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  5. Deployment Guide
  6. 48.5.5.3. Related Books
  1. Deployment Guide
  2. Introduction
    1. 1. Document Conventions
    2. 2. Send in Your Feedback
  3. I. File Systems
    1. 1. File System Structure
      1. 1.1. Why Share a Common Structure?
      2. 1.2. Overview of File System Hierarchy Standard (FHS)
        1. 1.2.1. FHS Organization
          1. 1.2.1.1. The /boot/ Directory
          2. 1.2.1.2. The /dev/ Directory
          3. 1.2.1.3. The /etc/ Directory
          4. 1.2.1.4. The /lib/ Directory
          5. 1.2.1.5. The /media/ Directory
          6. 1.2.1.6. The /mnt/ Directory
          7. 1.2.1.7. The /opt/ Directory
          8. 1.2.1.8. The /proc/ Directory
          9. 1.2.1.9. The /sbin/ Directory
          10. 1.2.1.10. The /srv/ Directory
          11. 1.2.1.11. The /sys/ Directory
          12. 1.2.1.12. The /usr/ Directory
          13. 1.2.1.13. The /usr/local/ Directory
          14. 1.2.1.14. The /var/ Directory
      3. 1.3. Special File Locations Under Red Hat Enterprise Linux
    2. 2. Using the mount Command
      1. 2.1. Listing Currently Mounted File Systems
      2. 2.2. Mounting a File System
        1. 2.2.1. Specifying the File System Type
        2. 2.2.2. Specifying the Mount Options
        3. 2.2.3. Sharing Mounts
        4. 2.2.4. Moving a Mount Point
      3. 2.3. Unmounting a File System
      4. 2.4. Additional Resources
        1. 2.4.1. Installed Documentation
        2. 2.4.2. Useful Websites
    3. 3. The ext3 File System
      1. 3.1. Features of ext3
      2. 3.2. Creating an ext3 File System
      3. 3.3. Converting to an ext3 File System
      4. 3.4. Reverting to an ext2 File System
    4. 4. The ext4 File System
      1. 4.1. Features of ext4
      2. 4.2. Managing an ext4 File System
      3. 4.3. Creating an ext4 File System
      4. 4.4. Mounting an ext4 File System
      5. 4.5. Resizing an ext4 File System
    5. 5. The proc File System
      1. 5.1. A Virtual File System
        1. 5.1.1. Viewing Virtual Files
        2. 5.1.2. Changing Virtual Files
        3. 5.1.3. Restricting Access to Process Directories
      2. 5.2. Top-level Files within the proc File System
        1. 5.2.1. /proc/apm
        2. 5.2.2. /proc/buddyinfo
        3. 5.2.3. /proc/cmdline
        4. 5.2.4. /proc/cpuinfo
        5. 5.2.5. /proc/crypto
        6. 5.2.6. /proc/devices
        7. 5.2.7. /proc/dma
        8. 5.2.8. /proc/execdomains
        9. 5.2.9. /proc/fb
        10. 5.2.10. /proc/filesystems
        11. 5.2.11. /proc/interrupts
        12. 5.2.12. /proc/iomem
        13. 5.2.13. /proc/ioports
        14. 5.2.14. /proc/kcore
        15. 5.2.15. /proc/kmsg
        16. 5.2.16. /proc/loadavg
        17. 5.2.17. /proc/locks
        18. 5.2.18. /proc/mdstat
        19. 5.2.19. /proc/meminfo
        20. 5.2.20. /proc/misc
        21. 5.2.21. /proc/modules
        22. 5.2.22. /proc/mounts
        23. 5.2.23. /proc/mtrr
        24. 5.2.24. /proc/partitions
        25. 5.2.25. /proc/pci
        26. 5.2.26. /proc/slabinfo
        27. 5.2.27. /proc/stat
        28. 5.2.28. /proc/swaps
        29. 5.2.29. /proc/sysrq-trigger
        30. 5.2.30. /proc/uptime
        31. 5.2.31. /proc/version
      3. 5.3. Directories within /proc/
        1. 5.3.1. Process Directories
          1. 5.3.1.1. /proc/self/
        2. 5.3.2. /proc/bus/
        3. 5.3.3. /proc/driver/
        4. 5.3.4. /proc/fs
        5. 5.3.5. /proc/ide/
          1. 5.3.5.1. Device Directories
        6. 5.3.6. /proc/irq/
        7. 5.3.7. /proc/net/
        8. 5.3.8. /proc/scsi/
        9. 5.3.9. /proc/sys/
          1. 5.3.9.1. /proc/sys/dev/
          2. 5.3.9.2. /proc/sys/fs/
          3. 5.3.9.3. /proc/sys/kernel/
          4. 5.3.9.4. /proc/sys/net/
          5. 5.3.9.5. /proc/sys/vm/
        10. 5.3.10. /proc/sysvipc/
        11. 5.3.11. /proc/tty/
        12. 5.3.12. /proc//
      4. 5.4. Using the sysctl Command
      5. 5.5. Additional Resources
        1. 5.5.1. Installed Documentation
        2. 5.5.2. Useful Websites
    6. 6. Redundant Array of Independent Disks (RAID)
      1. 6.1. What is RAID?
        1. 6.1.1. Who Should Use RAID?
        2. 6.1.2. Hardware RAID versus Software RAID
        3. 6.1.3. RAID Levels and Linear Support
      2. 6.2. Configuring Software RAID
        1. 6.2.1. Creating the RAID Partitions
        2. 6.2.2. Creating the RAID Devices and Mount Points
      3. 6.3. Managing Software RAID
        1. 6.3.1. Reviewing RAID Configuration
        2. 6.3.2. Creating a New RAID Device
        3. 6.3.3. Replacing a Faulty Device
        4. 6.3.4. Extending a RAID Device
        5. 6.3.5. Removing a RAID Device
        6. 6.3.6. Preserving the Configuration
      4. 6.4. Additional Resources
        1. 6.4.1. Installed Documentation
    7. 7. Swap Space
      1. 7.1. What is Swap Space?
      2. 7.2. Adding Swap Space
        1. 7.2.1. Extending Swap on an LVM2 Logical Volume
        2. 7.2.2. Creating an LVM2 Logical Volume for Swap
        3. 7.2.3. Creating a Swap File
      3. 7.3. Removing Swap Space
        1. 7.3.1. Reducing Swap on an LVM2 Logical Volume
        2. 7.3.2. Removing an LVM2 Logical Volume for Swap
        3. 7.3.3. Removing a Swap File
      4. 7.4. Moving Swap Space
    8. 8. Managing Disk Storage
      1. 8.1. Standard Partitions using parted
        1. 8.1.1. Viewing the Partition Table
        2. 8.1.2. Creating a Partition
          1. 8.1.2.1. Making the Partition
          2. 8.1.2.2. Formatting the Partition
          3. 8.1.2.3. Labeling the Partition
          4. 8.1.2.4. Creating the Mount Point
          5. 8.1.2.5. Add to /etc/fstab
        3. 8.1.3. Removing a Partition
        4. 8.1.4. Resizing a Partition
      2. 8.2. LVM Partition Management
    9. 9. Implementing Disk Quotas
      1. 9.1. Configuring Disk Quotas
        1. 9.1.1. Enabling Quotas
        2. 9.1.2. Remounting the File Systems
        3. 9.1.3. Creating the Quota Database Files
        4. 9.1.4. Assigning Quotas per User
        5. 9.1.5. Assigning Quotas per Group
        6. 9.1.6. Setting the Grace Period for Soft Limits
      2. 9.2. Managing Disk Quotas
        1. 9.2.1. Enabling and Disabling
        2. 9.2.2. Reporting on Disk Quotas
        3. 9.2.3. Keeping Quotas Accurate
      3. 9.3. Additional Resources
        1. 9.3.1. Installed Documentation
        2. 9.3.2. Related Books
    10. 10. Access Control Lists
      1. 10.1. Mounting File Systems
        1. 10.1.1. NFS
      2. 10.2. Setting Access ACLs
      3. 10.3. Setting Default ACLs
      4. 10.4. Retrieving ACLs
      5. 10.5. Archiving File Systems With ACLs
      6. 10.6. Compatibility with Older Systems
      7. 10.7. Additional Resources
        1. 10.7.1. Installed Documentation
        2. 10.7.2. Useful Websites
    11. 11. LVM (Logical Volume Manager)
      1. 11.1. What is LVM?
