Red Hat Enterprise Linux 6

Deployment Guide

Deployment, Configuration and Administration of Red Hat Enterprise Linux 6

Marie Doleželová

Red Hat Customer Content Services

Mirek Jahoda

Red Hat Customer Content Services

Maxim Svistunov

Red Hat Customer Content Services

Stephen Wadeley

Red Hat Customer Content Services

Tomáš Čapek

Red Hat Customer Content Services

Robert Krátký

Red Hat Customer Content Services

Jana Heves

Red Hat Customer Content Services

Jaromír Hradílek

Red Hat Customer Content Services

Douglas Silas

Red Hat Customer Content Services

Barbora Ančincová

Red Hat Customer Content Services

Petr Kovář

Red Hat Customer Content Services

Jiří Herrmann

Red Hat Customer Content Services

Peter Ondrejka

Red Hat Customer Content Services

Petr Bokoč

Red Hat Customer Content Services

Martin Prpič

Red Hat Product Security

Eva Majoršinová

Red Hat Customer Content Services

Eva Kopalová

Red Hat Customer Content Services

Miroslav Svoboda

Red Hat Customer Content Services

Milan Navrátil

Red Hat Customer Content Services

Ella Deon Lackey

Red Hat Customer Content Services

Florian Nadge

Red Hat Customer Content Services

John Ha

Red Hat Customer Content Services

David O'Brien

Red Hat Customer Content Services

Michael Hideo

Red Hat Customer Content Services

Don Domingo

Red Hat Customer Content Services

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Abstract

The Deployment Guide documents relevant information regarding the deployment, configuration and administration of Red Hat Enterprise Linux 6. It is oriented towards system administrators with a basic understanding of the system.
I. Basic System Configuration
1. Keyboard Configuration
1.1. Changing the Keyboard Layout
1.2. Adding the Keyboard Layout Indicator
1.3. Setting Up a Typing Break
2. Date and Time Configuration
2.1. Date/Time Properties Tool
2.1.1. Date and Time Properties
2.1.2. Network Time Protocol Properties
2.1.3. Time Zone Properties
2.2. Command Line Configuration
2.2.1. Date and Time Setup
2.2.2. Network Time Protocol Setup
3. Managing Users and Groups
3.1. What Users and Groups Are
3.2. Managing Users via the User Manager Application
3.2.1. Viewing Users
3.2.2. Adding a New User
3.2.3. Modifying User Properties
3.3. Managing Groups via the User Manager Application
3.3.1. Viewing Groups
3.3.2. Adding a New Group
3.3.3. Modifying Group Properties
3.4. Managing Users via Command-Line Tools
3.4.1. Creating Users
3.4.2. Attaching New Users to Groups
3.4.3. Updating Users' Authentication
3.4.4. Modifying User Settings
3.4.5. Deleting Users
3.4.6. Displaying Comprehensive User Information
3.5. Managing Groups via Command-Line Tools
3.5.1. Creating Groups
3.5.2. Attaching Users to Groups
3.5.3. Updating Group Authentication
3.5.4. Modifying Group Settings
3.5.5. Deleting Groups
3.6. Additional Resources
3.6.1. Installed Documentation
4. Gaining Privileges
4.1. The su Command
4.2. The sudo Command
4.3. Additional Resources
5. Console Access
5.1. Disabling Console Program Access for Non-root Users
5.2. Disabling Rebooting Using Ctrl+Alt+Del
II. Subscription and Support
6. Registering the System and Managing Subscriptions
6.1. Registering the System and Attaching Subscriptions
6.2. Managing Software Repositories
6.3. Removing Subscriptions
6.4. Additional Resources
7. Accessing Support Using the Red Hat Support Tool
7.1. Installing the Red Hat Support Tool
7.2. Registering the Red Hat Support Tool Using the Command Line
7.3. Using the Red Hat Support Tool in Interactive Shell Mode
7.4. Configuring the Red Hat Support Tool
