developerWorks: Discover the Linux Kernel Virtual Machine

Linux® and flexibility go hand in hand, and the options for virtualization are no different. But recently, a change in the Linux virtualization landscape has appeared with the introduction of the Kernel virtual Machine, or KVM. KVM is the first virtualization solution to be part of the mainline Linux kernel (V2.6.20). KVM supports the virtualization of Linux guest operating systems — even Windows® with hardware that is virtualization-aware. Learn about the architecture of the Linux KVM as well as why its tight integration with the kernel may change the way you use Linux.Virtualization is a concept that has been around for quite some time. Succinctly, it’s the process of taking something and making it look like something else. Applying this concept to a computer system allows different users to view that single system differently (for example, a single computer that runs both Linux and Microsoft® Windows® concurrently). This is commonly called full virtualization.

KVM and kvm
In this article, I refer to KVM when talking about the Kernel Virtual Machine and kvm when discussing the hypervisor utility (used to kick off a new virtual machine).

Virtualization can also take a more complicated form, where a single computer appears as multiple architectures (to one user, it’s a standard x86 platform; to another, it’s an IBM Power PC® platform). This form of virtualization is commonly known as hardware emulation.

Finally, a simpler form of virtualization is operating system virtualization, in which a single computer runs numerous operating systems of the same type. This type of virtualization simply isolates several servers on a single operating system (which means that all must use the same type and version of the operating system).

Complete Article