DataBook® for Linux
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  • About
    • Legal
    • GNU Free Documentation License
    • Glossary
    • Bibliography
    • Decimal Naming and Prefixes
    • Contact
  • What is an Operating System
    • Definition of an Operating System
      • Genesis of the Operating System
      • Operating System Functions
    • A Little History of Linux
      • The Linux Philosophy
        • Linux Philosophy Saves the Day – Automate Everything!
        • Everything is a File – A Critical Concept
        • The Linux Philosophy — Oregon State University
        • Quotes
        • The real reason we use Linux
  • News and Reviews
    • Fedora 21 – Major changes to installation options
    • VirtualBox – Free and Easy Virtualization
  • DataBook for Linux Administrators
    • Fedora and Red Hat Documentation
    • Installation
      • Creating and Using Live Images
        • Creating a live Fedora USB image from the command line
        • Write Protect Errors Creating Bootable USB Thumb Drives
        • Error creating Live CD ISO Image
        • Creating USB Drive Install Image for Fedora
        • Making a Bootable USB Thumb Drive For Installation
      • Using the New Anaconda Installer in Fedora 18 and Above
      • Errors During Fedora Linux DVD Installation
      • Hardware Compatibility
        • BIOS Upgrades with FreeDOS
        • Testing hardware compatibility with Linux using Live USB memory sticks
        • nVidia vs ATI/Radeon Video
        • Video Hardware
        • Getting Linux to Run on Intel DG33FB Motherboard
        • Intel DP35DP Motherboard And Fedora
        • Beware of Foxconn Motherboards
      • Software RAID
        • Configuring Software RAID1 Arrays in Linux
        • Failing and Removing a Device From a RAID 1 Array in Linux
      • Default Partitioning and Disk Layout During Installation
      • Advanced Partitioning and Disk Layout During Installation
      • Kickstart
        • Complete Kickstart
      • Sample Linux Installation Procedures
        • Installing Fedora Linux 15 Through 17
        • Installing Fedora Linux 18
        • Fedora 15 through 18 Post Installation
        • Installing Fedora Linux 19
      • Post-Installation Problems
        • SSH and YUM don’t work after Fedora 10 Installation
    • Upgrades
      • Upgrade Fedora with dnf system-upgrade – Fedora 22 and above
      • Upgrades with fedup – not so much!
      • Upgrades with preupgrade
      • Upgrades not recommended with Fedora 18 through 22
      • Fedora 11 Upgrade Problems With YUM
      • Boot Fails After Upgrade from Fedora 10 to Fedora 11
      • Applications Won’t Start After Fedora 10 Upgrade
    • Migrating to Linux
      • Creating a Default KDE Desktop for New Accounts
      • Migrating Microsoft Contacts to Thunderbird
      • Importing Local Folders From Microsoft Mail into Thunderbird
    • Starting Linux
      • The Linux Boot Process
        • BIOS POST
        • GRUB
          • Configuring GRUB
          • Using the GRUB Menu to Alter the Boot Sequence
        • Kernel Boot Parameters
        • Kernel Initialization
        • GRUB2
          • Configuring GRUB2
      • Startup Using SystemV Init Scripts
        • Understanding Run Levels
        • init
        • Understanding /etc/inittab
        • rc.sysinit
        • rc
      • The startup process using systemd
        • Starting and Managing Linux Services Using systemd
      • Setting the host name
    • Filesystems
      • Anatomy of a Disk Drive
      • Disk Drive Types
      • The Linux Kernel and HDD Types
      • Introduction to Linux Filesystems
      • Filesystem Hierarchy Standard
      • Understanding the /dev directory
      • The Linux Extended Filesystems
        • EXT2 Filesystem
        • The Linux EXT4 filesystem
      • Using hard and soft links in the Linux filesystem
      • Logical Volume Manager – LVM
        • LVM Structure
        • Creating a new Volume Group and Logical Volume
        • Resizing a Logical Volume in an LVM Filesystem
        • Changing the name of a Volume Group
      • Using the Loopback devices
      • File Permissions
      • Managing Cruft in tmp directories
    • Swap space on Linux Systems
      • Adding more swap space
    • The Command Line Interface (CLI)
      • Using Screen
      • Using Virtual Consoles
      • Tilix – Extreme Terminal Emulation
      • The GNU Core Utilities
      • Pipe Dreams
      • Fedora 16 crontab Problem
      • Setting vi Mode for Command Line Editing
    • System Tools
      • The /proc filesystem
      • Setting Colors in vim
      • Colors in Midnight Commander
