Why You Should Use Virtual Machines

Virtualization have once been thought of as a technology only big businesses would incorporate in their environments. Now days however, smaller businesses and even home users are realizing the many benefits of using this great technology to help them not only lower costs, but also for security purposes as well. The good news is, while the underlying structure of virtualization is pretty complicated, you don’t necessarily have to be a rocket scientist to actually use it!

Alright so now you’re wondering, what in the world is all this virtualization and virtual machine technology and how can I start using it? Well, you can think of virtualization as a type of emulation. Basically you’re duplicating the functions of one system using a another system. Still confused? I’ll put it this way. It’s a system within another system. So for example with virtual machines, you’re installing a system within the one you are using right now. Huh? How can that be? Think of this as just another piece of software. You’re probably thinking that if you are to install another system, it has to be on another physical machine right? Not at all. This is where virtualization comes in. It virtualizes the physical components so to the piece of software, it actually ‘thinks’ that it’s being installed on another physical machine but in reality, it is being emulated on another actual physical machine. A system within a system. To further drive the point home, take a look at this picture and all should be understood.

If this is your first time seeing a virtual machine, you’re probably either shocked or confused. You have what seems like the Windows XP operating system in the background while you have at the foreground the Windows Vista operating system. A system ‘within‘ a system. These machines are referred to as the host and guest, with XP being the former and Vista being the latter. Once the idea starts to sink deeper into your head, you’ll begin to realize the potential this technology can offer.

The Advantage of Using Virtual Machines

One of the first benefits you should have realized is the potential energy saver virtualization can be. Without the need for an actual physical machine for every system you have, that’s one less system draining your energy resources which in turn brings down the energy bill. This might not be of concern to most home users but think about the smaller to mid sized companies who usually require a dozen or so servers being operational 24/7. By utilizing virtualization, they can consolidate those servers into just a few physical machines. Our planet is definitely in peril and many companies, both large and small have begun going ‘green’ in order to preserve our planet and one of the best ways of doing so is by reducing their electricity uses.
From a security standpoint, virtual machines are isolated from their host counterparts. However, the guest and host machine still share some type of hardware with each other. For example, your guest virtual machine can connect to the Internet through the actual network adapter of your host computer. The good news is that mess up’s from the virtual machine does not usually spill over or affect the host machine. In a way, they are isolated. So, if you your virtual machine crashed, your host machine will be unaffected and continue to operate as if nothing happened. This allows you to use virtual machines as software test-beds. Before installing a piece of software on your production machine, try it out in the virtual machine first. This way you can test it out or to see if there are any incompatibility problems without ruining your main machine.
If you are still on the fence with Linux, what’s a better way to try it out without creating a dual-booting machine than with virtual machines? Remember, everything is ‘virtual’ so you do not have to worry about partitioning your hard drive or creating a dual boot configuration machine. Simply download your Linux flavor and install it in a new virtual machine. Within minutes, you’ll have a full blown copy of Linux to play and test in. If something goes wrong or if you simply have no need for it again, delete the virtual machine! No damage done whatsoever to your host machine.

What about backwards compatibility? Not all applications behave nicely in Windows Vista or the new Windows 7 operating system and so creating a Windows XP virtual machine inside those OS will allow you the opportunity to install and use those older legacy applications. In fact if you will be using Windows 7 Professional or higher, you are automatically granted a free Windows XP virtual machine from Microsoft to use at your disposal.

Disadvantages with Virtual Machines

Virtual machines however, is not the medicine to cure all problems. With everything good, there is also the bad. First of all in order to install another operating system as a virtual machine on your host computer, it should be pretty beefy in terms of hardware. Remember, you are now running two (or more) operating systems at once, on one physical machine. Most of the computer resources will be shared although the good news is that you can specify (to a certain extent) how they will be shared. For example, you can specify how much RAM your guest machine will have. In my example, my laptop is a Lenovo R61 (awesome laptop by the way) with 2GB of RAM, 2.2GHZ Core 2 Duo processor, a Nvidia Quadro NVS 140M graphics card and 160GB of storage space. Not really a powerful system but it gets the job done. With Windows 7 as my host machine, I usually dedicate 512MB-1GB of RAM to each of my virtual machine creations and they run fairly well. Of course, I only have one running at any given time.

Virtual machines, at its core, is still emulation. It’s probably not a good idea to play some intense video games in a virtual machine environment as there is slim 3D support. However, do realize that companies such as VMware, Sun and Microsoft are working on it. With virtual machines, if the main host computer shuts down or malfunctions, then so does all of its guest machines. Also, creating a virtual machine means yet another system to maintain. You still need to install patches and updates because they could still be infected with viruses and spyware.

