install the Azure File Sync agentfor Windows Server 2016, run the following command: 

  • msiexec /i StorageSyncAgent_V5_WS2016.msi/qb /l*v AFSv5Installer.log 

Note Use the /qb switch to display restart prompts(if required), agent update, and server registration screens. To suppress thescreens and automatically restart the server (if required), use the /qn switch.

Note: To perform a silent installation withcustom settings, follow the steps documented in KB4459986.