Kubernetes 1.5 Adds Support for Windows Server

--- title: " Windows Server Support Comes to Kubernetes " date: 2016-12-21 slug: windows-server-support-kubernetes url: /blog/2016/12/Windows-Server-Support-Kubernetes author: > [Michael Michael](https://twitter.com/michmike77) (Apprenda) --- _**Editor's note:** this post is part of a [series of in-depth articles](/blog/2016/12/five-days-of-kubernetes-1-5/) on what's new in Kubernetes 1.5_ Extending on the theme of giving users choice, [Kubernetes 1.5 release](https://kubernetes.io/blog/2016/12/kubernetes-1-5-supporting-production-workloads/) includes the support for Windows Servers. WIth more than [80%](http://www.gartner.com/document/3446217) of enterprise apps running Java on Linux or .Net on Windows, Kubernetes is previewing capabilities that extends its reach to the mass majority of enterprise workloads.  The new Kubernetes Windows Server 2016 and Windows Container support includes public preview with the following features: - **Containerized Multiplatform Applications** - Applications developed in operating system neutral languages like Go and .NET Core were previously impossible to orchestrate between Linux and Windows. Now, with support for Windows Server 2016 in Kubernetes, such applications can be deployed on both Windows Server as well as Linux, giving the developer choice of the operating system runtime. This capability has been desired by customers for almost two decades.  - **Support for Both Windows Server Containers and Hyper-V Containers** - There are two types of containers in Windows Server 2016. Windows Containers is similar to Docker containers on Linux, and uses kernel sharing. The other, called Hyper-V Containers, is more lightweight than a virtual machine while at the same time offering greater isolation, its own copy of the kernel, and direct memory assignment. Kubernetes can orchestrate both these types of containers.  - **Expanded Ecosystem of Applications** - One of the key drivers of introducing Windows Server support in Kubernetes is to expand the ecosystem of applications supported by Kubernetes: IIS, .NET, Windows Services, ASP.NET, .NET Core, are some of the application types that can now be orchestrated by Kubernetes, running inside a container on Windows Server. - **Coverage for Heterogeneous Data Centers** - Organizations already use Kubernetes to host tens of thousands of application instances across Global 2000 and Fortune 500. This will allow them to expand Kubernetes to the large footprint of Windows Server.  The process to bring Windows Server to Kubernetes has been a truly multi-vendor effort and championed by the [Windows Special Interest Group (SIG)](https://github.com/kubernetes/community/blob/master/sig-windows/README.md) - Apprenda, Google, Red Hat and Microsoft were all involved in bringing Kubernetes to Windows Server. On the community effort to bring Kubernetes to Windows Server, Taylor Brown, Principal Program Manager at Microsoft stated that “This new Kubernetes community work furthers Windows Server container support options for popular orchestrators, reinforcing Microsoft’s commitment to choice and flexibility for both Windows and Linux ecosystems.” **Guidance for Current Usage** | Where to use Windows Server support? | Right now organizations should start testing Kubernetes on Windows Server and provide feedback. Most organizations take months to set up hardened production environments and general availability should be available in next few releases of Kubernetes. | | What works? | Most of the Kubernetes constructs, such as Pods, Services, Labels, etc. work with Windows Containers. | | What doesn’t work yet? | - Pod abstraction is not same due to networking namespaces. Net result is that Windows containers in a single POD cannot communicate over localhost. Linux containers can share networking stack by placing them in the same network namespace. - DNS capabilities are not fully implemented - UDP is not supported inside a container

Kubernetes 1.5 introduces support for Windows Server 2016, enabling the orchestration of .NET and other Windows-based applications alongside Linux-based applications. This includes support for both Windows Server Containers and Hyper-V Containers, expanding the ecosystem of applications and covering heterogeneous data centers. While not yet production-ready, users are encouraged to test and provide feedback.