Using Virtual Machine Software

There are two free software I use to create my virtual machines. You have to remember that these software just ‘allows’ you to create the virtual machines. You actually still need to provide your own operating system disc in order to install it. For example, if you want to install Windows XP as a guest operating system in a Windows Vista host, you will need to have a Windows XP install disc on hand.

Microsoft Virtual PC

Microsoft Virtual PC (VPC) is a replacement for Virtual PC 2007 and is used for Windows XP Mode under Windows 7. It’s currently in beta but I’m sure it will have a standard release at or around the time Windows 7 ships in October. Once you have it installed, creating a virtual machine is really simple. You can either use a install CD or use an ISO file already downloaded to your computer, such is the case if you want to try Linux. Here is a basic run down of how to get started:

If you don’t currently have any operating systems to install, feel free to download and install the free Linux Ubuntu operating system. Once you have downloaded the ISO (image) file, you can then use it in creating your first virtual machine.

1. Install Virtual PC.

2. Open the Virtual Machines folder from the Start Menu.

3. Hit the Create a Virtual Machine button.

4. Type in a name for your virtual machine.

5. Specify the amount of RAM you want to dedicate to this virtual machine (this can be adjusted in the future as well) and whether or not you want the virtual machine to connect to your network.

6. Create a virtual hard disk and give it a name. If this is your first machine, choose to create a dynamically expanding hard disk. Hit the Create button.

7. Select the virtual machine in the folder and select the Settings button. Here, you are allowed to configure some basic settings for your virtual machine. Go over them to familiarize yourself with it. If you select on the DVD Drive option, you’ll see that it is configured to access your physical drive. If you are using a install disc, no change needs to be made. If you are instead using an ISO file on your computer, choose the option above it and browse for the ISO file.

8. Start your virtual machine by double clicking on it. At this time, it should access either your physical CD/DVD drive or open your ISO file to begin the installation process.
Here is a screenshot of my virtual machine running in VPC on top of Windows 7.

Sun’s VirtualBox

This is an awesome and freely available virtualiztion tool. You can download it from their website. They have recently released the big 3.0 update and with it comes a big host of changes. One big feature is the ability to use Direct 3D 8 and 9 as well as OpenGL 2.0 applications in the virtual machine! This means that it can render those graphic intensive applications right inside your virtual machine. I’m really excited as things will only get better for virtualization technology.
Once again, getting started is really easy.

1. Download and install VirtualBox.

2. Hit the New button to create a new virtual machine.

3. Click Next on the Welcome Wizard. Type in a name for your virtual machine. You should also select from the drop down menu the operating system you will be installing.

4. Select how much RAM you want to allocate to this virtual machine.

5. In the next Virtual Hard Disk menu, simply create a new hard disk as recommended. When you are more familiar with how virtual machines works, you can tweak this setting for advanced options. In the next wizard, you’ll get to select the hard drive type of your virtual machine. Read through both of the options. You’ll then be able to specify how big you want your virtual machine’s hard drive to be.

6. Once that is done, review the summary of your settings and go back if you need to readjust them. Once you have everything set, you will see your new virtual machine name in the main area. Similar to VPC, we have to now specify what we will be using to install our operating system. Select your virtual machine and hit the Settings button. Here, you can also go over the other settings for your virtual machine and make any changes if necessary.
Head into the CD/DVD-ROM section. Enable the Mount CD/DVD drive option. If you will be using a physical disc for your installation, then simply hit OK to exit out of the settings menu. If you will be using an ISO file, select the ISO Image File option and browse for the ISO file like we did in VPC.

7. Once we have that set, simply start your virtual machine by selecting it and hitting the Start button. The installation for whatever operating system you will be installing will begin.
Once that is finished, you’ll be presented with your completed virtual machine. In my case, I now have Puppy Linux installed.

As you have witnessed, creating virtual machines is dead simple with Microsoft VPC and Sun’s VirtualBox. You basically just go through a couple of wizards answering a couple of questions and you’re on your way to having a second operating system on your machine to play with. If you are studying for your MCSA or other computer certifications, building virtual machines for trial versions of the Windows Server operating systems is a easy way to gain hands on experience. If you do a lot of software testing either for your work or at home, installing them in virtual environments ensure that everything works properly before moving it to your production machines.
Computers are so powerful these days right out of the box. Some come in no less than 6GB of RAM! Running and powering virtual machines will not be a problem at all. Virtualization surely wasn’t possible or even feasible for home computer users in the past but all things change over time and once you begin utilizing virtual machines, you’ll begin to see all types of potential for it.