Virtualization: When you need different operating systems running concurrently

Have you ever wished to run a particular program but got constrained by the version of Operating System (OS) on your machine? Well, my guess is that you could have been running either of Windows 7 or Vista.  While these two are the latest Operating Systems Microsoft has to offer, applications (or programs) that were built for earlier versions of windows tend to be operating system limited, and may not function properly if installed on machines running newer OS versions.

The good news, however, is that you could still have both OS’s running on your machine, either by way of virtualization, or having a dual boot machine-when you have both OS’s installed on the same computer.  Virtualization basically refers to the abstraction of computer resources, the simplest definition of which basically refers to the software implementation of a machine (computer) that executes programs like a real machine.

There are several forms of virtualization, some of which include:

Virtual machine: - Software which if installed on a machine enables the user to execute applications as if they were using a real machine. There are several types of virtual machine software; and these include Virtual PC and VMware (mainly for Microsoft Windows) while Virtual sphere is mainly used for Linux/Unix installations.

Application virtualization: - The hosting of individual applications on alien hardware/software;

This allows uniform, contiguous addressing of physically separate and non-contiguous memory and disk areas. Others include storage, desktop and network- creation of a virtualized network addressing space within or across network subnets virtualization among others. My main interest today is on the use of virtual machine software, an application that is increasingly becoming popular with most professionals, especially for use on different applications that vary in OS specification requirements.

Comparisons between the two options (dual boot and virtualization) bring a few points to the fore;

• Under a dual boot environment, the user will be required to restart the computer before they can access the second operating system. Virtualization, on the other hand will not require a reboot before one can access the second OS. All it takes is a proper installation of virtual machine software on the computer that is to be used.
• Under a dual boot set up, the OS in use will be able to access and utilize all available memory (read RAM), while with virtualization all available RAM will be shared between different running applications. This, however, should not be much of a concern if the machine in question has enough available RAM.

So Which Option is better?

On the whole, using virtualization seems a much more convenient option since the software-once installed-can be started anytime without the user having to reboot the computer. It is a direct switch to and fro application that will also allow a user on the virtual machine to access-among others-network resources, as well as having the added advantage of allowing the user to interact with the same machine on which the virtual machine itself is configured.

A virtual machine also has the advantage of being transferrable-once properly configured on a machine, its settings may be transferred to another workstation/machine and still functions as good as it was before. Simply put, it is a pc that is simply operating from another PC (the host). On the other hand, if you are the kind of person that likes your available resources maximally utilized, dual boot option should be your choice.

- Dan B. Atuhaire