Introduction xxi Assessment Test xxxix Part I Exam 101-500 1 Chapter 1 Exploring Linux Command-Line Tools 3 Understanding Command-Line Basics 4 Discussing Distributions 4 Reaching a Shell 5 Exploring Your Linux Shell Options 5 Using a Shell 7 Using Environment Variables 11 Getting Help 17 Editing Text Files 20 Looking at Text Editors 20 Understanding vim Modes 24 Exploring Basic Text-Editing Procedures 24 Saving Changes 27 Processing Text Using Filters 28 File-Combining Commands 28 File-Transforming Commands 31 File-Formatting Commands 33 File-Viewing Commands 36 File-Summarizing Commands 40 Using Regular Expressions 45 Using grep 45 Understanding Basic Regular Expressions 47 Understanding Extended Regular Expressions 50 Using Streams, Redirection, and Pipes 50 Redirecting Input and Output 51 Piping Data between Programs 55 Using sed 56 Generating Command Lines 60 Summary 61 Exam Essentials 61 Review Questions 62 Chapter 2 Managing Software and Processes 67 Looking at Package Concepts 68 Using RPM 69 RPM Distributions and Conventions 69 The rpm Command Set 71 Extracting Data from RPMs 77 Using YUM 78 Using ZYpp 83 Using Debian Packages 86 Debian Package File Conventions 87 The dpkg Command Set 87 Looking at the APT Suite 92 Using apt-cache 93 Using apt-get 94 Reconfiguring Packages 97 Managing Shared Libraries 98 Library Principles 98 Locating Library Files 99 Loading Dynamically 100 Library Management Commands 100 Managing Processes 102 Examining Process Lists 102 Employing Multiple Screens 109 Understanding Foreground and Background Processes 116 Managing Process Priorities 120 Sending Signals to Processes 121 Summary 126 Exam Essentials 127 Review Questions 129 Chapter 3 Configuring Hardware 133 Configuring the Firmware and Core Hardware 134 Understanding the Role of Firmware 134 Device Interfaces 136 The / dev Directory 138 The / proc Directory 139 The / sys Directory 143 Working with Devices 144 Hardware Modules 148 Storage Basics 154 Types of Drives 154 Drive Partitions 155 Automatic Drive Detection 155 Storage Alternatives 156 Multipath 156 Logical Volume Manager 157 Using RAID Technology 158 Partitioning Tools 158 Working with fdisk 158 Working with gdisk 161 The GNU parted Command 162 Graphical Tools 163 Understanding Filesystems 164 The Virtual Directory 164 Maneuvering Around the Filesystem 166 Formatting Filesystems 167 Common Filesystem Types 167 Creating Filesystems 169 Mounting Filesystems 170 Manually Mounting Devices 170 Automatically Mounting Devices 172 Managing Filesystems 173 Retrieving Filesystem Stats 173 Filesystem Tools 173 Summary 174 Exam Essentials 175 Review Questions 177 Chapter 4 Managing Files 181 Using File Management Commands 182 Naming and Listing Files 182 Exploring Wildcard Expansion Rules 186 Understanding the File Commands 189 Compressing File Commands 199 Archiving File Commands 202 Managing Links 213 Managing File Ownership 218 Assessing File Ownership 219 Changing a File''s Owner 219 Changing a File''s Group 220 Controlling Access to Files 221 Understanding Permissions 221 Changing a File''s Mode 223 Setting the Default Mode 226 Changing Special Access Modes 228 Locating Files 229 Getting to Know the FHS 229 Employing Tools to Locate Files 231 Summary 239 Exam Essentials 239 Review Questions 241 Chapter 5 Booting, Initializing, and Virtualizing Linux 245 Understanding the Boot Process 246 The Boot Process 246 Extracting Information about the Boot Process 247 Looking at Firmware 249 The BIOS Startup 249 The UEFI Startup 250 Looking at Boot Loaders 251 Boot Loader Principles 251 Using GRUB Legacy as the Boot Loader 251 Using GRUB 2 as the Boot Loader 255 Adding Kernel Boot Parameters 259 Using Alternative Boot Loaders 260 The Initialization Process 261 Using the systemd Initialization Process 262 Exploring Unit Files 263 Focusing on Service Unit Files 265 Focusing on Target Unit Files 268 Looking at