Server virtualization is cool. VDI is not. Desktop virtualization is hot.
Not everyone has a server-class system lying around waiting for conversion to a virtual server host and furthermore, you don’t really need one. If you run Linux but need a Windows system or run Windows but like Linux, you can have both with desktop virtualization. Desktop virtualization is where it all began with the original release of VMware in early 1999. Our own Jason Perlow did a review of it for the â€œOn the Desktop” column when it first came out. With VMware Server, VMware ESX/ESXi, and XenServer, why would you want or need a desktop virtualization product at all? That’s an easy one: Resources.
For Microsoft fans, there’s Microsoft’s Virtual PC. For those of you who like to ride both sides of the fence, there’s Sun’s xVM VirtualBox, VMware’s desktop products, and Parallels Workstation. For those of you who are really naughty, Parallels and xVM VirtualBox also run on the Mac. I’m trying to eat lunch (and keep it down) while writing this so I can’t discuss anything Mac.
This four-part series on Desktop Virtualization explores each of these related but different approaches to the same problem: Running two different operating systems simultaneously on the same hardware.
Due to licensing issues with installing Windows guests, I’m using a Windows computer (Windows XP) as the host with Linux guests. I’ve selected Debian 5.0 running XFCE for the standard Linux guest VM.
Sun’s xVM VirtualBox software is a good place to start for this series. It’s multi-platform (Windows, Mac, Linuxâ€”but not Solaris), it’s free, it’s very easy to use, and it’s very small (~59MB Installed). The installer file is a mere 37MB and downloads very quickly. Windows installation is fast, simple, and complete with only a few clicksâ€”no advanced knowledge of virtualization required.
Setup a New VM
Once installed, xVM VirtualBox is ready to host a VM. My choices are in parentheses. To setup a new VM, click New->Name your VM (For example, Debian5), select the Operating System (Linux), and Version (Debian). Click Next. Set the VM Memory (256MB). Click Next. The Virtual Hard Disk prompts you to create a new virtual hard disk or select an existing one. Since this is a new installation, select New and the Virtual Disk Wizard steps you through creating one. Click Next. Choose Fixed size for better performance. Click Next. Select a virtual disk size and location. Choose a size for your diskâ€”8GB is the default (2 GB). Click Next and Finish. You’re returned to the Virtual Hard Disk Screen. Click Next. Select your Disk from the dropdown menu. Click Finish. Figure 1 shows you the new VM (Debian5) and its configurable components.
Figure 1: Fresh VM and its Configurable Components
You’ll notice from Figure 1 that the CD/DVD-ROM drive isn’t mounted. Before you’re able to install a new operating system into the VM you’ve just created, you have to specify an installation source (CD/DVD or ISO). To do this, click CD/DVD-ROM in the righ pane, Select Mount CD/DVD Drive, and then select the physical CD/DVD Drive that contains a bootable operating system image or select ISO Image File. Browse to and select your ISO image by clicking the Browse icon, remove VMAdditions.iso, click the Add button, find your ISO image, click the Select button, and click OK to return to the main xVM screen.
Install the Operating System
You’re now ready to power on the VM and start the installation. Click Start to power on the new virtual machine. A console screen appears in a separate window and the installation begins. If you need to release your mouse and keyboard focus from the VM’s console screen at any time during the installation, press the Right Ctrl key on your keyboard. Clicking inside the console will return focus to the console. The installation proceeds with or without mouse and keyboard focus. Page through your installation until it’s complete. I used all default values for this demo VM installation.
Enjoy Your New Virtual Machine
The new virtual machine is fully functional and ready to serve. This VM is just like any guest VM on a virtual server host system. Install or remove software, setup Internet services, write an OpenOffice.org document, play a game, or open a browser and surf the Internet.
To customize your system’s hardware, you’ll have to shut it down just as you would a physical computer. Please note that by default your new VM’s network setup uses NAT, which means that it uses your host computer’s network adapter to connect to outside resources (Internet, Software Repositories, Other Systems) but those connections look as if they originate from your host and not the VM. If you want to SSH to your VM from the host or other remote computer, shut down the VM, click the Network link in xVM’s right pane, use the dropdown selection, Attached to:, and select Host Interface. Click OK and start the VM. The VM automatically obtains an available IP Address from your DHCP server (For example, your router).
Despite some of xVM’s shortcomings, I like it. If you’re looking for a desktop-level virtualization solution that’s easy to use, quick to install, and priced right; xVM is definitely worth a try. Don’t expect it to be an enterprise-level solution or a replacement for something more robust, like VMware’s Workstation product, but for the money, you’d be hard-pressed to find something better.
Kenneth Hess is a Linux evangelist and freelance technical writer on a variety of open source topics including Linux, SQL, databases, and web services. Ken can be reached via his website at http://www.kenhess.com
. Practical Virtualization Solutions by Kenneth Hess and Amy Newman is available now.