LPI Linux Certification in a Nutshell

Description

Linux deployment continues to increase, and so does the demand for qualified and certified Linux system administrators. If you're seeking a job-based certification from the Linux Professional Institute (LPI), this updated guide will help you prepare for the technically challenging LPIC Level 1 Exams 101 and 102. The third edition of this book is a meticulously researched reference to these exams, written by trainers who work closely with LPI. You'll find an overview of each exam, a summary of the core skills you need, review questions and exercises, as well as a study guide, a practice test, and hints to help you focus. Major topics include: Critical GNU and Unix commands Linux installation and package management Devices and filesystems Text editing, processing, and printing The X Window System Networking and security Mail transfer agents Email, FTP, and web services These exams are for junior to mid-level Linux administrators with about two years of practical system administration experience. You should be comfortable with Linux at the command line and capable of performing simple tasks, including system installation and troubleshooting. Table of Contents Preface The Linux Professional Institute Audience for This Book Organization Book Chapters Conventions Used in This Book Using Code Examples How to Contact Us Safari® Books Online Acknowledgments Chapter 1. LPI Exams Chapter 2. Exam 101 Study Guide Exam Preparation Chapter 3. System Architecture (Topic 101.1) Objective 1: Determine and Configure Hardware Settings BIOS Date and time Disks and boot devices Using the /proc filesystem USB Topology USB Controllers USB Devices USB Drivers USB Hotplug Reporting Your Hardware lsmod Syntax Description Options lsdev Syntax Description lspci Syntax Description Options Manipulating Modules lsmod Syntax Description Example insmod Syntax Description Frequently used options Example rmmod Syntax Description Frequently used options Example modinfo Syntax Description Options Examples modprobe Syntax Description Frequently used options Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Device Management Definitions Chapter 4. Change Runlevels and Shut Down or Reboot System (Topics 101.2 and 101.3) Objective 2: Boot the System Boot-time Kernel Parameters Introduction to Kernel Module Configuration Kernel boot-time messages Reviewing system logs Objective 3: Change Runlevels and Shut Down or Reboot System Single-User Mode Overview of the /etc Directory Tree and the init Process Setting the Default Runlevel Determining Your System’s Runlevel Changing runlevels with init and telinit init Syntax Description Examples telinit System shutdown with shutdown Syntax Description Frequently used options Examples Chapter 5. Linux Installation and Package Management (Topic 102) Objective 1: Design a Hard Disk Layout System Considerations Limited disk space Larger systems Mount points Superblock MBR Booting from a USB device System role Backup Swap Space General Guidelines Objective 2: Install a Boot Manager LILO The boot loader The LILO map installer and its configuration file lilo Syntax Frequently used options LILO locations GRUB GRUB device naming Installing GRUB Booting GRUB The GRUB configuration file Objective 3: Manage Shared Libraries Shared Library Dependencies ldd Syntax Description Example Linking Shared Libraries ldconfig Syntax Description Frequently used options Example 1 Example 2 Example 3 Objective 4: Use Debian Package Management Debian Package Management Overview Managing Debian Packages dpkg Syntax Description Frequently used options Frequently used options Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 apt-get Syntax Description Frequently used options Frequently used commands Example dselect Syntax Description alien Syntax Description Frequently used options Example Objective 5: Use Red Hat Package Manager (RPM) RPM Overview Running rpm rpm Syntax Install/upgrade mode Frequently used install and upgrade options Example 1 Example 2 Uninstall mode Frequently used uninstall options Example Query mode Frequently used query package selection options Frequently used query information selection options Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Verify mode Frequently used verify options YUM Overview Checking installed packages Checking for updates Installing packages Removing packages Chapter 6. GNU and Unix Commands (Topic 103) Objective 1: Work on the Command Line The Interactive Shell Shell variable basics Entering commands at the command prompt Entering commands not in the PATH Entering multiple-line commands interactively Entering command sequences Command History and Editing Command