book

Fedora® Linux® TOOLBOX: 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users

Name: Fedora® Linux® TOOLBOX: 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users
ISBN: 9780470082911

by François Caen, Christopher Negus

November 2007

Beginner

307 pages

7h 27m

English

Wiley

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Copyright
About the Authors
Credits
Acknowledgments
Introduction
Who Should Read This BookWhat This Book CoversHow This Book Is StructuredWhat You Need to Use This BookConventions
1. Starting with Fedora Linux
1.1. About Fedora, Red Hat, and Linux1.1.1. Comparing Fedora to Other Linuxes1.1.2. Finding Fedora Resources1.1.2.1. Fedora Community Connections1.1.2.2. Fedora Software1.2. Focusing on Linux Commands1.2.1. Finding Commands1.2.2. Command Reference Information in Fedora1.2.2.1. Using help Messages1.2.2.2. Using man Pages1.2.2.3. Using info Documents1.3. Summary
2. Installing Fedora and Adding Software
2.1. Installing Fedora2.1.1. Preparing to Install2.1.2. Choosing Installation Options2.1.2.1. Starting the Install Process2.1.2.2. Choosing Where Fedora Software Is from the Boot Screen2.1.2.3. Choosing How Install Proceeds from the Boot Screen2.1.2.4. Choosing More Boot Options2.1.3. Answering Installation Questions2.2. Working with Software Packages2.3. Using yum Software Repositories2.3.1. Enabling Repositories for yum2.3.2. Using the yum Command2.3.2.1. Finding Packages2.3.2.2. Installing Packages2.3.2.3. Updating Packages2.3.2.4. Removing Packages2.3.2.5. Cleaning Up Packages2.3.2.6. Useful Combinations of Options2.3.3. Using yum Utilities2.4. Managing Software with rpm2.4.1. Using the rpm Command2.4.1.1. Installing a Package2.4.1.2. Upgrading a Package2.4.1.3. Removing a Package2.4.1.4. Querying Information about RPM Packages2.4.1.5. Verifying Installed Packages2.4.1.6. Rebuilding Your RPM Database2.4.2. Building RPMs from SRPMs2.4.3. Extracting Files from RPMs2.5. Summary
3. Using the Shell
3.1. Terminal Windows and Shell Access3.1.1. Using Terminal Windows3.1.2. Using Virtual Terminals3.2. Using the Shell3.2.1. Using Bash History3.2.2. Using Command Line Completion3.2.3. Redirecting stdin and stdout3.2.4. Using alias3.2.5. Watching Commands3.2.6. Watching Files3.3. Acquiring Super User Power3.3.1. Using the su Command3.3.2. Delegating Power with sudo3.4. Using Environment Variables3.5. Creating Simple Shell Scripts3.5.1. Editing and Running a Script3.5.2. Adding Content to Your Script3.6. Summary
4. Working with Files
4.1. Understanding File Types4.1.1. Using Regular Files4.1.2. Using Directories4.1.3. Using Symbolic and Hard Links4.1.4. Using Device Files4.1.5. Using Named Pipes and Sockets4.2. Setting File/Directory Permissions4.2.1. Changing Permissions with chmod4.2.2. Setting the umask4.2.3. Changing Ownership4.3. Traversing the File System4.4. Copying Files4.5. Changing File Attributes4.6. Searching for Files4.6.1. Finding Files with locate4.6.2. Locating Files with find4.6.3. Using Other Commands to Find Files4.7. Finding Out More About Files4.7.1. Listing Files4.7.2. Verifying Files4.8. Summary
5. Manipulating Text
5.1. Matching Text with Regular Expressions5.2. Editing Text Files5.2.1. Using the JOE Editor5.2.2. Using the pico and nano Editors5.2.3. Graphical Text Editors5.3. Listing, Sorting, and Changing Text5.3.1. Listing Text Files5.3.2. Paging Through Text5.3.3. Paginating Text Files with pr5.3.4. Searching for Text with grep5.3.4.1. Checking Word Counts with wc5.3.4.2. Sorting Output with sort5.3.4.3. Finding Text in Binaries with Strings5.3.5. Replacing Text with sed5.3.6. Translating or Removing Characters with tr5.3.7. Checking Differences Between Two Files with diff5.3.8. Using awk and cut to Process Columns5.3.9. Converting Text Files to Different Formats5.4. Summary