7.4.1. Saving Settings to the Configuration Files
7.5. Opening and Updating Support Cases Using Interactive Mode
7.6. Viewing Support Cases on the Command Line
7.7. Additional Resources
III. Installing and Managing Software
8. Yum
8.1. Checking For and Updating Packages
8.1.1. Checking For Updates
8.1.2. Updating Packages
8.1.3. Preserving Configuration File Changes
8.1.4. Upgrading the System Off-line with ISO and Yum
8.2. Packages and Package Groups
8.2.1. Searching Packages
8.2.2. Listing Packages
8.2.3. Displaying Package Information
8.2.4. Installing Packages
8.2.5. Removing Packages
8.3. Working with Transaction History
8.3.1. Listing Transactions
8.3.2. Examining Transactions
8.3.3. Reverting and Repeating Transactions
8.3.4. Completing Transactions
8.3.5. Starting New Transaction History
8.4. Configuring Yum and Yum Repositories
8.4.1. Setting [main] Options
8.4.2. Setting [repository] Options
8.4.3. Using Yum Variables
8.4.4. Viewing the Current Configuration
8.4.5. Adding, Enabling, and Disabling a Yum Repository
8.4.6. Creating a Yum Repository
8.4.7. Working with Yum Cache
8.4.8. Adding the Optional and Supplementary Repositories
8.5. Yum Plug-ins
8.5.1. Enabling, Configuring, and Disabling Yum Plug-ins
8.5.2. Installing Additional Yum Plug-ins
8.5.3. Plug-in Descriptions
8.6. Additional Resources
9. PackageKit
9.1. Updating Packages with Software Update
9.2. Using Add/Remove Software
9.2.1. Refreshing Software Sources (Yum Repositories)
9.2.2. Finding Packages with Filters
9.2.3. Installing and Removing Packages (and Dependencies)
9.2.4. Installing and Removing Package Groups
9.2.5. Viewing the Transaction Log
9.3. PackageKit Architecture
9.4. Additional Resources
IV. Networking
10. NetworkManager
10.1. The NetworkManager Daemon
10.2. Interacting with NetworkManager
10.2.1. Connecting to a Network
10.2.2. Configuring New and Editing Existing Connections
10.2.3. Connecting to a Network Automatically
10.2.4. User and System Connections
10.3. Establishing Connections
10.3.1. Establishing a Wired (Ethernet) Connection
10.3.2. Establishing a Wireless Connection
10.3.3. Establishing a Mobile Broadband Connection
10.3.4. Establishing a VPN Connection
10.3.5. Establishing a DSL Connection
10.3.6. Establishing a Bond Connection
10.3.7. Establishing a VLAN Connection
10.3.8. Establishing an IP-over-InfiniBand (IPoIB) Connection
10.3.9. Configuring Connection Settings
11. Network Interfaces
11.1. Network Configuration Files
11.1.1. Setting the Host Name
11.2. Interface Configuration Files
11.2.1. Ethernet Interfaces
11.2.2. Specific ifcfg Options for Linux on System z
11.2.3. Required ifcfg Options for Linux on System z
11.2.4. Channel Bonding Interfaces
11.2.5. Configuring a VLAN over a Bond
11.2.6. Network Bridge
11.2.7. Setting Up 802.1Q VLAN Tagging
11.2.8. Alias and Clone Files
11.2.9. Dialup Interfaces
11.2.10. Other Interfaces
11.3. Interface Control Scripts
11.4. Static Routes and the Default Gateway
11.5. Configuring Static Routes in ifcfg files
11.5.1. Static Routes Using the IP Command Arguments Format
11.5.2. Network/Netmask Directives Format
11.6. Configuring IPv6 Tokenized Interface Identifiers
11.7. Network Function Files
11.8. Ethtool
11.9. Configuring netconsole
11.10. Additional Resources
V. Infrastructure Services
12. Services and Daemons
12.1. Configuring the Default Runlevel
12.2. Configuring the Services
12.2.1. Using the Service Configuration Utility
12.2.2. Using the ntsysv Utility
12.2.3. Using the chkconfig Utility
12.3. Running Services
12.3.1. Determining the Service Status
