I used to think that the best first step to explore Linux was through a live Linux CD. A live Linux CD is a bootable CD that contains a complete Linux installation compressed onto a CD. The KNOPPIX Linux Live CD, is perhaps one of the first and most popular examples of a bootable Linux CD. In order to boot this version of Linux, all you would have to do is first, make sure that your computer is configured to boot from the CD-ROM. Most modern IBM-compatible PC's come already configured to boot from the CD-ROM. If not, you would have to modify your BIOS configuration to include boot from CD-ROM as the first option in the boot order. The only other consideration to boot the CD was whether your PC met the minimum hardware requirements.The two most important hardware components are the video graphics card and the amount of random access memory (RAM). From most people, they meet the minimum requirements and then some, because the live Linux CD is optimized to run on the most meager of systems.

This was a great option because it would allow a new Linux user the flexibility to try Linux without having to install any software. And even though you wouldn't have to install any software, you received almost all of the functionality of a full-blown Linux installation; even down to hardware detection and automatic configuration. This would mean that following a successful boot of the CD, you would have access to networking, the most popular open-source applications, and USB-devices. In addition, you would typically have read-only access to NTFS Windows partitions and complete read/write access to FAT or FAT32 formated Windows partitions. The latter feature made live Linux CDs a favorite for system administration technicians, because it allowed them to fix potential Windows boot problems while using the live Linux CD. The biggest disadvantage in using the live Linux CD was unresponsiveness. Since the operating system resides on the CD, you are often reading information from the CD. This causes the system to be slower than usual. This slowness was most painful when booting the live Linux CD; often requiring many minutes before the system would finish booting and become usable. A final disadvantage is that you'll not be able to save much in the way of operating system configuration and customization. While you can use a USB to save files and some configuration information, for the most part you'll lose everything between different boots of the CD.

Over the course of the last year, my advice evolved. Now through the wonders of virtualization, a new Linux user could boot a live Linux CD without having to actually reboot your machine. Virtualization provides the ability to create a virtual machine within your existing operating system installation. A virtual machine is a computer defined in software. Through this technology you can install Linux within your existing Windows machine. While there are many alternatives available, a subset of the choices includes Microsoft Virtual PC 2004, the Open Source Virtual Machine with Hypervisor OpenVZ, the open-source Xen, and the free QEMU, my favorite is from VMWare, Inc. With both free offerings and more feature complete enhanced products, VMWare has been very successful producing easy to use products that meet the needs of the virtual machine marketplace. While the VMWare Workstation can actually create virtual appliances (virtual machines), I've been using the VMWare Player, so I'll dive into more detail about what you can do with the Player.

This simple diagram from the VMWare website illustrates the relationship between the actual computer and the virtual machines (virtual appliances in the VMWare world). As you can see the software computer residing within a computer very accurately describes the virtualization technology.

As I mentioned, this advice has evolved as I have learned more about the technology. This first mutation, involved booting live Linux CDs within a virtual machine. With the VMWare Player you can use an image of a live Linux CD and the live Linux CD virtual appliance to accomplish the same Linux booting as described before. A live Linux CD image is the copy ( a file) of the live Linux CD that you would use to create a bootable CD by copying the image onto a blank CD. To complete the process of booting a live Linux CD within the VMWare Player, involves:

• downloading and installing the VMPlayer;
• downloading your live Linux CD of choice, I recommend the live Linux CD list over at Distrowatch.com;
• and then downloading and extracting the LiveCD Player virtual appliance and following the instructions as listed on the VMWarez web page.

Now with this configuration you can download and test as many different Linux distributions until you find the one that suits you most. By running off of the hard disk, using virtualization, solves some of the latency problems you will observe booting the live Linux CDs from CD. However, it still doesn't solve your inability to tweak and customize your Linux virtual machine; and how boring would that be?

As I have been playing around with the VMWare Player, VMWare and a broad group of Linux distributions have been building a collection of virtual appliances. Through the participation of the community and VMWare partners, you can now download a wide variety of pre-configured virtual appliances from some of the most popular Linux distributions. As of this blog post you can download and use virtual appliances from

• Debian
• Fedora Core
• FreeBSD
• SUSE or SLES
• and Kubuntu or Ubuntu.

There are even more available, and I know that the list will continue to grow. Assuming that you already have the VMWare Player installed, all you have to do to run these virtual appliances is download, extract (if necessary), and boot.

Booting one of these virtual appliances gives you a completely customizable Linux machine while enjoying the convenience of still running your host operating system. You can add or delete applications by using online software repositories and even custom your desktop. In conclusion, this final mutation is the best way for a new Linux user to get started with Linux. With only a small investment in hard disk space and time, you'll get as close to a full Linux experience without having to reformat your hard drive and install Linux. It solves all of the disadvantages of booting a live Linux CD and brings some incredible advantages. First, the VMWare Player has the ability to suspend your Linux virtual machine automatically. Make sure that the Player is configured to suspend on Exit, select Player->Preferences and ensure the "Suspend the virtual mahince" option is selected under the "When exiting" option. With this you'll be able to merely exit Linux and pick up almost immediately from where you left off. This eliminates any waiting for Linux to boot within the virtual machine. Second, you can create a "backup" copy of your virtual machine. While not using your virtual appliance, simply copy the directory that contains your appliance to another directory. If, for whatever reason, you want to "start-over", simply copy the back-up into a new directory and you're back in business with a fresh install of your virtual machine. This configuration provides maximum flexibility, is extremely easy to implement and use, and provides a rich and full Linux experience. If you've been waiting for an easy way to try Linux, virtualization and pre-configured virtual machines eliminate nearly all of the obstacles. Go ahead and get started, it couldn't be easier!