        1. 11.1.1. What is LVM2?
      2. 11.2. LVM Configuration
      3. 11.3. Automatic Partitioning
      4. 11.4. Manual LVM Partitioning
        1. 11.4.1. Creating the /boot Partition
        2. 11.4.2. Creating the LVM Physical Volumes
        3. 11.4.3. Creating the LVM Volume Groups
        4. 11.4.4. Creating the LVM Logical Volumes
      5. 11.5. Using the LVM utility system-config-lvm
        1. 11.5.1. Utilizing uninitialized entities
        2. 11.5.2. Adding Unallocated Volumes to a volume group
        3. 11.5.3. Migrating extents
        4. 11.5.4. Adding a new hard disk using LVM
        5. 11.5.5. Adding a new volume group
        6. 11.5.6. Extending a volume group
        7. 11.5.7. Editing a Logical Volume
      6. 11.6. Additional Resources
        1. 11.6.1. Installed Documentation
        2. 11.6.2. Useful Websites
  4. II. Package Management
    1. 12. Package Management with RPM
      1. 12.1. RPM Design Goals
      2. 12.2. Using RPM
        1. 12.2.1. Finding RPM Packages
        2. 12.2.2. Installing
          1. 12.2.2.1. Package Already Installed
          2. 12.2.2.2. Conflicting Files
          3. 12.2.2.3. Unresolved Dependency
        3. 12.2.3. Uninstalling
        4. 12.2.4. Upgrading
        5. 12.2.5. Freshening
        6. 12.2.6. Querying
        7. 12.2.7. Verifying
      3. 12.3. Checking a Package's Signature
        1. 12.3.1. Importing Keys
        2. 12.3.2. Verifying Signature of Packages
      4. 12.4. Practical and Common Examples of RPM Usage
      5. 12.5. Additional Resources
        1. 12.5.1. Installed Documentation
        2. 12.5.2. Useful Websites
        3. 12.5.3. Related Books
    2. 13. Package Management Tool
      1. 13.1. Listing and Analyzing Packages
      2. 13.2. Installing and Removing Packages
    3. 14. YUM (Yellowdog Updater Modified)
      1. 14.1. Setting Up a Yum Repository
      2. 14.2. yum Commands
      3. 14.3. yum Options
      4. 14.4. Configuring yum
        1. 14.4.1. [main] Options
        2. 14.4.2. [repository] Options
      5. 14.5. Upgrading the System Off-line with ISO and Yum
      6. 14.6. Useful yum Variables
    4. 15. Registering a System and Managing Subscriptions
      1. 15.1. Using Red Hat Subscription Manager Tools
        1. 15.1.1. Launching the Red Hat Subscription Manager GUI
        2. 15.1.2. Running the subscription-manager Command-Line Tool
      2. 15.2. Registering and Unregistering a System
        1. 15.2.1. Registering from the GUI
        2. 15.2.2. Registering from the Command Line
        3. 15.2.3. Unregistering
      3. 15.3. Attaching and Removing Subscriptions
        1. 15.3.1. Attaching and Removing Subscriptions through the GUI
          1. 15.3.1.1. Attaching a Subscription
          2. 15.3.1.2. Removing Subscriptions
        2. 15.3.2. Attaching and Removing Subscriptions through the Command Line
          1. 15.3.2.1. Attaching Subscriptions
          2. 15.3.2.2. Removing Subscriptions from the Command Line
      4. 15.4. Redeeming Vendor Subscriptions
        1. 15.4.1. Redeeming Subscriptions through the GUI
        2. 15.4.2. Redeeming Subscriptions through the Command Line
      5. 15.5. Attaching Subscriptions from a Subscription Asset Manager Activation Key
      6. 15.6. Setting Preferences for Systems
        1. 15.6.1. Setting Preferences in the UI
        2. 15.6.2. Setting Service Levels Through the Command Line
        3. 15.6.3. Setting a Preferred Operating System Release Version in the Command Line
        4. 15.6.4. Removing a Preference
      7. 15.7. Managing Subscription Expiration and Notifications
  5. III. Network-Related Configuration
    1. 16. Network Interfaces
      1. 16.1. Network Configuration Files
      2. 16.2. Interface Configuration Files
        1. 16.2.1. Ethernet Interfaces
        2. 16.2.2. IPsec Interfaces
        3. 16.2.3. Channel Bonding Interfaces
        4. 16.2.4. Alias and Clone Files
        5. 16.2.5. Dialup Interfaces
        6. 16.2.6. Other Interfaces
      3. 16.3. Interface Control Scripts
      4. 16.4. Static Routes and the Default Gateway
      5. 16.5. Configuring Static Routes in ifcfg files
        1. 16.5.1. Static Routes Using the IP Command Arguments Format
        2. 16.5.2. Network/Netmask Directives Format
      6. 16.6. Network Function Files
      7. 16.7. Additional Resources
        1. 16.7.1. Installed Documentation
    2. 17. Network Configuration
      1. 17.1. Overview
      2. 17.2. Establishing an Ethernet Connection
      3. 17.3. Establishing an ISDN Connection
      4. 17.4. Establishing a Modem Connection
      5. 17.5. Establishing an xDSL Connection
      6. 17.6. Establishing a Token Ring Connection
      7. 17.7. Establishing a Wireless Connection
      8. 17.8. Managing DNS Settings
      9. 17.9. Managing Hosts
      10. 17.10. Working with Profiles
      11. 17.11. Device Aliases
      12. 17.12. Saving and Restoring the Network Configuration
    3. 18. Controlling Access to Services
      1. 18.1. Runlevels
      2. 18.2. TCP Wrappers
        1. 18.2.1. xinetd
      3. 18.3. Services Configuration Tool
      4. 18.4. ntsysv
      5. 18.5. chkconfig
      6. 18.6. Additional Resources
        1. 18.6.1. Installed Documentation
        2. 18.6.2. Useful Websites
    4. 19. Berkeley Internet Name Domain (BIND)
      1. 19.1. Introduction to DNS
        1. 19.1.1. Nameserver Zones
        2. 19.1.2. Nameserver Types
        3. 19.1.3. BIND as a Nameserver
      2. 19.2. /etc/named.conf
        1. 19.2.1. Common Statement Types
          1. 19.2.1.1. acl Statement
          2. 19.2.1.2. include Statement
          3. 19.2.1.3. options Statement
          4. 19.2.1.4. zone Statement
          5. 19.2.1.5. Sample zone Statements
        2. 19.2.2. Other Statement Types
        3. 19.2.3. Comment Tags
      3. 19.3. Zone Files
        1. 19.3.1. Zone File Directives
        2. 19.3.2. Zone File Resource Records
        3. 19.3.3. Example Zone File
        4. 19.3.4. Reverse Name Resolution Zone Files
      4. 19.4. Using rndc
        1. 19.4.1. Configuring /etc/named.conf
          1. 19.4.1.1. Firewall Blocking Communication
        2. 19.4.2. Configuring /etc/rndc.conf
        3. 19.4.3. Command Line Options
      5. 19.5. Advanced Features of BIND
        1. 19.5.1. DNS Protocol Enhancements
        2. 19.5.2. Multiple Views
        3. 19.5.3. Security
        4. 19.5.4. IP version 6
      6. 19.6. Common Mistakes to Avoid
      7. 19.7. Additional Resources
        1. 19.7.1. Installed Documentation
        2. 19.7.2. Useful Websites
        3. 19.7.3. Related Books
    5. 20. OpenSSH
      1. 20.1. Features of SSH
        1. 20.1.1. Why Use SSH?
