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  5. Deployment Guide
  6. 22.19.2. Useful Websites
  1. Deployment Guide
  2. I. Basic System Configuration
    1. 1. Keyboard Configuration
      1. 1.1. Changing the Keyboard Layout
      2. 1.2. Adding the Keyboard Layout Indicator
      3. 1.3. Setting Up a Typing Break
    2. 2. Date and Time Configuration
      1. 2.1. Date/Time Properties Tool
        1. 2.1.1. Date and Time Properties
        2. 2.1.2. Network Time Protocol Properties
        3. 2.1.3. Time Zone Properties
      2. 2.2. Command Line Configuration
        1. 2.2.1. Date and Time Setup
        2. 2.2.2. Network Time Protocol Setup
    3. 3. Managing Users and Groups
      1. 3.1. What Users and Groups Are
      2. 3.2. Managing Users via the User Manager Application
        1. 3.2.1. Viewing Users
        2. 3.2.2. Adding a New User
        3. 3.2.3. Modifying User Properties
      3. 3.3. Managing Groups via the User Manager Application
        1. 3.3.1. Viewing Groups
        2. 3.3.2. Adding a New Group
        3. 3.3.3. Modifying Group Properties
      4. 3.4. Managing Users via Command-Line Tools
        1. 3.4.1. Creating Users
        2. 3.4.2. Attaching New Users to Groups
        3. 3.4.3. Updating Users' Authentication
        4. 3.4.4. Modifying User Settings
        5. 3.4.5. Deleting Users
        6. 3.4.6. Displaying Comprehensive User Information
      5. 3.5. Managing Groups via Command-Line Tools
        1. 3.5.1. Creating Groups
        2. 3.5.2. Attaching Users to Groups
        3. 3.5.3. Updating Group Authentication
        4. 3.5.4. Modifying Group Settings
        5. 3.5.5. Deleting Groups
      6. 3.6. Additional Resources
        1. 3.6.1. Installed Documentation
    4. 4. Gaining Privileges
      1. 4.1. The su Command
      2. 4.2. The sudo Command
      3. 4.3. Additional Resources
    5. 5. Console Access
      1. 5.1. Disabling Console Program Access for Non-root Users
      2. 5.2. Disabling Rebooting Using Ctrl+Alt+Del
  3. II. Subscription and Support
    1. 6. Registering the System and Managing Subscriptions
      1. 6.1. Registering the System and Attaching Subscriptions
      2. 6.2. Managing Software Repositories
      3. 6.3. Removing Subscriptions
      4. 6.4. Additional Resources
    2. 7. Accessing Support Using the Red Hat Support Tool
      1. 7.1. Installing the Red Hat Support Tool
      2. 7.2. Registering the Red Hat Support Tool Using the Command Line
      3. 7.3. Using the Red Hat Support Tool in Interactive Shell Mode
      4. 7.4. Configuring the Red Hat Support Tool
        1. 7.4.1. Saving Settings to the Configuration Files
      5. 7.5. Opening and Updating Support Cases Using Interactive Mode
      6. 7.6. Viewing Support Cases on the Command Line
      7. 7.7. Additional Resources
  4. III. Installing and Managing Software
    1. 8. Yum
      1. 8.1. Checking For and Updating Packages
        1. 8.1.1. Checking For Updates
        2. 8.1.2. Updating Packages
        3. 8.1.3. Preserving Configuration File Changes
        4. 8.1.4. Upgrading the System Off-line with ISO and Yum
      2. 8.2. Packages and Package Groups
        1. 8.2.1. Searching Packages
        2. 8.2.2. Listing Packages
        3. 8.2.3. Displaying Package Information
        4. 8.2.4. Installing Packages
        5. 8.2.5. Removing Packages
      3. 8.3. Working with Transaction History
        1. 8.3.1. Listing Transactions
        2. 8.3.2. Examining Transactions
        3. 8.3.3. Reverting and Repeating Transactions
        4. 8.3.4. Completing Transactions
        5. 8.3.5. Starting New Transaction History
      4. 8.4. Configuring Yum and Yum Repositories
        1. 8.4.1. Setting [main] Options
        2. 8.4.2. Setting [repository] Options
        3. 8.4.3. Using Yum Variables
        4. 8.4.4. Viewing the Current Configuration
        5. 8.4.5. Adding, Enabling, and Disabling a Yum Repository
        6. 8.4.6. Creating a Yum Repository
        7. 8.4.7. Working with Yum Cache
        8. 8.4.8. Adding the Optional and Supplementary Repositories
      5. 8.5. Yum Plug-ins
        1. 8.5.1. Enabling, Configuring, and Disabling Yum Plug-ins
        2. 8.5.2. Installing Additional Yum Plug-ins
        3. 8.5.3. Plug-in Descriptions
      6. 8.6. Additional Resources
    2. 9. PackageKit
      1. 9.1. Updating Packages with Software Update
      2. 9.2. Using Add/Remove Software
        1. 9.2.1. Refreshing Software Sources (Yum Repositories)
        2. 9.2.2. Finding Packages with Filters
        3. 9.2.3. Installing and Removing Packages (and Dependencies)
        4. 9.2.4. Installing and Removing Package Groups
        5. 9.2.5. Viewing the Transaction Log
      3. 9.3. PackageKit Architecture
      4. 9.4. Additional Resources
  5. IV. Networking
    1. 10. NetworkManager
      1. 10.1. The NetworkManager Daemon
      2. 10.2. Interacting with NetworkManager
        1. 10.2.1. Connecting to a Network
        2. 10.2.2. Configuring New and Editing Existing Connections
        3. 10.2.3. Connecting to a Network Automatically
        4. 10.2.4. User and System Connections
      3. 10.3. Establishing Connections
        1. 10.3.1. Establishing a Wired (Ethernet) Connection
        2. 10.3.2. Establishing a Wireless Connection
        3. 10.3.3. Establishing a Mobile Broadband Connection
        4. 10.3.4. Establishing a VPN Connection
        5. 10.3.5. Establishing a DSL Connection
        6. 10.3.6. Establishing a Bond Connection
        7. 10.3.7. Establishing a VLAN Connection
        8. 10.3.8. Establishing an IP-over-InfiniBand (IPoIB) Connection
        9. 10.3.9. Configuring Connection Settings
          1. 10.3.9.1. Configuring 802.1X Security
            1. 10.3.9.1.1. Configuring TLS (Transport Layer Security) Settings
            2. 10.3.9.1.2. Configuring Tunneled TLS Settings
            3. 10.3.9.1.3. Configuring Protected EAP (PEAP) Settings
          2. 10.3.9.2. Configuring Wireless Security
