Contents at a Glance Introduction...1 Part I: Becoming Familiar with Enterprise Linux...7 Chapter 1: Getting Acquainted with Enterprise Linux...9 Chapter 2: Exploring the Desktop...17 Chapter 3: Putting Your System to Work...41 Chapter 4: Exploring the File System and Command Shell...61 Part II: Configuring Your Enterprise Linux Local Area Network...83 Chapter 5: Configuring and Managing the X Window System...85 Chapter 6: Configuring and Managing Printers...97 Chapter 7: Configuring the Network...109 Chapter 8: The Network File System...123 Chapter 9: Connecting to Windows PCs Using Samba...131 Part III: Securing Your Enterprise Linux System...141 Chapter 10: Security Basics...143 Chapter 11: Intrusion Detection and Prevention...161 Part IV: Configuring Your Enterprise Linux Internet Services...179 Chapter 12: Configuring and Managing DNS Servers...181 Chapter 13: Configuring and Managing an E-Mail Server...203 Chapter 14: Configuring and Managing an FTP Server...221 Chapter 15: Serving Web Pages...235 COPYRIGHTED MATERIAL Part V: Maintaining Your Enterprise Linux System...251 Chapter 16: Maintaining Your System with the Red Hat Network...253 Chapter 17: Administering Users and Groups...267 Chapter 18: Installing and Upgrading Software Packages...279 Chapter 19: Backing Up and Restoring Your Files...287
Part VI: The Part of Tens...311 Chapter 20: Ten Tips for Optimizing Your System...313 Chapter 21: Ten Troubleshooting and Problem-Solving Tips...329 Part VII: Appendixes...339 Appendix A: Installing Red Hat Enterprise Linux...341 Appendix B: What s on the CD-ROM?...361 Index...369
Table of Contents Introduction...1 About This Book...1 How This Book Is Organized...2 Part I: Becoming Familiar with Enterprise Linux...2 Part II: Configuring Your Enterprise Linux Local Area Network...3 Part III: Securing Your Enterprise Linux System...3 Part IV: Configuring Your Enterprise Linux Internet Services...3 Part V: Maintaining Your Enterprise Linux System...4 Part VI: The Part of Tens...4 Part VII: Appendixes...4 Icons Used in This Book...5 Typographical Roadsigns...5 Part I: Becoming Familiar with Enterprise Linux...7 Chapter 1: Getting Acquainted with Enterprise Linux...............9 Exploring the History of Enterprise Linux...9 Examining the Versions of Red Hat Enterprise...10 Red Hat Enterprise AS...11 Red Hat Enterprise ES...11 Red Hat Enterprise WS...12 Red Hat Desktop...12 Putting Enterprise Linux to Work...13 Configuring your local network...13 Using Enterprise Linux to maintain your system...14 Securing your system...14 Providing Internet services...15 Chapter 2: Exploring the Desktop...............................17 Examining the Graphical Login Screen...17 Logging In and Using the GNOME Desktop...19 Playing with the panel...20 Managing applets on the panel...21 Choosing applications from the Applications menu...22 Choosing actions from the Actions menu...24 Using the Nautilus File Manager...25 Displaying your home folder...27 Displaying the contents of a folder...27 Opening files...27 Accessing FTP sites...28
x Red Hat Enterprise Linux 4 For Dummies Using bookmarks...28 Managing your files and folders...29 Customizing the Nautilus File Manager...30 Editing File Manager preferences...31 Changing the File Manager background and icon emblems...32 Showing and hiding views...33 Configuring GNOME...33 Logging Out...34 Taking a Look at KDE...34 Managing applets...36 Choosing applications from the Applications menu...37 Using the Konqueror File Manager...39 Logging out...40 Chapter 3: Putting Your System to Work..........................41 Getting Started...41 Browsing the Web...42 Changing Browser Preferences...44 Sending and Receiving E-mail...45 Receiving e-mail...48 Sending e-mail...48 Working at the Office...49 Writing with OpenOffice.org Writer...50 Calculating with OpenOffice.org Calc...52 Impressing with OpenOffice.org Impress...53 Configuring OpenOffice.org...54 Keeping Yourself Entertained...55 Configuring your sound card...55 Playing audio files...56 Playing video files...57 Working with Images...58 Chapter 4: Exploring the File System and Command Shell..........61 Examining the Enterprise Linux File System Structure...61 Commanding the Shell...64 Opening a terminal window...64 Shell command syntax...66 Frequently Used Shell Commands...68 Getting help...68 Working with files and directories...69 Gaining superuser (root) privileges...78 Changing your system path...78 Mounting and unmounting drives...79 Viewing and stopping processes...80 Checking disk space...80 Creating an alias...81 Writing Shell Scripts...82
