LPIC-l/CompTIA. Certification. Lmux+ ONE. ALL a IN. (Exams LPIC-1/LX0-101 & LXO-102) Robb H. Tracy EXAM GUIDE. Graw Hill

Transcription

1 ALL a IN ONE LPIC-l/CompTIA t Lmux+ TM Certification EXAM GUIDE (Exams LPIC-1/LX0-101 & LXO-102) Robb H. Tracy TECHNISCHE INFORMATIONSBiBLIOTHEK UNIVER! ivjc Graw Hill BIBUOTHEK VER New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto McGraw-Hill is an independent entity from CompTIA and the Linux Professional Institute (LPI ). This publication and CD may be used in assisting students to prepare for the CompTIA Linux+ exams or the LPIC-1 exam from LPI. Neither CompTIA, nor LPI, nor McGraw-Hill warrant that use of this publication and CD will ensure passing any exam. CompTIA and CompTIA Linux+ are trademarks or registered trademarks of CompTIA in the United States and/or other countries. LPI is a trademark or registered trademark of the Linux Professional Institute. All other trade marks are trademarks of their respective owners.

2 Acknowledgments Introduction xxvii xxix Chapter I Introduction to Linux I The Role and Function of Linux 2 The Historical Development of Linux 4 Linux Distributions 6 Common Linux Roles 8 Linux as a Desktop 8 Linux as a Server 9 Linux as a Firewall 10 Chapter Review 11 Accelerated Review 11 Questions 12 Answers 15 Chapter 2 Working with the Linux Shell 17 How the Linux Shell Works 18 Linux Shells 19 Managing Shell Configuration Files 21 Using the Shell Prompt 24 Entering Commands at the Shell Prompt 24 Using Command History 28 Using Command Completion 30 Getting Help for Linux Commands 31 Using man Pages 33 Using info 39 Working with Environment Variables 42 What Are Environment Variables? 42 Managing Environment Variables 43 Creating a User-Defined Variable 49 Working with Aliases 50 Using Redirection and Piping 52 Standard bash File Descriptors 52 Redirecting Output and Input for Shell Commands 53 Piping Information 56 Chapter Review 58 Accelerated Review 60 Questions 62 Answers 69 XV

3 . IPIC-l/CompTIA Linux+ Certification All-in-One Exam Guide xvi Chapter 3 Using the vi Text Editor 71 The Role and Function of the vi Text Editor 72 Editing Text Files in vi 75 Opening Files in vi 76 vi Modes 77 Working in Insert Mode 79 Working in Command-Line Mode 79 Working in Command Mode 80 Chapter Review 83 Accelerated Review 85 Questions 86 Answers 89 Chapter 4 Managing Linux Files and Directories 91 Linux File Systems and the Filesystem Hierarchy Standard (FHS). 92 The Role of the Linux File System 92 The Hierarchical Structure of the Linux File System 92 Types of Files Used by Linux 99 Finding Files in the Linux File System 101 Using find 101 Using locate 102 Using which 104 Using whereis 104 Using type 104 Managing Directories from the Command Line 106 Navigating the File System 106 Viewing Directory Contents 108 Creating New Directories Ill Copying, Moving, and Deleting Directories Managing Files from the Command Line 112 Creating New Files 112 Viewing File Contents 113 Deleting Files 114 Copying and Moving Files 115 Determining the File Type 115 Working with Link Files 116 Finding Content Within Files 118 Chapter Review 121 Accelerated Review 122 Questions 124 Answers 126 Ill Chapter 5 Installing Linux 127 Designing a Linux Installation 128 Conducting a Needs Assessment 130 Selecting a Distribution 133