6. Playing with Multimedia
6.1. Working with Audio6.1.1. Playing Music6.1.2. Adjusting Audio Levels6.1.3. Ripping CD Music6.1.4. Encoding Music6.1.5. Streaming Music6.1.6. Converting Audio Files6.2. Transforming Images6.2.1. Getting Information about Images6.2.2. Converting Images6.2.3. Converting Images in Batches6.3. Summary
7. Administering File Systems
7.1. Understanding File System Basics7.2. Creating and Managing File Systems7.2.1. Partitioning Hard Disks7.2.1.1. Changing Disk Partitions with fdisk7.2.1.2. Copying Partition Tables with s fdisk7.2.1.3. Changing Disk Partitions with parted7.2.2. Working with File System Labels7.2.3. Formatting a File System7.2.3.1. Creating a File System on a Hard Disk Partition7.2.3.2. Creating a Virtual File System7.2.4. Viewing and Changing File System Attributes7.2.5. Creating and Using Swap Partitions7.3. Mounting and Unmounting File Systems7.3.1. Mounting File Systems from the fstab File7.3.2. Mounting File Systems with the mount Command7.3.3. Unmounting File Systems with umount7.4. Checking File Systems7.5. Checking RAID Disks7.6. Finding Out About File System Use7.6.1. Logical Volume Manager7.6.2. Creating LVM Volumes7.6.3. Using LVM Volumes7.6.4. Growing the LVM Volume7.6.5. Shrinking an LVM Volume7.6.6. Removing LVM Logical Volumes and Groups7.7. Summary
8. Backups and Removable Media
8.1. Backing Up Data to Compressed Archives8.1.1. Creating Backup Archives with tar8.1.2. Using Compression Tools8.1.2.1. Compressing with gzip8.1.2.2. Compressing with bzip28.1.2.3. Compressing with lzop8.1.3. Listing, Joining, and Adding Files to tar Archives8.1.4. Deleting Files from tar Archives8.2. Backing Up Over Networks8.2.1. Backing Up tar Archives Over ssh8.2.2. Backing Up Files with rsync8.2.3. Backing Up with unison8.2.4. Backing Up to Removable Media8.2.5. Creating Backup Images with mkisofs8.2.6. Burning Backup Images with cdrecord8.2.7. Making and Burning DVDs with growisofs8.3. Summary
9. Checking and Managing Running Processes
9.1. Listing Active Processes9.1.1. Viewing Active Processes with ps9.1.2. Watching Active Processes with top9.2. Finding and Controlling Processes9.2.1. Using pgrep to Find Processes9.2.2. Using fuser to Find Processes9.2.3. Changing Running Processes9.2.3.1. Adjusting Processor Priority with nice9.2.3.2. Running Processes in the Background and Foreground9.2.3.3. Killing and Signaling Processes9.2.3.4. Running Processes Away from the Current Shell9.2.3.5. Scheduling Processes to Run9.3. Summary
10. Managing the System
10.1. Monitoring Resources10.1.1. Monitoring Memory Use10.1.2. Monitoring CPU Usage10.1.3. Monitoring Storage Devices10.2. Mastering Time10.2.1. Changing Time/Date with Graphical Tools10.2.2. Displaying and Setting Your System Clock10.2.3. Displaying and Setting Your Hardware Clock10.2.4. Using Network Time Protocol to Set Date/Time10.2.5. Trying Other Date/Time Commands10.3. Managing the Boot Process10.3.1. Using the GRUB Boot Loader10.3.2. Repairing the initial ramdisk (initrd)10.4. Controlling Startup and Run Levels10.5. Straight to the Kernel10.6. Poking at the Hardware10.7. Summary
11. Managing Network Connections
11.1. Configuring Networks from the GUI11.2. Managing Network Interface Cards11.3. Managing Network Connections11.3.1. Starting and Stopping Ethernet Connections11.3.2. Viewing Ethernet Connection Information11.4. Using Wireless Connections11.5. Using Dial-up Modems11.6. Checking Name Resolution11.7. Troubleshooting Network Problems11.7.1. Checking Connectivity to a Host11.7.2. Checking Address Resolution Protocol (ARP)11.7.3. Tracing Routes to Hosts11.7.4. Displaying netstat Connections and Statistics11.7.5. Other Useful Network Tools11.8. Summary
12. Accessing Network Resources
12.1. Running Commands to Browse the Web12.2. Transferring Files12.2.1. Downloading Files with wget12.2.2. Transferring Files with cURL12.2.3. Transfering Files with FTP Commands12.2.4. Using SSH Tools to Transfer Files12.2.4.1. Copying Remote Files with scp12.2.4.2. Copying Remote Files in sftp and lftp Sessions12.2.5. Using Windows File Transfer Tools12.3. Sharing Remote Directories12.3.1. Sharing Remote Directories with NFS12.3.1.1. Viewing and Exporting NFS Shares12.3.1.2. Mounting NFS Shares12.3.2. Sharing Remote Directories with Samba12.3.2.1. Viewing and Accessing Samba Shares12.3.2.2. Mounting Samba Shares12.3.2.3. Looking Up Samba Hosts12.3.2.4. Checking Samba Configuration12.3.3. Sharing Remote Directories with SSHFS12.4. Chatting with Friends in IRC12.5. Using Text-Based E-mail Clients12.5.1. Managing E-mail with mail12.5.2. Managing E-mail with mutt12.6. Summary
13. Doing Remote System Administration
13.1. Doing Remote Login and Tunneling with SSH13.1.1. Configuring SSH13.1.2. Logging in Remotely with ssh13.1.2.1. Accessing SSH on a Different Port13.1.2.2. Using SSH to Do Tunneling (X11 Port Forwarding)13.1.2.3. Tunneling for X11 Clients13.1.2.4. Tunneling for CUPS Printing Remote Administration13.1.2.5. Tunneling to an Internet Service13.1.2.6. Using SSH as a SOCKS Proxy13.1.2.7. Using ssh with Public Key Authentication13.1.2.8. Using Public Key Logins13.1.2.9. Saving Private Keys to Use from a USB Flash Drive13.2. Using screen: A Rich Remote Shell13.2.1.13.2.1.1. Reconnecting to a screen Session13.2.1.2. Naming screen Sessions13.2.1.3. Sharing screen Sessions13.3. Using a Remote Windows Desktop13.3.1. Connecting to a Windows Desktop with tsclient13.3.2. Connecting to a Windows Desktop with rdesktop13.4. Using Remote Linux Desktop and Applications13.5. Sharing Desktops Using VNC13.5.1. Setting Up the VNC Server13.5.2. Starting Up the VNC Client13.5.3. Using VNC on Untrusted Networks with SSH13.5.4. Sharing a VNC Desktop with Vino13.6. Summary
14. Locking Down Security
14.1. Working with Users and Groups14.1.1. Managing Users the GUI Way14.1.2. Adding User Accounts14.1.2.1. Changing useradd Defaults14.1.3. Modifying User Accounts14.1.4. Deleting User Accounts14.1.5. Managing Passwords14.1.6. Adding Groups14.2. Checking on Users14.3. Configuring the Built-In Firewall14.4. Working with System Logs14.5. Using Advanced Security Features14.6. Summary
A. Using vi or Vim Editors
A.1. Starting and Quitting the vi EditorA.2. Moving Around in viA.3. Changing and Deleting Text in viA.4. Using Miscellaneous CommandsA.5. Modifying Commands with NumbersA.6. Using Ex CommandsA.7. Working in Visual Mode
B. Shell Special Characters and Variables
B.1. Using Special Shell CharactersB.2. Using Shell Variables
C. Getting Information from /proc
C.1. Viewing /proc informationC.2. Changing /proc information

