The type of software that controls the host processor and resources, allocates necessary resources to virtual machines (VMs), and prevents VMs from disrupting each other is called a hypervisor. A hypervisor acts as an intermediary layer between the physical hardware and the virtual machines running on top of it. It creates and manages multiple VMs on a single physical host by abstracting the underlying hardware. The hypervisor dynamically allocates CPU, memory, storage, and network resources to each VM according to its needs while ensuring isolation and fault tolerance so that one VM cannot interfere with another
. There are two main types of hypervisors:
- Type 1 (Bare-metal) hypervisors run directly on the host's hardware and manage guest operating systems. Examples include VMware vSphere/ESXi, Microsoft Hyper-V, and Citrix Hypervisor
- Type 2 (Hosted) hypervisors run on top of a host operating system and manage guest VMs within that OS environment.
Popular virtualization software platforms that function as hypervisors include VMware vSphere, Microsoft Hyper-V, KVM, oVirt, Red Hat OpenShift Virtualization, and Citrix Hypervisor
. These platforms provide advanced resource management, isolation, and control features to efficiently run multiple virtual servers on a single physical machine. In summary, hypervisor software is responsible for controlling host processors and resources, allocating resources to virtual machines, and isolating VMs to prevent interference among them
