Microsoft Announces First Windows Server 2016 Insider Preview

During its Build 2017 conference in May, Microsoft announced that Windows Server would be joining the Windows insider program, which allows users to download and test pre-release builds containing new features that are not available to the general public. Making good on that promise, Microsoft has now made available the first preview build of Windows Server (build 16237) to Insiders.

To access the preview build, users need to register at the Windows Insiders for Business program or the Windows Insider program—either one will suffice. After doing that, interested users can download the first preview of the feature release to Windows Server 2016, which is expected to be available to the public in September.


This first test build includes new base container images (available on Windows Insider Docker Hub repo) for Nano Server and Server Core. The optimized Nano Server is over 70 percent smaller, Microsoft says, and comes with .NET Core 2.0 and a preview image based on PowerShell 6.0. As for the Server Core base image, it is over 20 percent small, Microsoft notes in a blog post.

Support for SMB volume mounting is part of this preview build, along with some changes made to Cloud Guest and Cloud Host, such as data duplication being available for ReFS and support for Storage Class Memory (SCM) in Spaces Direct. Also new is that Persistent Memory can now be exposed to Hyper-V virtual machines. Some related notes direct from Microsoft:

• In this build, NTFS-formatted direct access volumes that are created on non-volatile DIMMs can now be exposed Hyper-V VMs. This enables Hyper-V VMs to leverage the low-latency performance benefits of Persistent Memory devices.
• Virtualized Persistent Memory (vPMEM) is enabled by creating a VHD file (.vhdpmem) on a direct access volume on a host, adding a vPMEM Controller to a VM, and adding the created device (.vhdpmem) to a VM. Using vhdpmem files on direct access volumes on a host to back vPMEM enables allocation flexibility and leverages a familiar management model for adding disks to VMs.
• PowerShell can be used for the creation and management of Virtualized Persistent Memory.

Other additions and improvements include the ability to enable and disable battery passthrough, the ability to enable encryption for virtual network subnets, a two-fold throughput improvement for single connection TCP and UDP performance in low latency intra-datacenter scenarios, SSL throttling to enable predictable service for established connections (in the face of high incoming SSL traffic), improvements in time accuracy, and of course the usual round of bug fixes and general performance tweaks.