          3. 10.3.9.3. Configuring PPP (Point-to-Point) Settings
          4. 10.3.9.4. Configuring IPv4 Settings
          5. 10.3.9.5. Configuring IPv6 Settings
          6. 10.3.9.6. Configuring Routes
    2. 11. Network Interfaces
      1. 11.1. Network Configuration Files
        1. 11.1.1. Setting the Host Name
      2. 11.2. Interface Configuration Files
        1. 11.2.1. Ethernet Interfaces
        2. 11.2.2. Specific ifcfg Options for Linux on System z
        3. 11.2.3. Required ifcfg Options for Linux on System z
        4. 11.2.4. Channel Bonding Interfaces
          1. 11.2.4.1. Check if Bonding Kernel Module is Installed
          2. 11.2.4.2. Create a Channel Bonding Interface
            1. 11.2.4.2.1. Creating Multiple Bonds
        5. 11.2.5. Configuring a VLAN over a Bond
        6. 11.2.6. Network Bridge
          1. 11.2.6.1. Network Bridge with Bond
          2. 11.2.6.2. Network Bridge with Bonded VLAN
        7. 11.2.7. Setting Up 802.1Q VLAN Tagging
        8. 11.2.8. Alias and Clone Files
        9. 11.2.9. Dialup Interfaces
        10. 11.2.10. Other Interfaces
      3. 11.3. Interface Control Scripts
      4. 11.4. Static Routes and the Default Gateway
      5. 11.5. Configuring Static Routes in ifcfg files
        1. 11.5.1. Static Routes Using the IP Command Arguments Format
        2. 11.5.2. Network/Netmask Directives Format
      6. 11.6. Configuring IPv6 Tokenized Interface Identifiers
      7. 11.7. Network Function Files
      8. 11.8. Ethtool
      9. 11.9. Configuring netconsole
      10. 11.10. Additional Resources
  6. V. Infrastructure Services
    1. 12. Services and Daemons
      1. 12.1. Configuring the Default Runlevel
      2. 12.2. Configuring the Services
        1. 12.2.1. Using the Service Configuration Utility
          1. 12.2.1.1. Enabling and Disabling a Service
          2. 12.2.1.2. Starting, Restarting, and Stopping a Service
          3. 12.2.1.3. Selecting Runlevels
        2. 12.2.2. Using the ntsysv Utility
          1. 12.2.2.1. Enabling and Disabling a Service
          2. 12.2.2.2. Selecting Runlevels
        3. 12.2.3. Using the chkconfig Utility
          1. 12.2.3.1. Listing the Services
          2. 12.2.3.2. Enabling a Service
          3. 12.2.3.3. Disabling a Service
      3. 12.3. Running Services
        1. 12.3.1. Determining the Service Status
        2. 12.3.2. Starting a Service
        3. 12.3.3. Stopping a Service
        4. 12.3.4. Restarting a Service
      4. 12.4. Additional Resources
        1. 12.4.1. Installed Documentation
        2. 12.4.2. Related Books
    2. 13. Configuring Authentication
      1. 13.1. Configuring System Authentication
        1. 13.1.1. Launching the Authentication Configuration Tool UI
        2. 13.1.2. Selecting the Identity Store for Authentication
          1. 13.1.2.1. Configuring LDAP Authentication
          2. 13.1.2.2. Configuring NIS Authentication
          3. 13.1.2.3. Configuring Winbind Authentication
          4. 13.1.2.4. Using Kerberos with LDAP or NIS Authentication
        3. 13.1.3. Configuring Alternative Authentication Features
          1. 13.1.3.1. Using Fingerprint Authentication
          2. 13.1.3.2. Setting Local Authentication Parameters
          3. 13.1.3.3. Enabling Smart Card Authentication
          4. 13.1.3.4. Creating User Home Directories
        4. 13.1.4. Configuring Authentication from the Command Line
          1. 13.1.4.1. Tips for Using authconfig
          2. 13.1.4.2. Configuring LDAP User Stores
          3. 13.1.4.3. Configuring NIS User Stores
          4. 13.1.4.4. Configuring Winbind User Stores
          5. 13.1.4.5. Configuring Kerberos Authentication
          6. 13.1.4.6. Configuring Local Authentication Settings
          7. 13.1.4.7. Configuring Fingerprint Authentication
          8. 13.1.4.8. Configuring Smart Card Authentication
          9. 13.1.4.9. Managing Kickstart and Configuration Files
        5. 13.1.5. Using Custom Home Directories
      2. 13.2. Using and Caching Credentials with SSSD
        1. 13.2.1. About SSSD
        2. 13.2.2. Setting up the sssd.conf File
          1. 13.2.2.1. Creating the sssd.conf File
          2. 13.2.2.2. Using a Custom Configuration File
        3. 13.2.3. Starting and Stopping SSSD
        4. 13.2.4. SSSD and System Services
        5. 13.2.5. Configuring Services: NSS
        6. 13.2.6. Configuring Services: PAM
        7. 13.2.7. Configuring Services: autofs
        8. 13.2.8. Configuring Services: sudo
        9. 13.2.9. Configuring Services: OpenSSH and Cached Keys
        10. 13.2.10. SSSD and Identity Providers (Domains)
        11. 13.2.11. Creating Domains: LDAP
        12. 13.2.12. Creating Domains: Identity Management (IdM)
        13. 13.2.13. Creating Domains: Active Directory
        14. 13.2.14. Configuring Domains: Active Directory as an LDAP Provider (Alternative)
        15. 13.2.15. Domain Options: Setting Username Formats
        16. 13.2.16. Domain Options: Enabling Offline Authentication
        17. 13.2.17. Domain Options: Setting Password Expirations
        18. 13.2.18. Domain Options: Using DNS Service Discovery
        19. 13.2.19. Domain Options: Using IP Addresses in Certificate Subject Names (LDAP Only)
        20. 13.2.20. Creating Domains: Proxy
        21. 13.2.21. Creating Domains: Kerberos Authentication
        22. 13.2.22. Creating Domains: Access Control
        23. 13.2.23. Creating Domains: Primary Server and Backup Servers
        24. 13.2.24. Installing SSSD Utilities
        25. 13.2.25. SSSD and UID and GID Numbers
        26. 13.2.26. Creating Local System Users
        27. 13.2.27. Seeding Users into the SSSD Cache During Kickstart
        28. 13.2.28. Managing the SSSD Cache
        29. 13.2.29. Downgrading SSSD
        30. 13.2.30. Using NSCD with SSSD
        31. 13.2.31. Troubleshooting SSSD
    3. 14. OpenSSH
      1. 14.1. The SSH Protocol
        1. 14.1.1. Why Use SSH?
