Virtualization Services - CompTIA A+ 220-1201 - 4.1

To be able to take advantage of virtualization, you need something that is going to manage the process of keeping all of these different systems running. This is the virtual machine manager, often referred to as the hypervisor. The hypervisor is the software that manages this entire interaction between the virtual world and the physical system it's running on.

Hypervisors can run on almost any system, but many modern hypervisors can take advantage of CPUs that have specifically been built with virtualization in mind. And once this hypervisor is running, it can allocate CPU cycles, memory, networking information, and keep all of that separated between all of the different virtual machines. To understand more about how all of

these different operating systems interact with the hypervisor, I've created this block diagram that starts at the very bottom with the hardware. This is the physical system that the hypervisor is running on. On top of that hardware is the hypervisor and above the hypervisor are all of the different virtual machines. You'll notice that

each virtual machine has its own guest operating system and applications running within that OS. Since each one of these virtual machines has its own guest operating system installed and running, there is a significant amount of overhead that takes place every time you start a new VM. This means you'll need enough CPU cycles, enough memory,

enough drive space for all of these VMs to operate simultaneously on the same physical piece of hardware. This type of hypervisor that sits right on top of the hardware is known as a type one hypervisor. You might also hear this referred to as a bare metal hypervisor. That's because there's no operating system down at the lowest level. The