“Virtualisation technology allows multiple virtual machines
to run different operating systems, such as Windows, Linux and UNIX on a single
computer. Each virtual machine has its own set of virtual hardware resources
(e.g., CPU, RAM, Hard Drive, etc.) allowing the operating system to run as if
it were installed on a physical machine.” (CIO.com)
The simplest way to define virtualisation is that it implies
the disassociation of software from any form of specific hardware (i.e. server).
As such, software applications or data are no longer tied to specific machine.
What makes virtualisation so attractive to enterprises and
IT departments is the potential cost saving factors. So let’s first have a look at some of these benefits.
- Virtualising your servers prepares your enterprise for the cloud. First, you would move from a basic virtualised data centre to a private cloud and eventually move into a cloud hosting environment.
- Consolidation of servers to virtual servers leads to fewer physical serves resulting in lower cooling and power costs in the data centre.
- Fuller utilisation of fewer physical servers. This also means fewer machines and fewer numbers of racks leading to less data centre floor space requirements.
- Removal of the dependency on particular hardware and of being locked into particular vendors because server virtualisation subtracts away the physical hardware and replaces it with virtual hardware.
- Ability to easily move virtual machines between servers when a legacy server needs to be deactivated or removed for servicing.
Virtualisation is currently making head roads in 3 areas of
IT, in particular, Network Virtualisation,
Storage Virtualisation and Server Virtualisation. What we touched on above relates mainly to Server Virtualisation and we will
discuss the other areas in future posts.
However, if you are interested in the topic of virtualisation
and looking for a bit of direction, here are a few areas to venture into.
- Hypervisor is the software that bridges the physical hardware with the operating system and applications.
- Virtual Machine (VM) is the self-contained operating environment.
- Virtual Appliance (VA) is a pre-built and configured application in the operating system inside a VM.
- Xen is a free, open-source hypervisor for x86 (a family of instruction set architectures based on the Intel 8086).