        2. 14.1.2. Main Features
        3. 14.1.3. Protocol Versions
        4. 14.1.4. Event Sequence of an SSH Connection
          1. 14.1.4.1. Transport Layer
          2. 14.1.4.2. Authentication
          3. 14.1.4.3. Channels
      2. 14.2. Configuring OpenSSH
        1. 14.2.1. Configuration Files
        2. 14.2.2. Starting an OpenSSH Server
        3. 14.2.3. Requiring SSH for Remote Connections
        4. 14.2.4. Using Key-Based Authentication
          1. 14.2.4.1. Generating Key Pairs
          2. 14.2.4.2. Configuring ssh-agent
          3. 14.2.4.3. Multiple required methods of authentication for sshd
      3. 14.3. Using OpenSSH Certificate Authentication
        1. 14.3.1. Introduction to SSH Certificates
        2. 14.3.2. Support for SSH Certificates
        3. 14.3.3. Creating SSH CA Certificate Signing Keys
        4. 14.3.4. Distributing and Trusting SSH CA Public Keys
        5. 14.3.5. Creating SSH Certificates
          1. 14.3.5.1. Creating SSH Certificates to Authenticate Hosts
          2. 14.3.5.2. Creating SSH Certificates for Authenticating Users
        6. 14.3.6. Signing an SSH Certificate Using a PKCS#11 Token
        7. 14.3.7. Viewing an SSH CA Certificate
        8. 14.3.8. Revoking an SSH CA Certificate
      4. 14.4. OpenSSH Clients
        1. 14.4.1. Using the ssh Utility
        2. 14.4.2. Using the scp Utility
        3. 14.4.3. Using the sftp Utility
      5. 14.5. More Than a Secure Shell
        1. 14.5.1. X11 Forwarding
        2. 14.5.2. Port Forwarding
      6. 14.6. Additional Resources
        1. 14.6.1. Installed Documentation
        2. 14.6.2. Useful Websites
    4. 15. TigerVNC
      1. 15.1. VNC Server
        1. 15.1.1. Installing VNC Server
        2. 15.1.2. Configuring VNC Server
        3. 15.1.3. Starting VNC Server
        4. 15.1.4. Terminating a VNC Session
      2. 15.2. Sharing an Existing Desktop
      3. 15.3. Using a VNC Viewer
        1. 15.3.1. Installing the VNC Viewer
        2. 15.3.2. Connecting to a VNC Server
          1. 15.3.2.1. Configuring the Firewall for VNC
        3. 15.3.3. Connecting to VNC Server Using SSH
      4. 15.4. Additional Resources
  7. VI. Servers
    1. 16. DHCP Servers
      1. 16.1. Why Use DHCP?
      2. 16.2. Configuring a DHCPv4 Server
        1. 16.2.1. Configuration File
        2. 16.2.2. Lease Database
        3. 16.2.3. Starting and Stopping the Server
        4. 16.2.4. DHCP Relay Agent
      3. 16.3. Configuring a DHCPv4 Client
      4. 16.4. Configuring a Multihomed DHCP Server
        1. 16.4.1. Host Configuration
      5. 16.5. DHCP for IPv6 (DHCPv6)
        1. 16.5.1. Configuring a DHCPv6 Server
        2. 16.5.2. Configuring a DHCPv6 Client
      6. 16.6. Additional Resources
        1. 16.6.1. Installed Documentation
    2. 17. DNS Servers
      1. 17.1. Introduction to DNS
        1. 17.1.1. Nameserver Zones
        2. 17.1.2. Nameserver Types
        3. 17.1.3. BIND as a Nameserver
      2. 17.2. BIND
        1. 17.2.1. Configuring the named Service
          1. 17.2.1.1. Common Statement Types
          2. 17.2.1.2. Other Statement Types
          3. 17.2.1.3. Comment Tags
        2. 17.2.2. Editing Zone Files
          1. 17.2.2.1. Common Directives
          2. 17.2.2.2. Common Resource Records
          3. 17.2.2.3. Comment Tags
          4. 17.2.2.4. Example Usage
            1. 17.2.2.4.1. A Simple Zone File
            2. 17.2.2.4.2. A Reverse Name Resolution Zone File
        3. 17.2.3. Using the rndc Utility
          1. 17.2.3.1. Configuring the Utility
          2. 17.2.3.2. Checking the Service Status
          3. 17.2.3.3. Reloading the Configuration and Zones
          4. 17.2.3.4. Updating Zone Keys
          5. 17.2.3.5. Enabling the DNSSEC Validation
          6. 17.2.3.6. Enabling the Query Logging
        4. 17.2.4. Using the dig Utility
          1. 17.2.4.1. Looking Up a Nameserver
          2. 17.2.4.2. Looking Up an IP Address
          3. 17.2.4.3. Looking Up a Hostname
        5. 17.2.5. Advanced Features of BIND
          1. 17.2.5.1. Multiple Views
          2. 17.2.5.2. Incremental Zone Transfers (IXFR)
          3. 17.2.5.3. Transaction SIGnatures (TSIG)
          4. 17.2.5.4. DNS Security Extensions (DNSSEC)
          5. 17.2.5.5. Internet Protocol version 6 (IPv6)
        6. 17.2.6. Common Mistakes to Avoid
        7. 17.2.7. Additional Resources
          1. 17.2.7.1. Installed Documentation
          2. 17.2.7.2. Useful Websites
          3. 17.2.7.3. Related Books
    3. 18. Web Servers
      1. 18.1. The Apache HTTP Server
        1. 18.1.1. New Features
        2. 18.1.2. Notable Changes
        3. 18.1.3. Updating the Configuration
        4. 18.1.4. Running the httpd Service
          1. 18.1.4.1. Starting the Service
          2. 18.1.4.2. Stopping the Service
          3. 18.1.4.3. Restarting the Service
          4. 18.1.4.4. Verifying the Service Status
        5. 18.1.5. Editing the Configuration Files
          1. 18.1.5.1. Common httpd.conf Directives
          2. 18.1.5.2. Common ssl.conf Directives
          3. 18.1.5.3. Common Multi-Processing Module Directives
