What does Type I virtualization replace on a physical server?

Type I virtualization, also known as bare-metal virtualization, operates directly on the physical hardware of a server. In this architecture, the hypervisor is installed directly on the physical server, allowing it to manage and allocate resources to multiple virtual machines.

When you implement Type I virtualization, the physical operating system typically running on the server is replaced by the hypervisor. This is a crucial function because it enables the hypervisor to efficiently utilize the server's hardware resources to create and manage virtual machines, thus enhancing performance, scalability, and resource management compared to traditional operating systems.

In contrast, a hypervisor, whether type I or type II, is simply the virtualization layer that enables multiple operating systems to run on the same hardware. Virtual machines are the instances created by the hypervisor, representing separate operating systems and applications running in isolated environments. Containers, on the other hand, are a form of application virtualization that allows applications to run in lightweight, isolated environments but do not replace the OS on the physical server in the same way.