Chapter 1: Introducing Linux The Complete Guide To Linux System Administration

The Complete Guide to Linux System Administration2 Objectives Describe how Linux was created and how it compares to other operating systems List versions of Linux currently available Outline the skills required and challenges facing a system administrator Log in and begin using a Linux system

The Complete Guide to Linux System Administration3 Objectives (continued) Explore a Linux file system from the command line Locate additional information about commands you want to use or learn about

The Complete Guide to Linux System Administration4 A Brief History Popular graphical computers –Apple Macintosh –Microsoft Windows Linux –Alternative for people whose computing needs require something different

The Complete Guide to Linux System Administration5 Understanding Operating Systems Software –Collection of instructions that control the tasks a computer performs –Can be changed without disassembling the computer and rewiring Operating system –Software that helps other programs control computer hardware and interact with users

The Complete Guide to Linux System Administration6 Understanding Operating Systems (continued) Application –Software program that provides service for computer user –Cannot act without “permission” from operating system

The Complete Guide to Linux System Administration7 Operating System Functions Initialize computer hardware Allocate system resources to programs Keep track of multiple programs running at same time Provide organized method for all programs to use system devices

The Complete Guide to Linux System Administration8 Operating System Functions (continued) Major operating system components: –Kernel –Device drivers –Shell –Utility programs –Graphical user interface (GUI)

The Complete Guide to Linux System Administration9 The UNIX Operating System UNIX –Operating system –Originally created at AT&T Bell Labs in early 1970s –Designed to control networked computers that were shared by many users –Features and low cost of Linux effectively driving UNIX out of market

The Complete Guide to Linux System Administration10 The Free Software Foundation and the GNU Project Free software foundation (FSF) –Software itself should not be restricted in distribution by standard commercial license agreement GNU project –Completely free version of UNIX –Written from scratch

The Complete Guide to Linux System Administration11 The Free Software Foundation and the GNU Project (continued) Software license –Legal definition of who can use software and how it can be used GNU general public license (GPL) –Very different from standard commercial software license –Author agrees to give away source code –Anyone is licensed to redistribute it in any form

The Complete Guide to Linux System Administration12 The Free Software Foundation and the GNU Project (continued) GNU GPL –Any modifications to the source code must be licensed under the GPL –Sometimes called copyleft –OpenSource Refers to software licensed under GPL Public domain –No one has copyright to software –Not same as GPL

The Complete Guide to Linux System Administration13 Linux Arrives Linus Torvalds –Decided to create UNIX-like operating system kernel for IBM-compatible PC –Solicited help via Internet –Released Linux kernel under GPL Linux development method –Person identifies need and begins writing program –Developer announces project on Internet

The Complete Guide to Linux System Administration14 Linux Arrives (continued) Linux development method (continued) –Others respond and work on different parts of project –Person leading project releases software –People download source code and try program; send back information about problems –Developers fix bugs Forking –Creating new project based on existing source code

The Complete Guide to Linux System Administration15 Motivating Free Software Developers Why would so many people devote so much effort to something without expecting any reward? –Fills developer’s specific technical need –Respect of like-minded professionals –Sense of contribution and community –Valuable boost to developer’s resume

The Complete Guide to Linux System Administration16 The Strengths Of Linux Stability Security Speed Cost Multiprocessing and other high-end features Applications

The Complete Guide to Linux System Administration17 Linux In The Market Linux is packaged and sold Red hat software –Current market leader

The Complete Guide to Linux System Administration18 Linux Distributions Linux distribution –Productized version of Linux Includes operating system kernel along with other components System utilities –Related to managing Linux system Price –Generally between $2 and $100

The Complete Guide to Linux System Administration19 Linux Distributions (continued)

The Complete Guide to Linux System Administration20 Red Hat Software Fedora distribution –Free product Red Hat Enterprise Linux configurations –WS (workstation) –ES (enterprise server) –AS (application server) Red Hat Enterprise Linux –Sold as subscription service

The Complete Guide to Linux System Administration21 Red Hat Software (continued) Red Hat Enterprise Linux –Updates from Red Hat Network (RHN) Red Hat –Excels in service and support offered to large companies using Linux

The Complete Guide to Linux System Administration22 Hardware Requirements Can run on very minimal hardware Recommend that computer have minimum of: –1 GB of free disk space –64 MB of RAM For Red Hat Enterprise Linux installations: –256 MB of RAM –300 MHZ CPU –800 MB of free disk space

The Complete Guide to Linux System Administration23 Version Numbering Version numbers assigned to: –Each release of Linux kernel –Each component of Linux distribution –Linux distributions Most users select latest available version

The Complete Guide to Linux System Administration24 Version Numbering (continued) Kernel version number components –Major version number –Minor version number Even indicates production release Odd indicates development release –Patch-level number

