Error 404--Not Found
From RFC 2068 Hypertext Transfer Protocol -- HTTP/1.1:
10.4.5 404 Not Found
The server has not found anything matching the Request-URI. No indication is given of whether the condition is temporary or permanent.
If the server does not wish to make this information available to the client, the status code 403 (Forbidden) can be used instead. The 410 (Gone) status code SHOULD be used if the server knows, through some internally configurable mechanism, that an old resource is permanently unavailable and has no forwarding address.
Lookin' into Linux
Set aside those operating system biases. If you're delivering intranet services, you've got to check out the Linux program -- it's free, fast and feature-rich.
By Mark Gibbs
In a world in which it's assumed that only geeks love Unix, a lot of otherwise cool intranet managers might be missing a great opportunity to build their corporate Webs on a fast, free, resource-friendly operating system: Linux.
This hugely popular Unix program is installed on an estimated six million computers worldwide. Some of those Linux machines are serving intranet users at the University of Nebraska Press, in Lincoln.
"The Linux server has proven to be as reliable as any other server operating system I have ever used, and more reliable than most," says Quinn Coldiron, systems department manager, in a white paper on his organization's deployment.
The University of Nebraska Press turned to Linux when looking to replace an aging Novell, Inc. NetWare server. Coldiron says his first inclination was to go with Microsoft Corp.'s Windows NT Server 4.0, but also decided to set up a test Linux server to see if that operating system could handle the organization's application load.
From January to July 1997, the test Linux server only shut down three times Ÿ twice because of power failures in the building and once because of stupid administration, Coldiron says. "This reliability was a key factor in our judgment to use Linux as our server platform," he adds.
Tales such as Coldiron's notwithstanding, many other IT professionals lump Linux among the other Unix variants they so disdain.
"Non-Unix people perceive [Unix] as intended for tech types and, therefore, inferior to an operating system such as NT," says Steven Handleman, director of communications services for a money management firm in Philadelphia, of the prevailing attitude.
The folks who perceive Windows NT, Unix's main competition these days, as easier to use and just as robust as Unix might be right on the first count but are definitely wrong on the second, Handleman argues.
'Should we or shouldn't we use Unix?' is an age-old question that many IT managers have passionately pondered. And now, with the proliferation of HTTP and other intranet-related servers, the operating system issue comes under an intensifying spotlight.
On face value, the Unix operating system in general should be highly desirable for intranets. It is widely recognized as a mature, well-understood, highly scaleable, robust, high-performance operating system supported by multiple vendors.
But there is a downside among these sterling characteristics. Unix is more cumbersome and complex than NT, says Randall Truitt, senior consultant at The-Web Communications, Inc., a consultant firm in Annapolis, Md.
So some intranet managers might simply prefer NT because it's easier to use than Unix. But others cite another reason to ignore Unix. It seems that a really powerful inducement to go with Windows NT is political pressure.
"I know three companies that are silently putting more and more into Unix . . . at the expense of NT, simply because NT falls over too often," says Peter Flynn, a consultant in Cork, Ireland. NT is known to crash too frequently for many IT manager's tastes. Typical causes are memory access violations and I/O errors.
These companies aren't inclined to talk about their decisions "because of pressure from upstairs," Flynn says. "The buy-Microsoft-only ethos has taken over from the buy-IBM-only, and managers who decided [against advice from technology people] to use NT rather than Unix are now unwilling to lose face," he adds.
Now the picture comes into view: bringing in Unix to run an intranet may be more than just a technical gamble, it may be a career inhibitor. Oddly enough, running an intranet on Unix isn't that much of a risk, especially if you chose Linux, the hands-down favorite among the freeware systems.
Linux derives its name from Linus Torvalds, who in 1991 began developing the operating system because he was dissatisfied with the capabilities of the DOS version running on his new IBM 386-based PC. Torvalds, who was an undergraduate at the University of Helsinki, really wanted to use Unix but couldn't afford a commercial version. Writing his own Unix system was the next best thing.
