2.2 Virtualization

Question 1

HYPERVISOR

Answer 1

The hypervisor is a program, firmware, or hardware that adds an abstraction layer on top of the physical hardware.
The abstraction layer is used to create virtual machines which have access to all the hardware of the physical machine such as CPUs, memory, disk controllers, and NICs.
Each of these virtual machines runs a complete and separate operating system.

Question 2

Type 1 Hypervisor

Answer 2

Type 1 hypervisors are also called the “bare metal” approach because the hypervisor is installed directly on the hardware.
Type 1 hypervisors are usually used on enterprise servers and data center networking devices.

With Type 1 hypervisors, the hypervisor is installed directly on the server or networking hardware.
Then, instances of an OS are installed on the hypervisor.
Type 1 hypervisors have direct access to the hardware resources; therefore, they are more efficient than hosted architectures.

Question 3

Type 2 Hypervisors

Answer 3

A Type 2 hypervisor is software that creates and runs VM instances.
The computer, on which a hypervisor is supporting one or more VMs, is a host machine.
Type 2 hypervisors are also called hosted hypervisors.
This is because the hypervisor is installed on top of the existing OS, such as macOS, Windows, or Linux. Then, one or more additional OS instances are installed on top of the hypervisor.
A big advantage of Type 2 hypervisors is that management console software is not required.