San Francisco - Today's IT managers face tough choices. PCs that run fine today have an uncertain upgrade path, now that . Upgrade costs associated with Vista, coupled with the ever-escalating cost of application licenses, make switching to desktop Linux an increasingly attractive option.

For many businesses, however, it's difficult to know where to begin. The Linux market is broad and thriving, with myriad options to choose from. Most organizations will want to phase in Linux gradually, which in many cases will mean supporting a heterogeneous computing environment for the first time. As a result, it can be hard to predict where software incompatibilities might affect critical business processes.

[ IfVista has you looking to make the Linux switch, be sure to also check out and ]

Fortunately, the future of Linux on the business desktop has never been brighter. Bolstered by contributions from some of the , today's Linux offers a rich, highly functional user experience to compete with any proprietary OS. With appropriate planning, integrating a limited number of Linux desktops into your existing environment can be undertaken with minimal difficulty, paving the way for a broader migration tomorrow.

Finding the right match for your business
If you do deploy Linux, choosing a distribution is one of the most important decisions you will make. Don't be tempted to mix distributions haphazardly. Each flavor of Linux bundles its own version of the kernel with a unique blend of code libraries, utilities, and applications. Each also offers its own style of system configuration and management. Because of this, introducing more than one or two distinct distributions into a given environment is usually asking for trouble.

For business use, a distribution backed by commercial support is the best choice. Even if you have Linux experience in-house, a single unforeseen crisis can cause IT costs to skyrocket when you have nowhere to call for help.

For this reason, set realistic expectations early in the decision-making process: Linux isn't going to be free. It will, however, be cheap. The software itself is free, which means that the traditional costs associated with regular upgrade cycles are virtually eliminated. It's easier to evaluate the success of a Linux migration if you focus on long-term goals.

The traditional "big two" Linux vendors, and , each offer a desktop Linux distribution backed by commercial support. Either is suitable for large-scale enterprise use, and indeed, very large organizations may want to limit their search to these two choices.

If you can afford to be flexible, however, the desktop Linux market includes a number of -- including , , , and , among others -- that specialize in delivering a high-quality user experience and are similarly backed by commercial support. The exact best fit will largely be a matter of personal taste.

Will it run with Linux?
One way Linux distributions distinguish themselves is through ease of installation and configuration on a variety of hardware. Overall, hardware support in modern Linux systems is very good and continues to improve. In fact, Linux may actually offer for some legacy hardware than newer proprietary operating systems such as Windows Vista.

Occasionally, though, a particular hardware vendor may be , leaving you with limited or no support under Linux. Typical trouble areas include certain graphics cards and wireless networking hardware, as well as laptop power-management features such as suspend and hibernate.

Remember, also, to consider hardware beyond the PC itself. If your organization makes use of networked printers, scanners, fax servers, VPN gateways, or other workgroup-centered hardware, you'll need to make sure that Linux drivers are available for these devices, too. Your Linux vendor should be able to answer any questions, but be prepared for occasional bad news.

Inconsistent hardware support can make deploying Linux on a wide scale a challenge. Unfortunately, you can't expect any single Linux distribution to behave identically on every PC. Some hardware configurations will always exhibit quirks or glitches that aren't present on others.

Standardizing hardware is your best chance for a smooth installation experience, but this isn't always easy. Even if you identify an ideal PC configuration today, will you still be able to purchase the same machine next year, when your company grows?

Fortunately, an increasing number of hardware vendors are offering systems that are certified for use with Linux, or even ship with Linux pre-installed. offers several , for example, while and favor Suse. If you can purchase Linux-certified hardware consistently, it can save you a lot of headaches in the long run.

Linux: It's the applications, stupid
A Linux desktop is more than just the OS. Before you start migrating users to Linux, you'll need to make sure that you can provide software to support all of your organization's essential business functions -- and, most likely, a few you never considered.

