Optional sections mean you can read the book at different levels, returning to more difficult material when you are ready. Caution boxes highlight procedures that can easily go wrong, giving you guidance before you run into trouble. Tip boxes highlight places in the text where you can save time by doing something differently or when it may be useful or just interesting to have additional information. Security boxes point out places where you can make your system more secure. The security appendix gives you a quick background in system security issues. Concepts are illustrated by practical examples throughout the book. Chapter summaries provide a review of the important points covered in each chapter. Review exercises are included at the end of each chapter for readers who want to hone their skills. Answers to even-numbered exercises are at www.sobell.com. This book provides resources for finding, downloading, and installing software: Web sites, Apt, yum, BitTorrent, and Red Hat Network (RHN). Important GNU tools, including gcc, gdb, GNU Configure and Build Sys-tem, make, gzip, and many others are described in detail. Pointers throughout provide help in obtaining online documentation from many sources including the local system, the Red Hat Web site, and other locations on the Internet. Many useful URLs (Internet addresses) point to sites where you can obtain software, security programs and information, and more.

Table of Contents

Preface xxxvChapter 1: Welcome to Linux 1 The GNU-Linux Connection 2 The Linux 2.6 Kernel 5 The Heritage of Linux: UNIX 5 What Is So Good About Linux? 6 Overview of Linux 10 Additional Features of Linux 14 Conventions Used in This Book 17 Chapter Summary 19 Exercises 19 PART I: Installing Red Hat Linux 21Chapter 2: Installation Overview 23 More Information 24 Planning the Installation 24 How the Installation Works 33 The Medium: Where Is the Source Data? 34 Downloading, Burning, and Installing a CD Set or a DVD (FEDORA) 35 Rescue CD 40 Gathering Information About the System 40 Finding the Installation Manual 41 Chapter Summary 41 Exercises 42 Advanced Exercises 42 Chapter 3: Step-by-Step Installation 43 Installing Red Hat Linux 44 Installation Tasks 58 The X Window System 69 Chapter Summary 77 Exercises 78 Advanced Exercises 78 PART II: Getting Started with Red Hat Linux 79Chapter 4: Introduction to Red Hat Linux 81 Curbing Your Power: Superuser/root Access 82 A Tour of the Red Hat Linux Desktop 82 Getting the Facts: Where to Find Documentation 102 More About Logging In 111 Controlling Windows: Advanced Operations 119 Chapter Summary 122 Exercises 123 Advanced Exercises 124 Chapter 5: The Linux Utilities 125 Special Characters 126 Basic Utilities 127 Working with Files 129 | (Pipe): Communicates Between Processes 136 Four More Utilities 137 Compressing and Archiving Files 139 Locating Commands 144 Obtaining User and System Information 146 Communicating with Other Users 150 Email 152 Tutorial: Creating and Editing a File with vim 152 Chapter Summary 159 Exercises 162 Advanced Exercises 163 Chapter 6: The Linux Filesystem 165 The Hierarchical Filesystem 166 Directory Files and Ordinary Files 166 Pathnames 171 Directory Commands 173 Working with Directories 178 Access Permissions 180 ACLs: Access Control Lists 185 Links 190 Chapter Summary 196 Exercises 198 Advanced Exercises 200 Chapter 7: The Shell 201 The Command Line 202 Standard Input and Standard Output 208 Running a Program in the Background 219 Filename Generation/Pathname Expansion 221 Builtins 225 Chapter Summary 226 Exercises 227 Advanced Exercises 228 PART III: Digging into Red Hat Linux 231Chapter 8: Linux GUIs: X, GNOME, and KDE 233 X Window System 234 Using GNOME 242 Using KDE 252 Chapter Summary 262 Exercises 264 Advanced Exercises 264 Chapter 9: The Bourne Again Shell 265 Background 