      2. 20.2. SSH Protocol Versions
      3. 20.3. Event Sequence of an SSH Connection
        1. 20.3.1. Transport Layer
        2. 20.3.2. Authentication
        3. 20.3.3. Channels
      4. 20.4. Configuring an OpenSSH Server
        1. 20.4.1. Requiring SSH for Remote Connections
      5. 20.5. OpenSSH Configuration Files
      6. 20.6. Configuring an OpenSSH Client
        1. 20.6.1. Using the ssh Command
        2. 20.6.2. Using the scp Command
        3. 20.6.3. Using the sftp Command
      7. 20.7. More Than a Secure Shell
        1. 20.7.1. X11 Forwarding
        2. 20.7.2. Port Forwarding
        3. 20.7.3. Generating Key Pairs
          1. 20.7.3.1. Generating an RSA Key Pair for Version 2
          2. 20.7.3.2. Generating a DSA Key Pair for Version 2
          3. 20.7.3.3. Generating an RSA Key Pair for Version 1.3 and 1.5
          4. 20.7.3.4. Configuring ssh-agent with a GUI
          5. 20.7.3.5. Configuring ssh-agent
      8. 20.8. Additional Resources
        1. 20.8.1. Installed Documentation
        2. 20.8.2. Useful Websites
    6. 21. Network File System (NFS)
      1. 21.1. How It Works
        1. 21.1.1. Required Services
      2. 21.2. NFS Client Configuration
        1. 21.2.1. Mounting NFS File Systems using /etc/fstab
      3. 21.3. autofs
        1. 21.3.1. What's new in autofs version 5?
        2. 21.3.2. autofs Configuration
        3. 21.3.3. autofs Common Tasks
          1. 21.3.3.1. Overriding or augmenting site configuration files
          2. 21.3.3.2. Using LDAP to Store Automounter Maps
          3. 21.3.3.3. Adapting Autofs v4 Maps To Autofs v5
      4. 21.4. Common NFS Mount Options
      5. 21.5. Starting and Stopping NFS
      6. 21.6. NFS Server Configuration
        1. 21.6.1. Exporting or Sharing NFS File Systems
        2. 21.6.2. Command Line Configuration
        3. 21.6.3. Running NFS Behind a Firewall
        4. 21.6.4. Hostname Formats
      7. 21.7. The /etc/exports Configuration File
        1. 21.7.1. The exportfs Command
          1. 21.7.1.1. Using exportfs with NFSv4
      8. 21.8. Securing NFS
        1. 21.8.1. Host Access
          1. 21.8.1.1. Using NFSv2 or NFSv3
          2. 21.8.1.2. Using NFSv4
        2. 21.8.2. File Permissions
      9. 21.9. NFS and portmap
        1. 21.9.1. Troubleshooting NFS and portmap
      10. 21.10. Using NFS over TCP
      11. 21.11. Additional Resources
        1. 21.11.1. Installed Documentation
        2. 21.11.2. Useful Websites
        3. 21.11.3. Related Books
    7. 22. Samba
      1. 22.1. Introduction to Samba
        1. 22.1.1. Samba Features
      2. 22.2. Samba Daemons and Related Services
        1. 22.2.1. Samba Daemons
      3. 22.3. Connecting to a Samba Share
        1. 22.3.1. Command Line
        2. 22.3.2. Mounting the Share
      4. 22.4. Configuring a Samba Server
        1. 22.4.1. Graphical Configuration
          1. 22.4.1.1. Configuring Server Settings
          2. 22.4.1.2. Managing Samba Users
          3. 22.4.1.3. Adding a Share
        2. 22.4.2. Command Line Configuration
        3. 22.4.3. Encrypted Passwords
      5. 22.5. Starting and Stopping Samba
      6. 22.6. Samba Server Types and the smb.conf File
        1. 22.6.1. Stand-alone Server
          1. 22.6.1.1. Anonymous Read-Only
          2. 22.6.1.2. Anonymous Read/Write
          3. 22.6.1.3. Anonymous Print Server
          4. 22.6.1.4. Secure Read/Write File and Print Server
        2. 22.6.2. Domain Member Server
          1. 22.6.2.1. Active Directory Domain Member Server
          2. 22.6.2.2. Windows NT4-based Domain Member Server
        3. 22.6.3. Domain Controller
          1. 22.6.3.1. Primary Domain Controller (PDC) using tdbsam
          2. 22.6.3.2. Primary Domain Controller (PDC) with Active Directory
      7. 22.7. Samba Security Modes
        1. 22.7.1. User-Level Security
          1. 22.7.1.1. Domain Security Mode (User-Level Security)
          2. 22.7.1.2. Active Directory Security Mode (User-Level Security)
          3. 22.7.1.3. Server Security Mode (User-Level Security)
        2. 22.7.2. Share-Level Security
      8. 22.8. Samba Account Information Databases
      9. 22.9. Samba Network Browsing
        1. 22.9.1. Domain Browsing
        2. 22.9.2. WINS (Windows Internetworking Name Server)
      10. 22.10. Samba with CUPS Printing Support
        1. 22.10.1. Simple smb.conf Settings
      11. 22.11. Samba Distribution Programs
      12. 22.12. Additional Resources
        1. 22.12.1. Installed Documentation
        2. 22.12.2. Related Books
        3. 22.12.3. Useful Websites
    8. 23. Dynamic Host Configuration Protocol (DHCP)
      1. 23.1. Why Use DHCP?
      2. 23.2. Configuring a DHCP Server
        1. 23.2.1. Configuration File
        2. 23.2.2. Lease Database
        3. 23.2.3. Starting and Stopping the Server
        4. 23.2.4. DHCP Relay Agent
      3. 23.3. Configuring a DHCP Client
      4. 23.4. Configuring a Multihomed DHCP Server
        1. 23.4.1. Host Configuration
      5. 23.5. Additional Resources
        1. 23.5.1. Installed Documentation
    9. 24. Migrating from MySQL 5.0 to MySQL 5.5
      1. 24.1. Upgrading from MySQL 5.0 to MySQL 5.5
    10. 25. Apache HTTP Server
      1. 25.1. Apache HTTP Server 2.2
        1. 25.1.1. Features of Apache HTTP Server 2.2
      2. 25.2. Migrating Apache HTTP Server Configuration Files
        1. 25.2.1. Migrating Apache HTTP Server 2.0 Configuration Files
        2. 25.2.2. Migrating Apache HTTP Server 1.3 Configuration Files to 2.0
          1. 25.2.2.1. Global Environment Configuration
            1. 25.2.2.1.1. Interface and Port Binding
            2. 25.2.2.1.2. Server-Pool Size Regulation
            3. 25.2.2.1.3. Dynamic Shared Object (DSO) Support
            4. 25.2.2.1.4. Other Global Environment Changes
          2. 25.2.2.2. Main Server Configuration
            1. 25.2.2.2.1. UserDir Mapping
            2. 25.2.2.2.2. Logging
            3. 25.2.2.2.3. Directory Indexing
            4. 25.2.2.2.4. Content Negotiation
            5. 25.2.2.2.5. Error Documents
          3. 25.2.2.3. Virtual Host Configuration
          4. 25.2.2.4. Modules and Apache HTTP Server 2.0
            1. 25.2.2.4.1. The suexec Module
            2. 25.2.2.4.2. The mod_ssl Module
            3. 25.2.2.4.3. The mod_proxy Module
            4. 25.2.2.4.4. The mod_include Module
            5. 25.2.2.4.5. The mod_auth_dbm and mod_auth_db Modules
            6. 25.2.2.4.6. The mod_perl Module
            7. 25.2.2.4.7. The mod_python Module
            8. 25.2.2.4.8. PHP
            9. 25.2.2.4.9. The mod_authz_ldap Module
      3. 25.3. Starting and Stopping httpd
      4. 25.4. Apache HTTP Server Configuration
        1. 25.4.1. Basic Settings
        2. 25.4.2. Default Settings
          1. 25.4.2.1. Site Configuration
          2. 25.4.2.2. SSL Support
          3. 25.4.2.3. Logging
          4. 25.4.2.4. Environment Variables
          5. 25.4.2.5. Directories
      5. 25.5. Configuration Directives in httpd.conf
        1. 25.5.1. General Configuration Tips
        2. 25.5.2. Configuration Directives for SSL
        3. 25.5.3. MPM Specific Server-Pool Directives
      6. 25.6. Adding Modules
      7. 25.7. Virtual Hosts
        1. 25.7.1. Setting Up Virtual Hosts
      8. 25.8. Apache HTTP Secure Server Configuration
        1. 25.8.1. An Overview of Security-Related Packages
        2. 25.8.2. An Overview of Certificates and Security
        3. 25.8.3. Using Pre-Existing Keys and Certificates
        4. 25.8.4. Types of Certificates
        5. 25.8.5. Generating a Key