substitution Applying commands recursively through a directory tree Manpages man Syntax Description Frequently used options Example 1 Example 2 Example 3 Manual sections Manpage format man mechanics Objective 2: Process Text Streams Using Filters cat Syntax Description Frequently used options Example cut Syntax Description Frequently used options Example expand Syntax Description Frequently used options fmt Syntax Description Frequently used options head Syntax Description Frequently used options join Syntax Description Frequently used options Example nl Syntax Description Frequently used options Example od Syntax Description Frequently used options Example paste Syntax Description Frequently used options Example 1 Example 2 Example 3 pr Syntax Description Frequently used options sort Syntax Description Frequently used options Example split Syntax Description Frequently used option Example tac Syntax Description Example tail Syntax Description Frequently used options tr Syntax Description Frequently used options Example 1 Example 2 Example 3 unexpand Syntax Description Frequently used options uniq Syntax Description Frequently used options Examples wc Syntax Description Frequently used options Example 1 Example 2 Objective 3: Perform Basic File Management Filesystem Objects Directories and files Inodes File and directory management commands bzip2 Syntax Description Frequently used options Example 1 Example 2 cp Syntax Description Frequently used options Example 1 Example 2 cpio Syntax Description Frequently used options Example 1 Example 2 dd Syntax Description Frequently used options Example 1 Example 2 file Syntax Description Frequently used options Example 1 Example 2 find Syntax Description Frequently used options Example 1 Example 2 Example 3 gzip and gunzip Syntax Description Frequently used options Example 1 Example 2 mkdir Syntax Description Frequently used options Examples mv Syntax Description Frequently used options rm Syntax Description Frequently used options rmdir Syntax Description Frequently used option touch Syntax Description Frequently used options File-Naming Wildcards (File Globbing) Objective 4: Use Streams, Pipes, and Redirects Standard I/O and Default File Descriptors Pipes Redirection Using the tee Command tee Syntax Description Option Example The xargs Command xargs Syntax Description Frequently used options Example Objective 5: Create, Monitor, and Kill Processes Processes Process Monitoring ps Syntax Description Frequently used options Examples pstree Syntax Description Frequently used options Example top Syntax Description Popular command-line options Frequently used interactive options Example 1 Example 2 Example 3 free Syntax Description Frequently used options Example uptime Syntax Description Examples Signaling Active Processes kill Syntax Description Examples Terminating Processes Shell Job Control bg Syntax Description fg Syntax Description jobs Syntax Description Frequently used option nohup Syntax Description Example 1 Objective 6: Modify Process Execution Priorities nice nice Syntax Description Example 1 Example 2 Changing nice numbers on running processes renice Syntax Description Frequently used options Examples Objective 7: Search Text Files Using Regular Expressions Regular Expression Syntax Using grep grep Syntax Description Frequently used options Examples Using sed sed Syntax Description Frequently used options Addressing Commands Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Examples Anchors Description Example 1 Example 2 Groups and ranges Description Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Modifiers Description Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Basic regular expression patterns Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Using regular expressions as addresses in sed Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Objective 8: Perform Basic File Editing Operations Using vi Invoking vi vi Basics Chapter 7. Devices, Linux Filesystems, and the Filesystem Hierarchy Standard (Topic 104) Objective 1: Create Partitions and Filesystems Disk Drives Under Linux Hard disk devices Disk partitions The root filesystem and mount points Managing partitions fdisk Syntax Description Frequently used commands Example 1 Example 2 Creating filesystems mkfs Syntax Description Frequently used options Example 1 Example 2 Creating swap partitions mkswap Syntax Description Example Objective 2: Maintain the Integrity of Filesystems Monitoring Free Disk Space and Inodes df Syntax Description Frequently used options Example 1 Example 2 Example 3 Monitoring Disk Usage du Syntax Description Frequently used options Example 1 Example 2 Example 3 Example 4 Example 5 Modifying a