Users Guide

Figure 30. Visibility in PowerShell
Configuring NVDIMM-N for Hyper-V Virtual Machines
The article referenced here, Cmdlets for configuring persistent memory devices for Hyper-V VMs, provides details about
configuring Hyper-V VMs with JEDEC compliant NVDIMM-N.
NVDIMM-N RO Behavior
Windows Server 2019
By design, Windows Server 2019 manages NVDIMM-N in a manner that differs from that of Windows Server 2016. In Windows
Server 2016, if an NVDIMM-N that is in read/write mode loses power, it goes into read-only mode.
But in Windows Server 2019, if an NVDIMM-N that is in read/write mode loses power, it continues to function in read/write
mode.
Similarly, if the NVDIMM-N modules are forced to Read Only through the BIOS Setup Menu or through any module related
failures, these devices would still be read/write accessible under Windows Server 2019.
To make Windows Server 2019 manage NVDIMM-N in the same way as Windows Server 2016 RTM, a registry entry needs to
modified.
For details refer to https://support.microsoft.com/en-us/help/4492760/nvdimm-in-read-write-mode-after-backup-power-
removed-in-windows-server
Windows Errata
The following errata affects Windows OSes and are expected to be fixed in a future OS patch.
● In Windows Server 2016, the Storage Spaces GUI shows NVDIMM-N bus type as UNKNOWN. It doesn't have any
functionality loss or inability in creation of Pool, Storage VD
● Windows Server 2016 and Windows 10 Anniversary Edition do not support interleaved sets of NVDIMM-Ns
● Hyper-V role in Windows Server 2016 and Windows 10 Anniversary Edition do not support NVDIMM-Ns, i.e., NVDIMM-N
cannot be directly exposed to VMs.
● When a namespace is created in Windows Server 2019 (WS2019), the logged message appears as "The driver for
persistent memory disk encounters internal error". The error is expected and it may occur during testing
of Storage Class Memory (SCM) device. This means the namespace is created, and is considered as WAD for WS2019.
Windows
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