Hyper-V is Microsoft’s current generation hypervisor. Unlike earlier Microsoft virtualization solutions, such as Virtual PC, Hyper-V uses hardware assisted virtualization. This means that virtual machines do not require hardware emulation (except in special circumstances), and instead communicates directly with the underlying hardware.
Consequently, a virtual machine running on Hyper-V is able to perform as well as an operating system that has been natively installed on the physical machine, so long as adequate hardware resources (such as memory, CPU, and storage) are available for the virtual machine to use.
Like VMware ESXi, Hyper-V is able to run a variety of guest operating systems within virtual machines, and the two hypervisors share many similar core features. Whereas VMware’s ESXi is a complex environment with a steep learning curve however, Hyper-V tends to be more simplistic, and easier to use.
Microsoft originally introduced Hyper-V in Windows Server 2008, and it has been a part of each Windows Server release since that time. Each new Windows Server release has brought with it many new Hyper-V features.
Windows Server does not enable Hyper-V by default. Those wishing to host Hyper-V virtual machines on a Windows Server will need to install the server’s Hyper-V role. It is worth noting however, that this is not the only way to get Hyper-V. Microsoft also offers a free, standalone version of Hyper-V that can be installed without Windows Server. This free edition is simply known as Hyper-V Server.
Although Microsoft makes Hyper-V Server available for free, the operating systems and any other software running within the virtual machines must be properly licensed. In the case of Windows Server however, licensing works a bit differently.
The Windows Server license covers the host operating system and virtual machines that are running a Windows Server operating system. A Standard Edition license of Windows Server allows Windows Server to be run on up to two Hyper-V virtual machines (or Hyper-V containers). A Windows Server Datacenter license allows Windows Server to be run on an unlimited number of Hyper-V virtual machines on the host.
Hyper-V is also included with some Windows desktop operating systems, such as 64-bit editions of Windows 8 Pro and Windows 10 Pro. In the case of a supported Windows desktop OS, Hyper-V can be enabled through the Control Panel (it’s listed as a Windows feature). Microsoft commonly refers to Hyper-V running on a desktop operating system as Client Hyper-V.
Client Hyper-V is almost identical to Hyper-V Server and to the Hyper-V role running on Windows Server. There are a few enterprise class features that are missing from Client Hyper-V, but for the most part, client Hyper-V works similarly to server based Hyper-V deployments.
Regardless of which flavor of Hyper-V an organization may be using, the primary management tool is the Hyper-V Manager. The Hyper-V Manager is a GUI based management tool that is installed automatically when you install the Hyper-V role or enable client Hyper-V. It is worth noting however, that the Hyper-V Manager is not the only available interface for managing Hyper-V. Any management task that can be performed through Hyper-V Manager can also be performed through PowerShell.
Microsoft does offer one additional tool for managing Hyper-V. It’s called System Center Virtual Machine Manager. It is part of Microsoft System Center suite of management products and is licensed separately from Hyper-V.
The Hyper-V Manager tends to take a host centric approach to the management process. In other words, the interface is designed to allow you to see a Hyper-V host and the virtual machines that exist on that host. This approach is fine for smaller shops that only have a few Hyper-V hosts, but host centric management does not scale well for larger organizations with lots of Hyper-V hosts.
System Center Virtual Machine Manager (which is sometimes referred to as VMM), is equipped with an interface that is much more conducive to the bulk management of Hyper-V hosts and virtual machines. Additionally, VMM includes a number of enterprise class capabilities not found in Hyper-V Manager, such as bulk VM creation capabilities and the ability to create private clouds.
Regardless of which management tool is used, Hyper-V includes a variety of native features that are essential to running virtual machines in a production environment.
The Live Migration feature allows a running virtual machine to be moved to a different host without incurring any down time.
Hyper-V replica feature can be used for disaster recovery. It allows a standby (and synchronized) copy of a virtual machine to reside on a secondary host, ready for activation in the event of a problem with the primary VM copy. An extended replica feature allows for the creation of an additional virtual machine copy, which can reside offsite.
Another useful Hyper-V feature is its ability to create snapshots (which Microsoft calls checkpoints) of virtual machines. These checkpoints can be used to roll a virtual machine back to an earlier point in time without restoring a backup.
Overall, Hyper-V is an incredibly versatile hypervisor. It can run from a single Windows desktop, or it can operate at cloud scale, or anywhere in between. In fact, the Microsoft Azure cloud is based on Hyper-V.