Filesystem tune2fs Syntax Description Frequently used options Example 1 Example 2 xfs_info Syntax Description Examples Checking and Repairing Filesystems fsck Syntax Description Frequently used options for fsck Frequently used options for e2fsck Example 1 Example 2 Example 3 Example 4 xfs_metadump Syntax Description Frequently used options Objective 3: Control Filesystem Mounting and Unmounting Managing the Filesystem Table Mounting Filesystems mount Syntax Description Command-line options Mount options Filesystem types Example 1 Example 2 Example 3 Example 4 Unmounting Filesystems umount Syntax Description Example 1 Example 2 Objective 4: Set and View Disk Quotas Quota Limits Quota Commands quota Syntax Description Frequently used options Example 1 Example 2 quotaon Syntax Description Frequently used options Example 1 Example 2 quotaoff Syntax Description Frequently used options Example quotacheck Syntax Description Frequently used options Example 1 Example 2 edquota Syntax Description Frequently used options Example 1 Example 2 repquota Syntax Description Frequently used options Example Enabling Quotas Objective 5: Manage File Permissions and Ownership Linux Access Control The mode bits The mode string Setting Access Modes New files Changing access modes chmod Syntax Description Frequently used options Example 1 Example 2 Example 3 Example 4 chown Syntax Description Frequently used options Example 1 Example 2 chgrp Syntax Description Example 1 Setting Up a Workgroup Directory Objective 6: Create and Change Hard and Symbolic Links Why Links? ln Syntax Description Frequently used options Example 1 Example 2 Preserving links Finding links to a file Objective 7: Find System Files and Place Files in the Correct Location Datatypes The root Filesystem The /usr filesystem The /var filesystem Linux annex Where’s that binary? Locating Files which Syntax Description Example find Syntax Description Example locate Syntax Description Example updatedb Syntax Description Option Example Additional options whereis Syntax Description Example type Syntax Description Example Chapter 8. Exam 101 Review Questions and Exercises System Architecture (Topic 101) Review Questions Exercises Linux Installation and Package Management (Topic 102) Review Questions Exercises GNU and Unix Commands (Topic 103) Review Questions Exercises Devices, Linux Filesystems, and the Filesystem Hierarchy Standard (Topic 104) Review Questions Exercises Chapter 9. Exam 101 Practice Test Questions Answers Chapter 10. Exam 101 Highlighter’s Index System Architecture Objective 101.1: Determine and Configure Hardware Settings PC BIOS Resource assignments Objective 101.2: Boot the System Boot order Information Objective 101.3: Change Runlevels and Shut Down or Reboot System Runlevels Linux Installation and Package Management Objective 102.1: Design Hard Disk Layout /proc Objective 102.2: Install a Boot Manager LILO GRUB Objective 102.3: Manage Shared Libraries Concepts Commands Objective 102.4: Use Debian Package Management Commands Objective 102.5: Use Red Hat Package Manager (RPM) Concepts GNU and Unix Commands Objective 103.1: Work on the Command Line The interactive shell and shell variables Entering commands Command history, editing, and substitution Recursive execution Objective 103.2: Process Text Streams Using Filters The commands The stream editor, sed Objective 103.3: Perform Basic File Management Concepts File and directory management commands File-naming wildcards Objective 103.4: Use Streams, Pipes, and Redirects Concepts Standard I/O Pipes and redirection Objective 103.5: Create, Monitor, and Kill Processes Concepts Monitoring commands Signaling processes Shell job control Objective 103.6: Modify Process Execution Priorities Concepts Commands Objective 103.7: Search Text Files Using Regular Expressions Concepts Position anchors Character sets Modifiers Commands Objective 103.8: Perform Basic File Editing Operations Using vi Subcommands Devices, Linux Filesystems, and the Filesystem Hierarchy Standard Objective 104.1: Create Partitions and Filesystems Disk drives and partitions Filesystems The root filesystem and mount points Partition and filesystem management commands Objective 104.2: Maintain the Integrity of Filesystems Filesystem commands Objective 104.3: Control Filesystem Mounting and Unmounting Managing the filesystem table Mounting and unmounting Filesystem types Objective 104.4: Set and View Disk Quotas Quota types Commands Objective 104.5: Manage File Permissions and Ownership Access control Setting access modes Commands for file ownership Objective 104.6: Create and Change Hard and Symbolic Links Concepts ln Objective 104.7: Find System Files and Place Files in the Correct