What is virtuilization?

Posted on Fri 19 August 2016 in Virtualization

What the hell is virtualization, why should I care and how can I use it?

There's a joke: "Try explaining virtualization to your grandma"

Virtualization, or virtual infrastructures are accepted, as a basic requirement in the work place. Many know how to successfully implement and maintain it, few, including myself, can explain it in simple terms. I'll give it a bash:

Virtual computers are computers within computers. Multiple operating systems running within one "master OS". One server, a hypervisor, acts as an interpreter between the application, OS and hardware layers. You are able to install several operating systems in one chassis and run them all at the same time.

An operating system needs to be able to speak with the hardware of the computer;

(user moves mouse left)
• OS - Hardware
• tell the USB BUS to move the USB device01 left
• hardware-hardware
• tell the display bus 
• print the action to screen 
(mouse movement)

In very simplistic terms, that’s how an operating system would usually interface with the physical hardware. With virtualization, an extra layer is added to the communication. The hypervisor interprets the operating systems request, relays it to the hardware, who in turn, relays back to the hypervisor then up to the OS.

This means that the hypervisor is able to relay messages from many operating systems, as opposed to direct OS-hardware communication. In essence, the hypervisor is the operating system, the operating systems are applications.

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Virtualizing a server infrastructure has many benefits:

• server consolidation
• decrease running costs
• decrease space needs 
• decrease server deployment costs 
• increase maintenance efficiency

For home, ditto the above:

• learning opportunity's
• testing environment
• home automation
• good fun

Hypervisor OS's are generally free for the basic versions. Older equipment can be re-utilised to create a virtual environment I have one hypervisor that serves up two file servers, a Windows domain environment, with workstations, a media server, virtual desktop and several other test Linux and Windows guests, all contained in one PC chassis. Often, what I'm doing at home is being replicated at work. It's good fun to be able to learn and test at home then work in production environments with added confidence.

If you have old kit lying about, hack it together and spin up a few virtual machines!