Type 1 vs Type 2 Hypervisors: What's the Difference?

A hypervisor is the software that creates and runs virtual machines. It lets one computer run multiple operating systems at the same time, each inside its own VM, while they share the same physical hardware.

The hypervisor divides hardware resources — CPU time, memory, storage and network access — between VMs and keeps each guest operating system isolated from the others. How it does that, and what sits between it and the hardware, is what separates the two types. For the broader picture, see what server virtualization is.

A Type 1 hypervisor is installed directly on the physical server, without a general-purpose operating system underneath. It controls the hardware itself and schedules VMs onto it. This is why Type 1 hypervisors are also called bare-metal hypervisors.

Type 1 hypervisors are the standard choice for enterprise server virtualization. They are designed for continuous operation, clustering, high availability and remote management, and they are typically managed centrally rather than from a local screen.

A Type 2 hypervisor — also called a hosted hypervisor — runs as an application on top of an existing operating system such as Windows, macOS or a Linux desktop. The host OS manages the hardware, and the hypervisor requests resources from it.

Type 2 hypervisors are convenient for individual use. Common scenarios include:

The comparison below reflects typical designs; individual products vary.

It is tempting to say Type 1 is always faster, but real performance depends on hardware support, drivers, storage, configuration and workload. Hardware-assisted virtualization has narrowed many historical gaps.

"Bare metal" simply means the hypervisor is the first software layer on the hardware. Because it is not competing with a desktop operating system, it can dedicate the machine to running VMs, reduce the attack surface and be managed as infrastructure.

Bare-metal hypervisors form the base of most data center and private cloud designs, where many hosts are clustered and managed together.

KVM is built into the Linux kernel. When enabled, the Linux kernel running directly on the server acts as the hypervisor, and VMs use the processor's virtualization extensions. From that perspective KVM behaves like a bare-metal, Type 1-style hypervisor and is used that way in enterprise and cloud environments.

At the same time, the host is a full Linux system and each VM runs as a Linux process, which is closer to how Type 2 hypervisors are often described. The simplified historical model does not map perfectly to this design, and that is fine — the classification matters less than capabilities such as performance, isolation, hardware support and management. Our guide to the KVM hypervisor explains the architecture in more depth.

Hypervisors are central to server virtualization, but the word "virtualization" covers several distinct concepts:

These are different technologies with different tools. VirtuWa focuses on server virtualization and private cloud infrastructure; it does not provide desktop or application virtualization products.

For production server workloads, the hypervisor type is only the starting point. Evaluate the complete platform around it:

Asas HV is VirtuWa's server virtualization foundation, built on KVM, QEMU and libvirt and deployed directly on server hardware. Together with centralized management, migration, backup/DR and automation across the VirtuWa platform, it is designed for production data center and private cloud workloads. To see how virtualization grows into a managed service, read virtualization vs private cloud.