systemctl 270 Examining Special systemd Commands 273 Using the SysV Initialization Process 276 Understanding Runlevels 277 Investigating SysVinit Commands 280 Stopping the System 283 Notifying the Users 284 Virtualizing Linux 286 Looking at Virtual Machines 287 Understanding Containers 291 Looking at Infrastructure as a Service 293 Summary 295 Exam Essentials 295 Review Questions 298 Part II Exam 102-500 303 Chapter 6 Configuring the GUI, Localization, and Printing 305 Understanding the GUI 306 Understanding the X11 Architecture 307 Examining X.Org 308 Figuring Out Wayland 309 Managing the GUI 311 Standard GUI Features 311 The X GUI Login System 313 Common Linux Desktop Environments 314 Providing Accessibility 323 Using X11 for Remote Access 325 Remote X11 Connections 326 Tunneling your X11 Connection 326 Using Remote Desktop Software 328 Viewing VNC 328 Grasping Xrdp 330 Exploring NX 332 Studying SPICE 332 Understanding Localization 333 Character Sets 333 Environment Variables 334 Setting Your Locale 335 Installation Locale Decisions 335 Changing Your Locale 336 Looking at Time 338 Working with Time Zones 338 Setting the Time and Date 339 Configuring Printing 343 Summary 345 Exam Essentials 346 Review Questions 348 Chapter 7 Administering the System 353 Managing Users and Groups 354 Understanding Users and Groups 354 Configuring User Accounts 355 Configuring Groups 371 Managing Email 375 Understanding Email 375 Choosing Email Software 376 Working with Email 377 Using Log and Journal Files 384 Examining the syslog Protocol 385 Viewing the History of Linux Logging 387 Logging Basics Using rsyslogd 387 Journaling with systemd-journaldd 394 Maintaining the System Time 403 Understanding Linux Time Concepts 403 Viewing and Setting Time 404 Understanding the Network Time Protocol 408 Using the NTP Daemon 411 Using the chrony Daemon 413 Summary 416 Exam Essentials 416 Review Questions 419 Chapter 8 Configuring Basic Networking 423 Networking Basics 424 The Physical Layer 424 The Network Layer 426 The Transport Layer 430 The Application Layer 431 Configuring Network Features 433 Network Configuration Files 433 Graphical Tools 436 Command-Line Tools 438 Getting Network Settings Automatically 445 Bonding Network Cards 445 Basic Network Troubleshooting 447 Sending Test Packets 447 Tracing Routes 448 Finding Host Information 449 Advanced Network Troubleshooting 452 The netstat Command 452 Examining Sockets 455 The netcat Utility 456 Summary 457 Exam Essentials 458 Review Questions 460 Chapter 9 Writing Scripts 465 Shell Variables 466 Global Environment Variables 466 Local Environment Variables 468 Setting Local Environment Variables 470 Setting Global Environment Variables 472 Locating System Environment Variables 472 Using Command Aliases 474 The Basics of Shell Scripting 475 Running Multiple Commands 475 Redirecting Output 476 Piping Data 477 The Shell Script Format 478 Running the Shell Script 479 Advanced Shell Scripting 481 Displaying Messages 481 Using Variables in Scripts 482 Command-Line Arguments 484 Getting User Input 484 The Exit Status 488 Writing Script Programs 489 Command Substitution 489 Performing Math 490 Logic Statements 492 Loops 496 Functions 498 Running Scripts in Background Mode 500 Running in the Background 501 Running Multiple Background Jobs 502 Running Scripts Without a Console 503 Sending Signals 504 Interrupting a Process 504 Pausing a Process 504 Job Control 506 Viewing Jobs 506 Restarting Stopped Jobs 508 Running Like Clockwork 509 Scheduling a Job Using the at Command 509 Scheduling Regular Scripts 513 Summary 515 Exam Essentials 516 Review Questions 518 Chapter 10 Securing Your System 523 Administering Network Security 524 Disabling Unused Services 524 Using Super Server Restrictions 534 Restricting via TCP Wrappers 538 Administering Local Security 539 Securing Passwords 539 Limiting root Access 543 Auditing User Access.