isäntähypervisoris

An isäntähypervisoris, or host hypervisor, is a fundamental component of virtualization technology. It is software, firmware, or hardware that creates and runs virtual machines (VMs) on a physical computer, known as the host. The host hypervisor's primary role is to manage the host system's resources, such as CPU, memory, storage, and network, and allocate them efficiently among the various VMs it hosts.

There are two main types of host hypervisors. Type 1, also known as bare-metal hypervisors, run directly on the host's hardware without an underlying operating system. Examples include VMware ESXi, Microsoft Hyper-V (when installed as a standalone role), and Xen. This direct access allows for greater performance and security as there is no intervening operating system layer. Type 2, or hosted hypervisors, run as an application on top of a conventional operating system, like Windows, macOS, or Linux. Examples include VMware Workstation, Oracle VirtualBox, and Parallels Desktop. While easier to set up and use for desktop virtualization, they generally offer slightly lower performance due to the overhead of the host operating system.

The host hypervisor provides an abstraction layer, allowing multiple operating systems and their applications to run concurrently and in isolation on a single physical machine. Each VM believes it has dedicated hardware, but in reality, the hypervisor is orchestrating access and preventing interference between them. This isolation is crucial for security and stability, ensuring that a crash or issue in one VM does not affect others or the host system. Host hypervisors are key enablers of cloud computing, server consolidation, testing environments, and disaster recovery solutions.