How to understand virtualization environments.

How To Understand Virtualization Environments.

Server virtualization is the process of dividing a physical server (computer) into multiple unique and isolated virtual machines (VMs) by means of a software application. To put it simply, this is a box with various storage sections. 

A server divided into VMs is called a host machine (the box), and the VMs are called guest machines (the sections). 

The whole process is controlled by a hypervisor.  

What is a virtual machine?

When virtualization segments a physical machine, each virtualization instance is a virtual machine (VM). A VM operates as if it were its own computer with its own specified allotment of processing power, memory, and storage available on the physical hardware.

Each VM runs its own operating system and applications independent of the other VMs. To coordinate multiple virtual instances without interference, VMs rely on a piece of software called a hypervisor to interact with the underlying hardware.

Reasons To Use Server Virtualization

  • Save money.

  • Reasons To Use Server Virtualization

  • To isolate users, their actions and data

  • Not to have downtime

  • To evenly spread the load between several servers

Hypervisors are an essential part of the technology supporting cloud computing. There are two types of hypervisors — bare-metal and hosted, and numerous solutions in the market. In this post we are going to cover both types, including a list of well-known hypervisors — both commercial and open-source. But let’s start by defining what a hypervisor is.

Types of Hypervisors

Type 1 hypervisor— a bare-metal or software hypervisor (Xen, KVM, ESXi)

There is only one layer between a VM and server hardware — a hypervisor.

  • Open source bare-metal hypervisors: KVM, Proxmox and Xen.

  • Commercial bare-metal hypervisors: Red Hat Enterprise Virtualization (RHEV), Citrix XenServer, Hyper-V and VMware ESXi.

  • Security – The type 1 hypervisor has direct access to hardware without an additional OS layer. This direct connection significantly decreases the attack surface for potential malicious actors.

Type 2 hypervisor— a hosted hypervisor (VMware Workstation, OpenVZ)

There are two layers between a VM and server hardware — an operating system and a hypervisor.

  • Open source hosted hypervisors: QEMU and VirtualBox.

  • Commercial hosted hypervisors: Parallels Desktop, VMware Workstation Player and VMware Fusion.

There is also the third type, a hybrid one, but it’s a subject of big debate, so I won’t load you up with useless information.  

Type 1 vs. Type 2 Hypervisor: Choosing the Right One

Choosing the right type of hypervisor strictly depends on your individual needs.

The first thing you need to keep in mind is the size of the virtual environment you intend to run.

  • For personal use and smaller deployments, you can go for one of the type 2 hypervisors. If budget is not an issue, VMware will provide every feature you need. Otherwise, Oracle VM VirtualBox is a hypervisor that will provide most of the required functionalities.

  • For enterprise environments, even though type 1 hypervisors are the way to go, you need to consider many factors before making a decision.


This article has explained what a hypervisor is and the types of hypervisors (type 1 and type 2) you can use. Hypervisor vendors offer packages that contain multiple products with different licensing agreements. You will need to research the options thoroughly before making a final decision.

If it’s hard for you to decide, Nexonhost specialists are available 24/7.