What started as a one-man attempt soon grew into a major development effort. Over the Internet, Torvalds assembled a group of like-minded programmers and by 1992 the first version of Linux became available. Torvalds makes sure the system is freely available, although he and a number of other authors retain rights to the code they developed.
A number of organizations, Red Hat Software, Inc. and Caldera, Inc. among them, have added software to the Linux base code, or kernel. This creates "distributions," which are, in effect, complete, ready-to-run systems.
Each distribution has its own orientation. With its distribution, for example, Red Hat aims to provide a richly featured system. Meanwhile, the non-profit Stampede organization focuses on performance in its distribution.
The Linux applications market also is growing. For example, there's the Raima Database Manager++ database from Raima Corp., in Seattle; FreeBuilder, a free, high-quality Java IDE compiler and the Corel WordPerfect 7 word processor under license from Software Development Corp., in Provo, Utah.
There are even emulators that allow most Macintosh and Windows applications to run under Linux. Abacus Research and Development, Inc., in Albuquerque, N.M., for example, offers a full-featured Macintosh emulator called Executor.
Like a few of its counterparts, such as Berkeley Software Design, Inc.'s BSD Unix and the freeware Minix, Linux runs not only on Intel Corp. processors but a variety of other platforms. For Linux, those include the PowerPC 601, 603 and 604, Acorn Archimedes, Digital Equipment Corp.'s StrongARM and Alpha MIPS processors, Motorola, Inc.'s 68000, Apple Computer, Inc.'s Mach Microkernel for PPC Macintosh, and Sun Microsystems, Inc.'s SPARC processors.
These versions of Unix that run on generic platforms differ from those offered by the big boys of the industry: Digital, Hewlett-Packard Co., IBM, Silicon Graphics, Inc. and Sun. Such vendors offer Unix systems for workstations on up through top-end servers. But no matter how good their products are, if you're not a Sun shop, for example, you probably don't want to buy Sun's Solaris system. Buying into new hardware, particularly hardware that locks you in, is usually seen as a much bigger commitment than buying into new software.
With a system such as Linux, you get the executable code at no cost as well as the source code. Dynamic intranet groups ought to find appeal in the opportunity of fixing their own problems and creating customized platforms.
Worth a gamble?
Before you consider making Linux a cornerstone of your intranet, you need to consider the degree of risk involved. It is generally agreed that the key risk issues in any server rollout are implementation and on-going costs, performance and support.
When it comes to implementation cost, Linux is always cheaper than the likes of Windows NT. And installation is not much harder than it is for Windows NT, although the choice of additional hardware such as adapter cards is more limited for Linux.
What's more, top-end performance for Linux can be achieved with modest processors. And Linux doesn't restrict your platform choice. Red Hat Linux, for example, runs on a greater range of PC hardware than any operating system but Windows 95, says Bob Young, CEO of the Research Triangle Park, N.C., company (see sidebar, page xx).
Support, Linux aficionados argue, is just as good if not better than the competition. A support query posted to one of the many Usenet newsgroups on Linux draws an answer in about 15 minutes, they say.
And don't "for a minute discount the value" of newsgroups and lists, Young says. He points to the fact that the technical support columnist at InfoWorld, a sister publication of Network World, gave the Linux community his technical support award for 1997.
However, if you're not comfortable with a reliance of newsgroup participants, you can hire out support from a number of companies. Red Hat, for example, is developing a worldwide partnership program for supporting its Linux distribution. It already has signed on Collective Technologies, in Austin, Texas.
If you're now even slightly convinced that Linux might have a place on your intranet, try it. Grab an old 486 PC, load one of the Linux distributions or download a copy from one of the many archives, and check it out. You'll find that Linux is a different and effective way of providing intranet services and one that could save you a lot of money in the process.
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