        6. 25.8.6. How to configure the server to use the new key
      9. 25.9. Additional Resources
        1. 25.9.1. Useful Websites
    11. 26. FTP
      1. 26.1. The File Transfer Protocol
        1. 26.1.1. Multiple Ports, Multiple Modes
      2. 26.2. FTP Servers
        1. 26.2.1. vsftpd
        2. 26.2.2. Files Installed with vsftpd
        3. 26.2.3. Starting and Stopping vsftpd
          1. 26.2.3.1. Starting Multiple Copies of vsftpd
        4. 26.2.4. Encrypting vsftpd Connections Using TLS
        5. 26.2.5. vsftpd Configuration Options
          1. 26.2.5.1. Daemon Options
          2. 26.2.5.2. Log In Options and Access Controls
          3. 26.2.5.3. Anonymous User Options
          4. 26.2.5.4. Local User Options
          5. 26.2.5.5. Directory Options
          6. 26.2.5.6. File Transfer Options
          7. 26.2.5.7. Logging Options
          8. 26.2.5.8. Network Options
        6. 26.2.6. Additional Resources
          1. 26.2.6.1. Installed Documentation
          2. 26.2.6.2. Useful Websites
    12. 27. Email
      1. 27.1. Email Protocols
        1. 27.1.1. Mail Transport Protocols
          1. 27.1.1.1. SMTP
        2. 27.1.2. Mail Access Protocols
          1. 27.1.2.1. POP
          2. 27.1.2.2. IMAP
          3. 27.1.2.3. Dovecot
      2. 27.2. Email Program Classifications
        1. 27.2.1. Mail Transport Agent
        2. 27.2.2. Mail Delivery Agent
        3. 27.2.3. Mail User Agent
      3. 27.3. Mail Transport Agents
        1. 27.3.1. Sendmail
          1. 27.3.1.1. Purpose and Limitations
          2. 27.3.1.2. The Default Sendmail Installation
          3. 27.3.1.3. Common Sendmail Configuration Changes
          4. 27.3.1.4. Masquerading
          5. 27.3.1.5. Stopping Spam
          6. 27.3.1.6. Using Sendmail with LDAP
        2. 27.3.2. Postfix
          1. 27.3.2.1. The Default Postfix Installation
          2. 27.3.2.2. Basic Postfix Configuration
        3. 27.3.3. Fetchmail
          1. 27.3.3.1. Fetchmail Configuration Options
          2. 27.3.3.2. Global Options
          3. 27.3.3.3. Server Options
          4. 27.3.3.4. User Options
          5. 27.3.3.5. Fetchmail Command Options
          6. 27.3.3.6. Informational or Debugging Options
          7. 27.3.3.7. Special Options
      4. 27.4. Mail Transport Agent (MTA) Configuration
      5. 27.5. Mail Delivery Agents
        1. 27.5.1. Procmail Configuration
        2. 27.5.2. Procmail Recipes
          1. 27.5.2.1. Delivering vs. Non-Delivering Recipes
          2. 27.5.2.2. Flags
          3. 27.5.2.3. Specifying a Local Lockfile
          4. 27.5.2.4. Special Conditions and Actions
          5. 27.5.2.5. Recipe Examples
          6. 27.5.2.6. Spam Filters
      6. 27.6. Mail User Agents
        1. 27.6.1. Securing Communication
          1. 27.6.1.1. Secure Email Clients
          2. 27.6.1.2. Securing Email Client Communications
      7. 27.7. Additional Resources
        1. 27.7.1. Installed Documentation
        2. 27.7.2. Useful Websites
        3. 27.7.3. Related Books
    13. 28. Lightweight Directory Access Protocol (LDAP)
      1. 28.1. Why Use LDAP?
        1. 28.1.1. OpenLDAP Features
      2. 28.2. LDAP Terminology
      3. 28.3. OpenLDAP Daemons and Utilities
        1. 28.3.1. NSS, PAM, and LDAP
        2. 28.3.2. PHP4, LDAP, and the Apache HTTP Server
        3. 28.3.3. LDAP Client Applications
      4. 28.4. OpenLDAP Configuration Files
      5. 28.5. The /etc/openldap/schema/ Directory
      6. 28.6. OpenLDAP Setup Overview
        1. 28.6.1. Editing /etc/openldap/slapd.conf
      7. 28.7. Configuring a System to Authenticate Using OpenLDAP
        1. 28.7.1. PAM and LDAP
        2. 28.7.2. Migrating Old Authentication Information to LDAP Format
      8. 28.8. Migrating Directories from Earlier Releases
      9. 28.9. Additional Resources
        1. 28.9.1. Installed Documentation
        2. 28.9.2. Useful Websites
        3. 28.9.3. Related Books
    14. 29. Authentication Configuration
      1. 29.1. User Information
      2. 29.2. Authentication
      3. 29.3. Options
      4. 29.4. Command Line Version
    15. 30. Using and Caching Credentials with SSSD
      1. 30.1. About the sssd.conf File
      2. 30.2. Starting and Stopping SSSD
      3. 30.3. Configuring SSSD to Work with System Services
        1. 30.3.1. Configuring NSS Services
          1. 30.3.1.1. About NSS Service Maps and SSSD
          2. 30.3.1.2. Configuring NSS Services to Use SSSD
          3. 30.3.1.3. Configuring SSSD to Work with NSS
        2. 30.3.2. Configuring the PAM Service
      4. 30.4. Creating Domains
        1. 30.4.1. General Rules and Options for Configuring a Domain
        2. 30.4.2. Configuring an LDAP Domain
          1. 30.4.2.1. Parameters for Configuring an LDAP Domain
          2. 30.4.2.2. LDAP Domain Example
          3. 30.4.2.3. Active Directory Domain Example
          4. 30.4.2.4. Using IP Addresses in Certificate Subject Names
        3. 30.4.3. Configuring Kerberos Authentication with a Domain
        4. 30.4.4. Configuring a Proxy Domain
      5. 30.5. Configuring Access Control for SSSD Domains
        1. 30.5.1. Using the Simple Access Provider
        2. 30.5.2. Using the LDAP Access Filter
      6. 30.6. Configuring Domain Failover
        1. 30.6.1. Configuring Failover
        2. 30.6.2. Using SRV Records with Failover
      7. 30.7. Deleting Domain Cache Files
      8. 30.8. Using NSCD with SSSD
      9. 30.9. Troubleshooting SSSD
        1. 30.9.1. Checking SSSD Log Files
        2. 30.9.2. Problems with SSSD Configuration
  6. IV. System Configuration
    1. 31. Console Access
      1. 31.1. Disabling Shutdown Via Ctrl+Alt+Del
      2. 31.2. Disabling Console Program Access
      3. 31.3. Defining the Console
      4. 31.4. Making Files Accessible From the Console
      5. 31.5. Enabling Console Access for Other Applications
      6. 31.6. The floppy Group
    2. 32. The sysconfig Directory
      1. 32.1. Files in the /etc/sysconfig/ Directory
        1. 32.1.1. /etc/sysconfig/amd
        2. 32.1.2. /etc/sysconfig/apmd
        3. 32.1.3. /etc/sysconfig/arpwatch
        4. 32.1.4. /etc/sysconfig/authconfig
        5. 32.1.5. /etc/sysconfig/autofs
        6. 32.1.6. /etc/sysconfig/clock
        7. 32.1.7. /etc/sysconfig/desktop
        8. 32.1.8. /etc/sysconfig/dhcpd
        9. 32.1.9. /etc/sysconfig/exim
        10. 32.1.10. /etc/sysconfig/firstboot
        11. 32.1.11. /etc/sysconfig/gpm
        12. 32.1.12. /etc/sysconfig/hwconf
        13. 32.1.13. /etc/sysconfig/i18n
        14. 32.1.14. /etc/sysconfig/init
        15. 32.1.15. /etc/sysconfig/ip6tables-config
        16. 32.1.16. /etc/sysconfig/iptables-config
        17. 32.1.17. /etc/sysconfig/irda
        18. 32.1.18. /etc/sysconfig/kernel
          1. 32.1.18.1. Keeping an old kernel version as the default
          2. 32.1.18.2. Setting a kernel debugger as the default kernel
        19. 32.1.19. /etc/sysconfig/keyboard
        20. 32.1.20. /etc/sysconfig/kudzu
        21. 32.1.21. /etc/sysconfig/named
        22. 32.1.22. /etc/sysconfig/network
        23. 32.1.23. /etc/sysconfig/nfs
        24. 32.1.24. /etc/sysconfig/ntpd
        25. 32.1.25. /etc/sysconfig/radvd
        26. 32.1.26. /etc/sysconfig/samba
        27. 32.1.27. /etc/sysconfig/selinux
        28. 32.1.28. /etc/sysconfig/sendmail
        29. 32.1.29. /etc/sysconfig/spamassassin
        30. 32.1.30. /etc/sysconfig/squid
        31. 32.1.31. /etc/sysconfig/system-config-securitylevel
        32. 32.1.32. /etc/sysconfig/system-config-selinux
        33. 32.1.33. /etc/sysconfig/system-config-users
        34. 32.1.34. /etc/sysconfig/system-logviewer
