Fedora®Linux® TOOLBOX 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users Christopher Negus François Caen Wiley Publishing, Inc. 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page iii Fedora® Linux® Toolbox: 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users Published by Wiley Publishing, Inc. 10475 Crosspoint Boulevard Indianapolis, IN 46256 www.wiley.com Copyright © 2008 by Wiley Publishing, Inc., Indianapolis, Indiana Published simultaneously in Canada ISBN: 978-0-470-08291-1 Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 Library of Congress Cataloging-in-Publication Data Negus, Chris, 1957– Fedora Linux toolbox : 1000+ commands for Fedora, Centos and Red Hat power users / Christopher Negus, François Caen. p. cm. Includes index. ISBN 978-0-470-08291-1 (pbk.) 1. Linux. 2. Operating systems (Computers) I. Caen, François. II. Title. 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All other trademarks are the property of their respective owners. Wiley Publishing, Inc. is not associated with any product or vendor mentioned in this book. Wiley also publishes its books in a variety of electronic formats. Some content that appears in print may not be available in electronic books. 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page iv As always, I dedicate my work on this book to my wife, Sheree. — Christopher Negus To my dad, for teaching me BASIC when I was little. — François Caen 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page v 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page vi About the Authors Christopher Negus is the author of the best-selling Fedora and Red Hat Linux Bibles, Linux Toys, Linux Troubleshooting Bible, and Linux Bible 2007 Edition. He is a member of the Madison Linux Users Group. Prior to becoming a full-time writer, Chris served for eight years on development teams for the Unix operating system at AT&T, where Unix was created and developed. He also worked with Novell on Unix development and Caldera Linux. François Caen, through his company Turbosphere LLC, hosts and manages business application infrastructures, with 95 percent running on Linux systems. As an open source advocate, he has lectured on OSS network management and Internet services, and served as president of the Tacoma Linux User Group. François is a Red Hat Certified Engineer (RHCE). In his spare time, François enjoys managing enterprise Cisco networks. 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page vii 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page viii Credits Acquisitions Editor Jenny Watson Development Editor Sara Shlaer Technical Editor Thomas Blader Copy Editor Michael Koch Editorial Manager Mary Beth Wakefield Production Manager Tim Tate Vice President and Executive Group Publisher Richard Swadley Vice President and Executive Publisher Joseph B. Wikert Project Coordinator, Cover Lynsey Osborn Compositor Laurie Stewart, Happenstance Type-O-Rama Proofreader Kathryn Duggan Indexer Melanie Belkin Anniversary Logo Design Richard Pacifico 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page ix Contents at a Glance Chapter 1: Starting with Fedora Linux . . . . . . . . . . . . . . . . . . . . .1 Chapter 2: Installing Fedora and Adding Software . . . . . . . . . . .13 Chapter 3: Using the Shell . . . . . . . . . . . . . . . . . . . . . . . . . . .33 Chapter 4: Working with Files . . . . . . . . . . . . . . . . . . . . . . . . .51 Chapter 5: Manipulating Text . . . . . . . . . . . . . . . . . . . . . . . . . .71 Chapter 6: Playing with Multimedia . . . . . . . . . . . . . . . . . . . . .89 Chapter 7: Administering File Systems . . . . . . . . . . . . . . . . . .103 Chapter 8: Backups and Removable Media . . . . . . . . . . . . . . .131 Chapter 9: Checking and Managing Running Processes . . . . . .147 Chapter 10: Managing the System . . . . . . . . . . . . . . . . . . . . .165 Chapter 11: Managing Network Connections . . . . . . . . . . . . .187 Chapter 12: Accessing Network Resources . . . . . . . . . . . . . . .209 Chapter 13: Doing Remote System Administration . . . . . . . . .229 Chapter 14: Locking Down Security . . . . . . . . . . . . . . . . . . . .247 Appendix A: Using vi or Vim Editors . . . . . . . . . . . . . . . . . . . .263 Appendix B: Shell Special Characters and Variables . . . . . . . .271 Appendix C: Getting Information from /proc . . . . . . . . . . . . . .275 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .281 82911ffirs.qxd:Toolbox 10/19/07 12:41 PM Page x Contents Acknowledgments xix Introduction xxi Chapter 1: Starting with Fedora Linux 1 About Fedora, Red Hat, and Linux 2 Comparing Fedora to Other Linuxes 3 Finding Fedora Resources 4 Focusing on Linux Commands 5 Finding Commands 6 Command Reference Information in Fedora 8 Summary 11 Chapter 2: Installing Fedora and Adding Software 13 Installing Fedora 13 Preparing to Install 14 Choosing Installation Options 14 Answering Installation Questions 17 Working with Software Packages 19 Using yum Software Repositories 20 Enabling Repositories for yum 21 Using the yum Command 23 Using yum Utilities 26 Managing Software with rpm 26 Using the rpm Command 27 Building RPMs from SRPMs 31 Extracting Files from RPMs 31 Summary 32 Chapter 3: Using the Shell 33 Terminal Windows and Shell Access 33 Using Terminal Windows 33 Using Virtual Terminals 35 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xi xii Contents Using the Shell 35 Using Bash History 36 Using Command Line Completion 37 Redirecting stdin and stdout 37 Using alias 40 Watching Commands 41 Watching Files 41 Acquiring Super User Power 41 Using the su Command 41 Delegating Power with sudo 42 Using Environment Variables 43 Creating Simple Shell Scripts 