With Windows Server 2016, Microsoft aims to assist customers in modernising on-premise data centres, making it easier to move workloads out to its Azure public cloud. This means embracing trends such as containers and microservice architectures, as well as more general improvements including rolling upgrades for Hyper-V virtualisation and improved identity management.
Beta versions of the OS has been available since 2014, with a fourth technical preview released at the end of 2015, containing further enhancements to Nano Server, Windows Containers, Hyper-V and Storage Spaces Direct.
Microsoft has also revealed more details about Windows Server 2016 licensing, with customers paying per-core rather than per-processor when the service launches later this year. The move could mean that users will be paying more than expected - see the final section of this article for more information.
Uptake of the software is likely to be gradual as IT departments wait for initial bugs and other issues to be resolved. A recent Spiceworks survey of 300 IT professionals indicates that only 17 percent of respondents expect to roll out the new OS within the first year of release, with most opting to make the jump within two to three years. Forty-three percent had no fixed timeframe for an upgrade, with many still running Server 2003.
So what should you expect from Windows Server 2016 when it launches later this year? Here are some of the main features so far...
Windows Server 2016: Nano Server
The most eye-catching update is the introduction of Nano Server. Developed under the name ‘Tuva’, Nano Server is a scaled down, purpose-built operating system designed to run modern cloud applications and act as a platform for containers. It promises fewer patches and updates, faster restarts, better resource utilisation and, due to having fewer operating system components, tighter security.
Nano Server is essentially a significantly slimmed down version of Windows Server, Microsoft says.
It has a 93 percent lower VHD size than Windows Server, for example, as well as 92 percent fewer critical bulletins and 80 percent fewer reboots as a result of security patches. This has been achieved by, among other things, removing 32-bit support - it will only run 64-bit applications - while the graphical user interface (GUI) has also gone, with all management conducted either remotely via WMI or PowerShell.
It is focused on two areas. Firstly “born-in-the-cloud” applications, offering support for programming languages and runtimes including C#, Java, Node.js, and Python, whether running on containers, VMs, or bare metal physical servers. It will also target Microsoft Cloud Platform infrastructure, with support for “compute clusters running Hyper-V and storage clusters running Scale-out File Server”.
The third technical preview features a new Emergency Management Console which enables users to "view and fix networking configuration directly from the Nano Server console". There is also a PowerShell script for creating Nano Server virtual machines on the Azure cloud.
In the fourth technical preview, updatess include support for DNS Server and IIS server roles, while Microsoft has also created a PowerShell module to simplify the building of Nano Server images.
With the launch of the fourth preview Nano Server is now supported on Window Server Containers.
Windows Server 2016: Container support
Support for containers is another of the standout features, which will make it easier to adopt microservices architectures. Microsoft has already shown its interest in container technologies by announcing a partnership with open source project Docker in 2014, and Windows Server 2016 has continued to build on this.
Containers offer a lightweight alternative to full virtualisation and allow applications to be packaged and moved more easily from server to server. Although the technology has been around for some time - Microsoft and Google use containers in their own cloud operations, for instance - it has begun to be used more widely among all types of businesses.
In Windows Server 2016 Microsoft will offer support in different ways. The third technical preview offered the opportunity to get to grips with Windows Server Containers, which is part of the open source Docker project. Windows Server Containers can be deployed and managed either through the Docker Client or Microsoft’s PowerShell.
In addition to this, Microsoft is now offering a preview of its Hyper-V Containers, which it says will increase isolation and improve security by running containers inside a virtual machine.
Interestingly the Spiceworks report – which surveyed small, medium and large businesses - highlighted relatively muted interestin the virtualisation alternative. This is likely to due to container technology making less sense for smaller IT departments currently than those running large data centres.
Windows Server 2016: Hyper-V
Microsoft has also announced number of improvements to the core Hyper-V virtualisation platform first seen in Windows Server 2008. According to Spicework’s IT pro survey, new Hyper-V functionality is the most anticipated of all the new features.
Rolling upgrades will make it quicker and easier to migrate Hyper-V clusters to Windows Server 2016. Users will be able to add a node running the technical preview to a Hyper-V cluster already running Windows Server 2012 R2. The cluster will continue to operate at the Windows Server 2012 R2 feature level until all nodes are upgraded.
Other improvements include the ability to hot-add virtual network adapters and memory, a secure boot for Linux guest operating systems and support for nested virtualisation, which can now be used in dev/test scenarios.
A full list of the numerous updates and additions to Hyper-V as of the fourth technical preview – including improved PowerShell support for VM upgrades - can be seen here.
Windows Server 2016: Storage
Improvements to on-premise storage capabilities have been informed by its Azure platform, and Microsoft is eyeing what's called the 'software defined data centre' in an attempt to bring down costs of running private clouds.
The move into software defined storage began in Windows Server 2012 with the launch of Storage Spaces and Scale Out File Server and is continued in the latest versions of the OS.
For example, Storage Spaces Direct allows organisations to tap internal storage in standard servers, similar in some respects to VMware's vSAN, providing a pool of virtualised storage that can be easily scaled.
Another new feature in Windows Server Technical Preview is Storage Replica, which offers block-level synchronous replication between servers and clusters disaster recovery purposes.
Meanwhile, rolling upgrades also make it easier to upgrade storage clusters to Windows Server 2016 without any downtime.
The third technical preview has also revealed improvements to software defined networking tools, with SDN architecture from Microsoft Azure, including a scalable network controller and L4 load balancer.
The fourth preview added support for all-flash configurations with NVMe SSD and SATA SSD devices in Storage Spaces Direct, as well as other storage features such as improved health monitoring and monitoring capabilities.
More information on updates can be seen here.
Windows Server 2016: Licensing
At the end of 2015, Microsoft announced details on licensing arrangements for Windows Sever 2016. Customers will be required to pay per-core rather than per-processor when the service launches later this year. This mirrors a similar change with SQL Server licensing a few years back, and is likely to increase costs and complexity for users.
"Microsoft’s auditors likely will have a field day with these new requirements for Windows Server, in the same way that they have used the ever-more-complex licensing rules for SQL Server to increase the company’s audit-based revenue in recent years," Christopher Barnett, an associate attorney with Scott & Scott LLP, told IDG News Service.