Azure File Sync Agent v9 Release – December 2019

Applies to: Azure


This article describes the improvements and issues thatare fixed in the Azure File Sync Agent v9 release that is dated December 2019. Additionally,this article contains installation instructions for the update.

Improvements and issues that are fixed

Self-service restore support
Support for larger file share sizes
  • Azure File Sync now supports up to 64TiB and 100 million files in a single, syncing namespace. 
Data Deduplication support on Server 2019
  • Data Deduplication is now supported with cloud tiering enabled on Windows Server 2019. To support Data Deduplication on volumes with cloud tiering, Windows update KB4520062 must be installed.
Improved minimum file size for a file to tier
  • The minimum file size for a file to tier is now based on the file system cluster size (double the file system cluster size). For example, by default, the NTFS file system cluster size is 4KB, the resulting minimum file size for a file to tier is 8KB.
Network connectivity test cmdlet
  • As part of Azure File Sync configuration, multiple service endpoints must be contacted. They each have their own DNS name that needs to be accessible to the server. These URLs are also specific to the region a server is registered to. Once a server is registered, the connectivity test cmdlet (PowerShell and Server Registration Utility) can be used to test communications with all URLs specific to this server. This cmdlet can help troubleshoot when incomplete communication prevents the server from fully working with Azure File Sync and it can be used to fine tune proxy and firewall configurations.
    • Torun the network connectivity test, run the following PowerShell commands:
      • Import-Module "<SyncAgentInstallPath>\StorageSync.Management.ServerCmdlets.dll"
      • Test-StorageSyncNetworkConnectivity
 Remove server endpoint improvement when cloud tieringis enabled
  • As before, removing a server endpoint does not result in removing files in the Azure file share. However, behavior for reparse points on the local server has changed. Reparse points (pointers to files that are not local on the server) are now deleted when removing a server endpoint. The fully cached files will remain on the server. This improvement was made to prevent orphaned tiered files when removing a server endpoint. If the server endpoint is recreated, the reparse points for the tiered files will be recreated on the server.
Performance and reliabilityimprovements
  • Reduced recall failures. Recall size is now automatically adjusted based on network bandwidth.
  • Improved download performance when adding a new server to a sync group.
  • Reduced files not syncing due to constraint conflicts.
  • Files fail to tier or are unexpectedly recalled in certain scenarios if the server endpoint path is a volume mount point.

More information about the azure file sync v9 release

  • Thisupdate is available for Windows Server 2012 R2, Windows Server 2016 and WindowsServer 2019 installations.
  • AzureFile Sync agent version or a later version is required to upgradeexisting agent installations.
  • Arestart may be required if files are in use during the agent installation.
  • The agent version for the v9 release is

How to obtain and install the azure file sync agent

Azure File Sync agent version 9.0 is no longer available due to an issue identified which can cause sync to fail with one of the following errors:
  • ​0x8e5e044e (JET_errWriteConflict)​
  • 0x8e5e0450 (JET_errInvalidSesid)​
  • 0x8e5e0442 (JET_errInstanceUnavailable)​
This issue has been fixed in the Azure File Sync agent v9.1 update

  • This issue only impact servers that have Azure File Sync agent version 9.0 installed. Azure File Sync agent version 8.0 and older are not impacted by this issue.