12.3.2. Starting a Service
12.3.3. Stopping a Service
12.3.4. Restarting a Service
12.4. Additional Resources
12.4.1. Installed Documentation
12.4.2. Related Books
13. Configuring Authentication
13.1. Configuring System Authentication
13.1.1. Launching the Authentication Configuration Tool UI
13.1.2. Selecting the Identity Store for Authentication
13.1.3. Configuring Alternative Authentication Features
13.1.4. Configuring Authentication from the Command Line
13.1.5. Using Custom Home Directories
13.2. Using and Caching Credentials with SSSD
13.2.1. About SSSD
13.2.2. Setting up the sssd.conf File
13.2.3. Starting and Stopping SSSD
13.2.4. SSSD and System Services
13.2.5. Configuring Services: NSS
13.2.6. Configuring Services: PAM
13.2.7. Configuring Services: autofs
13.2.8. Configuring Services: sudo
13.2.9. Configuring Services: OpenSSH and Cached Keys
13.2.10. SSSD and Identity Providers (Domains)
13.2.11. Creating Domains: LDAP
13.2.12. Creating Domains: Identity Management (IdM)
13.2.13. Creating Domains: Active Directory
13.2.14. Configuring Domains: Active Directory as an LDAP Provider (Alternative)
13.2.15. Domain Options: Setting Username Formats
13.2.16. Domain Options: Enabling Offline Authentication
13.2.17. Domain Options: Setting Password Expirations
13.2.18. Domain Options: Using DNS Service Discovery
13.2.19. Domain Options: Using IP Addresses in Certificate Subject Names (LDAP Only)
13.2.20. Creating Domains: Proxy
13.2.21. Creating Domains: Kerberos Authentication
13.2.22. Creating Domains: Access Control
13.2.23. Creating Domains: Primary Server and Backup Servers
13.2.24. Installing SSSD Utilities
13.2.25. SSSD and UID and GID Numbers
13.2.26. Creating Local System Users
13.2.27. Seeding Users into the SSSD Cache During Kickstart
13.2.28. Managing the SSSD Cache
13.2.29. Downgrading SSSD
13.2.30. Using NSCD with SSSD
13.2.31. Troubleshooting SSSD
14. OpenSSH
14.1. The SSH Protocol
14.1.1. Why Use SSH?
14.1.2. Main Features
14.1.3. Protocol Versions
14.1.4. Event Sequence of an SSH Connection
14.2. Configuring OpenSSH
14.2.1. Configuration Files
14.2.2. Starting an OpenSSH Server
14.2.3. Requiring SSH for Remote Connections
14.2.4. Using Key-Based Authentication
14.3. Using OpenSSH Certificate Authentication
14.3.1. Introduction to SSH Certificates
14.3.2. Support for SSH Certificates
14.3.3. Creating SSH CA Certificate Signing Keys
14.3.4. Distributing and Trusting SSH CA Public Keys
14.3.5. Creating SSH Certificates
14.3.6. Signing an SSH Certificate Using a PKCS#11 Token
14.3.7. Viewing an SSH CA Certificate
14.3.8. Revoking an SSH CA Certificate
14.4. OpenSSH Clients
14.4.1. Using the ssh Utility
14.4.2. Using the scp Utility
14.4.3. Using the sftp Utility
14.5. More Than a Secure Shell
14.5.1. X11 Forwarding
14.5.2. Port Forwarding
14.6. Additional Resources
14.6.1. Installed Documentation
14.6.2. Useful Websites
15. TigerVNC
15.1. VNC Server
15.1.1. Installing VNC Server
15.1.2. Configuring VNC Server
15.1.3. Starting VNC Server
15.1.4. Terminating a VNC Session
15.2. Sharing an Existing Desktop
15.3. Using a VNC Viewer
15.3.1. Installing the VNC Viewer
15.3.2. Connecting to a VNC Server
15.3.3. Connecting to VNC Server Using SSH
15.4. Additional Resources
VI. Servers
16. DHCP Servers
16.1. Why Use DHCP?
16.2. Configuring a DHCPv4 Server
16.2.1. Configuration File
16.2.2. Lease Database
16.2.3. Starting and Stopping the Server
16.2.4. DHCP Relay Agent
16.3. Configuring a DHCPv4 Client
16.4. Configuring a Multihomed DHCP Server
16.4.1. Host Configuration
16.5. DHCP for IPv6 (DHCPv6)
