Emmett Dulaney
8

IN
1
BOOKS
BOOKS
• Linux Basics
• Linux Desktops
• Networking
• The Internet
• Administration
• Security
• Linux Servers
• Programming
Linux
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ALL-IN-ONE
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Complete instructions for installing and using each distribution
Please see the DVD appendix for complete system requirements.
Open the book and find:
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you need to know about installing, configuring, and using
Linux, while the DVD gives you five Linux flavors to sample.
• It’s a do-it-yourself thing — learn the essentials of installing and
using Linux by checking out Books I and II
• All about access — connect to the Internet, configure and manage
TCP/IP networks, and set up e-mail, newsgroups, and Web surfing
• Administrative stuff — manage user accounts, install
applications, work with peripherals, and upgrade or customize
the Linux kernel
• Safety first — secure the network and the host, and perform
regular security audits
• Serve it up — configure an Apache Web server, set up an FTP
server or a Windows® server, and explore Linux programming
Ubuntu, Fedora,
and more
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Linux
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Dulaney
4th Edition
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Linux
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4TH EDITION
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by Emmett Dulaney
Linux
®
ALL-IN-ONE
FOR
DUMmIES
‰
4TH EDITION
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Linux
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Library of Congress Control Number: 2010933460
ISBN: 978-0-470-77019-1
Manufactured in the United States of America
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Dedication
For Karen, Kristin, Evan, and Spencer.
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About the Author

(Previous Edition: Jen Riggs)
Technical Editor: Elizabeth Zinkann
Editorial Manager: Jodi Jensen
Editorial Assistant: Leslie Saxman
Sr. Editorial Assistant: Cherie Case
Cartoons: Rich Tennant
(www.the5thwave.com)
Composition Services
Project Coordinator: Sheree Montgomery
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Proofreaders: Melissa Cossell,
The Well-Chosen Word
Indexer: Sherry Massey
Publishing and Editorial for Technology Dummies
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Composition Services
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Contents at a Glance
Introduction 1
Book I: Linux Basics 7
Chapter 1: Introducing Linux 9
Chapter 2: Installing Linux 31
Chapter 3: Installing Linux on a Flash Drive 41

Book VII: Linux Servers 453
Chapter 1: Managing Internet Services 455
Chapter 2: Managing Mail and News Servers 473
Chapter 3: Managing DNS 495
Chapter 4: Working with Samba and NFS 515
Book VIII: Programming 525
Chapter 1: Programming in Linux 527
Chapter 2: Introductory Shell Scripting 553
Chapter 3: Advanced Shell Scripting 565
Appendix: About the DVD 573
Index 589
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Table of Contents
Introduction 1
About This Book 2
Conventions Used in This Book 2
What You Don’t Have to Read 3
Who Are You? 3
How This Book Is Organized 3
What’s on the DVD? 5
Icons Used in This Book 5
Where to Go from Here 6
Book I: Linux Basics 7
Chapter 1: Introducing Linux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
What Is Linux? 9
Linux distributions 11
Making sense of version numbers 14
Linux Standard Base (LSB) 15
Contents of a Linux Distribution 16

Working Daily with the New Drive 44
Chapter 4: Troubleshooting and Confi guring Linux . . . . . . . . . . . . . . . .45
Using Text Mode Installation 46
Troubleshooting X 46
Resolving Other Installation Problems 48
Using Knoppix boot commands 48
The fatal signal 11 error 51
Getting around the PC reboot problem 51
Using Linux kernel boot options 51
Setting Up Printers 55
Managing DVDs and CD-ROMs 58
Installing Other Software 58
Installing software in Debian and Ubuntu 58
Installing software in Fedora 61
Installing software in SUSE 62
Installing software in Xandros 62
Chapter 5: Trying Out Linux . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Starting Linux 65
Playing with the Shell 68
Starting the bash shell 69
Understanding shell commands 70
Trying a few Linux commands 70
Shutting Down 72
Book II: Linux Desktops 75
Chapter 1: The GNOME Desktop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Getting to Know the GNOME Desktop 78
Desktop context menus 78
Icon context menus 79
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Working with date and time 113
Processing  les 114
Writing Shell Scripts 117
Chapter 4: Navigating the Linux File System . . . . . . . . . . . . . . . . . . . .119
Understanding the Linux File System 119
Navigating the File System with Linux Commands 124
Commands for directory navigation 124
Commands for directory listings and permissions 126
Commands for changing permissions and ownerships 128
Commands for working with  les 129
Commands for working with directories 130
Commands for  nding  les 131
Commands for mounting and unmounting 132
Commands for checking disk-space usage 133
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Linux All-in-One For Dummies, 4th Edition
xvi
Chapter 5: Introducing Linux Applications . . . . . . . . . . . . . . . . . . . . . .137
Taking Stock of Linux Applications 137
Introducing Of ce Applications and Tools 143
OpenOf ce.org of ce suite 143
Calendars 147
Calculators 148
Checking out Multimedia Applications 149
Using a digital camera 149
Playing audio CDs 150
Playing sound  les 151
Burning a CD 151
Using Graphics and Imaging Apps 152