        35. 32.1.35. /etc/sysconfig/tux
        36. 32.1.36. /etc/sysconfig/vncservers
        37. 32.1.37. /etc/sysconfig/xinetd
      2. 32.2. Directories in the /etc/sysconfig/ Directory
      3. 32.3. Additional Resources
        1. 32.3.1. Installed Documentation
    3. 33. Date and Time Configuration
      1. 33.1. Time and Date Properties
      2. 33.2. Network Time Protocol (NTP) Properties
      3. 33.3. Time Zone Configuration
    4. 34. Keyboard Configuration
    5. 35. The X Window System
      1. 35.1. The X11R7.1 Release
      2. 35.2. Desktop Environments and Window Managers
        1. 35.2.1. Desktop Environments
        2. 35.2.2. Window Managers
      3. 35.3. X Server Configuration Files
        1. 35.3.1. xorg.conf
          1. 35.3.1.1. The Structure
          2. 35.3.1.2. ServerFlags
          3. 35.3.1.3. ServerLayout
          4. 35.3.1.4. Files
          5. 35.3.1.5. Module
          6. 35.3.1.6. InputDevice
          7. 35.3.1.7. Monitor
          8. 35.3.1.8. Device
          9. 35.3.1.9. Screen
          10. 35.3.1.10. DRI
      4. 35.4. Fonts
        1. 35.4.1. Fontconfig
          1. 35.4.1.1. Adding Fonts to Fontconfig
        2. 35.4.2. Core X Font System
          1. 35.4.2.1. xfs Configuration
          2. 35.4.2.2. Adding Fonts to xfs
      5. 35.5. Runlevels and X
        1. 35.5.1. Runlevel 3
        2. 35.5.2. Runlevel 5
      6. 35.6. Additional Resources
        1. 35.6.1. Installed Documentation
        2. 35.6.2. Useful Websites
    6. 36. X Window System Configuration
      1. 36.1. Display Settings
      2. 36.2. Display Hardware Settings
      3. 36.3. Dual Head Display Settings
    7. 37. Users and Groups
      1. 37.1. User and Group Configuration
        1. 37.1.1. Adding a New User
        2. 37.1.2. Modifying User Properties
        3. 37.1.3. Adding a New Group
        4. 37.1.4. Modifying Group Properties
      2. 37.2. User and Group Management Tools
        1. 37.2.1. Command Line Configuration
        2. 37.2.2. Adding a User
        3. 37.2.3. Adding a Group
        4. 37.2.4. Password Aging
        5. 37.2.5. Explaining the Process
      3. 37.3. Standard Users
      4. 37.4. Standard Groups
      5. 37.5. User Private Groups
        1. 37.5.1. Group Directories
      6. 37.6. Shadow Passwords
      7. 37.7. Additional Resources
        1. 37.7.1. Installed Documentation
    8. 38. Printer Configuration
      1. 38.1. Adding a Local Printer
      2. 38.2. Adding an IPP Printer
      3. 38.3. Adding a Samba (SMB) Printer
      4. 38.4. Adding a JetDirect Printer
      5. 38.5. Selecting the Printer Model and Finishing
        1. 38.5.1. Confirming Printer Configuration
      6. 38.6. Printing a Test Page
      7. 38.7. Modifying Existing Printers
        1. 38.7.1. The Settings Tab
        2. 38.7.2. The Policies Tab
        3. 38.7.3. The Access Control Tab
        4. 38.7.4. The Printer and Job OptionsTab
      8. 38.8. Managing Print Jobs
      9. 38.9. Additional Resources
        1. 38.9.1. Installed Documentation
        2. 38.9.2. Useful Websites
    9. 39. Automated Tasks
      1. 39.1. Cron
        1. 39.1.1. Configuring Cron Jobs
        2. 39.1.2. Controlling Access to Cron
        3. 39.1.3. Starting and Stopping the Service
      2. 39.2. At and Batch
        1. 39.2.1. Configuring At Jobs
        2. 39.2.2. Configuring Batch Jobs
        3. 39.2.3. Viewing Pending Jobs
        4. 39.2.4. Additional Command Line Options
        5. 39.2.5. Controlling Access to At and Batch
        6. 39.2.6. Starting and Stopping the Service
      3. 39.3. Additional Resources
        1. 39.3.1. Installed Documentation
    10. 40. Log Files
      1. 40.1. Locating Log Files
      2. 40.2. Viewing Log Files
      3. 40.3. Adding a Log File
      4. 40.4. Monitoring Log Files
  7. V. System Monitoring
    1. 41. SystemTap
      1. 41.1. Introduction
      2. 41.2. Implementation
      3. 41.3. Using SystemTap
        1. 41.3.1. Tracing
          1. 41.3.1.1. Where to Probe
          2. 41.3.1.2. What to Print
    2. 42. Gathering System Information
      1. 42.1. System Processes
      2. 42.2. Memory Usage
      3. 42.3. File Systems
      4. 42.4. Hardware
      5. 42.5. Additional Resources
        1. 42.5.1. Installed Documentation
    3. 43. OProfile
      1. 43.1. Overview of Tools
      2. 43.2. Configuring OProfile
        1. 43.2.1. Specifying the Kernel
        2. 43.2.2. Setting Events to Monitor
          1. 43.2.2.1. Sampling Rate
          2. 43.2.2.2. Unit Masks
        3. 43.2.3. Separating Kernel and User-space Profiles
      3. 43.3. Starting and Stopping OProfile
      4. 43.4. Saving Data
      5. 43.5. Analyzing the Data
        1. 43.5.1. Using opreport
        2. 43.5.2. Using opreport on a Single Executable
        3. 43.5.3. Getting more detailed output on the modules
        4. 43.5.4. Using opannotate
      6. 43.6. Understanding /dev/oprofile/
      7. 43.7. Example Usage
      8. 43.8. Graphical Interface
      9. 43.9. Additional Resources
        1. 43.9.1. Installed Docs
        2. 43.9.2. Useful Websites
  8. VI. Kernel and Driver Configuration
    1. 44. Manually Upgrading the Kernel
      1. 44.1. Overview of Kernel Packages
      2. 44.2. Preparing to Upgrade
      3. 44.3. Downloading the Upgraded Kernel
      4. 44.4. Performing the Upgrade
      5. 44.5. Verifying the Initial RAM Disk Image
      6. 44.6. Verifying the Boot Loader
        1. 44.6.1. x86 Systems
          1. 44.6.1.1. GRUB
        2. 44.6.2. Itanium Systems
        3. 44.6.3. IBM S/390 and IBM System z Systems
        4. 44.6.4. IBM eServer iSeries Systems
        5. 44.6.5. IBM eServer pSeries Systems
    2. 45. General Parameters and Modules
      1. 45.1. Kernel Module Utilities
      2. 45.2. Persistent Module Loading
      3. 45.3. Specifying Module Parameters
      4. 45.4. Storage parameters
      5. 45.5. Ethernet Parameters
        1. 45.5.1. The Channel Bonding Module
          1. 45.5.1.1. bonding Module Directives
      6. 45.6. Additional Resources
        1. 45.6.1. Installed Documentation
        2. 45.6.2. Useful Websites
    3. 46. The kdump Crash Recovery Service
      1. 46.1. Installing the kdump Service
      2. 46.2. Configuring the kdump Service
        1. 46.2.1. Configuring kdump at First Boot
          1. 46.2.1.1. Enabling the Service
          2. 46.2.1.2. Configuring the Memory Usage
        2. 46.2.2. Using the Kernel Dump Configuration Utility
          1. 46.2.2.1. Enabling the Service
          2. 46.2.2.2. Configuring the Memory Usage
          3. 46.2.2.3. Configuring the Target Type
          4. 46.2.2.4. Configuring the Core Collector
          5. 46.2.2.5. Changing the Default Action
        3. 46.2.3. Configuring kdump on the Command Line
          1. 46.2.3.1. Configuring the Memory Usage
          2. 46.2.3.2. Configuring the Target Type
          3. 46.2.3.3. Configuring the Core Collector
          4. 46.2.3.4. Changing the Default Action
          5. 46.2.3.5. Enabling the Service
        4. 46.2.4. Testing the Configuration
      3. 46.3. Analyzing the Core Dump
        1. 46.3.1. Displaying the Message Buffer
        2. 46.3.2. Displaying a Backtrace
        3. 46.3.3. Displaying a Process Status
        4. 46.3.4. Displaying Virtual Memory Information
        5. 46.3.5. Displaying Open Files
      4. 46.4. Additional Resources
        1. 46.4.1. Installed Documentation
        2. 46.4.2. Useful Websites
  9. VII. Security And Authentication
    1. 47. Security Overview
      1. 47.1. Introduction to Security
        1. 47.1.1. What is Computer Security?