16.5.1. Configuring a DHCPv6 Server
16.5.2. Configuring a DHCPv6 Client
16.6. Additional Resources
16.6.1. Installed Documentation
17. DNS Servers
17.1. Introduction to DNS
17.1.1. Nameserver Zones
17.1.2. Nameserver Types
17.1.3. BIND as a Nameserver
17.2. BIND
17.2.1. Configuring the named Service
17.2.2. Editing Zone Files
17.2.3. Using the rndc Utility
17.2.4. Using the dig Utility
17.2.5. Advanced Features of BIND
17.2.6. Common Mistakes to Avoid
17.2.7. Additional Resources
18. Web Servers
18.1. The Apache HTTP Server
18.1.1. New Features
18.1.2. Notable Changes
18.1.3. Updating the Configuration
18.1.4. Running the httpd Service
18.1.5. Editing the Configuration Files
18.1.6. Working with Modules
18.1.7. Setting Up Virtual Hosts
18.1.8. Setting Up an SSL Server
18.1.9. Enabling the mod_ssl Module
18.1.10. Enabling the mod_nss Module
18.1.11. Using an Existing Key and Certificate
18.1.12. Generating a New Key and Certificate
18.1.13. Configure the Firewall for HTTP and HTTPS Using the Command Line
18.1.14. Additional Resources
19. Mail Servers
19.1. Email Protocols
19.1.1. Mail Transport Protocols
19.1.2. Mail Access Protocols
19.2. Email Program Classifications
19.2.1. Mail Transport Agent
19.2.2. Mail Delivery Agent
19.2.3. Mail User Agent
19.3. Mail Transport Agents
19.3.1. Postfix
19.3.2. Sendmail
19.3.3. Fetchmail
19.3.4. Mail Transport Agent (MTA) Configuration
19.4. Mail Delivery Agents
19.4.1. Procmail Configuration
19.4.2. Procmail Recipes
19.5. Mail User Agents
19.5.1. Securing Communication
19.6. Additional Resources
19.6.1. Installed Documentation
19.6.2. Online Documentation
19.6.3. Related Books
20. Directory Servers
20.1. OpenLDAP
20.1.1. Introduction to LDAP
20.1.2. Installing the OpenLDAP Suite
20.1.3. Configuring an OpenLDAP Server
20.1.4. Running an OpenLDAP Server
20.1.5. Configuring a System to Authenticate Using OpenLDAP
20.1.6. Additional Resources
21. File and Print Servers
21.1. Samba
21.1.1. Introduction to Samba
21.1.2. Samba Daemons and Related Services
21.1.3. Connecting to a Samba Share
21.1.4. Configuring a Samba Server
21.1.5. Starting and Stopping Samba
21.1.6. Samba Server Types and the smb.conf File
21.1.7. Samba Security Modes
21.1.8. Samba Account Information Databases
21.1.9. Samba Network Browsing
21.1.10. Samba with CUPS Printing Support
21.1.11. Samba Distribution Programs
21.1.12. Additional Resources
21.2. FTP
21.2.1. The File Transfer Protocol
21.2.2. The vsftpd Server
21.2.3. Additional Resources
21.3. Printer Configuration
21.3.1. Starting the Printer Configuration Tool
21.3.2. Starting Printer Setup
21.3.3. Adding a Local Printer
21.3.4. Adding an AppSocket/HP JetDirect printer
21.3.5. Adding an IPP Printer
21.3.6. Adding an LPD/LPR Host or Printer
21.3.7. Adding a Samba (SMB) printer
21.3.8. Selecting the Printer Model and Finishing
21.3.9. Printing a Test Page
21.3.10. Modifying Existing Printers
21.3.11. Additional Resources
22. Configuring NTP Using ntpd
22.1. Introduction to NTP
22.2. NTP Strata
22.3. Understanding NTP
22.4. Understanding the Drift File
22.5. UTC, Timezones, and DST
22.6. Authentication Options for NTP
22.7. Managing the Time on Virtual Machines
22.8. Understanding Leap Seconds
22.9. Understanding the ntpd Configuration File
22.10. Understanding the ntpd Sysconfig File
22.11. Checking if the NTP Daemon is Installed
22.12. Installing the NTP Daemon (ntpd)
22.13. Checking the Status of NTP
22.14. Configure the Firewall to Allow Incoming NTP Packets
22.14.1. Configure the Firewall Using the Graphical Tool
22.14.2. Configure the Firewall Using the Command Line