        6. 18.1.6. Working with Modules
          1. 18.1.6.1. Loading a Module
          2. 18.1.6.2. Writing a Module
        7. 18.1.7. Setting Up Virtual Hosts
        8. 18.1.8. Setting Up an SSL Server
          1. 18.1.8.1. An Overview of Certificates and Security
        9. 18.1.9. Enabling the mod_ssl Module
          1. 18.1.9.1. Enabling and Disabling SSL and TLS in mod_ssl
        10. 18.1.10. Enabling the mod_nss Module
          1. 18.1.10.1. Enabling and Disabling SSL and TLS in mod_nss
        11. 18.1.11. Using an Existing Key and Certificate
        12. 18.1.12. Generating a New Key and Certificate
        13. 18.1.13. Configure the Firewall for HTTP and HTTPS Using the Command Line
          1. 18.1.13.1. Checking Network Access for Incoming HTTPS and HTTPS Using the Command Line
        14. 18.1.14. Additional Resources
    4. 19. Mail Servers
      1. 19.1. Email Protocols
        1. 19.1.1. Mail Transport Protocols
          1. 19.1.1.1. SMTP
        2. 19.1.2. Mail Access Protocols
          1. 19.1.2.1. POP
          2. 19.1.2.2. IMAP
          3. 19.1.2.3. Dovecot
      2. 19.2. Email Program Classifications
        1. 19.2.1. Mail Transport Agent
        2. 19.2.2. Mail Delivery Agent
        3. 19.2.3. Mail User Agent
      3. 19.3. Mail Transport Agents
        1. 19.3.1. Postfix
          1. 19.3.1.1. The Default Postfix Installation
          2. 19.3.1.2. Basic Postfix Configuration
            1. 19.3.1.2.1. Configuring Postfix to Use Transport Layer Security
          3. 19.3.1.3. Using Postfix with LDAP
            1. 19.3.1.3.1. The /etc/aliases lookup example
        2. 19.3.2. Sendmail
          1. 19.3.2.1. Purpose and Limitations
          2. 19.3.2.2. The Default Sendmail Installation
          3. 19.3.2.3. Common Sendmail Configuration Changes
          4. 19.3.2.4. Masquerading
          5. 19.3.2.5. Stopping Spam
          6. 19.3.2.6. Using Sendmail with LDAP
        3. 19.3.3. Fetchmail
          1. 19.3.3.1. Fetchmail Configuration Options
          2. 19.3.3.2. Global Options
          3. 19.3.3.3. Server Options
          4. 19.3.3.4. User Options
          5. 19.3.3.5. Fetchmail Command Options
          6. 19.3.3.6. Informational or Debugging Options
          7. 19.3.3.7. Special Options
        4. 19.3.4. Mail Transport Agent (MTA) Configuration
      4. 19.4. Mail Delivery Agents
        1. 19.4.1. Procmail Configuration
        2. 19.4.2. Procmail Recipes
          1. 19.4.2.1. Delivering vs. Non-Delivering Recipes
          2. 19.4.2.2. Flags
          3. 19.4.2.3. Specifying a Local Lockfile
          4. 19.4.2.4. Special Conditions and Actions
          5. 19.4.2.5. Recipe Examples
          6. 19.4.2.6. Spam Filters
      5. 19.5. Mail User Agents
        1. 19.5.1. Securing Communication
          1. 19.5.1.1. Secure Email Clients
          2. 19.5.1.2. Securing Email Client Communications
      6. 19.6. Additional Resources
        1. 19.6.1. Installed Documentation
        2. 19.6.2. Online Documentation
        3. 19.6.3. Related Books
    5. 20. Directory Servers
      1. 20.1. OpenLDAP
        1. 20.1.1. Introduction to LDAP
          1. 20.1.1.1. LDAP Terminology
          2. 20.1.1.2. OpenLDAP Features
          3. 20.1.1.3. OpenLDAP Server Setup
        2. 20.1.2. Installing the OpenLDAP Suite
          1. 20.1.2.1. Overview of OpenLDAP Server Utilities
          2. 20.1.2.2. Overview of OpenLDAP Client Utilities
          3. 20.1.2.3. Overview of Common LDAP Client Applications
        3. 20.1.3. Configuring an OpenLDAP Server
          1. 20.1.3.1. Changing the Global Configuration
          2. 20.1.3.2. Changing the Database-Specific Configuration
          3. 20.1.3.3. Extending Schema
        4. 20.1.4. Running an OpenLDAP Server
          1. 20.1.4.1. Starting the Service
          2. 20.1.4.2. Stopping the Service
          3. 20.1.4.3. Restarting the Service
          4. 20.1.4.4. Checking the Service Status
        5. 20.1.5. Configuring a System to Authenticate Using OpenLDAP
          1. 20.1.5.1. Migrating Old Authentication Information to LDAP Format
        6. 20.1.6. Additional Resources
          1. 20.1.6.1. Installed Documentation
          2. 20.1.6.2. Useful Websites
          3. 20.1.6.3. Related Books
    6. 21. File and Print Servers
      1. 21.1. Samba
        1. 21.1.1. Introduction to Samba
        2. 21.1.2. Samba Daemons and Related Services
        3. 21.1.3. Connecting to a Samba Share
          1. 21.1.3.1. Mounting the Share
        4. 21.1.4. Configuring a Samba Server
          1. 21.1.4.1. Graphical Configuration
          2. 21.1.4.2. Command-Line Configuration
          3. 21.1.4.3. Encrypted Passwords
        5. 21.1.5. Starting and Stopping Samba
        6. 21.1.6. Samba Server Types and the smb.conf File
          1. 21.1.6.1. Stand-alone Server
          2. 21.1.6.2. Domain Member Server
          3. 21.1.6.3. Domain Controller
        7. 21.1.7. Samba Security Modes
          1. 21.1.7.1. User-Level Security
          2. 21.1.7.2. Share-Level Security
        8. 21.1.8. Samba Account Information Databases
        9. 21.1.9. Samba Network Browsing
