Some concepts in virtualization

Posted by Aruna Lakmal on 6:39:00 PM with No comments

Some concepts in virtualization

Virtualization is building a virtual version of an actual entity. Basically when it comes to IT, building a software based virtual entity instead of actual entity normally we call as “Virtualize” the physical environment.
As an example we can say that creating a Virtual Machine virtualize the physical hardware level computer, this Virtual Machine (VM) act like a real computer with an operating system.
In Hardware level virtualization, the base PC or Server also known as “Host” is the actual hardware level computer which delivers the virtualization and the VM which we build on the Host is known as the “Guest”.
The software which creates an environment to deliver the virtualization is known as “Hypervisor”.

There are basically three types of Hardware Level virtualization concepts:

           Full Virtualization – Complete Virtualized version of the actual hardware
           Partial Virtualization – Virtualize some part of the actual hardware but not all.
           Paravirtualization– The complete hardware level computer is not simulated, some modifications need to be done from the virtual environment

Software-Defined Datacenter:is the foundation of the Cloud Computing. It creates the virtual version of the actual datacenter with isolated computing, storage, networking and the security resources faster than the actual Hardware level datacenter.

I would like to compare the Advantages of the Virtual Machines and the Physical Hardware level machines.

Physical MachineVirtual machine
Difficult to relocate the Physical HardwareEasy to relocate: VM consists of set of files, Some “cluster features” can be used to relocate the VM. (VMotion)
Dependent of Physical Hardware Independent of Physical Hardware
Difficult to maintain the physical machine needs some down timeEasy maintenance without a downtime: If a host needs a downtime we can use some cluster features to avoid the impact of the downtime.(VMotion)
Limited Hardware resource in a single MachineHardware limitation can be avoided
Servers are Physically individual Allows servers to be consolidated and run several VMs in single host.