22.15. Configure ntpdate Servers
22.16. Configure NTP
22.16.1. Configure Access Control to an NTP Service
22.16.2. Configure Rate Limiting Access to an NTP Service
22.16.3. Adding a Peer Address
22.16.4. Adding a Server Address
22.16.5. Adding a Broadcast or Multicast Server Address
22.16.6. Adding a Manycast Client Address
22.16.7. Adding a Broadcast Client Address
22.16.8. Adding a Manycast Server Address
22.16.9. Adding a Multicast Client Address
22.16.10. Configuring the Burst Option
22.16.11. Configuring the iburst Option
22.16.12. Configuring Symmetric Authentication Using a Key
22.16.13. Configuring the Poll Interval
22.16.14. Configuring Server Preference
22.16.15. Configuring the Time-to-Live for NTP Packets
22.16.16. Configuring the NTP Version to Use
22.17. Configuring the Hardware Clock Update
22.18. Configuring Clock Sources
22.19. Additional Resources
22.19.1. Installed Documentation
22.19.2. Useful Websites
23. Configuring PTP Using ptp4l
23.1. Introduction to PTP
23.1.1. Understanding PTP
23.1.2. Advantages of PTP
23.2. Using PTP
23.2.1. Checking for Driver and Hardware Support
23.2.2. Installing PTP
23.2.3. Starting ptp4l
23.3. Specifying a Configuration File
23.4. Using the PTP Management Client
23.5. Synchronizing the Clocks
23.6. Verifying Time Synchronization
23.7. Serving PTP Time With NTP
23.8. Serving NTP Time With PTP
23.9. Synchronize to PTP or NTP Time Using timemaster
23.9.1. Starting timemaster as a Service
23.9.2. Understanding the timemaster Configuration File
23.9.3. Configuring timemaster Options
23.10. Improving Accuracy
23.11. Additional Resources
23.11.1. Installed Documentation
23.11.2. Useful Websites
VII. Monitoring and Automation
24. System Monitoring Tools
24.1. Viewing System Processes
24.1.1. Using the ps Command
24.1.2. Using the top Command
24.1.3. Using the System Monitor Tool
24.2. Viewing Memory Usage
24.2.1. Using the free Command
24.2.2. Using the System Monitor Tool
24.3. Viewing CPU Usage
24.3.1. Using the System Monitor Tool
24.4. Viewing Block Devices and File Systems
24.4.1. Using the lsblk Command
24.4.2. Using the blkid Command
24.4.3. Using the findmnt Command
24.4.4. Using the df Command
24.4.5. Using the du Command
24.4.6. Using the System Monitor Tool
24.4.7. Monitoring Files and Directories with gamin
24.5. Viewing Hardware Information
24.5.1. Using the lspci Command
24.5.2. Using the lsusb Command
24.5.3. Using the lspcmcia Command
24.5.4. Using the lscpu Command
24.6. Monitoring Performance with Net-SNMP
24.6.1. Installing Net-SNMP
24.6.2. Running the Net-SNMP Daemon
24.6.3. Configuring Net-SNMP
24.6.4. Retrieving Performance Data over SNMP
24.6.5. Extending Net-SNMP
24.7. Additional Resources
24.7.1. Installed Documentation
25. Viewing and Managing Log Files
25.1. Installing rsyslog
25.1.1. Upgrading to rsyslog version 7
25.2. Locating Log Files
25.3. Basic Configuration of Rsyslog
25.3.1. Filters
25.3.2. Actions
25.3.3. Templates
25.3.4. Global Directives
25.3.5. Log Rotation
25.4. Using the New Configuration Format
25.4.1. Rulesets
25.4.2. Compatibility with sysklogd
25.5. Working with Queues in Rsyslog
25.5.1. Defining Queues
25.5.2. Creating a New Directory for rsyslog Log Files
25.5.3. Managing Queues
25.5.4. Using the New Syntax for rsyslog queues
25.6. Configuring rsyslog on a Logging Server
25.6.1. Using The New Template Syntax on a Logging Server
25.7. Using Rsyslog Modules
25.7.1. Importing Text Files
25.7.2. Exporting Messages to a Database
25.7.3. Enabling Encrypted Transport
25.7.4. Using RELP
25.8. Debugging Rsyslog