          1. 21.1.9.1. Domain Browsing
          2. 21.1.9.2. WINS (Windows Internet Name Server)
        10. 21.1.10. Samba with CUPS Printing Support
          1. 21.1.10.1. Simple smb.conf Settings
        11. 21.1.11. Samba Distribution Programs
        12. 21.1.12. Additional Resources
      2. 21.2. FTP
        1. 21.2.1. The File Transfer Protocol
        2. 21.2.2. The vsftpd Server
          1. 21.2.2.1. Starting and Stopping vsftpd
          2. 21.2.2.2. Starting Multiple Copies of vsftpd
          3. 21.2.2.3. Encrypting vsftpd Connections Using TLS
          4. 21.2.2.4. SELinux Policy for vsftpd
          5. 21.2.2.5. Files Installed with vsftpd
          6. 21.2.2.6. vsftpd Configuration Options
            1. 21.2.2.6.1. Daemon Options
            2. 21.2.2.6.2. Log In Options and Access Controls
            3. 21.2.2.6.3. Anonymous User Options
            4. 21.2.2.6.4. Local-User Options
            5. 21.2.2.6.5. Directory Options
            6. 21.2.2.6.6. File Transfer Options
            7. 21.2.2.6.7. Logging Options
            8. 21.2.2.6.8. Network Options
            9. 21.2.2.6.9. Security Options
        3. 21.2.3. Additional Resources
          1. 21.2.3.1. Installed Documentation
          2. 21.2.3.2. Online Documentation
      3. 21.3. Printer Configuration
        1. 21.3.1. Starting the Printer Configuration Tool
        2. 21.3.2. Starting Printer Setup
        3. 21.3.3. Adding a Local Printer
        4. 21.3.4. Adding an AppSocket/HP JetDirect printer
        5. 21.3.5. Adding an IPP Printer
        6. 21.3.6. Adding an LPD/LPR Host or Printer
        7. 21.3.7. Adding a Samba (SMB) printer
        8. 21.3.8. Selecting the Printer Model and Finishing
        9. 21.3.9. Printing a Test Page
        10. 21.3.10. Modifying Existing Printers
          1. 21.3.10.1. The Settings Page
          2. 21.3.10.2. The Policies Page
            1. 21.3.10.2.1. Sharing Printers
            2. 21.3.10.2.2. The Access Control Page
            3. 21.3.10.2.3. The Printer Options Page
            4. 21.3.10.2.4. Job Options Page
            5. 21.3.10.2.5. Ink/Toner Levels Page
          3. 21.3.10.3. Managing Print Jobs
        11. 21.3.11. Additional Resources
          1. 21.3.11.1. Installed Documentation
          2. 21.3.11.2. Useful Websites
    7. 22. Configuring NTP Using ntpd
      1. 22.1. Introduction to NTP
      2. 22.2. NTP Strata
      3. 22.3. Understanding NTP
      4. 22.4. Understanding the Drift File
      5. 22.5. UTC, Timezones, and DST
      6. 22.6. Authentication Options for NTP
      7. 22.7. Managing the Time on Virtual Machines
      8. 22.8. Understanding Leap Seconds
      9. 22.9. Understanding the ntpd Configuration File
      10. 22.10. Understanding the ntpd Sysconfig File
      11. 22.11. Checking if the NTP Daemon is Installed
      12. 22.12. Installing the NTP Daemon (ntpd)
      13. 22.13. Checking the Status of NTP
      14. 22.14. Configure the Firewall to Allow Incoming NTP Packets
        1. 22.14.1. Configure the Firewall Using the Graphical Tool
        2. 22.14.2. Configure the Firewall Using the Command Line
          1. 22.14.2.1. Checking Network Access for Incoming NTP Using the Command Line
      15. 22.15. Configure ntpdate Servers
      16. 22.16. Configure NTP
        1. 22.16.1. Configure Access Control to an NTP Service
        2. 22.16.2. Configure Rate Limiting Access to an NTP Service
        3. 22.16.3. Adding a Peer Address
        4. 22.16.4. Adding a Server Address
        5. 22.16.5. Adding a Broadcast or Multicast Server Address
        6. 22.16.6. Adding a Manycast Client Address
        7. 22.16.7. Adding a Broadcast Client Address
        8. 22.16.8. Adding a Manycast Server Address
        9. 22.16.9. Adding a Multicast Client Address
        10. 22.16.10. Configuring the Burst Option
        11. 22.16.11. Configuring the iburst Option
        12. 22.16.12. Configuring Symmetric Authentication Using a Key
        13. 22.16.13. Configuring the Poll Interval
        14. 22.16.14. Configuring Server Preference
        15. 22.16.15. Configuring the Time-to-Live for NTP Packets
        16. 22.16.16. Configuring the NTP Version to Use
      17. 22.17. Configuring the Hardware Clock Update
      18. 22.18. Configuring Clock Sources
      19. 22.19. Additional Resources
        1. 22.19.1. Installed Documentation
        2. 22.19.2. Useful Websites
    8. 23. Configuring PTP Using ptp4l
      1. 23.1. Introduction to PTP
        1. 23.1.1. Understanding PTP
        2. 23.1.2. Advantages of PTP
      2. 23.2. Using PTP
        1. 23.2.1. Checking for Driver and Hardware Support
        2. 23.2.2. Installing PTP
        3. 23.2.3. Starting ptp4l
          1. 23.2.3.1. Selecting a Delay Measurement Mechanism
      3. 23.3. Specifying a Configuration File
      4. 23.4. Using the PTP Management Client
      5. 23.5. Synchronizing the Clocks
      6. 23.6. Verifying Time Synchronization
      7. 23.7. Serving PTP Time With NTP
      8. 23.8. Serving NTP Time With PTP
      9. 23.9. Synchronize to PTP or NTP Time Using timemaster