Table of Contents xi Part II: Configuring Your Enterprise Linux Local Area Network...83 Chapter 5: Configuring and Managing the X Window System.......85 Introducing the X Server...85 Configuring the X Server with the X Configuration Tool...86 Changing the display resolution...86 Changing the display color depth...87 Changing monitor type settings...88 Changing your video card type...89 Configuring dual monitors...90 Manually Configuring Your X Server from the X Configuration File...91 Device...91 Direct Rendering Infrastructure...92 Files...92 InputDevice...93 Module...93 Monitor...93 Screen...94 Restarting Your X Server...95 Disabling the X Server...95 Chapter 6: Configuring and Managing Printers...................97 Starting the Printer Configuration Tool...98 Configuring the print queue...100 Selecting the print driver...104 Editing the Printer Configuration...105 Deleting a printer...107 Setting the default printer...107 Chapter 7: Configuring the Network...........................109 The Enterprise Linux Network Configuration Tool...109 Adding an Ethernet device...110 Adding a wireless NIC...113 Adding a modem connection...115 Editing Your Network Configuration...117 Removing a NIC...117 Changing the NIC configuration...118 Managing DNS settings...119 Managing hosts...120 Working with profiles...120 Chapter 8: The Network File System...........................123 Configuring and Managing an NFS Server...123 Adding Shares to Export...124 Editing and Deleting NFS Exported Shares...127
xii Red Hat Enterprise Linux 4 For Dummies Command Line Configuration...128 Configuring an NFS Client...129 Mounting an NFS directory...129 Mounting NFS directories automatically at system start...129 Chapter 9: Connecting to Windows PCs Using Samba............131 Installing Samba...131 Configuring the Samba Server...132 Global...134 Homes...135 Printers...135 Creating Samba Users...136 Starting the Samba Server...136 Connecting to the Samba Server...137 Connecting to a Samba Client...138 Part III: Securing Your Enterprise Linux System...141 Chapter 10: Security Basics...................................143 Developing a Security Policy...143 Physical security...144 Document security...144 Network security...145 Consequences for breaking security policy...145 Responsibility...146 Performing a security audit...146 Implementing Host Security...147 System administrator security functions...147 Keeping your system updated...152 Implementing Network Security...152 Defining Internet services...152 Disabling standalone servers...153 Stopping services...155 Disabling xinetd server services...155 Building a Firewall...156 Configuring a simple firewall with the Security Level Configuration tool...157 Configuring a simple firewall with the iptables command...158 Chapter 11: Intrusion Detection and Prevention.................161 Discovering the Types of Intrusion Detection...161 Active detection...162 Passive detection...162 Using Software Detection Tools to Test Your System Security...163 Scanning your network with nmap...163 Using Tripwire to detect system changes...171
Table of Contents xiii Part IV: Configuring Your Enterprise Linux Internet Services...179 Chapter 12: Configuring and Managing DNS Servers.............181 Translating Web Names to IP Addresses...181 Types of DNS Servers...183 Examining the DNS Server Configuration Files...183 The named.conf file...185 Zone files...193 Configuring a Caching DNS Server...195 Configuring a Secondary Master DNS Server...196 Configuring a Primary Master Server...197 Checking Your Configuration...199 The host program...199 The dig program...199 Chapter 13: Configuring and Managing an E-Mail Server.........203 How E-Mail Works...203 Mail User Agent (MUA)...204 The Ximian Evolution e-mail client...204 Mail Transfer Agent (MTA)...209 Local Delivery Agent (LDA)...209 Introducing SMTP...210 The Post Office Protocol (POP3)...210 The Internet Mail Access Protocol (IMAP4)...211 Using Sendmail...211 Checking that Sendmail is installed and running...211 Configuring Sendmail...212 The m4 macro processor...213 Managing the mail queue...214 Configuring POP3...215 Configuring IMAP4...216 Setting up aliases to make life easier...216 Maintaining E-Mail Security...217 Protecting against eavesdropping...218 Using encryption...218 Using a firewall...218 Don t get bombed, spammed, or spoofed...218 Some SMTP cautions...219 Chapter 14: Configuring and Managing an FTP Server............221 Installing an FTP Server...221 Configuring an FTP Server...222 Configuring the /etc/vsftpd/vsftpd.conf file...223 Configuring the /etc/vsftpd.ftpusers file...227 Configuring the /etc/vsftpd.user_list file...228
