Hypervisors

Hypervisors

CIS512: Enterprise Architecture

A hypervisor, also known as a virtual machine manager/monitor (VMM), is computer hardware platform virtualization software that allows several operating systems to share a single hardware host. Each operating system appears to have the host’s processor, memory, and resources to itself. Instead, the hypervisor is controlling the host processor and resources, distributing what is needed to each operating system in turn and ensuring that the guest operating systems/virtual machines are unable to disrupt each other. In virtualization technology, hypervisor is a software program that manages multiple operating systems, or multiple instances of the same operating system, on a single computer system. The hypervisor manages the system's processor, memory, and other resources to allocate what each operating system requires. Hypervisors are designed for particular processor architecture and may also be called virtualization managers.

Hypervisors are classified into two types: Bare Metal/Native Hypervisors— Software systems that run directly on the host’s software as a hardware control and guest operating system monitor. A guest operating system thus runs on another level above the hypervisor. This is the classic implementation of virtual machine architectures. It is a virtualization layer that is installed above a host operating system (OS), such as Windows Server, Linux, or a custom OS installation.  The host operating system has direct access to the server's hardware and is responsible for managing basic OS services.  The Type 2 Hypervisor creates virtual machine environments and coordinates calls for CPU, memory, disk, network, and other resources through the host OS. Embedded/Host Hypervisors is software applications that run within a conventional operating system environment. Considering the hypervisor layer being a distinct software layer, guest operating systems thus run at the third level above the hardware....