@Leif Johansson Adding more information to the @SUNOJ KUMAR YELURU suggestion: To transfer large numbers of files to Azure Files, we recommend that you use AzCopy (for Windows; in preview for Linux and UNIX) or Azure PowerShell. These tools have been optimized for network transfer.
Azure File Sync does not impose an additional hard limit.
You can also "Monitor Azure File Sync" performance, flexibility and more
If you come across any performance issue or lists some common problems related to Azure file shares. It provides potential causes and workarounds for when you encounter these problems. https://learn.microsoft.com/en-us/azure/storage/files/storage-troubleshooting-files-performance
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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