Understanding TCP/IP 195
IP addresses 197
Internet services and port numbers 198
Setting Up an Ethernet LAN 199
How Ethernet works 200
Ethernet cables 201
Con guring TCP/IP Networking 203
Connecting Your LAN to the Internet 204
Chapter 3: Going Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .207
Understanding Wireless Ethernet Networks 207
Understanding infrastructure and ad hoc modes 208
Understanding Wired Equivalent Privacy (WEP) 209
Setting Up Wireless Hardware 211
Con guring the Wireless Access Point 212
Con guring Wireless Networking 213
Chapter 4: Managing the Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . .217
Discovering the TCP/IP Con guration Files 217
/etc/hosts 218
/etc/networks 219
/etc/host.conf 219
/etc/resolv.conf 219
/etc/hosts.allow 220
/etc/hosts.deny 220
/etc/nsswitch.conf 221
Checking Out TCP/IP Networks 221
Checking the network interfaces 222
Checking the IP routing table 222
Checking connectivity to a host 223
Checking network status 224
Snif ng network packets 225

Understanding Newsgroups 261
Newsgroup hierarchy 262
Top-level newsgroup categories 263
Linux-related newsgroups 264
Reading Newsgroups from Your ISP 266
Taking stock of newsreaders 266
Reading newsgroups with Thunderbird 267
Newsgroup subscriptions 269
Posting news 270
Using KNode 271
Reading and Searching Newsgroups at Web Sites 272
Reading RSS Feeds 273
Examining an RSS Feed 274
Reading RSS Feeds 275
Chapter 4: Using FTP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .277
Using Graphical FTP Clients 277
Using gFTP 278
Introducing KFTPGrabber 280
Using a Web browser as an FTP client 281
Using the Command-Line FTP Client 283
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Table of Contents
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Book V: Administration 289
Chapter 1: Introducing Basic System Administration . . . . . . . . . . . . .291
Taking Stock of System Administration Tasks 291
Introducing Some GUI Sysadmin Tools 293
GUI sysadmin tools in Debian 293
GUI sysadmin tools in Fedora 293

Scheduling recurring jobs 327
Chapter 2: Managing Users and Groups . . . . . . . . . . . . . . . . . . . . . . . .331
Adding User Accounts 331
Managing user accounts by using a GUI user manager 332
Managing user accounts by using commands 334
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Understanding the /etc/passwd File 335
Managing Groups 337
Exploring the User Environment 338
Changing User and Group Ownership of Files 340
Chapter 3: Managing File Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . .343
Exploring the Linux File System 343
Understanding the  le-system hierarchy 344
Mounting a device on the  le system 347
Examining the /etc/fstab  le 349
Sharing Files with NFS 350
Exporting a  le system with NFS 351
Mounting an NFS  le system 352
Backing Up and Restoring Files 352
Selecting a backup strategy and media 353
Commercial backup utilities for Linux 354
Using the tape archiver — tar 354
Accessing a DOS or Windows File System 359
Mounting a DOS or Windows disk partition 359
Mounting those old DOS  oppy disks 360
Mounting an NTFS partition 362
Using mtools 362

Book VI: Security 389
Chapter 1: Introducing Linux Security . . . . . . . . . . . . . . . . . . . . . . . . . .391
Why Worry about Security? 391
Establishing a Security Framework 392
Determining business requirements for security 393
Performing risk analysis 394
Establishing a security policy 395
Implementing security solutions (mitigation) 396
Managing security 397
Securing Linux 397
Understanding the host security issues 398
Understanding network security issues 398
Delving into Computer Security Terminology 399
Keeping Up with Security News and Updates 404
Chapter 2: Securing Linux. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .407
Securing Passwords 407
Shadow passwords 408
Pluggable authentication modules (PAMs) 409
Protecting Files and Directories 410
Viewing ownerships and permissions 410
Changing  le ownerships 411
Changing  le permissions 411
Setting default permission 412
Checking for set user ID permission 413
Encrypting and Signing Files with GnuPG 414
Understanding public key encryption 414
Understanding digital signatures 415
Using GPG 417
Monitoring System Security 421
Securing Internet Services 421

Running Standalone Servers 464
Starting and stopping servers manually 465
Starting servers automatically at boot time 466
Chapter 2: Managing Mail and News Servers . . . . . . . . . . . . . . . . . . .473
Installing the Mail Server 473
Using sendmail 474
A mail-delivery test 474
The mail-delivery mechanism 475
The sendmail con guration  le 476
Syntax of the sendmail.cf  le 481
Other sendmail  les 483
The .forward  le 485
The sendmail alias  le 485
Installing the INN Server 486
Con guring and Starting the INN Server 486
InterNetNews components 487
The incoming.conf  le 491
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Table of Contents
xxiii
The readers.conf  le 492
InterNetNews startup 492
Setting Up Local Newsgroups 493
De ning a newsgroup hierarchy 493
Updating con guration  les 493
Adding the newsgroups 494
Testing your newsgroups 494
Chapter 3: Managing DNS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .495
Understanding Domain Name System (DNS) 495