CENT 305CENT 305Information Systems SecurityInformation Systems SecurityLinux Introduction

Open SUSE OSOpen SUSE OSA “distro” of the Linux OS, which is a “flavor” of Unix OS. A multiuser, multitask, both GUI and command-line interface OS

Graphical environments similar to Windows/Mac, with (free!) Open Source OfficeCommand line environment similar to Windows DOS and uhunix.hawaii.edu

Open source softwarePopular in European marketsPurchased recently by Novell

Now commercially available as enterprise operating systemSoftware is still open source --- i.e., the code is freely available for modification

OpenSUSE Linux versions 12 and 11Open source (free) version supported by SUSECan be downloaded and installed at home for no charge - also available in Live CD format. Gerald has copies of the Live CD for the KDE and Gnome environments.Comparable to Enterprise (Server) and Desktop versions combined

ReferencesOnline references will be posted on course web siteGetting Started with Linux; Novell's Guide to CompTIA's Linux+, Novell & Jason Eckert, Thomson Course Technology, 2007, ISBN-10: 1-4188-3730-X

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ObjectivesObjectivesFamiliarity with Linux interfaces

◦ Graphical User Interface◦ Command Line Interfaces

Be able to use basic Linux features◦ bash shell - command line interface◦ vi (command line) text editor◦ basic scripts

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Graphical User Interface Graphical User Interface (Demo)(Demo)

Login Screen◦ Menu options◦ Shutdown/restart

KDE desktop features◦ KDE control panel (Kicker)

KDE menu, Konqueror, Terminal Emulation◦ KDE menu◦ KDE Desktop

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Command Line InterfacesCommand Line InterfacesVirtual Terminals

◦ CTL-ALT-F#◦ Consoles F1-F6 are command line interfaces◦ Console F7 is the graphical interface◦ Each console is independent of the others

Terminal Windows (Konsole, and others)◦ Accessed as a shell window in the graphical interface.◦ Provides an emulation of a virtual console.

Important: Unix command syntax:command [-options] arguments◦ Example: ls –R mydir◦ Example: cp file1 file2

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Linux Help ResourcesLinux Help Resources man pages

◦ online reference manuals ◦ Syntax: man [-k] whatyouarelookingup◦ example: man ls◦ example: man –k backup◦ Uses the less pager for navigation (man less)

info pages◦ more sophisticated navigation than man pages

(info info) Release notes

◦ /usr/share/doc/release-notes How-to files (Linux Documentation Project)

◦ /usr/share/doc/howto/en/html or txt Package help files

◦ /usr/share/doc/packages/package-name

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YaST Management UtilityYaST Management UtilityYet Another Setup UtilityWorks with command line or graphical

environmentAllows management of

◦ Software packages◦ User & Group Accounts◦ Printer Configuration◦ View Hardware Configuration◦ X Windows configuration

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Command ShellsCommand Shells The command shell program provides the command line

interface in a non-graphical environment.◦ Accepts commands entered by the user on the

command line.◦ Runs the specified command and displays the result on

the screen.◦ Also called the command interpreter.

Linux supports a variety of shells:◦ bash - the Bourne Again SHell, default Linux shell◦ sh - the Bourne SH, the original UNIX shell◦ csh - the c shell (Open SUSE 11 uses tcsh)◦ ksh - the Korn shell◦ zsh - the z shell

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Using the Command LineUsing the Command LineStart a shell window (Konsole)Using commands --- previous examples...Pipes and redirection

◦ cat /etc/passwd | less (pipe)◦ cat /etc/passwd > mypasswd.txt (redirect, i.e. put

into)◦ cat /etc/group >> mypasswd.txt (append)

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Text EditorsText EditorsNeeded for editing Linux configuration files, which are

usually ASCII text files.Graphical text editors

◦ gedit, kwrite, kate, etc....◦ Work fine as long as there is a GUI...

Terminal based text editors◦ vi (and its improved version vim), emacs, pico◦ MUST be used in a command-line environment such as a

virtual console – why?

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Overview of Terminal Based Text Overview of Terminal Based Text EditorsEditors

vi or vim◦ Most commonly used by system administrators◦ Moderately complex and powerful tool.◦ Installed by default on ALL UNIX/Linux systems --- so it's always

available◦ Must know it, in case nothing else is available

emacs◦ Frequently used by programmers.◦ Very complex to learn and use and very powerful.◦ May NOT installed by default and is not always available.

pico◦ Simple, menu-driven text editor◦ Easy to learn and use.◦ Not very powerful.◦ May not always be installed, but usually is.

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vim introvim intro

vivisual editorcommonly used Unix text editor

vimvi improvedupdated version of vi that’s somewhat easier to usedefault version of vi provided with Linux

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vim basicsvim basics

vim filenamecreates and new file and opens it for editing

vi modescommand mode --- used for entering commands, saving files, and quitting viinsert mode --- used for entering text

Laulima includes a summary of vi commandsReview: type up a simple text file in vim and try different formatting.

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