Microsoft Announces Nano Server

Last month, Editorial Director Jeff James here at the Petri IT Knowledgebase reported on some leaked slides from Microsoft that mentioned a version of Windows Server called Nano Server. Today, Microsoft made it official by announcing Nano Server.

What is Nano Server?

According to Microsoft, Nano server is described as a “deeply refactored version of Windows Server with a small footprint” that is designed for “the cloud and a DevOps workflow.” What does all that mean?
Nano Server is a headless installation of the next version of Windows Server, which is unofficially been referred to as Windows Server vNext. This means that, like Server Core, there is no UI. It’s Windows without the windows. Unlike Server Core, there is no command prompt, no PowerShell window, and there isn’t even a logon prompt, local or via Remote Desktop. This is a server operating system that you are not meant to log into!
You will not be using Nano Server for traditional workloads. Instead, Nano Server is a piece of infrastructure that enables services. There are two core scenarios for Nano Server:

  • Cloud infrastructure: Services such as Hyper-V, including Hyper-V cluster, and Scale-Out File Servers (SOFSs) can be deployed on Nano Server.
  • Born-in-the-cloud applications: Applications that are running in Containers (also announced today), virtual machines, or on many development platforms that do not require a UI on the server to manage them.

The concept of Nano Server is that you deploy what you need, something that Windows Server commentators have been requesting since the 1990s. The OS offers no functionality without components being enabled. You then manage the OS remotely using WMI, PowerShell, and presumably System Center vNext. Also omitted from Nano Server is 32-bit support, MSI, and a number of default Server Core components.
Microsoft states that the OS will be much smaller than a standard installation, comparing it to current Windows Server builds:

  • 93 percent lower VHD size
  • 92 percent fewer critical bulletins
  • 80 percent fewer reboots

Nano Server is not for everyone. The “treat your servers like cattle, not pets” concept that is espoused by Jeffrey Snover, Distinguished Engineer and Lead Architect at Microsoft, doesn’t account for the fact that some servers are sacred cows (credit to Didier Van Hoye). But for anyone working at cloud scales, Nano Server will offer a platform that is reduced in size, maintenance effort, and attack surface. And by including much less code, hopefully it will also have fewer complexities that lead to bugs.

I was briefed on Nano Server and I can tell you that Microsoft is very excited about the potential of Nano Server in larger deployments. Whether you’re running it for core cloud infrastructure or within virtual machines for cloud applications, Nano Server offers quite a bit of potential that, hopefully, Server Core was unable to deliver.