4 Contents xvii Verifying System Requirements and Hardware Compatibility 135 Planning the File System 139 Selecting Software Packages 146 Specify User Accounts 147 Gathering Network Information 148 Selecting an Installation Source 149 Installing Linux 156 Configuring Locale Settings 163 Configuring Time Zone Settings 166 How Time Works on Linux 166 Configuring the Time Zone 168 Chapter Review 169 Accelerated Review 171 Questions 174 Answers 179 Chapter 6 Managing the Linux Boot Process 181 The Linux Boot Process 181 The BIOS Phase 183 The Bootloader Phase 184 The Kernel Phase 185 Configuring the Bootloader 187 Configuring LILO 188 Configuring GRUB 192 Managing Linux Runlevels 203 How Runlevels Work 203 Managing Runlevels and init Scripts 206 Shutting Down the System 217 Chapter Review 218 Chapter 7 Managing the Graphical Accelerated Review 221 Questions 223 Answers 227 Environment 229 How the X Environment Works 230 Configuring the X Environment 235 Configuring the X Server 235 Configuring an X Font Server 245 Configuring a Display Manager 248 Trying Out Desktop Environments 248 Configuring a Display Manager 249 Configuring Accessibility 253 Keyboard Accessibility 254 Mouse Accessibility 256 Screen Readers 257

5 _ LPIC-1/CompTIA llnux+ Certification All-ln-One Exam Guide xviii Screen Magnifiers 257 Braille Devices 260 High-Contrast, Large-Text Themes 261 Chapter Review 263 Accelerated Review 266 Questions 270 Answers 273 Chapter 8 Managing Linux Software 275 Managing Software with RPM 276 Installing Software with RPM 276 Managing Installed Software with RPM 288 Using yum to Install RPM Packages 295 Installing Software from Source Code 298 Preparing the Installation Files 299 Compiling the Executable 301 Installing the Executable 302 Uninstalling Software Compiled from Source Code 303 Managing Debian Software Packages 304 Debian Package Naming 305 Installing Packages with dpkg 305 Viewing Package Information with apt-cache 308 Installing Packages with apt-get 310 Using aptitude 312 Managing Shared Libraries 313 How Shared Libraries Work 314 Managing Shared Library Dependencies 315 Chapter Review 318 Accelerated Review 320 Questions 322 Answers 327 Chapter 9 Managing Linux Users and Groups 329 Understanding Linux Users and Groups 331 Linux User Accounts 332 Linux Groups 347 Chapter Review 350 Accelerated Review 352 Questions 353 Answers 355 Chapter 10 Managing Linux File Systems 357 Managing Disk Partitions 357 Using fdisk to Manage Disk Partitions 358 Building a File System with mkfs 363 Understanding LVM 367

6 Contents xix Mounting a Partition with mount 368 Maintaining Linux File Systems 371 Mounting Removable Media 381 Working with Floppies 381 Working with Optical Devices 382 Working with USB and FireWire Devices 383 Backing Up Data 384 Selecting a Backup Medium 385 Selecting a Backup Strategy 386 Using Linux Backup Utilities 389 Chapter Review 394 Accelerated Review 396 Questions 398 Answers 401 Chapter I I Managing Ownership, Permissions, and Quotas 403 Managing Ownership 403 How Ownership Works 403 Managing Ownership from the Command Line 404 Managing File and Directory Permissions 407 How Permissions Work 407 Managing Permissions from the Command Line with chmod 409 Working with Default Permissions 413 Working with Special Permissions 415 Implementing Disk Quotas 417 Chapter Review 422 Accelerated Review 424 Questions 425 Answers 427 Chapter 12 Managing Hardware Under Linux 429 Managing PC Hardware 429 Identifying Mass Storage Devices 430 Working with Removable Hardware Interfaces 441 Managing System Resources 444 Managing Integrated Devices 449 Managing Systems Without External Peripherals 451 Working with Linux Drivers 451 What Exactly Is a Driver Anyway? 452 How Drivers Are Implemented Under Linux 454 Managing Kernel Modules 455 Working with Hotplug and Coldplug Devices 462 Chapter Review 463 Accelerated Review 466 Questions 469 Answers 473

