Q. What are the improvements to Shared VHDX in Windows Server 2016?
A. Shared VHDX was introduced in Windows Server 2012 R2 and enables a VHDX file that is connected via the SCSI controller in a VM and stored on a CSV volume (either directly or via a scale-out file server) to be connected to multiple VMs and those VMs see the shared VHDX as shared storage allowing it to be used as cluster storage for guest VMs. In the initial release in 2012 R2 there were some features missing due to the nature of the VHDX being access by multiple VMs simultaneously which complicates many types of disk operation. In Windows Server 2016 many of these limitations have been removed and key features with shared VHDX now include:
- Dynamic resize (resizing while VMs are running)
- Host level backup
- Hyper-V Replica support
The only features that do not work with Shared VHDX currently in 2016 (but this could change) are checkpoints and storage migration.