Equally important, don't assume that you'll be able to get everything for free. Every major Linux distribution offers repositories of free open source applications that can often be worthy substitutes for commercial Windows software. Occasionally, however, purchasing commercial software for Linux may be the only adequate solution.

The ability to integrate Linux desktops with essential back-end systems and business processes will be crucial to your success. As a general rule, it is easier to support administrative staff on Linux than so-called knowledge workers, but even a front-desk receptionist will need access to certain core capabilities.

Take e-mail, for example. Basic messaging should be no problem under Linux, but more advanced groupware functionality -- such as shared calendaring -- presents a bigger challenge. IBM offers a , and the open source can integrate with Exchange Server, but neither solution is likely to sit well with groupware power users. And forget about SharePoint; Linux users are shut out.

do exist, but switching may not be a realistic option. The associated with replacing a heavily loaded Exchange Server may simply be too great. Also, inadequate integration with Active Directory, for example, can hamper Linux in a corporate environment.

Frustrations like these are inevitable: This is at work. As a general rule, the leading Linux applications support most of the functionality that users expect from their categories, but proprietary protocols and closed APIs can thwart true compatibility. To expect a one-to-one replacement for every feature of a specific commercial application would be unrealistic.

The same holds true even for basic desktop productivity software. For example, Linux applications handle files saved by Office 2003 and earlier well, but they for the newer Office 2007 file formats. You'll need to examine the actual workflows within your organization carefully to determine whether it will be feasible to migrate away from Office. Ask tough questions.

Bridging Windows and Linux
You may find that certain employees rely heavily on specific Windows software for which there is no adequate Linux equivalent. In such cases, you have several choices, though none is ideal.

One option is to configure desktops as dual-boot systems, which allows the user to select either Linux or Windows from a menu at startup. This isn't very efficient, however, and it can also be problematic; for example, files created under Windows will be accessible from Linux, but not the other way around. Don't be surprised if users lapse into old habits and spend most of their time in Windows.

Another method is to install for Linux, such as or , and run Windows inside a virtual machine. This will allow users to access the Windows applications they need while still performing most of their tasks using Linux software.

These alternatives present two big problems, however. First, they both require a licensed copy of Windows for each machine, negating any cost savings of Linux. Second, they effectively split each workstation into two complete systems, doubling the IT management workload. Because of this, neither method is a viable long-term solution, so should only be used as a stopgap measure while you phase out Windows.

A third solution is to use , a Windows compatibility layer for Linux that allows many Windows applications to run as if they were native Linux software. Not every application works properly with Wine, however -- you should consult the project's to see if your software is compatible. A commercial version called , which offers additional installation and runtime support for selected applications, is also available.

Finally, a number of thin-client solutions, available from such vendors as and , allows Windows applications to run in terminal windows on Linux desktops. This method has the additional advantage of favoring lower-end hardware. Be aware, however, that most such solutions will require additional infrastructure investments to get up and running.

Making good on your Linux strategy
Installing Linux onto a few desktops is easy enough. Successfully migrating a large number of PCs, however, calls for centralized management and maintenance capabilities. Windows customers have it easier in this area, although to narrow Microsoft's lead. Still, a healthy number of options are available for managing Linux desktops today.

Here, again, it is helpful to standardize on a single, enterprise-focused Linux vendor. Novell's well-established management software supports both Red Hat and Suse systems, while Red Hat offers centralized software management through its Red Hat Network product (which will soon be ). Users of other distributions may need to search for options from third-party vendors, such as .

The bottom line is that, while Linux is a mature and fully functional desktop OS, the process of migrating away from Windows is complex and should not be undertaken lightly. An effective migration strategy must set realistic goals, plan contingencies, and be flexible enough to change direction in the event of unforeseen roadblocks. Making the break from proprietary software vendors isn't easy, and that's by design. Open source developers have made the first critical steps for you. Now it's up to you to take it the rest of the way.

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