xiv Red Hat Enterprise Linux 4 For Dummies Starting the FTP Server...228 Testing the FTP Server...229 Logging In to FTP Servers...229 Using gftp for FTP access...230 Accessing an FTP server with the command line FTP client...232 Chapter 15: Serving Web Pages...............................235 Installing and Starting the Web Server...235 Configuring and Managing Your Web Server...238 Editing the Apache Configuration File Using the HTTP Configuration Tool...239 Main tab...240 Virtual Hosts tab...240 Server tab...248 Performance Tuning tab...249 Saving Your Settings and Restarting the Web Server...250 Part V: Maintaining Your Enterprise Linux System...251 Chapter 16: Maintaining Your System with the Red Hat Network....................................253 Registering Your System...253 Configuring the Up2date Agent...256 Using the Red Hat Enterprise Linux Up2date Agent...259 Accessing the Red Hat Network with a Web Browser...262 Chapter 17: Administering Users and Groups...................267 Working with Users and Groups...267 Adding a new user...269 Adding a new group...270 Changing user properties...271 Changing group properties...272 Removing a user...273 Restricting Disk Usage with Quotas...274 Configuring disk quotas...274 Obtaining disk quota statistics...277 Chapter 18: Installing and Upgrading Software Packages........279 Managing Packages with the Red Hat Package Manager...279 Installing system packages...280 Removing system packages...282 Managing Applications from Binary rpm Files...282 Installing binary rpm files...283 Finding installed package files...284 Removing installed packages...285 Installing Applications from Compressed Zip Files...285
Table of Contents xv Chapter 19: Backing Up and Restoring Your Files................287 Planning Your Backup Strategy...287 Don t: Back up temp and cache files...287 Maybe: Back up OS files...288 Do: Back up database files and user files...288 Selecting Your Backup Media...289 Determining Your Backup Method...289 Enterprise Linux Backup Tools...292 Command line tools...292 Advanced tools...300 Part VI: The Part of Tens...311 Chapter 20: Ten Tips for Optimizing Your System................313 Optimizing the X Window System...313 Optimizing NFS...315 Optimizing Samba...316 Optimizing DNS...317 Optimizing Sendmail...318 Optimizing FTP...320 Optimizing Your Web Server...320 Building a Custom Kernel...321 Shutting Down Unused Services...322 Administering Your System by Using Webmin...325 Chapter 21: Ten Troubleshooting and Problem-Solving Tips.......329 Unable to Log In...329 Resetting a user s password...330 Creating a user account...330 Lost or forgotten root password...330 CD-ROM Drive Not Detected During Installation...331 CD-ROM Drive Does Not Mount After Installation...332 Sound Does Not Work After Installation...332 Unable to Unmount a Drive...333 System Hangs During Boot...334 Unable to Access Network Hosts...335 Making an Emergency Boot Disk...336 Shell Commands Don t Work...336 Sources of Additional Information...337
xvi Red Hat Enterprise Linux 4 For Dummies Part VII: Appendixes...339 Appendix A: Installing Red Hat Enterprise Linux................341 Exploring Your PC s Components...341 Processor...342 Bus type...342 Memory...343 Video card and monitor...343 Hard drive...344 Floppy disk drive...344 Keyboard and mouse...344 SCSI controller...345 CD-ROM drive...345 Sound card...345 Network card...345 Checking for Supported Hardware...346 Starting the Red Hat Enterprise Linux Installation...346 Partitioning the Hard Disk for Red Hat Enterprise Linux...349 Configuring Red Hat Enterprise Linux Installation...351 Configuring the boot loader...352 Configuring the network...353 Configuring the firewall...354 Configuring additional languages...356 Setting the time zone...356 Setting the root password...357 Selecting the package groups to install...357 Completing the Installation...359 Appendix B: What s on the CD-ROM?..........................361 Index...369