        1. 23.9.1. Starting timemaster as a Service
        2. 23.9.2. Understanding the timemaster Configuration File
        3. 23.9.3. Configuring timemaster Options
      10. 23.10. Improving Accuracy
      11. 23.11. Additional Resources
        1. 23.11.1. Installed Documentation
        2. 23.11.2. Useful Websites
  8. VII. Monitoring and Automation
    1. 24. System Monitoring Tools
      1. 24.1. Viewing System Processes
        1. 24.1.1. Using the ps Command
        2. 24.1.2. Using the top Command
        3. 24.1.3. Using the System Monitor Tool
      2. 24.2. Viewing Memory Usage
        1. 24.2.1. Using the free Command
        2. 24.2.2. Using the System Monitor Tool
      3. 24.3. Viewing CPU Usage
        1. 24.3.1. Using the System Monitor Tool
      4. 24.4. Viewing Block Devices and File Systems
        1. 24.4.1. Using the lsblk Command
        2. 24.4.2. Using the blkid Command
        3. 24.4.3. Using the findmnt Command
        4. 24.4.4. Using the df Command
        5. 24.4.5. Using the du Command
        6. 24.4.6. Using the System Monitor Tool
        7. 24.4.7. Monitoring Files and Directories with gamin
      5. 24.5. Viewing Hardware Information
        1. 24.5.1. Using the lspci Command
        2. 24.5.2. Using the lsusb Command
        3. 24.5.3. Using the lspcmcia Command
        4. 24.5.4. Using the lscpu Command
      6. 24.6. Monitoring Performance with Net-SNMP
        1. 24.6.1. Installing Net-SNMP
        2. 24.6.2. Running the Net-SNMP Daemon
          1. 24.6.2.1. Starting the Service
          2. 24.6.2.2. Stopping the Service
          3. 24.6.2.3. Restarting the Service
        3. 24.6.3. Configuring Net-SNMP
          1. 24.6.3.1. Setting System Information
          2. 24.6.3.2. Configuring Authentication
        4. 24.6.4. Retrieving Performance Data over SNMP
          1. 24.6.4.1. Hardware Configuration
          2. 24.6.4.2. CPU and Memory Information
          3. 24.6.4.3. File System and Disk Information
          4. 24.6.4.4. Network Information
        5. 24.6.5. Extending Net-SNMP
          1. 24.6.5.1. Extending Net-SNMP with Shell Scripts
          2. 24.6.5.2. Extending Net-SNMP with Perl
      7. 24.7. Additional Resources
        1. 24.7.1. Installed Documentation
    2. 25. Viewing and Managing Log Files
      1. 25.1. Installing rsyslog
        1. 25.1.1. Upgrading to rsyslog version 7
      2. 25.2. Locating Log Files
      3. 25.3. Basic Configuration of Rsyslog
        1. 25.3.1. Filters
        2. 25.3.2. Actions
        3. 25.3.3. Templates
        4. 25.3.4. Global Directives
        5. 25.3.5. Log Rotation
      4. 25.4. Using the New Configuration Format
        1. 25.4.1. Rulesets
        2. 25.4.2. Compatibility with sysklogd
      5. 25.5. Working with Queues in Rsyslog
        1. 25.5.1. Defining Queues
        2. 25.5.2. Creating a New Directory for rsyslog Log Files
        3. 25.5.3. Managing Queues
        4. 25.5.4. Using the New Syntax for rsyslog queues
      6. 25.6. Configuring rsyslog on a Logging Server
        1. 25.6.1. Using The New Template Syntax on a Logging Server
      7. 25.7. Using Rsyslog Modules
        1. 25.7.1. Importing Text Files
        2. 25.7.2. Exporting Messages to a Database
        3. 25.7.3. Enabling Encrypted Transport
        4. 25.7.4. Using RELP
      8. 25.8. Debugging Rsyslog
      9. 25.9. Managing Log Files in a Graphical Environment
        1. 25.9.1. Viewing Log Files
        2. 25.9.2. Adding a Log File
        3. 25.9.3. Monitoring Log Files
      10. 25.10. Additional Resources
    3. 26. Upgrading MySQL
    4. 27. Automating System Tasks
      1. 27.1. Cron and Anacron
        1. 27.1.1. Installing Cron and Anacron
        2. 27.1.2. Running the Crond Service
          1. 27.1.2.1. Starting and Stopping the Cron Service
          2. 27.1.2.2. Stopping the Cron Service
          3. 27.1.2.3. Restarting the Cron Service
        3. 27.1.3. Configuring Anacron Jobs
          1. 27.1.3.1. Examples of Anacron Jobs
        4. 27.1.4. Configuring Cron Jobs
        5. 27.1.5. Controlling Access to Cron
        6. 27.1.6. Black and White Listing of Cron Jobs
      2. 27.2. At and Batch
        1. 27.2.1. Installing At and Batch
        2. 27.2.2. Running the At Service
          1. 27.2.2.1. Starting and Stopping the At Service
          2. 27.2.2.2. Stopping the At Service
          3. 27.2.2.3. Restarting the At Service
        3. 27.2.3. Configuring an At Job
        4. 27.2.4. Configuring a Batch Job
        5. 27.2.5. Viewing Pending Jobs
        6. 27.2.6. Additional Command-Line Options
        7. 27.2.7. Controlling Access to At and Batch
      3. 27.3. Additional Resources
    5. 28. Automatic Bug Reporting Tool (ABRT)
      1. 28.1. Installing ABRT and Starting its Services
      2. 28.2. Using the Graphical User Interface
      3. 28.3. Using the Command-Line Interface
        1. 28.3.1. Viewing Problems
        2. 28.3.2. Reporting Problems
        3. 28.3.3. Deleting Problems
      4. 28.4. Configuring ABRT
        1. 28.4.1. ABRT Events
        2. 28.4.2. Standard ABRT Installation Supported Events