      • The date Command
    • System Administration
      • Everything is a File
      • Linux Standards and Best Practices
      • About UDEV
      • Serial Console Usage
      • Performance Tuning
        • Removing kactivitymanagerd
        • KDE — How to disable Nepomuk, Strigi, Baloo and Akonadi
        • Removing ModemManager
      • When to reboot a Linux computer
    • Software Updates
      • How to Disable PackageKit
    • Networking
      • BIND and Named – Name Services
        • Introduction to the Domain Name System (DNS)
        • Set up a DNS server using BIND
        • DNS secondary server does not update
        • DNS Problems in Fedora 12 and 13
      • Network Manager
        • Disable NetworkManager
      • Network Configuration
        • CIDR – Network notation and configuration
        • Introduction to Network Routing
        • Making your Linux Box Into a Router
        • Configuring Network Interface Controllers (NIC)
      • Networking Problems
        • Intel e1000e link speed only 100Mb rather than 1000Mb
        • Resetting Stale NFS Handles in Linux
      • Network Interface Card (NIC) name assignments
    • Printing
      • Printing Problems After Upgrade from Fedora 10 to 11
      • Printer Won’t Print After Going Into Sleep Mode
      • Printing With a Xerox WorkCenter Pro 128
      • Printing with the Dell V505 All-In-One Printer
      • Lexmark Printers Not Supported in Linux
    • The X Window System
      • Installing System Fonts Using the Command Line
      • The Display Manager
      • xorg.conf Not Created in Fedora 14
    • Security
      • Generating passwords
      • Firewalls
        • New Firewall – firewalld
        • Reverting to IPTables from firewalld
        • Blocking Brute Force SSH Attacks
      • shred – Deleting Files Securely
      • Backups and Disaster Recovery
        • The Backup Plan
        • Using tar and ssh for backups
        • Using rsync for Backup
    • Scripting Languages
      • BASH Code to Determine Valid IP Addresses
      • The awk Language
    • Apache Web Server
      • Basic Apache Web Server Configuration
      • Configuring multiple web sites with Apache
      • Configuration changes in Apache 2.4
    • Email
      • Configuring the Alpine email client
      • Sorting Email – Using SpamAssassin, MimeDefang and Procmail
      • sendmail
        • SendMail Error Message: 553 5.1.8 … Domain of sender address … does not exist
        • Outbound Authentication for Sendmail
        • Forwarding Email from Hosts with no DNS Entries
        • Using port forwarding when ISP’s block port 25 for outbound email
      • Can’t connect on IMAP to receive email on mobile devices – Server busy error
    • Troubleshooting
      • The Five Steps of Problem Solving
        • Knowledge
        • Observation
        • Deduction
        • Action
        • Testing
      • Troubleshooting Example
      • Important First Steps in Solving Problems
      • Problem Determination Tools
        • Open source tools for monitoring your Linux system
        • Temperature monitoring tools to keep your Linux computer cool
        • top
        • Diagnosing CPU and memory related performance problems
        • Priorities, Nice Numbers and How to Use Them
      • Environmental Problems – EMI
        • EMI Sources
          • EMI – Radio and TV
          • EMI – Radar and Microwave
          • EMI – Static Electricity
          • EMI – Electrical Noise
          • EMI – Engines
          • EMI – Magnetic Fields
        • EMI Problems – Bothering your Neighbors
        • How to Minimize EMI Problems
      • Specific Problems
        • TigerVNC viewer blank
        • Cannot Login Using GUI
        • Horizontal Bar in Display
        • Xterm Windows Freeze Up in VNC Session
        • Fedora 10 – Network Only Works Outbound
    • Compiling the Kernel
      • Using Multiple Threads When Compiling the Kernel
    • Applications
      • ChurchInfo
        • ChurchInfo: Fatal Error: $_SESSION[‘sURLPath’] is empty
        • Installing ChurchInfo
        • ChurchInfo: Empty pages
      • WordPress
        • WordPress xmlrpc.php vulnerability
      • VirtualBox
        • VirtualBox VMs Very Slow
        • Installing VirtualBox Using the RPMFusion Repository
        • Sharing Virtual Machines on a Single VirtualBox Host
        • Making USB Work in VirtualBox Guests
      • Setting User Interface Fonts for Firefox and Thunderbird
    • Multimedia
      • Troubleshooting Audio Adapter Problems
  • DataBook for Linux Users
    • Introduction
      • Linux Distributions
    • Section: The Basics