Content preview from Fedora® Linux® TOOLBOX: 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users

Chapter 14. Locking Down Security

IN THIS CHAPTER

Add user accounts and change user settings with useradd
Change user accounts with usermod
Delete users with userdel
Add, change, and manage passwords with passwd
Manage groups with groupadd, groupmod, and groupdel
See who's logged in with last, lastb, and who
Configure firewalls with iptables
Manage log files with logrotate and logwatch
Check out advanced security with SELinux, tripwire, and RPM

Securing your Linux system means first restricting access to the user accounts and services on that system. After that, security means checking that no one has gotten around the defenses you have set up.

Fedora, Red Hat Enterprise Linux, CentOS, and other systems based on those Linux distributions are designed to be secure by default. That means that there are no user accounts with blank passwords, that the firewall is restrictive by default, and that most network services (Web, FTP, and so on) are off by default (even if their software is installed).

Although many of the commands covered in this book can be used to check and improve the security of your Linux system, some basic Linux features are particularly geared toward security. For example, secure user accounts with good password protection, a solid firewall, and consistent logging (and log monitoring) are critical to having a secure Linux system. Commands related to those features, plus some advanced features, such as SELinux and tripwire, are covered in this chapter.

Working with Users and Groups ...

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Fedora® Linux® TOOLBOX: 1000+ Commands for Fedora, CentOS, and Red Hat® Power Users

by François Caen, Christopher Negus

Chapter 14. Locking Down Security

Working with Users and Groups ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.