        3. 28.4.3. Event Configuration in ABRT GUI
        4. 28.4.4. ABRT Specific Configuration
        5. 28.4.5. Configuring ABRT to Detect a Kernel Panic
        6. 28.4.6. Automatic Downloads and Installation of Debuginfo Packages
        7. 28.4.7. Configuring Automatic Reporting for Specific Types of Crashes
        8. 28.4.8. Uploading and Reporting Using a Proxy Server
        9. 28.4.9. Configuring Automatic Reporting
      5. 28.5. Configuring Centralized Crash Collection
        1. 28.5.1. Configuration Steps Required on a Dedicated System
        2. 28.5.2. Configuration Steps Required on a Client System
        3. 28.5.3. Saving Package Information
        4. 28.5.4. Testing ABRT's Crash Detection
    6. 29. OProfile
      1. 29.1. Overview of Tools
      2. 29.2. Configuring OProfile
        1. 29.2.1. Specifying the Kernel
        2. 29.2.2. Setting Events to Monitor
          1. 29.2.2.1. Sampling Rate
          2. 29.2.2.2. Unit Masks
        3. 29.2.3. Separating Kernel and User-space Profiles
      3. 29.3. Starting and Stopping OProfile
      4. 29.4. Saving Data
      5. 29.5. Analyzing the Data
        1. 29.5.1. Using opreport
        2. 29.5.2. Using opreport on a Single Executable
        3. 29.5.3. Getting more detailed output on the modules
        4. 29.5.4. Using opannotate
      6. 29.6. Understanding /dev/oprofile/
      7. 29.7. Example Usage
      8. 29.8. OProfile Support for Java
        1. 29.8.1. Profiling Java Code
      9. 29.9. Graphical Interface
      10. 29.10. OProfile and SystemTap
      11. 29.11. Additional Resources
        1. 29.11.1. Installed Docs
        2. 29.11.2. Useful Websites
  9. VIII. Kernel, Module and Driver Configuration
    1. 30. Manually Upgrading the Kernel
      1. 30.1. Overview of Kernel Packages
      2. 30.2. Preparing to Upgrade
      3. 30.3. Downloading the Upgraded Kernel
      4. 30.4. Performing the Upgrade
      5. 30.5. Verifying the Initial RAM Disk Image
      6. 30.6. Verifying the Boot Loader
        1. 30.6.1. Configuring the GRUB Boot Loader
        2. 30.6.2. Configuring the Loopback Device Limit
        3. 30.6.3. Configuring the OS/400 Boot Loader
        4. 30.6.4. Configuring the YABOOT Boot Loader
    2. 31. Working with Kernel Modules
      1. 31.1. Listing Currently-Loaded Modules
      2. 31.2. Displaying Information About a Module
      3. 31.3. Loading a Module
      4. 31.4. Unloading a Module
      5. 31.5. Blacklisting a Module
      6. 31.6. Setting Module Parameters
        1. 31.6.1. Loading a Customized Module - Temporary Changes
        2. 31.6.2. Loading a Customized Module - Persistent Changes
      7. 31.7. Persistent Module Loading
      8. 31.8. Specific Kernel Module Capabilities
        1. 31.8.1. Using Channel Bonding
          1. 31.8.1.1. Bonding Module Directives
      9. 31.9. Additional Resources
    3. 32. The kdump Crash Recovery Service
      1. 32.1. Installing the kdump Service
      2. 32.2. Configuring the kdump Service
        1. 32.2.1. Configuring kdump at First Boot
        2. 32.2.2. Using the Kernel Dump Configuration Utility
        3. 32.2.3. Configuring kdump on the Command Line
        4. 32.2.4. Testing the Configuration
      3. 32.3. Analyzing the Core Dump
        1. 32.3.1. Running the crash Utility
        2. 32.3.2. Displaying the Message Buffer
        3. 32.3.3. Displaying a Backtrace
        4. 32.3.4. Displaying a Process Status
        5. 32.3.5. Displaying Virtual Memory Information
        6. 32.3.6. Displaying Open Files
        7. 32.3.7. Exiting the Utility
      4. 32.4. Using fadump on IBM PowerPC hardware
      5. 32.5. Using sadump on Fujitsu PRIMEQUEST systems
        1. 32.5.1. Configure Red Hat Enterprise Linux for sadump
        2. 32.5.2. Check the memory dump
      6. 32.6. Additional Resources
  10. IX. System Recovery
    1. 33. System Recovery
      1. 33.1. Rescue Mode
      2. 33.2. Single-User Mode
      3. 33.3. Emergency Mode
      4. 33.4. Resolving Problems in System Recovery Modes
    2. 34. Relax-and-Recover (ReaR)
      1. 34.1. Basic ReaR Usage
        1. 34.1.1. Installing ReaR
        2. 34.1.2. Configuring ReaR
        3. 34.1.3. Creating a Rescue System
        4. 34.1.4. Scheduling ReaR
        5. 34.1.5. Performing a System Rescue
      2. 34.2. Integrating ReaR with Backup Software
        1. 34.2.1. The Built-in Backup Method
          1. 34.2.1.1. Configuring the Internal Backup Method
          2. 34.2.1.2. Creating a Backup Using the Internal Backup Method
        2. 34.2.2. Supported Backup Methods
        3. 34.2.3. Unsupported Backup Methods
  11. A. Consistent Network Device Naming
    1. A.1. Affected Systems
    2. A.2. System Requirements
    3. A.3. Enabling and Disabling the Feature
    4. A.4. Notes for Administrators
  12. B. RPM
    1. B.1. RPM Design Goals
    2. B.2. Using RPM
      1. B.2.1. Finding RPM Packages
      2. B.2.2. Installing and Upgrading
        1. B.2.2.1. Package Already Installed
        2. B.2.2.2. Conflicting Files
        3. B.2.2.3. Unresolved Dependency
      3. B.2.3. Configuration File Changes
      4. B.2.4. Uninstalling
