Recently I installed Azure File Sync on a test file server and this is my experience.
Use Azure File Sync (preview) to centralize your organization’s file shares in Azure Files, while keeping the flexibility, performance, and compatibility of an on-premises file server. Azure File Sync transforms Windows Server into a quick cache of your Azure file share. You can use any protocol that’s available on Windows Server to access your data locally, including SMB, NFS, and FTPS. You can have as many caches as you need across the world.
Planning and deployment instructions are well described in the this Microsoft article. https://docs.microsoft.com/en-us/azure/storage/files/storage-sync-files-planning
Recall all tiered data
When enabled for a Server Endpoint, cloud tiering will tier files to your Azure File shares. This enables on-premises file shares to act as a cache, rather than a complete copy of the dataset, to make efficient use of the space on the file server. However, if a Server Endpoint is removed with tiered files still locally on the server, those files will become unaccessible. Therefore, if continued file access is desired, you must recall all tiered files from Azure Files before continuing with deregistration.
This can be done with the PowerShell cmdlet as shown below
Azure File Sync configured to free 50% of the local file share. (tiered data enabled)
Files with “APLO” attributes are tiered and “on-demand”
Changing Volume Free Space to 0% configures the local shares to store 100% data.
Use PowerShell preview command-lets to recall data that has been tiered to Azure File Sync
First Import PowerShell Module
Next use command-let to recall files
Once PowerShell command has finished, all files are stored locally.
Thank You for reading.