      • Chapter — How Do I Get Started?
        • Turning the Computer On
        • Login to the Computer
        • Make KDE Your Default Desktop
        • Linux and Security
        • When You Are Finished Using the Computer
      • Chapter — Introduction to Graphical User Interfaces (GUI)
        • Using Multiple Desktops
        • Anatomy of a Window
      • Chapter — Using KDE 3.5
        • 1. Kool Desktop Environment
        • 2. The KDE Panel
          • 1. Anatomy of the KDE Panel
          • 2. Configuring the KDE Panel
        • 3. The KDE Menu
        • 5. Switching Users
        • 6. Configuring KDE
          • Changing the Look of KDE
            • 1. KDE Themes
            • 2. Changing the Background
            • 3. Choosing a Color Scheme
            • 4. Fonts
            • 5. Icons
            • 6. Launch Feedback
            • 7. Screen Saver
            • 8. Splash Screen
            • 9. Style
            • 10. Theme Manager
            • 11. Window Decorations
          • Changing How The Desktop Works
            • 1. Behavior
            • 2. Multiple Desktops
            • 3. Panels
            • 4. Task Bar
            • 5. Window Behavior
          • Peripherals
            • Mouse
          • What Happens to My Changes When I Upgrade?
          • Getting Back to the Defaults
      • Chapter — Using KDE 4
        • Introducing KDE 4
        • The KDE 4 Panel
          • Anatomy of the KDE 4 Panel
          • Configuring the KDE 4 Panel
        • The KDE 4 Menu
        • Switching Users
        • KDE4 Problem Solving
          • Reset KDE Wallet Password
    • Section: Managing Files
      • Computer Memory — RAM vs Disk Drives and Files
      • Searching for Files with KDE
      • Comparison of Common File Managers
      • Using the Dolphin File Manager
      • Using Midnight Commander
      • Using Konqueror
      • Associating Files with Application Programs
      • Using the Krusader file manager
      • Using the Standard KDE File Manager to Save Files
      • Extracting Zip Archives
    • Section: Internet Applications
      • Chapter — Email with Thunderbird
        • Setting Font Sizes for Message Text in Thunderbird
        • Multipurpose Internet Mail Extensions (MIME)
        • Opening Attachments Directly From Thunderbird
        • Saving Attachments and Photos
      • Chapter — Surfing the Internet With Firefox
        • Tabbed Browsing with Firefox
        • Viewing Embedded Documents and Videos with Firefox
        • Error: Firefox is already running
    • Chapter — Multimedia
      • Using K3B to Burn a CD or DVD
      • Choosing a Webcam for Linux
      • Basic Scanning with XSane
    • Chapter — Application Programs
      • GnuCash
      • LibréOffice
      • OpenOffice
        • Dealing with Word Document Formatting Problems
    • Chapter — Printing in Linux
    • Chapter — Problem Solving
      • Recovering from a Display Problem
  • DataBook for OS/2
    • Front Material
      • Notes About The Rebuild of the DataBook for OS/2 Warp
      • Forward
      • Warp Products Covered by the DataBook For OS/2
      • OS/2 Reference Books
    • Chapter 1 – What is an Operating System and why is it Important?
      • Computers and Technology In Today’s Business
        • Wasted Computing Power
        • Why Multitasking?
        • Multitasking in Windows 3.1
        • Multitasking in Windows 95
        • Multitasking in Windows NT
        • Multitasking in OS/2 Warp
        • Computer-Centric Strategies for Enhancing Productivity
        • SETI@Home – A Perfect Example of Multitasking
      • What is OS/2 Warp?
        • Introducing OS/2 Warp
        • Warp Features
        • Warp Server
        • OS/2 Awards
        • A Short History of OS/2
        • The Future of OS/2
      • Who Uses OS/2 Warp
        • When was the last time you used OS/2
        • Who uses Warp in North America
        • Who uses OS/2 Warp in Europe
        • Who uses OS/2 in Asia
        • Who uses OS/2 elsewhere
      • Introduction To Operating Systems
        • Defining an Operating System
        • Genesis of the Operating System
        • Operating System Features
        • OS/2 Warp from a Programmer’s Viewpoint
    • Chapter 02 – Inside OS/2 Warp
      • The OS/2 Kernel
      • OS/2 Multitasking
      • OS/2 Crash Protection
      • The Swap File
      • OS/2 Memory Management
      • Ring Protection mechanism
      • Dynamic Link Libraries – DLL
      • Symmetric MultiProcessing (SMP)
  • Downloads
  • Humor
    • Blinkenlights
    • The Gospel of Tux (v1.0)
    • The ABC’s of Unix
    • The Perfect Programmer