266 Shell Basics 267 Parameters and Variables 285 Special Characters 299 Processes 300 History 302 Aliases 318 Functions 321 Controlling bash Features and Options 324 Processing the Command Line 328 Chapter Summary 337 Exercises 339 Advanced Exercises 341 Chapter 10: Networking and the Internet 343 Types of Networks and How They Work 345 Communicate Over a Network 360 Network Utilities 362 Distributed Computing 369 Usenet 378 WWW: World Wide Web 381 Chapter Summary 383 Exercises 384 Advanced Exercises 385 PART IV: System Administration 387Chapter 11: System Administration: Core Concepts 389 System Administrator and Superuser 391 Rescue Mode 397 SELinux 400 System Operation 403 System Administration Utilities 415 Setting Up a Server 421 nsswitch.conf: Which Service to Look at First 435 PAM 438 Chapter Summary 443 Exercises 444 Advanced Exercises 445 Chapter 12: Files, Directories, and Filesystems 447 Important Files and Directories 448 File Types 459 Filesystems 464 Chapter Summary 473 Exercises 474 Advanced Exercises 474 Chapter 13: Downloading and Installing Software 475 yum: Keeps the System Up-to-Date (FEDORA) 476 pirut: Adds and Removes Software Packages (FEDORA) 483 BitTorrent (FEDORA) 484 rpm: Red Hat Package Manager 487 Installing Non-rpm Software 491 Keeping Software Up-to-Date 493 wget: Downloads Files Noninteractively 500 Chapter Summary 500 Exercises 501 Advanced Exercises 501 Chapter 14: Printing with CUPS 503 Introduction 504 JumpStart I: Configuring a Local Printer Using system-config-printer 505 JumpStart II: Configuring a Remote Printer Using CUPS 508 Traditional UNIX Printing 510 Configuring Printers Using CUPS 512 The KDE Printing Manager 519 Integration with Windows 520 Chapter Summary 522 Exercises 522 Advanced Exercises 523 Chapter 15: Rebuilding the Linux Kernel 525 Preparing the Source Code 526 Read the Documentation 528 Configuring and Compiling the Linux Kernel 529 Installing the Kernel and Associated Files 532 Rebooting 532 Boot Loader 533 dmesg: Displays Kernel Messages 535 Chapter Summary 535 Exercises 536 Advanced Exercises 536 Chapter 16: Administration Tasks 537 Configuring User and Group Accounts 538 Backing Up Files 540 Scheduling Tasks 547 System Reports 548 Keeping Users Informed 551 Creating Problems 552 Solving Problems 553 Chapter Summary 564 Exercises 564 Advanced Exercises 565 Chapter 17: Configuring a LAN 567 Setting Up the Hardware 568 Configuring the Systems 570 Setting Up Servers 574 More Information 575 Chapter Summary 575 Exercises 576 Advanced Exercises 576 PART V: Using Clients and Setting Up Servers 577Chapter 18: OpenSSH: Secure Network Communication 579 Introduction 580 About OpenSSH 580 OpenSSH Clients 583 sshd: OpenSSH Server 591 Troubleshooting 595 Tunneling/Port Forwarding 596 Chapter Summary 598 Exercises 598 Advanced Exercises 599 Chapter 19: FTP: Transferring Files Across a Network 601 Introduction 602 More Information 603 FTP Client 603 FTP Server (vsftpd) 612 Chapter Summary 624 Exercises 625 Advanced Exercises 625 Chapter 20: sendmail: Setting Up Mail Clients, Servers, and More 627 Introduction 628 JumpStart I: Configuring sendmail on a Client 630 JumpStart II: Configuring sendmail on a Server 631 How sendmail Works 632 Configuring sendmail 635 Additional Email Tools 640 Authenticated Relaying 650 Alternatives to sendmail 652 Chapter Summary 652 Exercises 653 Advanced Exercises 653 Chapter 21: NIS: Network Information Service 655 Introduction to NIS 656 How NIS Works 656 Setting Up an NIS Client 659 Setting Up an NIS Server 663 Chapter Summary 670 Exercises 670 Advanced Exercises 671 Chapter 22: NFS: Sharing Filesystems 673 Introduction 674 More Information 676 Setting Up an NFS Client 676 Setting Up an NFS Server 682 automount: Automatically Mounts Directory Hierarchies 690 Chapter Summary 692 Exercises 692 Advanced