This is not just a Linux book. This is the Linux book. Anyone can write some theoretical book about the way networks should run, but how many of these authors are actually network administrators? How many are stuck in the trenches, reading the cryptic man pages to printcap while users are complaining about their printouts? We've been there, we are there, we will be there. We enjoy it.

The proof of this attitude exists throughout the book. While everyone else goes on about IDE drives, we personally and professionally recognize the power of the small computer systems interface (SCSI) bus and use it in our systems. It's more expensive and, at times, a pain to work with, but the benefits are enormous.

Anyone can tell you how a program like Samba is set up, but what happens in the real world where things aren't quite the same as they are in the man pages?

The UNIX theory is "Do it your way," but Linux is more than a slogan for a chain of hamburgers. Linux allows you to not only choose what you want on your hamburger, but also what's in it, how the cow is grown, what spices are added to the mixture, and how long it is cooked. Linux gives you all the same abilities that commercial UNIX packages (such as Solaris or AIX) give, plus a lot more.

Yes and no. The Gnu's Not UNIX (GNU) Public License (which is how Linux is licensed) says that you can charge for a binary distribution, but the source code must be either included or available for the cost of duplication. In these days of the Internet and CD-ROMs, the cost for duplicating is low indeed.

Note that this really covers only the Linux kernel, and the GNU utilities included with most distributions. This does not prevent a company like Red Hat from assembling all these programs, adding a few special ones (installation and administration scripts, for example), producing a CD-ROM, and charging you $80 for it. The Linux kernel and source code is there. The source code to all the other GNU utilities is either also available or pointers to the source code exist. Thus, these companies have met their end of the GNU license. Many of these also sponsor Linux-related events or offer free CD-ROMs to software contributors.

Companies such as Red Hat have a more expensive product, but they add things that may not be covered by the GNU Public License (GPL). For example, Red Hat sells a copy of their distribution for three different architectures for about $80.

So why would you (or your company) want to use Linux in a personal or business setting? The answer goes past the shortsighted "anti-Microsoft" response. Microsoft makes a fair product for a new user. But so does Apple. Linux gives you things that Windows 95 can only dream about:

As an inexpensive Web server, Linux will beat NT hands down for performance on equivalent hardware. As a network server, a Linux machine hidden in the corner of an office can handle a small workgroup or a large office with months between reboots (usually to either upgrade the kernel or add new hardware). With the emergence of Java^[1] as a truly portable language, companies can easily port their software to Linux just as fast as applications for NT or Windows 98. Many commercial applications (Netscape, WordPerfect, Applix, Motif, Oracle) are already available for Linux, with more being added.

The simple answer to this is "Yes." Linux takes the best of System Five (SYSV) (like startup files) and the Berkley System Distribution (BSD) (ps aux, getty) and combines them. As a downside, some features of each are missing (like streams) and you should make yourself aware of what features of each are in Linux. If you're compiling or porting software, you will probably find better luck writing towards BSD. Check the man pages for system calls for more information on this.

Contrary to popular belief, commercial support for Linux is available. While there is seldom a need for it, Red Hat has telephone and email support for their Linux distribution. With the number of users that have Linux on their machines, devices from the latest 3Dfx-based 3D cards to the Mattel PowerGlove have drivers available, and everything in between. The support is often somewhat better than from other operating systems, as the author of a particular driver is sometimes available via email and is often willing to help if your driver is not behaving properly. Some hardware drivers have released patches within 24 hours to users.

More companies are starting to add 24×7 support for Linux, including large companies such as HP.

So what do you need to run Linux? It varies greatly, depending on what you want to do with it. If you're going to use Linux to dial up the Internet, a low-end Pentium will suffice. If you want to have a dial-in pool to give access to traveling engineers or salespeople, a 100-Mhz 486 is great. If you want a killer development system or something to write a book with, a Pentium II or K6-III will do just fine.

What? You have a spare Sparc Classic with nothing better to do? Turn it into a Linux Samba server. Let the people running Windows 98 or NT access Network File System (NFS) partitions without having all that messy NFS software installed on their PCs. While it's doing that, it could also handle POP email for the same group of people.

You just bought that great new Alpha machine and NT is having trouble with it? Slap Linux on there and be up and running before you remember what NT stands for.

Here are the minimum suggestions for running Linux:

Once you have these items assembled, you can use the instructions with the Linux distribution to install Linux on your system.

Red Hat recommends the following for installation:

See the next chapter for information on installing Red Hat.