Firewalls

Up one level: Security
Previous: Generating passwords
Next: New Firewall – firewalld


This section of the DataBook for Linux Administrators contains information about the two firewalls used in Fedora.

  • IPTables
  • firewalld

Starting with Fedora 18, firewalld replaces the older IPTables firewall.

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Up one level: Security
Previous: Generating passwords
Next: New Firewall – firewalld


Random Quote

The value of a program is proportional to the weight of its output.

— Laws of Computer Programming

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Newest Pages

  • Blinkenlights
    11-10-2018
  • TigerVNC viewer blank
    07-03-2018
  • The GNU Core Utilities
    06-11-2018
  • Removing kactivitymanagerd
    06-01-2018
  • Configuring multiple web sites with Apache
    03-25-2018
  • Basic Apache Web Server Configuration
    03-25-2018
  • Sorting Email - Using SpamAssassin, MimeDefang and Procmail
    03-23-2018
  • Configuring the Alpine email client
    03-22-2018
  • Downloads
    02-10-2018
  • Tilix - Extreme Terminal Emulation
    08-25-2017
  • Understanding the /dev directory
    07-22-2017
  • Using hard and soft links in the Linux filesystem
    07-22-2017

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Admin Tools

  • 80 Linux Monitoring Tools for SysAdmins

Distributions

  • CentOS
  • DistroWatch
  • Fedora Project
  • Red Hat

Documentation

  • Fedora Documentation
  • LibreOffice Documentation
  • Red Hat Documentation
  • The job is not done until the documentation is complete

Enlightenment

  • Nine traits of the veteran Unix admin
  • Open Life: The Philosophy of Open Source
  • Open Sources : Voices from the Open Source Revolution
  • The Art of Unix Programming
  • The Tao of Open Source
  • The Tao of Programming
  • The Unix Power Classic

Filesystem

  • Filesystem Hierarchy Standard

History

  • Arnold Robbins home page
  • Unix pioneers reminisce

Linux

  • How to do fast, repeatable Linux installations
  • Linux monitoring tools to keep your hardware cool
  • My mom requests a Linux computer
  • Red Hat
  • RPMFusion Repositories
  • The Art of Unix Programming
  • The job is not done until the documentation is complete
  • The Tao of Programming
  • The Unix Power Classic
  • Why Linux is Better

Linux Boot

  • Linux Kernel Boot Process

My Articles

  • 8 Linux file managers to try
  • 9 reasons to use KDE
  • A comprehensive guide to Dolphin, a KDE file manager
  • A troubleshooting process for Linux problems
  • Complete Kickstart
  • Everything is a file
  • Get started with Midnight Commander, a Linux file manager
  • How I landed a job in open source
  • How the 9 major tenets of the Linux philosophy affect you
  • How to do fast, repeatable Linux installations
  • Human Interface Guidelines (HIG) for the Unix shell
  • Linux monitoring tools to keep your hardware cool
  • My mom requests a Linux computer
  • Solving City Problems the Open Source Way
  • Take control of your file systems with Konqueror
  • The impact of the Linux philosophy
  • The job is not done until the documentation is complete

Open Source

  • GnuCash Accounting Software
  • How the 9 major tenets of the Linux philosophy affect you
  • How to do fast, repeatable Linux installations
  • LibreOffice
  • OpenSource.com
  • Solving City Problems the Open Source Way
  • The impact of the Linux philosophy

OpenSource.com

  • How the 9 major tenets of the Linux philosophy affect you
  • How to do fast, repeatable Linux installations
  • Human Interface Guidelines (HIG) for the Unix shell
  • Linux monitoring tools to keep your hardware cool
  • My mom requests a Linux computer
  • Solving City Problems the Open Source Way
  • The impact of the Linux philosophy
  • The job is not done until the documentation is complete

Package Repositories

  • EPEL
  • RPMFusion Repositories

Software

  • FreeOpenSourceSoftware.org
  • GnuCash Accounting Software
  • LibreOffice

Unix

  • Arnold Robbins home page
  • Unix pioneers reminisce

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