Exercises 693 Chapter 23: Samba: Integrating Linux and Windows 695 Introduction 696 About Samba 697 JumpStart: Configuring a Samba Server Using system-config-samba 699 swat: Configures a Samba Server 701 Manually Configuring a Samba Server 705 Accessing Linux Shares from Windows 711 Accessing Windows Shares from Linux 712 Troubleshooting 714 Chapter Summary 716 Exercises 717 Advanced Exercises 717 Chapter 24: DNS/BIND: Tracking Domain Names and Addresses 719 Introduction to DNS 720 About DNS 731 JumpStart I: Setting Up a DNS Cache 733 JumpStart II: Setting Up a Domain Using system-config-bind (FEDORA) 734 Setting Up BIND 739 Troubleshooting 751 A Full-Functioned Nameserver 752 A Slave Server 756 A Split Horizon Server 757 Chapter Summary 761 Exercises 762 Advanced Exercises 762 Chapter 25: iptables: Setting Up a Firewall 763 How iptables Works 764 About iptables 766 JumpStart: Building a Firewall Using system-config-securitylevel 768 Anatomy of an iptables Command 769 Building a Set of Rules 770 system-config-securitylevel: Generates a Set of Rules 777 Sharing an Internet Connection Using NAT 779 Chapter Summary 783 Exercises 783 Advanced Exercises 784 Chapter 26: Apache (httpd): Setting Up a Web Server 785 Introduction 786 About Apache 786 JumpStart I: Getting Apache Up and Running 789 JumpStart II: Setting Up Apache Using system-config-httpd 790 Filesystem Layout 792 Configuration Directives 794 The Red Hat httpd.conf File 814 Redirects 817 Multiviews 818 Server-Generated Directory Listings (Indexing) 818 Virtual Hosts 818 Troubleshooting 819 Modules 820 webalizer: Analyzes Web Traffic 825 MRTG: Monitors Traffic Loads 826 Error Codes 826 Chapter Summary 827 Exercises 828 Advanced Exercises 828 PART VI: Programming 829Chapter 27: Programming Tools 831 Programming in C 832 Using Shared Libraries 840 make: Keeps a Set of Programs Current 842 Debugging C Programs 850 Threads 860 System Calls 861 Source Code Management 863 Chapter Summary 873 Exercises 874 Advanced Exercises 875 Chapter 28: Programming the Bourne Again Shell 877 Control Structures 878 File Descriptors 911 Parameters and Variables 914 Builtin Commands 926 Expressions 940 Shell Programs 948 Chapter Summary 958 Exercises 960 Advanced Exercises 962 PART VII: Appendixes 965Appendix A: Regular Expressions 967 Characters 968 Delimiters 968 Simple Strings 968 Special Characters 968 Rules 971 Bracketing Expressions 972 The Replacement String 972 Extended Regular Expressions 973 Appendix Summary 975 Appendix B: Help 977 Solving a Problem 978 Finding Linux-Related Information 979 Specifying a Terminal 984 Appendix C: Security 987 Encryption 988 File Security 993 Email Security 993 Network Security 994 Host Security 997 Security Resources 1002 Appendix Summary 1005 Appendix D: The Free Software Definition 1007Appendix E: The Linux 2.6 Kernel 1011 Native Posix Thread Library (NPTL) 1012 IPSecurity (IPSec) 1012 Asynchronous I/O (AIO) 1012 O(1) Scheduler 1013 OProfile 1013 kksymoops 1013 Reverse Map Virtual Memory (rmap VM) 1013 HugeTLBFS: Translation Look-Aside Buffer Filesystem 1014 remap_file_pages 1014 2.6 Network Stack Features (IGMPv3, IPv6, and Others) 1014 Internet Protocol Virtual Server (IPVS) 1014 Access Control Lists (ACLs) 1015 4GB-4GB Memory Split: Physical Address Extension (PAE) 1015 Scheduler Support for HyperThreaded CPUs 1015 Block I/O (BIO) Block Layer 1015 Support for Filesystems Larger Than 2 Terabytes 1016 New I/O Elevators 1016 Interactive Scheduler Response Tuning 1016 Glossary 1017Index 1065

Author Biography

Mark G. Sobell is president of Sobell Associates Inc., a consulting firm that specializes in UNIX/Linux training, support, and custom software development. He is the author of many best-selling UNIX and Linux books and has more than twenty-five years of experience working with UNIX and Linux.