Red Hat Linux System Administration Handbook

Description

2539E-5

Manage your Red Hat Linux systems for maximum productivity!

Red Hat Linux 6.0 delivers cost-effective, rock-solid networking and Internet connectivity - and with the Red Hat Unux System Administration Handbook, anyone can administer a Red Hat Linux system successfully!

Two top Linux experts walk you step-by-step through everything you'll need to know about Linux networking, user accounts, file and print services, email, security, backups, and much more. You'll get practical, hands-on guidance for configuring your hardware and peripherals - and maximizing the performance of your Linux system.

Coverage includes:

• Technical and practical explanations of every major system administration task
• Deploying Web services, NetNews, FTP, X Windows, Samba, and more
• Managing Linux in heterogeneous networked environments
• Handling Linux system upgrades, and more

You'll find all-new chapters on installation, the PAM Red Hat Security Model, the Red Hat package manager, and the latest 2.2 kernel enhancements — plus detailed coverage of managing Red Hat Linux with the GNOME graphical user interface. If you want to make the most of Red Hat Linux — with the least effort — you want Red Hat Linux System Administration Handbook!

Sample Content

Downloadable Sample Chapter

Click here for a sample chapter for this book: 0130253952.pdf

Table of Contents

1. Introduction.

Oh No! Not Another Linux Book! Linux Theory. Is It Really Free? Why Linux? Is Linux SYSV or BSD? Support. What You Need. Red Hat Recommended Settings.

Getting Linux. Preparing for the Install. Performing the Install. LILO Installation. Linux and Other Operating Systems. Upgrading Red Hat Linux. Migrating from Other Distributions. Applications CD. Summary.

LILO. Kernel Boot. init. What's a Runlevel? When Something Goes Wrong. The Red Hat Rescue Diskette. System Shutdown. Keeping a PC Safe from Reboots. Summary.

Adding Users. Deleting or Disabling Users. Using Shadow Passwords. Using PAM. Linuxconf. Interaction with Users. Summary.

Binary RPM Installation. Source RPM (SRPM). Other RPM Utilities. Summary.

TCP/IP. INETD. Network Applications. AppleTalk. Network Information Services (NIS and NIS+). Routing with Linux. Internet Agencies. Summary.

Connecting Printers to Linux. Serial vs. Parallel vs. Ethernet Printers. Configuring a Printer. Print Filters. Printers on the Network! Managing Print Queues. Ghostscript. Summary.

Setting up a MS Windows Network. Installing Samba. Linux SMB Connections. SWAT (Samba Web Administration Tool). Installing Linux Printers on Windows. Summary.

Using m4 Files. You Have Mail! MIME. The .forward File. Mailing Lists. Qmail: An Alternative to Sendmail. Remote Email (POP and IMAP). Summary.

FTP under Red Hat Linux. Configuring wu-ftpd. Anonymous FTP. ProFTPD. BeroFTPD. TFTP. FTP Clients. Summary.

Office Products, Word Processors, and Editors. Drawing, Graphics, and Image Viewing and Manipulation. Scientific Programs. Emulators. Summary.

MySQL and mSQL. Other Native Linux DMBS's. Summary.

C. C++. Perl. Python. Lisp, Scheme,, and Guile. Java. Tcl/Tk. SQL. PHP. Other Languages. Summary.

Web Server Software. Hardware Issues. Apache and ApacheSSL/Stronghold. Logging. Databases and Web Servers. Setting Up a Killer Web Server. Streaming Audio and Video. Summary.

X Concepts. Setting Up X Using Xconfigurator. Setting Up X Manually. gdm. Using X Window Managers. User Programs. X Resources. X Applications. Using Remote Displays. Major X Libraries. Commercial X Resources. Summary.

Physical Security. Software Security. Denial of Service Attacks. Network Security. Packet Filtering with Linux. Summary.

Customizing Your Kernel. Which Kernel? Getting Ready. Adding Kernels to LILO. Modules or Compiled In? Dive on In! Summary.

Syslog. Network Monitoring. Network Monitoring Distributions. Summary.

tar and mt. cpio. Dump and Restore. Commercial Backup Products. Backup Strategies. RAID and Disk Mirroring. Summary.

Scanners. Modems. Tape Drives. UPS. 3D Cards. USB Support. Adding a New Hard Drive. PCMCIA Devices and Laptop Machines. ZIP and JAZ Drives. Quick Guide to Serial Ports. CD-ROMs and CD-R Writers. Summary.

Overview. Software Versions. Networking. PPP. IP Masquerading. Summary.

URLs To Keep Track Of. URLs Referenced in This Book.

Problems Using Very Large Hard Disks. Linux-allocated Devices. Additional /dev Directory Entries.

Preface

Introduction

What's this Linux thing?

Linux is probably one of the fastest growing operating systems around. It has about 10 million worldwide users, and that number is growing each day. For something that started as an idea by a college student in Finland in 1991, that is pretty darn good.

Linux is now used everywhere there is a need for a good, robust operating system. Companies run their businesses on Linux, but many may not know it. It is used for email servers, WWW servers, and to provide file and printer access for Microsoft and Apple machines, and even other UNIX machines.

This is a guide to give you (the reader) as much knowledge as we (the authors) have attained in our years of Linux administration. Our administrative projects have been varied, but they all have had a common base—managing users, email, the network, hardware, and making sure that we didn't mess up anything too badly while trying to make an improvement.

1.1Oh No! Not Another Linux Book!

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?

1.2Linux Theory

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.

1.3Is It Really Free?

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.

1.4Why Linux?

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:

• Source code for the entire kernel.
• Full configurability of the operating system.
• Ability to turn features of the system on and off without rebooting.
• Full 32-bit operating system, or 64-bit for the Alpha and Sparc series processors. As new chips arrive (Pentium III and Merced), Linux will be ported to these new chips.
• Access to the 25 years of software experience that make up the UNIX world. This includes compilers, Web servers, editors, games, and Internet tools.
• A growing application base with generally rapid and responsive software development, a supportive user community, and growing commercial acceptance.

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 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.

1.5Is Linux SYSV or BSD?

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.

1.6Support

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 24x7 support for Linux, including large companies such as HP.

1.7What You Need

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:

• 386 or better (or Sparc, Alpha, or Macintosh).
• 8 Mb of memory.
• Industry Standard Architecture (ISA), Video Electronics Standards Association (VESA), or Personal Computer Interconnect (PCI) bus.
• Graphics card, monitor, and keyboard.

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

1.8Red Hat Recommended Settings

Red Hat recommends the following for installation:

• 386sx or better CPU, including the Pentium family of processors.
• 120MB of hard drive space for a minimal install. 500MB is recommended for a typical install, and about 800 for a full install of all software on the Red Hat CD. You should set aside more space if it's a development system.
• 16MB of RAM.
• CD-ROM or network card.
• 3.5" floppy (in case you don't support booting from CD-ROM).

See the next chapter for information on installing Red Hat.

Updates

Submit Errata