1. Nano Server
Without a doubt the biggest change in Windows server is the new Nano Server. Nano Server is a pared down headless version of Windows Server. Nano Server will have a 93% smaller VHD size, 92% fewer critical bulletins and 80% fewer required reboots. Nano Server is a Windows Server installation options and it’s completely headless – there’s no GUI and no command prompt. Nano Server is designed to run Hyper-V, Hyper-V cluster, and Scale-Out File Servers (SOFSs) and cloud service applications. You can find out more about Nano Server at What You Need to Know about Microsoft Nano Server.
2. Windows Server Containers and Hyper-V Containers
The next biggest change in Windows Server 2016 will be support for containers. Containers are the latest buzz in IT technology as they threaten to supplant virtualization as a core IT technology. Containers enable you to isolate your applications from the underlying OS improving the deployment and reliability of those applications. Windows Server 2016 will provide two kinds of native containers: Windows Server Containers and Hyper-V Containers. Windows Server Containers are isolated from each other but they run directly on the Windows Server 2016 OS. Hyper-V Containers provide enhanced isolation by running the containers from a Hyper-V VM. The current preview release doesn’t support containers yet.
8. Linux Secure Boot
Another new feature in Windows Server 2016 Hyper-V is the ability to enable secure boot for VMs with Linux guest operating systems. Secure Boot is a feature of the UEFI firmware specification incorporated in Generation 2 VMs that protects the VM’s hardware kernel mode code from being attacked by root kits and other boot-time malware. Previously, Generation 2 VMs supported Secure Boot for Windows 8/8.1 and Windows Server 2012 VMs but not VM’s running Linux.
7. PowerShell Direct
PowerShell is a great management automation tool but it can be complicated to get it to run remotely against your VMs. You need to worry about security policies, firewall configurations and your host networking configuration. PowerShell Direct enables you to run PowerShell commands in the guest OS of a VM without needing to go through the network layers. Like VMConnect (the remote console support provided by the Hyper-V Manager) it requires zero configuration it connects directly to the guest VM and all you need are authentication credentials for the VM’s guest OS. You can learn more about PowerShell Direct at the Virtualization Blog.
6. Nested virtualization
Added primarily for the new container support, Windows Server 2016’s nested virtualization capabilities will also be a handy addition for training and lab scenarios. With this new feature you are no longer limited to running the Hyper-V role on a physical server. Nested virtualization enables you to run Hyper-V within a Hyper-V virtual machine.
5. Hot add & remove of virtual memory network adapters
Another great new feature in Windows Server 2016 Hyper-V is the ability to add and remove virtual memory and virtual network adapters while the virtual machine is running. In previous releases you need to use dynamic memory to change the minimum and maximum RAM settings of a VM that is running. Windows Server 2016 enables you to change the allocated RAM while the VM is active even if the VM is using static memory. Likewise, you add and remove network adapters while VM is running.
10. Storage Spaces Direct
Windows Server 2016 also has a number of storage system improvements one of the most important is the new Storage Spaces Direct feature. Storage Spaces Direct is the evolution of the previous Storage Spaces technology found in Windows Server 2012 R2. Windows Server 2016 Storage Spaces Direct allows a cluster to access JBOD storage in an external enclosure like Windows Server 2012 R2 or it can also allow access to JBOD and SAS disks that are internal to the cluster nodes. Like the previous release Store Spaces form the basis for Storage Pools and they support both SSD and HDD disks and data tiering. You can learn more about Store Spaces direct from John Savill’s article What is Storage Spaces Direct?
9. New Host Guardian Service and Shielded VMs
The Host Guardian Service is a new role in Windows Server 2016 that enables shielded virtual machines and protects the data on them from unauthorized access – even from Hyper-V administrators. Shielded VMs can be created using the Azure Management Pack Portal. Standard VMs can also be converted to Shielded VMs. With Shielded VMs Hyper-V virtual disks can be encrypted with BitLocker. For more information check out Shielded Virtual Machines in Windows Server.
4. Rolling upgrades for Hyper-V and Storage clusters
One of the biggest new changes for Hyper-V in Windows Server 2016 is rolling upgrades for Hyper-V clusters. The new rolling upgrades feature allows you to add a new Windows Server 2016 node to a Hyper-V cluster with nodes that are running Windows Server 2012 R2. The cluster will continue to run at the Windows Server 2012 R2 functional level until all of the cluster nodes have been upgraded to Windows Server 2016. When the cluster has mixed level nodes the management must be done from Windows Server 2016 or Windows 10. New VMs on a mixed cluster will be compatible with the Windows Server 2012 R2 feature set.