The world of computers has shifted in recent years. 8088s have given way to 64-bit out-of-order executing multiprocessor systems, monochrome green displays have improved to 32-bit true color, and even mainframes have almost disappeared in favor of workstation clusters and client-server based systems. In the modern day business world, the market for server-based operating systems is extremely competitive and very lucrative for the businesses involved. Companies such as Sun Microsystems and Microsoft battle constantly to gain ground in the race to provide a better operating system to sell to their customers. Microsoft's Windows NT and Sun's SunOS/Solaris operating systems are extremely full-featured, usually well supported and fairly efficient in terms of their usage and implementation. However, one of the biggest challenges facing these commercial operating systems today is not whether Microsoft will edge out Sun or vice-versa, but whether non-commercial operating systems, such as Linux or the BSD distributions, will prove strong enough to edge out the bigger corporations. Both Linux and the BSD variants run on many different architectures, have growing application and technical support options, are increasingly efficient, and best of all, are freely available.
One of the main concerns when considering a server for running your business is whether or not the operating system has vendor support for the applications you need and use. Both Sun and Microsoft excel in having major vendors supporting their platforms due to their longevity in the server market and their mass amounts of market share. Linux and BSD however, are slowly and steadily gaining ground against the giants. As the free UNIX systems become more well-known and widespread, vendors such as Netscape, Hewlett Packard and others are investing time and money in providing applications and hardware adapted for these systems.
The portability among these varying systems is improving as well and is a major consideration in their race against each other. For example, if you run Solaris on a SPARC, you can buy a product called SoftWindows (http//www.insignia.com/SoftWindows/) which allows a SunOS user to emulate Microsoft's Windows 95 in a window on the desktop, running virtually all the Windows applications. The rest of the UNIX world also has emulators such as DOSEMU for DOS applications, and WABI or WINE for Windows-based emulations. NT falls short in this respect, lacking well-developed emulators, and it does not easily support the same shell-scripting languages (other than Perl) that can be quickly shared across most UNIX platforms. While this may not seem to hinder NT currently, as Linux and BSD grow up in the corporate market it will become a larger factor. Companies looking to switch from SunOS might find it easier to go with a free operating system which is compatible with their current one, saving the cost of upgrading virtually 100% of their hardware and software.
Software support for your operating system is unquestionably a useful benefit, but what happens if the software for your system is incredibly complex and requires various configuration changes to your operating system? Simply having the product available for a system is not enough; the issue of technical support is extremely important in today's market. Commercial operating systems are well-supported--they have no choice. If a company wants to market an OS today, it must provide timely end-user support to the customer with a problem. Both Microsoft and Sun have corporate support options which involve people working diligently on your problem until it has either been fixed or a workaround has been established. Of course, there are exceptions to this rule and not every problem found is immediately fixed, especially in Microsoft's case. The point is that support is guaranteed (usually) to be there when you have questions. This has been one of the major drawbacks in the free-OS world.
The main method of support for both Linux and BSD is not one on which most corporations would be willing to rely on. Support for Linux and BSD is usually done through either newsgroups or various sources of information on the World Wide Web. No one is required to answer a question posted to a newsgroup, and indeed while most people who organize the individual distributions of each OS will provide support, there is no requirement that they do so. If the system goes down, often it is strictly up to the end-user to dig around and find what information he can to solve the problem. For instance, if a Linux user were to call up Patrick Volkerding (the man behind the Slackware Linux distribution) and tell him he better solve their problems or they will speak to his manager, the user will most likely hear a <click> on the other end of the phone line as he hangs up. An interesting note, however, is that many of the people responsible for the distributions will be more than happy to answer questions. Theo de Raadt, the man behind the OpenBSD distribution, welcomes questions, and often answers (and sometimes argues) questions posted to newsgroups. Good luck in getting Bill Gates to involve himself in a 50-message thread over the ease of installing security patches to Windows NT. The bottom line, however, is that technical support is one of the biggest considerations large companies have when choosing an OS, and while the free-OS world may be catching up, it still has a long way to go.