The Complete Guide to Linux System Administration25 Linux Certification Industry certification programs –Red Hat Certified Technician –Red Hat Certified Engineer –LPI Certification –Linux Certified Administrator (LCA) Certification –Linux+ Certification –Novell Certified Linux Engineer

The Complete Guide to Linux System Administration26 Linux Certification (continued) Red Hat’s certification program –Very highly regarded –Training program consists of three courses

The Complete Guide to Linux System Administration27 The Work of a System Administrator Linux is increasingly part of information technology infrastructure of large organizations Knowledge of Linux can set you on path to a fulfilling and profitable career

The Complete Guide to Linux System Administration28 Careers in Linux System administrator Network administrator Software engineer Trainer Technical writer Product marketing Business consultant

The Complete Guide to Linux System Administration29 The Duties of a System Administrator Role –Make technology work and continue to work for those who do “real work” of organization –Enable others to use technology benefits Responsibilities –Create new user accounts –Maintain system hardware –Train end users

The Complete Guide to Linux System Administration30 The Duties of a System Administrator (continued) Responsibilities –Keep system running smoothly –Document system –Define procedures and policies –Recover from emergencies –Plan systems

The Complete Guide to Linux System Administration31 Ethics, Privacy, and the Law Working as system administrator involves many ethical issues Fellow employees count on your work to do theirs Best route to success comes through making employer successful System administrators guild (SAGE) –

The Complete Guide to Linux System Administration32 Starting To Use Linux Should have access to computer with Linux installed

The Complete Guide to Linux System Administration33 Logging In Log in –Identify yourself to operating system so that it knows: You are authorized to use system Which parts of system to permit you to access User account –Set of permissions to use system –Has associated user name and password

The Complete Guide to Linux System Administration34 Logging In (continued) Modes –Graphical –Text

The Complete Guide to Linux System Administration35 Graphical Environments Popular desktops –KDE desktop –GNOME desktop Features –Taskbar –Main menu –Desktop icons –Multiple overlapping windows

The Complete Guide to Linux System Administration36 Opening a Terminal Window Terminal window –Resembles console –Enter commands from keyboard

The Complete Guide to Linux System Administration37 Exploring the File System

The Complete Guide to Linux System Administration38 File System Concepts Files are organized into directories Names are case sensitive Names can be long Names may contain many different types of characters Can include file extensions –Not required

The Complete Guide to Linux System Administration39 File System Concepts (continued) Directory relationships –Parent directory –Subdirectory Path –List of directories –Absolute path –Relative path Linux does not have separate drives

The Complete Guide to Linux System Administration40 File System Concepts (continued) Root directory –Parent of all directories –/ /Usr subdirectory –Contains the greatest number of files and subdirectories on newly installed systems

The Complete Guide to Linux System Administration41 Managing Files With Graphical Utilities File manager –Displays contents of a directory as collection of icons or file names –Manage files and directories –Choose Browse Filesystem on main menu Home directory –Subdirectory where all personal files are stored

The Complete Guide to Linux System Administration42 Working at a Command Line Linux system administrators should be very comfortable working at command line –Much faster way to perform most tasks –Some tasks cannot be use graphical interface Commands –pwd  mv  slocate –cd  ls  file –mkdir  cat  cp –rmdir  touch

The Complete Guide to Linux System Administration43 Working at a Command Line (continued) Command-line prompt consists of: –User name –Name of computer at which you are working –Last directory name in current working directory –$ character

The Complete Guide to Linux System Administration44 Working at a Command Line (continued) Parameters –Define what command will operate on Options –Alter how command operates Timestamp –Information about date and time when event occurred

The Complete Guide to Linux System Administration45 Finding Command Help Learn more details Explore additional Linux topics

The Complete Guide to Linux System Administration46 Reading Linux Documentation Linux documentation project (LDP) –HOWTOS Linux on the internet – Documentation included with software packages –Software packages provide some documentation –/Usr/doc –/Usr/share/doc

The Complete Guide to Linux System Administration47 Linux Command Information Man pages –Online manual pages –Man command Info page –Definitive source of information –Info command

The Complete Guide to Linux System Administration48 Summary Operating system –Provides interface between computer hardware and applications run by user Linux offers important features, such as: –Stability –Speed –Security –Flexibility –Low cost

The Complete Guide to Linux System Administration49 Summary (continued) Several Linux certification programs are available Several versions of Red Hat Enterprise Linux Most users rely on GUI to log in and use Linux –Text-only mode also available Information in Linux is stored in directories –Begins with root directory /

The Complete Guide to Linux System Administration50 Summary (continued) Linux files can include file extensions –Few Linux programs rely on file extensions to define what file contains Information about Linux is available online –Part of LDP