Hello Windows Insiders!

Today we are very excited to be releasing Windows Server Insider Preview Build 16257 to Windows Insiders. To access, register at the Windows Insiders for Business program or the Windows Insider program and then navigate to the Windows Server Insider Preview download page.

This release also includes the Remote Server Administration Tools (RSAT) packages. When installed on a Windows 10 client, RSAT allows a user to remotely manage and administer Insider builds of Windows Server via GUI tools. Valid on Windows 10 client builds greater than 16250.

General Scenario Highlights

Developers and Containers:

New base container images (available on Windows Insider Docker Hub repo) Optimized Nano Server base image (over 70% smaller) The .NET team is providing a preview image based on Nano Server with .NET Core 2.0 The PowerShell team is providing a preview image based on PowerShell 6.0 Optimized Server Core base image (over 20% smaller)

Support for SMB volume mounting

Infrastructure for Orchestrators Networking enhancements for ongoing Kubernetes work Named pipe mapping support

Bug fixes, performance enhancements

Cloud Guest:

IIS TLS info: administrators can make specific recommendations to default to HTTPS

Disaster Recovery Storage Replica Test Failover

Guest + Host better together vPMEM in Guest: Tenants can use and manage PMEM/SCM Tenant-Aware VM Start Ordering: App Ready / OS Heartbeat for better load balancing Guest RDMA

Improvement in time accuracy

Azure enlightened clusters – optimized to run on Azure IaaS

Cloud Host:

Software Defined Data Center (SDDC) host Security Shielded Linux VM SDN: Encrypted virtual networks Secure clusters SMB 1 disabled by default Resiliency and Availability SDN: Reduced downtime for tenant connections through gateways Spaces Direct: Scoped Spaces to mitigate impact of multi-node loss Spaces Direct: Marginal drive handling for predictive detection of drive failures Efficiency Data Deduplication available for ReFS New Data Deduplication DataPort API for optimized ingress/egress Space efficiency with ReFS Compaction Performant Spaces Direct Multi Resilient Volumes (MRV) Hyper-converged Scale Cluster Sets: Significantly increases hyper-converged SDDC cloud scale by grouping multiple clusters into a larger fabric Hardware support Support for Storage Class Memory (SCM) in Spaces Direct



What’s New in Build 16257 for Windows Server

Windows Subsystem for Linux (WSL) is available on Windows Server

Windows Subsystem for Linux (WSL) is now available on Windows Server along with a compliment of Linux distributions.

Test WSL on Windows Server. WSL runs unmodified Linux (ELF64) binaries natively. With the additions of WSL you can run node.js, Ruby, Python, Perl, Bash scripts or other tools that expect Linux behaviors, environment, or filesystem-layout, the ability to install and run Linux with WSL expands the tools at your disposal on Windows Server.

At this time, WSL does not support persistent Linux services (such as daemons and jobs) as background tasks. To enable WSL and install a Linux distribution, see Enable the Windows Subsystem for Linux and Install a Linux distribution in the Windows Server 2016 Installation Guide on GitHub.

Read more in this blog or follow the installation guide to try it out.

How to Download

The latest Windows Server build and matching symbols are available for download here. Matching Windows Server container images will be available via the Docker Hub. For more information about Windows Server containers and Insider builds, please visit http://aka.ms/containers/insiders.

The following keys are available for unlimited activations of Windows Server. These keys may be used throughout the pre-release cycle.

Server Datacenter Core: B69WH-PRNHK-BXVK3-P9XF7-XD84W

B69WH-PRNHK-BXVK3-P9XF7-XD84W Server Standard Core: V6N4W-86M3X-J77X3-JF6XW-D9PRV

NOTE: If you signed up for Windows Insiders for Business using an AAD account, there is a temporary issue with access to the Windows Server Download page using AAD accounts. If you registered using an MSA account at the Windows Insider program, your MSA account may be used to access the page and to download builds until this is resolved.

It’s all about your feedback!

Use the Feedback Hub app to provide feedback on Windows Server builds. Feedback Hub comes pre-installed on Windows 10. Register a Windows 10 device with the Windows Insider or Windows Insider for Business programs. Open the Feedback Hub application. Choose the Server category and then the appropriate subcategory for your feedback. Please indicate what edition and build number you are providing feedback on. The Feedback Hub app cannot scan a server for diagnostic information, however you may manually attach screenshots or other files to your feedback entry.

We encourage you to visit the Windows Server Insiders space on the Microsoft Tech Communities forum to collaborate, share and learn from experts.

The expiration date for this server preview build is 12/4/2017.

Known issues

The background tasks infrastructure service (Bisrv.dll) may cause a system crash because of a null class pointer read error (0xC0000005) or a failfast corrupt list entry (0xC0000409) during a Distributed Component Object Model (DCOM) launch, or because of a critical process bug check (error code 0xC0000409, bug check 0xEF) in the host process for Windows services (Svchost.exe).

Calling into the firewall service may hang: Apps that call into the firewall, such apps that use networking, may become unresponsive until the user reboots because of an application hang end-task error (0xCFFFFFFF) in the Windows firewall API library (FirewallAPI.dll), which occurs when the library is blocked on an advanced local procedure call (ALPC) port while attempting to diagnose a connection failure and retrieve information.

Cluster Sets: A couple of key functionalities to enable end-to-end testing of Cluster Sets scenarios are not present in this build, so defer all evaluation of this scenario to a future build.

Bugcheck during volume creation: A stop error may occur during volume creation in a cluster. The recommended workaround is, after restarting the computer, to delete the volume and try creation again.

Bugcheck during volume repair: A stop error may occur during volume repair in a cluster. The recommended workaround is to restart the computer. No corruption or data loss is expected.

No downtime for Hustle-As-A-Service,

Dona <3