          1. 47.1.1.1. How did Computer Security Come about?
          2. 47.1.1.2. Security Today
          3. 47.1.1.3. Standardizing Security
        2. 47.1.2. Security Controls
          1. 47.1.2.1. Physical Controls
          2. 47.1.2.2. Technical Controls
          3. 47.1.2.3. Administrative Controls
        3. 47.1.3. Conclusion
      2. 47.2. Vulnerability Assessment
        1. 47.2.1. Thinking Like the Enemy
        2. 47.2.2. Defining Assessment and Testing
          1. 47.2.2.1. Establishing a Methodology
        3. 47.2.3. Evaluating the Tools
          1. 47.2.3.1. Scanning Hosts with Nmap
            1. 47.2.3.1.1. Using Nmap
          2. 47.2.3.2. Nessus
          3. 47.2.3.3. Nikto
          4. 47.2.3.4. VLAD the Scanner
          5. 47.2.3.5. Anticipating Your Future Needs
      3. 47.3. Attackers and Vulnerabilities
        1. 47.3.1. A Quick History of Hackers
          1. 47.3.1.1. Shades of Gray
        2. 47.3.2. Threats to Network Security
          1. 47.3.2.1. Insecure Architectures
            1. 47.3.2.1.1. Broadcast Networks
            2. 47.3.2.1.2. Centralized Servers
        3. 47.3.3. Threats to Server Security
          1. 47.3.3.1. Unused Services and Open Ports
          2. 47.3.3.2. Unpatched Services
          3. 47.3.3.3. Inattentive Administration
          4. 47.3.3.4. Inherently Insecure Services
        4. 47.3.4. Threats to Workstation and Home PC Security
          1. 47.3.4.1. Bad Passwords
          2. 47.3.4.2. Vulnerable Client Applications
      4. 47.4. Common Exploits and Attacks
      5. 47.5. Security Updates
        1. 47.5.1. Updating Packages
          1. 47.5.1.1. Using Automatic Updates with RHN Classic
          2. 47.5.1.2. Using the Red Hat Errata Website
          3. 47.5.1.3. Verifying Signed Packages
          4. 47.5.1.4. Installing Signed Packages
          5. 47.5.1.5. Applying the Changes
    2. 48. Securing Your Network
      1. 48.1. Workstation Security
        1. 48.1.1. Evaluating Workstation Security
        2. 48.1.2. BIOS and Boot Loader Security
          1. 48.1.2.1. BIOS Passwords
            1. 48.1.2.1.1. Securing Non-x86 Platforms
          2. 48.1.2.2. Boot Loader Passwords
            1. 48.1.2.2.1. Password Protecting GRUB
        3. 48.1.3. Password Security
          1. 48.1.3.1. Creating Strong Passwords
            1. 48.1.3.1.1. Secure Password Creation Methodology
          2. 48.1.3.2. Creating User Passwords Within an Organization
            1. 48.1.3.2.1. Forcing Strong Passwords
            2. 48.1.3.2.2. Password Aging
        4. 48.1.4. Administrative Controls
          1. 48.1.4.1. Allowing Root Access
          2. 48.1.4.2. Disallowing Root Access
          3. 48.1.4.3. Limiting Root Access
            1. 48.1.4.3.1. The su Command
            2. 48.1.4.3.2. The sudo Command
        5. 48.1.5. Available Network Services
          1. 48.1.5.1. Risks To Services
          2. 48.1.5.2. Identifying and Configuring Services
          3. 48.1.5.3. Insecure Services
        6. 48.1.6. Personal Firewalls
        7. 48.1.7. Security Enhanced Communication Tools
      2. 48.2. Server Security
        1. 48.2.1. Securing Services With TCP Wrappers and xinetd
          1. 48.2.1.1. Enhancing Security With TCP Wrappers
            1. 48.2.1.1.1. TCP Wrappers and Connection Banners
            2. 48.2.1.1.2. TCP Wrappers and Attack Warnings
            3. 48.2.1.1.3. TCP Wrappers and Enhanced Logging
          2. 48.2.1.2. Enhancing Security With xinetd
            1. 48.2.1.2.1. Setting a Trap
            2. 48.2.1.2.2. Controlling Server Resources
        2. 48.2.2. Securing Portmap
          1. 48.2.2.1. Protect portmap With TCP Wrappers
          2. 48.2.2.2. Protect portmap With iptables
        3. 48.2.3. Securing NIS
          1. 48.2.3.1. Carefully Plan the Network
          2. 48.2.3.2. Use a Password-like NIS Domain Name and Hostname
          3. 48.2.3.3. Edit the /var/yp/securenets File
          4. 48.2.3.4. Assign Static Ports and Use iptables Rules
          5. 48.2.3.5. Use Kerberos Authentication
        4. 48.2.4. Securing NFS
          1. 48.2.4.1. Carefully Plan the Network
          2. 48.2.4.2. Beware of Syntax Errors
          3. 48.2.4.3. Do Not Use the no_root_squash Option
        5. 48.2.5. Securing the Apache HTTP Server
          1. 48.2.5.1. FollowSymLinks
          2. 48.2.5.2. The Indexes Directive
          3. 48.2.5.3. The UserDir Directive
          4. 48.2.5.4. Do Not Remove the IncludesNoExec Directive
          5. 48.2.5.5. Restrict Permissions for Executable Directories
        6. 48.2.6. Securing FTP
          1. 48.2.6.1. FTP Greeting Banner
          2. 48.2.6.2. Anonymous Access
            1. 48.2.6.2.1. Anonymous Upload
          3. 48.2.6.3. User Accounts
            1. 48.2.6.3.1. Restricting User Accounts
          4. 48.2.6.4. Use TCP Wrappers To Control Access
        7. 48.2.7. Securing Sendmail
          1. 48.2.7.1. Limiting a Denial of Service Attack
          2. 48.2.7.2. NFS and Sendmail
          3. 48.2.7.3. Mail-only Users
        8. 48.2.8. Verifying Which Ports Are Listening
      3. 48.3. Single Sign-on (SSO)
        1. 48.3.1. Introduction
          1. 48.3.1.1. Supported Applications
          2. 48.3.1.2. Supported Authentication Mechanisms
          3. 48.3.1.3. Supported Smart Cards
          4. 48.3.1.4. Advantages of Red Hat Enterprise Linux Single Sign-on
        2. 48.3.2. Getting Started with your new Smart Card
          1. 48.3.2.1. Troubleshooting
        3. 48.3.3. How Smart Card Enrollment Works
        4. 48.3.4. How Smart Card Login Works
        5. 48.3.5. Configuring Firefox to use Kerberos for SSO
          1. 48.3.5.1. Troubleshooting
      4. 48.4. Pluggable Authentication Modules (PAM)
        1. 48.4.1. Advantages of PAM
        2. 48.4.2. PAM Configuration Files
          1. 48.4.2.1. PAM Service Files
        3. 48.4.3. PAM Configuration File Format
          1. 48.4.3.1. Module Interface
            1. 48.4.3.1.1. Stacking Module Interfaces
          2. 48.4.3.2. Control Flag
          3. 48.4.3.3. Module Name
          4. 48.4.3.4. Module Arguments
        4. 48.4.4. Sample PAM Configuration Files
        5. 48.4.5. Creating PAM Modules
        6. 48.4.6. PAM and Administrative Credential Caching
          1. 48.4.6.1. Removing the Timestamp File
          2. 48.4.6.2. Common pam_timestamp Directives
        7. 48.4.7. PAM and Device Ownership
          1. 48.4.7.1. Device Ownership
          2. 48.4.7.2. Application Access
        8. 48.4.8. Additional Resources
          1. 48.4.8.1. Installed Documentation
          2. 48.4.8.2. Useful Websites
      5. 48.5. TCP Wrappers and xinetd
        1. 48.5.1. TCP Wrappers
          1. 48.5.1.1. Advantages of TCP Wrappers
        2. 48.5.2. TCP Wrappers Configuration Files
          1. 48.5.2.1. Formatting Access Rules
            1. 48.5.2.1.1. Wildcards
            2. 48.5.2.1.2. Patterns
            3. 48.5.2.1.3. Portmap and TCP Wrappers
            4. 48.5.2.1.4. Operators
          2. 48.5.2.2. Option Fields
            1. 48.5.2.2.1. Logging
            2. 48.5.2.2.2. Access Control
            3. 48.5.2.2.3. Shell Commands
            4. 48.5.2.2.4. Expansions
        3. 48.5.3. xinetd
        4. 48.5.4. xinetd Configuration Files
          1. 48.5.4.1. The /etc/xinetd.conf File
          2. 48.5.4.2. The /etc/xinetd.d/ Directory
          3. 48.5.4.3. Altering xinetd Configuration Files
            1. 48.5.4.3.1. Logging Options
            2. 48.5.4.3.2. Access Control Options
            3. 48.5.4.3.3. Binding and Redirection Options
            4. 48.5.4.3.4. Resource Management Options
        5. 48.5.5. Additional Resources
          1. 48.5.5.1. Installed Documentation
          2. 48.5.5.2. Useful Websites
          3. 48.5.5.3. Related Books
      6. 48.6. Kerberos
        1. 48.6.1. What is Kerberos?