      5. B.2.5. Freshening
      6. B.2.6. Querying
      7. B.2.7. Verifying
    3. B.3. Checking a Package's Signature
      1. B.3.1. Importing Keys
      2. B.3.2. Verifying Signature of Packages
    4. B.4. Practical and Common Examples of RPM Usage
    5. B.5. Additional Resources
      1. B.5.1. Installed Documentation
      2. B.5.2. Useful Websites
  13. C. The X Window System
    1. C.1. The X Server
    2. C.2. Desktop Environments and Window Managers
      1. C.2.1. Maximum number of concurrent GUI sessions
      2. C.2.2. Desktop Environments
      3. C.2.3. Window Managers
    3. C.3. X Server Configuration Files
      1. C.3.1. The Structure of the Configuration
      2. C.3.2. The xorg.conf.d Directory
      3. C.3.3. The xorg.conf File
        1. C.3.3.1. The InputClass section
        2. C.3.3.2. The InputDevice section
        3. C.3.3.3. The ServerFlags section
        4. C.3.3.4. The ServerLayout Section
        5. C.3.3.5. The Files section
        6. C.3.3.6. The Monitor section
        7. C.3.3.7. The Device section
        8. C.3.3.8. The Screen section
        9. C.3.3.9. The DRI section
    4. C.4. Fonts
      1. C.4.1. Adding Fonts to Fontconfig
    5. C.5. Runlevels and X
      1. C.5.1. Runlevel 3
      2. C.5.2. Runlevel 5
    6. C.6. Accessing Graphical Applications Remotely
    7. C.7. Additional Resources
      1. C.7.1. Installed Documentation
      2. C.7.2. Useful Websites
  14. D. The sysconfig Directory
    1. D.1. Files in the /etc/sysconfig/ Directory
      1. D.1.1. /etc/sysconfig/arpwatch
      2. D.1.2. /etc/sysconfig/authconfig
      3. D.1.3. /etc/sysconfig/autofs
      4. D.1.4. /etc/sysconfig/clock
      5. D.1.5. /etc/sysconfig/dhcpd
      6. D.1.6. /etc/sysconfig/firstboot
      7. D.1.7. /etc/sysconfig/i18n
      8. D.1.8. /etc/sysconfig/init
      9. D.1.9. /etc/sysconfig/ip6tables-config
      10. D.1.10. /etc/sysconfig/kernel
        1. D.1.10.1. Keeping an old kernel version as the default
        2. D.1.10.2. Setting a kernel debugger as the default kernel
      11. D.1.11. /etc/sysconfig/keyboard
      12. D.1.12. /etc/sysconfig/ldap
      13. D.1.13. /etc/sysconfig/named
      14. D.1.14. /etc/sysconfig/network
      15. D.1.15. /etc/sysconfig/ntpd
      16. D.1.16. /etc/sysconfig/quagga
      17. D.1.17. /etc/sysconfig/radvd
      18. D.1.18. /etc/sysconfig/samba
      19. D.1.19. /etc/sysconfig/saslauthd
      20. D.1.20. /etc/sysconfig/selinux
      21. D.1.21. /etc/sysconfig/sendmail
      22. D.1.22. /etc/sysconfig/spamassassin
      23. D.1.23. /etc/sysconfig/squid
      24. D.1.24. /etc/sysconfig/system-config-users
      25. D.1.25. /etc/sysconfig/vncservers
      26. D.1.26. /etc/sysconfig/xinetd
    2. D.2. Directories in the /etc/sysconfig/ Directory
    3. D.3. Additional Resources
      1. D.3.1. Installed Documentation
  15. E. The proc File System
    1. E.1. A Virtual File System
      1. E.1.1. Viewing Virtual Files
      2. E.1.2. Changing Virtual Files
    2. E.2. Top-level Files within the proc File System
      1. E.2.1. /proc/buddyinfo
      2. E.2.2. /proc/cmdline
      3. E.2.3. /proc/cpuinfo
      4. E.2.4. /proc/crypto
      5. E.2.5. /proc/devices
      6. E.2.6. /proc/dma
      7. E.2.7. /proc/execdomains
      8. E.2.8. /proc/fb
      9. E.2.9. /proc/filesystems
      10. E.2.10. /proc/interrupts
      11. E.2.11. /proc/iomem
      12. E.2.12. /proc/ioports
      13. E.2.13. /proc/kcore
      14. E.2.14. /proc/kmsg
      15. E.2.15. /proc/loadavg
      16. E.2.16. /proc/locks
      17. E.2.17. /proc/mdstat
      18. E.2.18. /proc/meminfo
      19. E.2.19. /proc/misc
      20. E.2.20. /proc/modules
      21. E.2.21. /proc/mounts
      22. E.2.22. /proc/mtrr
      23. E.2.23. /proc/partitions
      24. E.2.24. /proc/slabinfo
      25. E.2.25. /proc/stat
      26. E.2.26. /proc/swaps
      27. E.2.27. /proc/sysrq-trigger
      28. E.2.28. /proc/uptime
      29. E.2.29. /proc/version
    3. E.3. Directories within /proc/
      1. E.3.1. Process Directories
        1. E.3.1.1. /proc/self/
      2. E.3.2. /proc/bus/
      3. E.3.3. /proc/bus/pci
      4. E.3.4. /proc/driver/
      5. E.3.5. /proc/fs
      6. E.3.6. /proc/irq/
      7. E.3.7. /proc/net/
      8. E.3.8. /proc/scsi/
      9. E.3.9. /proc/sys/
        1. E.3.9.1. /proc/sys/dev/
        2. E.3.9.2. /proc/sys/fs/
        3. E.3.9.3. /proc/sys/kernel/
        4. E.3.9.4. /proc/sys/net/
        5. E.3.9.5. /proc/sys/vm/
      10. E.3.10. /proc/sysvipc/
      11. E.3.11. /proc/tty/
      12. E.3.12. /proc/PID/
    4. E.4. Using the sysctl Command
    5. E.5. Additional Resources
  16. F. Revision History
  17. Index
  18. Legal Notice

22.19.2. Useful Websites

Content from doc.ntp.org is not included.http://doc.ntp.org/
The NTP Documentation Archive
Content from www.eecis.udel.edu is not included.http://www.eecis.udel.edu/~mills/ntp.html
Network Time Synchronization Research Project.
Content from www.eecis.udel.edu is not included.http://www.eecis.udel.edu/~mills/ntp/html/manyopt.html
Information on Automatic Server Discovery in NTPv4.
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