45 Editing and Running a Script 45 Adding Content to Your Script 45 Summary 49 Chapter 4: Working with Files 51 Understanding File Types 51 Using Regular Files 51 Using Directories 52 Using Symbolic and Hard Links 53 Using Device Files 54 Using Named Pipes and Sockets 54 Setting File/Directory Permissions 55 Changing Permissions with chmod 56 Setting the umask 58 Changing Ownership 58 Traversing the File System 59 Copying Files 60 Changing File Attributes 62 Searching for Files 63 Finding Files with locate 63 Locating Files with find 64 Using Other Commands to Find Files 66 Finding Out More About Files 66 Listing Files 67 Verifying Files 67 Summary 69 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xii xiii Contents Chapter 5: Manipulating Text 71 Matching Text with Regular Expressions 71 Editing Text Files 72 Using the JOE Editor 73 Using the pico and nano Editors 76 Graphical Text Editors 78 Listing, Sorting, and Changing Text 78 Listing Text Files 79 Paging Through Text 80 Paginating Text Files with pr 80 Searching for Text with grep 81 Replacing Text with sed 83 Translating or Removing Characters with tr 84 Checking Differences Between Two Files with diff 85 Using awk and cut to Process Columns 87 Converting Text Files to Different Formats 88 Summary 88 Chapter 6: Playing with Multimedia 89 Working with Audio 89 Playing Music 89 Adjusting Audio Levels 91 Ripping CD Music 92 Encoding Music 93 Streaming Music 95 Converting Audio Files 97 Transforming Images 98 Getting Information about Images 98 Converting Images 99 Converting Images in Batches 100 Summary 102 Chapter 7: Administering File Systems 103 Understanding File System Basics 103 Creating and Managing File Systems 105 Partitioning Hard Disks 105 Working with File System Labels 109 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xiii xiv Contents Formatting a File System 110 Viewing and Changing File System Attributes 111 Creating and Using Swap Partitions 113 Mounting and Unmounting File Systems 114 Mounting File Systems from the fstab File 114 Mounting File Systems with the mount Command 116 Unmounting File Systems with umount 119 Checking File Systems 119 Checking RAID Disks 121 Finding Out About File System Use 123 Logical Volume Manager 124 Creating LVM Volumes 125 Using LVM Volumes 127 Growing the LVM Volume 128 Shrinking an LVM Volume 129 Removing LVM Logical Volumes and Groups 129 Summary 130 Chapter 8: Backups and Removable Media 131 Backing Up Data to Compressed Archives 131 Creating Backup Archives with tar 131 Using Compression Tools 133 Listing, Joining, and Adding Files to tar Archives 136 Deleting Files from tar Archives 137 Backing Up Over Networks 137 Backing Up tar Archives Over ssh 137 Backing Up Files with rsync 139 Backing Up with unison 140 Backing Up to Removable Media 141 Creating Backup Images with mkisofs 142 Burning Backup Images with cdrecord 144 Making and Burning DVDs with growisofs 146 Summary 146 Chapter 9: Checking and Managing Running Processes 147 Listing Active Processes 148 Viewing Active Processes with ps 148 Watching Active Processes with top 153 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xiv xv Contents Finding and Controlling Processes 155 Using pgrep to Find Processes 155 Using fuser to Find Processes 156 Changing Running Processes 157 Summary 163 Chapter 10: Managing the System 165 Monitoring Resources 165 Monitoring Memory Use 166 Monitoring CPU Usage 169 Monitoring Storage Devices 172 Mastering Time 174 Changing Time/Date with Graphical Tools 174 Displaying and Setting Your System Clock 175 Displaying and Setting Your Hardware Clock 176 Using Network Time Protocol to Set Date/Time 177 Trying Other Date/Time Commands 178 Managing the Boot Process 178 Using the GRUB Boot Loader 179 Repairing the initial ramdisk (initrd) 180 Controlling Startup and Run Levels 180 Straight to the Kernel 182 Poking at the Hardware 185 Summary 186 Chapter 11: Managing Network Connections 187 Configuring Networks from the GUI 187 Managing Network Interface Cards 188 Managing Network Connections 191 Starting and Stopping Ethernet Connections 191 Viewing Ethernet Connection Information 193 Using Wireless Connections 194 Using Dial-up Modems 196 Checking Name Resolution 199 Troubleshooting Network Problems 201 Checking Connectivity to a Host 201 Checking Address Resolution Protocol (ARP) 202 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xv xvi Contents Tracing Routes to Hosts 203 Displaying netstat Connections and Statistics 206 Other Useful Network Tools 206 Summary 207 Chapter 12: Accessing Network Resources 209 Running Commands to Browse the Web 209 Transferring Files 211 Downloading Files with wget 211 Transferring Files with cURL 212 Transfering Files with FTP Commands 213 Using SSH Tools to Transfer Files 215 Using Windows File Transfer Tools 216 Sharing Remote Directories 217 Sharing Remote Directories with NFS 217 Sharing Remote Directories with Samba 219 Sharing Remote Directories with SSHFS 222 Chatting with Friends in IRC 223 Using Text-Based E-mail Clients 224 Managing E-mail with mail 224 Managing E-mail with mutt 225 Summary 227 Chapter 13: Doing Remote System Administration 229 Doing Remote Login and Tunneling with SSH 229 Configuring SSH 230 Logging in Remotely with ssh 231 Using screen: A Rich Remote Shell 236 Using a Remote Windows Desktop 239 Connecting to a Windows Desktop with tsclient 240 Connecting to a Windows Desktop with rdesktop 241 Using Remote Linux Desktop and Applications 241 Sharing Desktops Using VNC 242 Setting Up the VNC Server 243 Starting Up the VNC Client 243 Using VNC on Untrusted Networks with SSH 244 Sharing a VNC Desktop with Vino 245 Summary 246 82911ftoc.qxd:Toolbox 10/18/07 4:05 PM Page xvi