          1. 48.6.1.1. Advantages of Kerberos
          2. 48.6.1.2. Disadvantages of Kerberos
        2. 48.6.2. Kerberos Terminology
        3. 48.6.3. How Kerberos Works
        4. 48.6.4. Kerberos and PAM
        5. 48.6.5. Configuring a Kerberos 5 Server
        6. 48.6.6. Configuring a Kerberos 5 Client
        7. 48.6.7. Domain-to-Realm Mapping
        8. 48.6.8. Setting Up Secondary KDCs
        9. 48.6.9. Setting Up Cross Realm Authentication
        10. 48.6.10. Additional Resources
          1. 48.6.10.1. Installed Documentation
          2. 48.6.10.2. Useful Websites
      7. 48.7. Virtual Private Networks (VPNs)
        1. 48.7.1. How Does a VPN Work?
        2. 48.7.2. VPNs and Red Hat Enterprise Linux
        3. 48.7.3. IPsec
        4. 48.7.4. Creating an IPsec Connection
        5. 48.7.5. IPsec Installation
        6. 48.7.6. IPsec Host-to-Host Configuration
          1. 48.7.6.1. Host-to-Host Connection
          2. 48.7.6.2. Manual IPsec Host-to-Host Configuration
            1. 48.7.6.2.1. The Racoon Configuration File
        7. 48.7.7. IPsec Network-to-Network Configuration
          1. 48.7.7.1. Network-to-Network (VPN) Connection
          2. 48.7.7.2. Manual IPsec Network-to-Network Configuration
        8. 48.7.8. Starting and Stopping an IPsec Connection
      8. 48.8. Firewalls
        1. 48.8.1. Netfilter and IPTables
          1. 48.8.1.1. IPTables Overview
        2. 48.8.2. Basic Firewall Configuration
          1. 48.8.2.1. Security Level Configuration Tool
          2. 48.8.2.2. Enabling and Disabling the Firewall
          3. 48.8.2.3. Trusted Services
          4. 48.8.2.4. Other Ports
          5. 48.8.2.5. Saving the Settings
          6. 48.8.2.6. Activating the IPTables Service
        3. 48.8.3. Using IPTables
          1. 48.8.3.1. IPTables Command Syntax
          2. 48.8.3.2. Basic Firewall Policies
          3. 48.8.3.3. Saving and Restoring IPTables Rules
        4. 48.8.4. Common IPTables Filtering
        5. 48.8.5. FORWARD and NAT Rules
          1. 48.8.5.1. Postrouting and IP Masquerading
          2. 48.8.5.2. Prerouting
          3. 48.8.5.3. DMZs and IPTables
        6. 48.8.6. Malicious Software and Spoofed IP Addresses
        7. 48.8.7. IPTables and Connection Tracking
        8. 48.8.8. IPv6
        9. 48.8.9. Additional Resources
          1. 48.8.9.1. Installed Documentation
          2. 48.8.9.2. Useful Websites
          3. 48.8.9.3. Related Documentation
      9. 48.9. IPTables
        1. 48.9.1. Packet Filtering
        2. 48.9.2. Differences Between IPTables and IPChains
        3. 48.9.3. Command Options for IPTables
          1. 48.9.3.1. Structure of IPTables Command Options
          2. 48.9.3.2. Command Options
          3. 48.9.3.3. IPTables Parameter Options
          4. 48.9.3.4. IPTables Match Options
            1. 48.9.3.4.1. TCP Protocol
            2. 48.9.3.4.2. UDP Protocol
            3. 48.9.3.4.3. ICMP Protocol
            4. 48.9.3.4.4. Additional Match Option Modules
          5. 48.9.3.5. Target Options
          6. 48.9.3.6. Listing Options
        4. 48.9.4. Saving IPTables Rules
        5. 48.9.5. IPTables Control Scripts
          1. 48.9.5.1. IPTables Control Scripts Configuration File
        6. 48.9.6. IPTables and IPv6
        7. 48.9.7. Additional Resources
          1. 48.9.7.1. Installed Documentation
          2. 48.9.7.2. Useful Websites
    3. 49. Security and SELinux
      1. 49.1. Access Control Mechanisms (ACMs)
        1. 49.1.1. Discretionary Access Control (DAC)
        2. 49.1.2. Access Control Lists (ACLs)
        3. 49.1.3. Mandatory Access Control (MAC)
        4. 49.1.4. Role-based Access Control (RBAC)
        5. 49.1.5. Multi-Level Security (MLS)
        6. 49.1.6. Multi-Category Security (MCS)
      2. 49.2. Introduction to SELinux
        1. 49.2.1. SELinux Overview
        2. 49.2.2. Files Related to SELinux
          1. 49.2.2.1. The SELinux Pseudo-File System
          2. 49.2.2.2. SELinux Configuration Files
            1. 49.2.2.2.1. The /etc/sysconfig/selinux Configuration File
            2. 49.2.2.2.2. The /etc/selinux/ Directory
          3. 49.2.2.3. SELinux Utilities
        3. 49.2.3. Additional Resources
          1. 49.2.3.1. Installed Documentation
          2. 49.2.3.2. Useful Websites
      3. 49.3. Brief Background and History of SELinux
      4. 49.4. Multi-Category Security (MCS)
        1. 49.4.1. Introduction
          1. 49.4.1.1. What is Multi-Category Security?
        2. 49.4.2. Applications for Multi-Category Security
        3. 49.4.3. SELinux Security Contexts
      5. 49.5. Getting Started with Multi-Category Security (MCS)
        1. 49.5.1. Introduction
        2. 49.5.2. Comparing SELinux and Standard Linux User Identities
        3. 49.5.3. Configuring Categories
        4. 49.5.4. Assigning Categories to Users
        5. 49.5.5. Assigning Categories to Files
      6. 49.6. Multi-Level Security (MLS)
        1. 49.6.1. Why Multi-Level?
          1. 49.6.1.1. The Bell-La Padula Model (BLP)
          2. 49.6.1.2. MLS and System Privileges
        2. 49.6.2. Security Levels, Objects and Subjects
        3. 49.6.3. MLS Policy
        4. 49.6.4. Enabling MLS in SELinux
        5. 49.6.5. LSPP Certification
      7. 49.7. SELinux Policy Overview
        1. 49.7.1. What is the SELinux Policy?