A third major comparison between server-based operating systems would be how efficient and customizable the system is to an end-user's needs. Differences in this comparison range from extremely high-level (various fonts and colors or virtual desktops) to very low-level (kernel customization, configuration and efficiency). Commercial operating systems tend to be much easier to install, walking you through what needs to be installed and how it will be done. Again, this is a requirement when you are charging money for your software. Making an easier to use product has great appeal and is one of the largest marketing strategies in use today in the computer industry. Both Microsoft and Sun have attempted to make their installations visually pleasant and almost ``hold-your-hand'' simple. The commercial systems also release patches and minor updates to keep their systems usable, for example of NT's service packs or Solaris' update clusters. By charging for their software, the vendors usually feel some degree of responsibility for fixing and updating their products to keep them usable. Sometimes this is free, and other times the software company will change the version or name of its OS and charge customers to upgrade.
The world of the free operating systems works somewhat differently. Many times the installation is so confusing and non-intuitive that 95% of the people who use computers today would not be able or willing to muddle through it. The systems are getting to be more user-friendly, and distributions such as Slackware and Red Hat offer a semi-graphical install which is more intuitive than Open BSD, which goes so far as to require the user to know how many cylinders his hard drive has on it. While this might not be that difficult for a user who is familiar with all the components of his system, a small business owner in need of a simple server might be scared away. The usability issue goes back to the fact that because the developers of these distributions receive no monetary gain for each installation, they can make it as easy or as difficult as they desire, which is completely understandable. The same reasoning applies to patches and updates. Ironically, patches and updates are generally faster to appear when problems arise in these free operating systems because of the nature of support for Linux and BSD. Because the source code to these operating systems is free, many users take it upon themselves to code bug-fixes and produce patches. Updates to low-level software such as the Linux kernel come out frequently, offering better support and many bug fixes over previous versions. This results in faster problem solving and even in the availability of patches which are so obscure that larger vendors such as Microsoft or Sun would not devote the time and resources to providing. Sun has even started to recognize the benefits of enthusiasts and hobbyists using their operating system and has started offering Solaris for free (the user pays just the media and shipping/handling fees--see http://www.sun.com/solaris/freesolaris.html).
Operating systems control how we work, what we work on, and how our businesses are run. As business competition heats up, financial considerations in upgrading and replacing computer equipment can become vital to a company's continued success. Commercial operating systems are tested products which come from a company that will provide support for their product. Most commercial operating systems also provide better software support, as software vendors are willing to develop their products for an environment they know will be well-used and thus profitable. Non-Commercial operating systems offer a number of positive reasons to choose them over a commercial OS, but they still have a couple of key drawbacks. Scarce software support and non-reliable technical support often provide managers with enough reason to choose a commercial operating system over a free one. While many companies are using free operating systems and are very successful at it, most are not willing to stake their business on whether or not their system administrator can figure out why their server is down by looking through a comp.os newsgroup. Just don't be surprised if you come to work one day to find that your company has decided to go with FreeBSD and qmail to run their new mail system rather than upgrading to Windows NT and shelling out the cash for Exchange Server.
Slackware - www.slackware.org (commercial or free download)
Red hat - www.redhat.com (commercial or free download)
Suse - www.suse.com (commercial)
Debian - www.debian.org (free)
Caldera OpenLinux - www.calderasystems.com (commercial)
Other Misc. Linux Distributions - ftp://sunsite.unc.edu/pub/Linux/distributions
Open BSD - www.openbsd.org (free)
FreeBSD - www.freebsd.org (free)
NetBSD - www.netbsd.org (free)
BSDi - www.bsdi.com (commercial)
Solaris/SunOS - www.sun.com/solaris (commercial, free for non-commercial use)
Windows NT - www.microsoft.com/ntserver (commercial)