25.9. Managing Log Files in a Graphical Environment
25.9.1. Viewing Log Files
25.9.2. Adding a Log File
25.9.3. Monitoring Log Files
25.10. Additional Resources
26. Upgrading MySQL
27. Automating System Tasks
27.1. Cron and Anacron
27.1.1. Installing Cron and Anacron
27.1.2. Running the Crond Service
27.1.3. Configuring Anacron Jobs
27.1.4. Configuring Cron Jobs
27.1.5. Controlling Access to Cron
27.1.6. Black and White Listing of Cron Jobs
27.2. At and Batch
27.2.1. Installing At and Batch
27.2.2. Running the At Service
27.2.3. Configuring an At Job
27.2.4. Configuring a Batch Job
27.2.5. Viewing Pending Jobs
27.2.6. Additional Command-Line Options
27.2.7. Controlling Access to At and Batch
27.3. Additional Resources
28. Automatic Bug Reporting Tool (ABRT)
28.1. Installing ABRT and Starting its Services
28.2. Using the Graphical User Interface
28.3. Using the Command-Line Interface
28.3.1. Viewing Problems
28.3.2. Reporting Problems
28.3.3. Deleting Problems
28.4. Configuring ABRT
28.4.1. ABRT Events
28.4.2. Standard ABRT Installation Supported Events
28.4.3. Event Configuration in ABRT GUI
28.4.4. ABRT Specific Configuration
28.4.5. Configuring ABRT to Detect a Kernel Panic
28.4.6. Automatic Downloads and Installation of Debuginfo Packages
28.4.7. Configuring Automatic Reporting for Specific Types of Crashes
28.4.8. Uploading and Reporting Using a Proxy Server
28.4.9. Configuring Automatic Reporting
28.5. Configuring Centralized Crash Collection
28.5.1. Configuration Steps Required on a Dedicated System
28.5.2. Configuration Steps Required on a Client System
28.5.3. Saving Package Information
28.5.4. Testing ABRT's Crash Detection
29. OProfile
29.1. Overview of Tools
29.2. Configuring OProfile
29.2.1. Specifying the Kernel
29.2.2. Setting Events to Monitor
29.2.3. Separating Kernel and User-space Profiles
29.3. Starting and Stopping OProfile
29.4. Saving Data
29.5. Analyzing the Data
29.5.1. Using opreport
29.5.2. Using opreport on a Single Executable
29.5.3. Getting more detailed output on the modules
29.5.4. Using opannotate
29.6. Understanding /dev/oprofile/
29.7. Example Usage
29.8. OProfile Support for Java
29.8.1. Profiling Java Code
29.9. Graphical Interface
29.10. OProfile and SystemTap
29.11. Additional Resources
29.11.1. Installed Docs
29.11.2. Useful Websites
VIII. Kernel, Module and Driver Configuration
30. Manually Upgrading the Kernel
30.1. Overview of Kernel Packages
30.2. Preparing to Upgrade
30.3. Downloading the Upgraded Kernel
30.4. Performing the Upgrade
30.5. Verifying the Initial RAM Disk Image
30.6. Verifying the Boot Loader
30.6.1. Configuring the GRUB Boot Loader
30.6.2. Configuring the Loopback Device Limit
30.6.3. Configuring the OS/400 Boot Loader
30.6.4. Configuring the YABOOT Boot Loader
31. Working with Kernel Modules
31.1. Listing Currently-Loaded Modules
31.2. Displaying Information About a Module
31.3. Loading a Module
31.4. Unloading a Module
31.5. Blacklisting a Module
31.6. Setting Module Parameters
31.6.1. Loading a Customized Module - Temporary Changes
31.6.2. Loading a Customized Module - Persistent Changes
31.7. Persistent Module Loading
31.8. Specific Kernel Module Capabilities
31.8.1. Using Channel Bonding
31.9. Additional Resources
32. The kdump Crash Recovery Service
32.1. Installing the kdump Service
32.2. Configuring the kdump Service
32.2.1. Configuring kdump at First Boot
32.2.2. Using the Kernel Dump Configuration Utility
32.2.3. Configuring kdump on the Command Line
32.2.4. Testing the Configuration
32.3. Analyzing the Core Dump
32.3.1. Running the crash Utility