          1. 49.7.1.1. SELinux Types
            1. 49.7.1.1.1. Using Policy Rules to Define Type Access
          2. 49.7.1.2. SELinux and Mandatory Access Control
        2. 49.7.2. Where is the Policy?
          1. 49.7.2.1. Binary Tree Files
          2. 49.7.2.2. Source Tree Files
        3. 49.7.3. The Role of Policy in the Boot Process
        4. 49.7.4. Object Classes and Permissions
      8. 49.8. Targeted Policy Overview
        1. 49.8.1. What is the Targeted Policy?
        2. 49.8.2. Files and Directories of the Targeted Policy
        3. 49.8.3. Understanding the Users and Roles in the Targeted Policy
    4. 50. Working With SELinux
      1. 50.1. End User Control of SELinux
        1. 50.1.1. Moving and Copying Files
        2. 50.1.2. Checking the Security Context of a Process, User, or File Object
        3. 50.1.3. Relabeling a File or Directory
        4. 50.1.4. Creating Archives That Retain Security Contexts
      2. 50.2. Administrator Control of SELinux
        1. 50.2.1. Viewing the Status of SELinux
        2. 50.2.2. Relabeling a File System
        3. 50.2.3. Managing NFS Home Directories
        4. 50.2.4. Granting Access to a Directory or a Tree
        5. 50.2.5. Backing Up and Restoring the System
        6. 50.2.6. Enabling or Disabling Enforcement
        7. 50.2.7. Enable or Disable SELinux
        8. 50.2.8. Changing the Policy
        9. 50.2.9. Specifying the Security Context of Entire File Systems
        10. 50.2.10. Changing the Security Category of a File or User
        11. 50.2.11. Running a Command in a Specific Security Context
        12. 50.2.12. Useful Commands for Scripts
        13. 50.2.13. Changing to a Different Role
        14. 50.2.14. When to Reboot
      3. 50.3. Analyst Control of SELinux
        1. 50.3.1. Enabling Kernel Auditing
        2. 50.3.2. Dumping and Viewing Logs
    5. 51. Customizing SELinux Policy
      1. 51.1. Introduction
        1. 51.1.1. Modular Policy
          1. 51.1.1.1. Listing Policy Modules
      2. 51.2. Building a Local Policy Module
        1. 51.2.1. Using audit2allow to Build a Local Policy Module
        2. 51.2.2. Analyzing the Type Enforcement (TE) File
        3. 51.2.3. Loading the Policy Package
    6. 52. References
  10. VIII. Red Hat Training And Certification
    1. 53. Red Hat Training and Certification
      1. 53.1. Three Ways to Train
      2. 53.2. Microsoft Certified Professional Resource Center
    2. 54. Certification Tracks
      1. 54.1. Free Pre-assessment tests
    3. 55. RH033: Red Hat Linux Essentials
      1. 55.1. Course Description
        1. 55.1.1. Prerequisites
        2. 55.1.2. Goal
        3. 55.1.3. Audience
        4. 55.1.4. Course Objectives
        5. 55.1.5. Follow-on Courses
    4. 56. RH035: Red Hat Linux Essentials for Windows Professionals
      1. 56.1. Course Description
        1. 56.1.1. Prerequisites
        2. 56.1.2. Goal
        3. 56.1.3. Audience
        4. 56.1.4. Course Objectives
        5. 56.1.5. Follow-on Courses
    5. 57. RH133: Red Hat Linux System Administration and Red Hat Certified Technician (RHCT) Certification
      1. 57.1. Course Description
        1. 57.1.1. Prerequisites
        2. 57.1.2. Goal
        3. 57.1.3. Audience
        4. 57.1.4. Course Objectives
        5. 57.1.5. Follow-on Courses
    6. 58. RH202 RHCT EXAM - The fastest growing credential in all of Linux.
      1. 58.1. Course Description
        1. 58.1.1. Prerequisites
    7. 59. RH253 Red Hat Linux Networking and Security Administration
      1. 59.1. Course Description
        1. 59.1.1. Prerequisites
        2. 59.1.2. Goal
        3. 59.1.3. Audience
        4. 59.1.4. Course Objectives
        5. 59.1.5. Follow-on Courses
    8. 60. RH300: RHCE Rapid track course (and RHCE exam)
      1. 60.1. Course Description
        1. 60.1.1. Prerequisites
        2. 60.1.2. Goal
        3. 60.1.3. Audience
        4. 60.1.4. Course Objectives
        5. 60.1.5. Follow-on Courses
    9. 61. RH302 RHCE EXAM
      1. 61.1. Course Description
        1. 61.1.1. Prerequisites
        2. 61.1.2. Content
    10. 62. RHS333: RED HAT enterprise security: network services
      1. 62.1. Course Description
        1. 62.1.1. Prerequisites
        2. 62.1.2. Goal
        3. 62.1.3. Audience
        4. 62.1.4. Course Objectives
        5. 62.1.5. Follow-on Courses
    11. 63. RH401: Red Hat Enterprise Deployment and systems management
      1. 63.1. Course Description
        1. 63.1.1. Prerequisites
        2. 63.1.2. Goal
        3. 63.1.3. Audience
        4. 63.1.4. Course Objectives
        5. 63.1.5. Follow-on Courses
    12. 64. RH423: Red Hat Enterprise Directory services and authentication
      1. 64.1. Course Description
        1. 64.1.1. Prerequisites
        2. 64.1.2. Goal
        3. 64.1.3. Audience
        4. 64.1.4. Course Objectives
        5. 64.1.5. Follow-on Courses
    13. 65. SELinux Courses
      1. 65.1. RHS427: Introduction to SELinux and Red Hat Targeted Policy
        1. 65.1.1. Audience
        2. 65.1.2. Course Summary
      2. 65.2. RHS429: Red Hat Enterprise SELinux Policy Administration
    14. 66. RH436: Red Hat Enterprise storage management
      1. 66.1. Course Description
        1. 66.1.1. Prerequisites
        2. 66.1.2. Goal
        3. 66.1.3. Audience
        4. 66.1.4. Course Objectives
        5. 66.1.5. Follow-on Courses
    15. 67. RH442: Red Hat Enterprise system monitoring and performance tuning
      1. 67.1. Course Description
        1. 67.1.1. Prerequisites
        2. 67.1.2. Goal
        3. 67.1.3. Audience
        4. 67.1.4. Course Objectives
        5. 67.1.5. Follow-on Courses
    16. 68. Red Hat Enterprise Linux Developer Courses
      1. 68.1. RHD143: Red Hat Linux Programming Essentials
      2. 68.2. RHD221 Red Hat Linux Device Drivers
      3. 68.3. RHD236 Red Hat Linux Kernel Internals
      4. 68.4. RHD256 Red Hat Linux Application Development and Porting
    17. 69. JBoss Courses
      1. 69.1. RHD161 JBoss and EJB3 for Java
        1. 69.1.1. Prerequisites
      2. 69.2. RHD163 JBoss for Web Developers
        1. 69.2.1. Prerequisites
      3. 69.3. RHD167: JBOSS - HIBERNATE ESSENTIALS
        1. 69.3.1. Prerequisites
        2. 69.3.2. Course Summary
      4. 69.4. RHD267: JBOSS - ADVANCED HIBERNATE
        1. 69.4.1. Prerequisites
      5. 69.5. RHD261:JBOSS for advanced J2EE developers
        1. 69.5.1. Prerequisites
      6. 69.6. RH336: JBOSS for Administrators
        1. 69.6.1. Prerequisites
        2. 69.6.2. Course Summary
      7. 69.7. RHD439: JBoss Clustering
        1. 69.7.1. Prerequisites
      8. 69.8. RHD449: JBoss jBPM
        1. 69.8.1. Description
        2. 69.8.2. Prerequisites
      9. 69.9. RHD451 JBoss Rules
        1. 69.9.1. Prerequisites
  11. A. Revision History
  12. B. Colophon
  13. Legal Notice

48.5.5.3. Related Books

  • Hacking Linux Exposed by Brian Hatch, James Lee, and George Kurtz; Osbourne/McGraw-Hill — An excellent security resource with information about TCP Wrappers and xinetd.
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