Location File Hierarchy Standard (FHS) The directory hierarchy Locating files Chapter 11. Exam 102 Overview Chapter 12. Exam 102 Study Guide Exam Preparation Chapter 13. Shells, Scripting, and Data Management (Topic 105) Objective 1: Customize and Use the Shell Environment An Overview of Shells The Bash Shell Shells and environment variables Aliases Functions Configuration files .inputrc Objective 2: Customize or Write Simple Scripts Script Files Creating a simple bash script Executable files Shebang! The shell script’s environment Location, ownership, and permissions SUID and SGID rights Basic Bash Scripts Return values File tests Command substitution Mailing from scripts Abbreviated bash command reference break Syntax Description case Syntax Description continue Syntax Description echo Syntax Description Frequently used options Useful special characters exit Syntax Description Example for Syntax Description Example function Syntax Description Example getopts Syntax Description if Syntax Description kill Syntax Description Options read Syntax Description Example return Syntax Description seq Syntax Description Frequently used options Example shift Syntax Description source Syntax Description test Syntax Description Frequently used options Example until Syntax Description while Syntax Description Example Objective 3: SQL Data Management Accessing a MySQL Server Database Overview Aggregate Functions Multitable Queries Chapter 14. The X Window System (Topic 106) An Overview of X Objective 1: Install and Configure X11 Selecting and Configuring an X Server Supported video hardware Installing X.Org Configuring an X server and the xorg.conf file Distribution-specific tools X Fonts Installing fonts The X font server Controlling X Applications with .Xresources Objective 2: Set Up a Display Manager Configuring xdm Running xdm manually Running xdm automatically Basic xdm customization X Terminals xdm for X terminals Configuring KDM Configuring GDM Switching display managers Objective 3: Accessibility Chapter 15. Administrative Tasks (Topic 107) Objective 1: Manage User and Group Accounts and Related System Files User Accounts and the Password File Groups and the Group File The Shadow Password and Shadow Group Systems Group passwords and shadow groups User and Group Management Commands useradd Syntax Description Frequently used options Example usermod Syntax Description Frequently used options Examples userdel Syntax Description Example groupadd Syntax Description groupmod Syntax Description Option groupdel Syntax Description passwd Syntax Description Option gpasswd Syntax Description Objective 2: Automate System Administration Tasks by Scheduling Jobs Using cron User crontab files crontab Syntax Description Frequently used options Example System crontab files Using at at Syntax Description Frequently used options Example1 Example2 Controlling User Access to cron and at Objective 3: Localization and Internationalization Chapter 16. Essential System Services (Topics 108.1 and 108.2) Objective 1: Maintain System Time NTP Concepts The NTP Software Package Components ntpd Syntax Description Frequently used options Example ntpdate Syntax Description Frequently used options Example ntpq Syntax Description Frequently used options Example ntpdc Syntax Description ntptrace Syntax Description Frequently used options Examples The Hardware Clock hwclock Syntax Description Examples Time Zones Objective 2: System Logging Configuring syslogd Client/Server Logging Logfile Rotation Examining Logfiles Chapter 17. Mail Transfer Agent (MTA) Basics (Topic 108.3) Objective 3: Mail Transfer Agent (MTA) Basics Configuration of Sendmail mail Syntax Description Example Mail queuing Description mailq Syntax Description Example Configuration of Postfix Configuration of Qmail Configuration of Exim Chapter 18. Manage Printers and Printing (Topic 108.4) Objective 4: Manage Printers and Printing An Overview of Printing BSD and System V Interfaces LPRng CUPS CUPS printing overview CUPS backends CUPS filters Managing CUPS print queues lp Syntax Description Options Example 1 Example 2 Example 3 cancel Syntax Description Options lpstat Syntax Description Options lpadmin Syntax Description Options lpq Syntax Description Options Example 1 Example 2 Example 3 Example 4 lprm Syntax Description Example 1 Example 2 lpr Syntax Description Frequently used options Example 1 Example 2 Example 3 Troubleshooting General Printing Problems The Error Logfile The Page Logfile The Access Logfile Using the cups-config Utility for Debugging Chapter 19. Networking Fundamentals (Topic 109.1) Objective 1: Fundamentals of Internet Protocols Network Addressing Private IP addresses and NAT Classless Inter-Domain