Updated April 18, 2018
Go from curious to well-versed by learning what you need to know about Kernel-based Virtual Machine / KVM technology and how it functions as a layer between the server hardware and operating system plus applications, a hypervisor process. Want to know the facts on what is KVM? Read on!
Virtualization – the idea of making server hardware appear to be wholly tied to a single operating system install, when in reality there are multiple instances running, simultaneously sharing the hardware.
Hypervisor – a process, or software layer, that gets inserted in between hardware and O/S, plus apps, that is the core of virtualization technology, enabling multiple installs to virtually share server hardware.
Kernel-based Virtual Machine / KVM – is a specific hypervisor for Linux on x86 hardware.
Virtualization Extensions – Intel VT or AMD-V, enable virtualization of hardware through kvm.ko (a loadable kernel module) – it makes hardware able to handle multiple virtual machines running on it simultaneously.
There’s more than one type of hypervisor. Some run at the lowest levels, directly on top of the hardware.
KVM is a type-2 hypervisor, which means it gets installed on top of the linux operating system, which runs on top of the hardware – a 2nd level.
KVM has been around for over a decade, having been built on the concepts and technologies from several decades of virtualization, such as blade servers, mini’s and mainframes.
When a server has KVM loaded, it can share resources among many virtual machines. Even though the host O/S is linux, KVM can handle both linux and Windows images. KnownHost specializes in linux installs. KnownHost – Fast, Optimised and Secure Shared Cloud Hosting.
Once the KVM hypervisor is in place, it takes one, or more, physical processors, video cards, storage drives and network cards and then creates multiple virtual devices to be uniquely allocated so each virtual machine gets their own virtual devices.
KVM on Linux
One of the key aspects of KVM is that it is open source. That means it’s free, as in free beer kind of free. Its kernel modules have been included in linux since 2.6.20.
You’d be hard pressed to find a flavor of linux that isn’t compatible with the KVM hypervisor.
KVM has competitors, such as VMWare ESXi and Microsoft Hyper-V, and performs as their equal, despite not having the same amount of notoriety.
More Than Pure Virtualization
KVM provides the virtualization capabilities, managing virtual machine memory, I/O, and other resources, but by default doesn’t include a friendly user interface. For that, you need tools, or addons. In this case, a virtual machine manager / VMM could provide the desired handy functionality.
VMM’s are one way to go, but there are entire administrative portals that provide this, and oh so much more, such as oVirt. https://www.ovirt.org/
KVM is a mature, stable technology that performs incredibly well when it comes to server virtualization.
KnownHost proudly offers KVM Cloud Server hosting solutions at a range of price points, all with incredible specifications, performance, support and management.