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Announcing Windows Server vNext Preview Build 20206

Written By published September 2, 2020

Hello Windows Insiders!

Today we are pleased to release a new build of the Windows Server vNext Long-Term Servicing Channel (LTSC) release that contains both the Desktop Experience and Server Core installation options for Datacenter and Standard editions.

What’s New

File Services: SMB improvements

We’ve expanded the SMB 3.1.1 protocol in Windows Server vNext with a number of security and performance capabilities, including:

  • AES-256 – Windows Server now supports AES-256-GCM and AES-256-CCM cryptographic suites for SMB Encryption. Windows will automatically negotiate this more advanced cipher method when connecting to another computer that supports it, and can also be mandated through Group Policy. Windows Server still supports AES-128 for down-level compatibility.
  • Compression – You can now copy files over SMB with compression using the Robocopy /compress and Xcopy /compress If the destination computer supports SMB compression and the files being copied are compressible, you should see significant performance improvements. For more information and a demo of this behavior, visit the ITOps Talk Blog. Any patched Windows Server 2019 and Windows 10 computers already support compression; now you will have command-line tools to make use of it.
  • RDMA encryption – SMB Direct over RMDA networks now supports encryption. Previously, enabling SMB Encryption would disable direct data placement, making RDMA performance as slow as TCP. Now data is encrypted before placement, leading to relatively minor performance degradation while adding AES-256 protected packet privacy.
  • East-West storage encryption – Windows Server failover clusters now support granular control of encrypting and signing intra-node storage communications for Cluster Shared Volumes (CSV) and the storage bus layer (SBL). This means that when using Storage Spaces Direct, you can decide to encrypt or sign east-west communications within the cluster itself for higher security.

Storage Migration Services improvements

Today marks our introduction of third generation of Storage Migration Service improvements, including:

  • AFS Tiering support preview – SMS now supports migrating data to a server configured with Azure File Sync cloud tiering, which allows you to overprovision storage while dehydrating data to Azure Files in the cloud. SMS now understands this scenario and can slow or pause transfers to allow AFS to catch up in it tiering to the cloud. This feature also makes changes to the SMS extension in Windows Admin Center, which will release separately to the feed at a later date. Please follow the Microsoft FileCab blog for updates.
  • Scenarios backported to Windows Server 2019 are included – Cluster, Samba-Linux migration support, Local security principal migration, and Inter-network migration were all added as backported features to Windows Server 2019 since its release. If you had not patched, you would not have access to them. They are now included out-of-the-box in Windows Server vNext.

We have also recently completed two new customer-requested Storage Migration Service scenarios and will be releasing them to Insiders in the coming months. Check the release notes and the Microsoft FileCab blog for updates.

Available Content

  • Windows Server vNext Long-Term Servicing Channel Preview is available in ISO format in 18 languages, and in VHDX format in English only. The following keys allow for unlimited activations:
    • Standard: MFY9F-XBN2F-TYFMP-CCV49-RMYVH
    • Datacenter: 2KNJJ-33Y9H-2GXGX-KMQWH-G6H67
  • Windows Server vNext Semi-Annual Preview The Server Core Datacenter and Standard Editions are available in the 18 supported Server languages in ISO format and in VHDX format in English only. The following keys allow for unlimited activations:
    • Standard: V6N4W-86M3X-J77X3-JF6XW-D9PRV
    • Datacenter: B69WH-PRNHK-BXVK3-P9XF7-XD84W
  • Windows Server Core App Compatibility FoD Preview
  • Microsoft Server Operating System Language Packs

Keys are valid for preview builds only. After activation for the preview keys is disabled, you may still install and use preview builds for development and testing purposes without activating.

These previews expire January 31 , 2021.

How to Download

Registered Insiders may navigate directly to the Windows Server Insider Preview download page.  See the Additional Downloads dropdown for Windows Admin Center and other supplemental apps and products. If you have not yet registered as an Insider, see GETTING STARTED WITH SERVER on the Windows Insiders for Business portal.

We value your feedback!

The most important part of a frequent release cycle is to hear what’s working and what needs to be improved, so your feedback is extremely valued. For Windows Server, use your registered Windows 10 Insider device and use the Feedback Hub application. In the app, choose the Windows Server category and then the appropriate subcategory for your feedback. In the title of the Feedback, please indicate the build number you are providing feedback as shown below:

[Server #####] Title of my feedback

See Share Feedback on Windows Server via Feedback Hub for specifics. We also encourage you to visit the Windows Server Insiders space on the Microsoft Tech Communities forum to collaborate, share and learn from experts.

For Windows Admin Center, Send us feedback via UserVoice. We also encourage you to visit the Windows Admin Center space on the Microsoft Tech Communities.

Diagnostic and Usage Information

Microsoft collects this information over the internet to help keep Windows secure and up to date, troubleshoot problems, and make product improvements. Microsoft server operating systems can be configured to turn diagnostic data off, send Required diagnostic data, or send Optional diagnostic data. The default setting is to send Required diagnostic data. Required diagnostic data includes information to help keep the device secure, up-to-date, and working as expected.  During previews, Microsoft asks that you change this setting to Enhanced in order to provide the best automatic feedback and help us improve the final product.

Administrators can change the level of information collection through Settings. For details, see Also see the Microsoft Privacy Statement.

Terms of Use

This is pre-release software – it is provided for use “as-is” and is not supported in production environments. Users are responsible for installing any updates made available from Windows Update.   All pre-release software made available to you via the Windows Server Insider program are governed by the Insider Terms of Use.