7 LPIC-l/CompTIA Linux* Certification All-in-One Exam Guide XX Chapter 13 Managing Linux Processes 475 How Linux Handles Processes 475 What Exactly Is a Process? 476 The Heredity of Linux Processes 478 Managing Running Processes 482 Starting System Processes 482 Viewing Running Processes 484 Prioritizing Processes 489 Managing Foreground and Background Processes 491 Ending a Running Process 494 Keeping a Process Running After Logout 495 Scheduling Processes 498 Using the at Daemon 498 Using the cron Daemon 501 Chapter Review 506 Accelerated Review 509 Questions 512 Answers 515 Chapter 14 Writing Shell Scripts 517 Working with Shell Scripts 517 The Components of a Shell Script 517 How Shell Scripts Are Executed 518 Creating a Basic Script 520 Displaying Text on the Screen 520 Adding Commands to a Script 520 Reading Input from the User 521 Using Control Structures in Scripts 523 Using if/then Structures 523 Using case Structures 525 Using Looping Structures 527 Processing Text Streams 529 cut 530 expand and unexpand 530 fmt 531 join and paste 532 nl od pr 535 sed and awk sort split 539 tr uniq wc 541

8 Contents xxi Using Command Substitution and Shell Functions 542 Using Command Substitution 542 Using Shell Functions 543 Chapter Review 544 Accelerated Review 548 Questions 549 Answers 553 Chapter 15 Managing Linux Network Settings 555 IP Networking Overview 556 What Is a Protocol? 557 How IP Addresses Work 561 How the Subnet Mask Works 564 Specifying the DNS Server and Default Gateway Router Addresses 566 Configuring Network Addressing Parameters 568 Installing the Ethernet Board 569 Configuring IP Parameters 570 Configuring Routing Parameters 576 Configuring Name Resolver Settings 578 Troubleshooting Network Problems 581 Chapter Using a Standardized Troubleshooting Model 581 Using ping 583 Using netstat 585 Using traceroute 585 Using Name Resolution Tools 587 host 588 Review 589 Accelerated Review 592 Questions 594 Answers 598 Chapter 16 Managing Network Services on Linux 601 Configuring Printing with CUPS 602 How Linux Printing Works 602 Installing CUPS 604 Configuring CUPS 605 Using the Line Printer Daemon (lpd) 613 Troubleshooting Printing Issues 613 Maintaining System Time 616 Setting the Hardware Clock with hwclock 617 Synchronizing Time with netdate 618 Synchronizing Time with NTP 618 Managing an MTA 625 How Works 625 Using MTA Management Commands on Linux 629

9 LPIC-l/CompTIA Linux* Certification All-in-One Exam Guide xxii Managing SQL Data 632 How Databases Work 632 Installing MySQL 633 Managing Data in the SQL Server 635 Chapter Review 638 Accelerated Review 642 Questions 646 Answers 649 Chapter 17 Securing Linux 651 Secure the System 651 Securing the Physical Environment 651 Securing Access to the Operating System 653 Control User Access 655 To root Or Not to root? 655 Implementing a Strong Password Policy 659 Configuring User Limits 661 Disabling User Login 663 Auditing Files 665 Defending Against Network Attacks 668 Mitigating Network Vulnerabilities 668 Implementing a Firewall with iptables 672 Managing System Logs 679 Configuring Log Files 679 Using Log Files to Troubleshoot Problems 684 Using Log Files to Detect Intruders 686 Configuring xinetd and inetd 688 Configuring xinetd 689 Configuring inetd 692 Chapter Review 695 Accelerated Review 700 Questions 704 Answers 707 Chapter 18 Using Encryption 709 How Encryption Works 710 Symmetric Encryption 711 Asymmetric Encryption 712 Encrypting Remote Access with OpenSSH 715 How OpenSSH Works 715 Configuring OpenSSH 717 Tunneling Traffic Through SSH 721 Configuring SSH to Use Public Key Authentication 726 Encrypting Linux Files 730 How GPG Works 730 Using GPG to Encrypt Files 731

10 XXIII Chapter Review 737 Accelerated Review 742 Questions 745 Answers 748 Appendix A Exam Objective Reference 751 Exam LXO Exam LXO Appendix B About the CD 769 System Requirements 769 Accessing the MasterExam Practice Exams in Linux 769 Installing and Running MasterExam 770 MasterExam 770 Video Training Clips 771 PDF Copy of the Book 771 Help 771 Removing Installation(s) 771 Technical Support 771 LearnKey Technical Support 771 Index 773