Routing (CIDR) Internet Protocol Version 6 (IPv6) Masks Protocols Services Utilities dig Syntax Description Example ftp Syntax Description Frequently used options Frequently used commands Example 1 Example 2 ping Syntax Description Frequently used options Example telnet Syntax Description traceroute Syntax Description whois Syntax Description Example Chapter 20. Basic Network Configuration (Topics 109.2 and 109.4) Objective 2: Basic Network Configuration and Objective 4: Configuring Client Side DNS Network Interfaces Configuration files Configuration commands ifconfig Syntax Description Frequently used parameters Example 1 Example 2 Example 3 ping Syntax Description route Syntax Description Frequently used options and keywords Example 1 Example 2 Example 3 DHCP Subnets and relays Leases dhcpd dhcpd Syntax Description Frequently used options A Standard Linux Network Configuration Chapter 21. Basic Network Troubleshooting (Topic 109.3) Objective 3: Basic Network Troubleshooting ping Syntax Description host Syntax Description Frequently used options Example 1 Example 2 traceroute Syntax Description Frequently used options Example netstat Syntax Description Frequently used options Examples Common Manual Network Interface Tasks dig Chapter 22. Security (Topic 110.1) Objective 1: Perform Security Administration Tasks The (In)Security of SUID su Syntax Description Frequently used options Examples sudo Syntax Description Frequently used options Example 1 Example 2 Example 3 User IDs and Passwords usermod Syntax Description Frequently used options Shadow Passwords chage Syntax Description Frequently used options Examples Setting Limits on Users ulimit Syntax Description Frequently used options Example Querying System Services netstat Description Examples nmap Syntax Description Frequently used options Example 1 Example 2 Example 3 lsof Syntax Description Frequently used options Example 1 Example 2 Chapter 23. Set Up Host Security (Topic 110.2) Objective 2: Set Up Host Security The Super-Server inetd syntax xinetd Security with TCP_WRAPPERS Configuration Chapter 24. Securing Data with Encryption (Topic 110.3) Objective 3: Securing Data With Encryption Using Secure Shell (SSH) Installation and Configuration Example /etc/ssh/sshd_config file DSA and RSA Overview Generating and Using Keys Enabling bulk logins on multiple hosts for multiple users Using the RSA algorithm ssh-keygen Syntax Description Example The Server Public and Private Key ssh-agent Other SSH Tricks SSH Port Forwarding ssh -R|L Syntax Description Example Configuring OpenSSH Configuring and Using GNU Privacy Guard (GPG) Generating a Key Pair Importing a Public Key to a GPG Keyring Signing Keys Listing Keys Export both a Public and Private Key Encrypting a File Troubleshooting Files in the ~/.gnupg/ Directory Chapter 25. Exam 102 Review Questions and Exercises Shells, Scripting, and Data Management (Topic 105) Review Questions Exercises The X Window System (Topic 106) Review questions Exercises Administrative Tasks (Topic 107) Review questions Exercises Essential System Services (Topic 108) Review Questions Exercises Networking Fundamentals (Topic 109) Review Questions Exercises Security (Topic 110) Review Questions Exercises Chapter 26. Exam 102 Practice Test Questions Answers Chapter 27. Exam 102 Highlighter’s Index Shells, Scripting, and Data Management Objective 105.1: Customize and Use the Shell Environment Bash Objective 105.2: Customize or Write Simple Scripts Environment Objective 105.3: SQL Data Management The X Window System Objective 106.1: Install and Configure X11 Objective 106.2: Set Up a Display Manager Objective 106.3: Accessibility Administrative Tasks Objective 107.1: Manage User and Group Accounts and Related System Files passwd and group Shadow files User and group management commands Objective 107.2: Automate System Administration Tasks by Scheduling Jobs Using cron Using at User access Objective 107.3: Localization and Internationalization Essential System Services Objective 108.1: Maintain System Time Objective 108.2: System Logging Syslog Logfile rotation Examining logfiles Objective 108.3: Mail Transfer Agent (MTA) Basics Objective 108.4: Manage Printers and Printing CUPS Legacy printing (lpd) /etc/printcap Networking Fundamentals Objective 109.1: Fundamentals of Internet Protocols Addressing and masks Protocols TCP/IP services TCP/IP utilities Objective 109.2: Basic Network Configuration Objective 109.3: Basic Network Troubleshooting Objective 109.4: Configuring Client Side DNS Security Objective 110.1: Perform Security Administration Tasks Objective 110.2: Set Up Host Security TCP wrappers Shadow passwords Objective 110.3: Securing Data with Encryption Index