Datastore

The datastore is a VHDx formatted ReFS volume where the server keeps vDisks and other files. The local disk volume where the datastore will be placed and mounted is set at installation time, you can modify this location at any moment in the administration console.

The local disk volume hosting the datastore must have enough space to grow, you can either use SSD or mechanical disks. Expect longer times for I/O operations like compressing or compacting in mechanical disks but you may choose these disks due to bigger sizes available.

info

Block-cloning is used in merging or other I/O operations, making a copy operation very fast as only references to data are used and not the actual data. Block-cloning will not be used on deduplicated volumes.

Saving space

When a vDisk is deleted, the space in the datastore is not immediately released, a compact operation in the datastore must be performed. You can schedule compacting the datastore in the server's configuration in the administration console.

The Compact Datastore schedule is much more efficient than a regular compact VHDx operation, as it zeroes and trims all free space.

If you are running a Windows Server 2019 or later edition, you can enable deduplication in the datastore's mounted volume, this will be specially benefitial since many files in the vDisks are the same, and therefore reducing the size on disk of redundant data. Data Deduplication optimizes redundancies without compromising data fidelity or integrity.

tip

If you are using Branchcache in the same server, all of the deduplicated files are already indexed and hashed. Therefore, requests for data from a branch office are quickly computed.

ReFS versions

ReFS is the file system of the datastore providing data integrity with resiliency to corruption and block-cloning to immediate copy operations. Windows editions use different ReFS versioning, the datastore will be automatically converted to the version used in the operating system where is mounted, it's not backwards compatible meaning you cannot move the VHDx datastore file to a previous ReFS system on another system.

Some of the ReFS versions by Windows edition.

Windows Edition	ReFS version
Windows 11 23H2	3.9
Windows 2022	3.7
Windows 10 22H2	3.4
Windows 2019	3.4
Windows 2016	3.1

tip

For example if you mount a ReFS 3.7 volume on a ReFS 3.1 compatible windows, you will see a RAW partition instead of the ReFS volume, you may need to manually copy the files after a fresh installation of the Host Provisioning server.

Moving datastore location

Follow these steps to modify the path in your local hard disk where the datastore is placed.

• In the administration console, go to Nodes and edit the server you want to modify.
• Change the Datastore VHDx Path configuration with the new location, ending with a backslash '\', e.g. D:\
• Stop Host Provisioning Server application in the IIS console or run iisreset /stop in an elevated command prompt to completely stop IIS and all applications.
• Stop Host Provisioning Helper service using the services.msc console or running in an elevated command prompt net stop HPSHelper
• Run the disk management console diskmgmt.msc and detach the DatastoreHPS64K.vhdx by right clicking on the disk and selecting Detach.
• Move the DatastoreHPS64K.vhdx to the new location.
• Start the Host Provisioning Helper service, e.g. net start HPSHelper
• Start Host Provisioning Server application in the IIS console or run iisreset /start if you previously stopped IIS.