Virtualization Essentials

Understanding How a Virtual Machine Works

One way to look at how virtualization works is to say that a hypervisor allows the decoupling of traditional operating systems from the hardware. The hypervisor becomes the transporter and regulator of resources to and from the virtual guests it supports. It achieves this capability by fooling the guest operating system into believing that the hypervisor is actually the hardware. In order to understand how the virtual machine works, you need to look more closely at how virtualization works.

Without going too far under the covers, let’s examine how a native operating system manages hardware. Figure 3.9 will help illustrate this process. When a program needs some data from a file on a disk, it makes a request ...