32.3.2. Displaying the Message Buffer
32.3.3. Displaying a Backtrace
32.3.4. Displaying a Process Status
32.3.5. Displaying Virtual Memory Information
32.3.6. Displaying Open Files
32.3.7. Exiting the Utility
32.4. Using fadump on IBM PowerPC hardware
32.5. Additional Resources
IX. System Recovery
33. System Recovery
33.1. Rescue Mode
33.2. Single-User Mode
33.3. Emergency Mode
33.4. Resolving Problems in System Recovery Modes
34. Relax-and-Recover (ReaR)
34.1. Basic ReaR Usage
34.1.1. Installing ReaR
34.1.2. Configuring ReaR
34.1.3. Creating a Rescue System
34.1.4. Scheduling ReaR
34.1.5. Performing a System Rescue
34.2. Integrating ReaR with Backup Software
34.2.1. The Built-in Backup Method
34.2.2. Supported Backup Methods
34.2.3. Unsupported Backup Methods
A. Consistent Network Device Naming
A.1. Affected Systems
A.2. System Requirements
A.3. Enabling and Disabling the Feature
A.4. Notes for Administrators
B. RPM
B.1. RPM Design Goals
B.2. Using RPM
B.2.1. Finding RPM Packages
B.2.2. Installing and Upgrading
B.2.3. Configuration File Changes
B.2.4. Uninstalling
B.2.5. Freshening
B.2.6. Querying
B.2.7. Verifying
B.3. Checking a Package's Signature
B.3.1. Importing Keys
B.3.2. Verifying Signature of Packages
B.4. Practical and Common Examples of RPM Usage
B.5. Additional Resources
B.5.1. Installed Documentation
B.5.2. Useful Websites
C. The X Window System
C.1. The X Server
C.2. Desktop Environments and Window Managers
C.2.1. Maximum number of concurrent GUI sessions
C.2.2. Desktop Environments
C.2.3. Window Managers
C.3. X Server Configuration Files
C.3.1. The Structure of the Configuration
C.3.2. The xorg.conf.d Directory
C.3.3. The xorg.conf File
C.4. Fonts
C.4.1. Adding Fonts to Fontconfig
C.5. Runlevels and X
C.5.1. Runlevel 3
C.5.2. Runlevel 5
C.6. Accessing Graphical Applications Remotely
C.7. Additional Resources
C.7.1. Installed Documentation
C.7.2. Useful Websites
D. The sysconfig Directory
D.1. Files in the /etc/sysconfig/ Directory
D.1.1. /etc/sysconfig/arpwatch
D.1.2. /etc/sysconfig/authconfig
D.1.3. /etc/sysconfig/autofs
D.1.4. /etc/sysconfig/clock
D.1.5. /etc/sysconfig/dhcpd
D.1.6. /etc/sysconfig/firstboot
D.1.7. /etc/sysconfig/i18n
D.1.8. /etc/sysconfig/init
D.1.9. /etc/sysconfig/ip6tables-config
D.1.10. /etc/sysconfig/keyboard
D.1.11. /etc/sysconfig/ldap
D.1.12. /etc/sysconfig/named
D.1.13. /etc/sysconfig/network
D.1.14. /etc/sysconfig/ntpd
D.1.15. /etc/sysconfig/quagga
D.1.16. /etc/sysconfig/radvd
D.1.17. /etc/sysconfig/samba
D.1.18. /etc/sysconfig/saslauthd
D.1.19. /etc/sysconfig/selinux
D.1.20. /etc/sysconfig/sendmail
D.1.21. /etc/sysconfig/spamassassin
D.1.22. /etc/sysconfig/squid
D.1.23. /etc/sysconfig/system-config-users
D.1.24. /etc/sysconfig/vncservers
D.1.25. /etc/sysconfig/xinetd
D.2. Directories in the /etc/sysconfig/ Directory
D.3. Additional Resources
D.3.1. Installed Documentation
E. The proc File System
E.1. A Virtual File System
E.1.1. Viewing Virtual Files
E.1.2. Changing Virtual Files
E.2. Top-level Files within the proc File System
E.2.1. /proc/buddyinfo
E.2.2. /proc/cmdline
E.2.3. /proc/cpuinfo
E.2.4. /proc/crypto
E.2.5. /proc/devices
E.2.6. /proc/dma
E.2.7. /proc/execdomains
E.2.8. /proc/fb
E.2.9. /proc/filesystems
E.2.10. /proc/interrupts
E.2.11. /proc/iomem
E.2.12. /proc/ioports
E.2.13. /proc/kcore
E.2.14. /proc/kmsg
E.2.15. /proc/loadavg
E.2.16. /proc/locks
E.2.17. /proc/mdstat
E.2.18. /proc/meminfo
E.2.19. /proc/misc
E.2.20. /proc/modules
E.2.21. /proc/mounts
E.2.22. /proc/mtrr
E.2.23. /proc/partitions
E.2.24. /proc/slabinfo
E.2.25. /proc/stat
E.2.26. /proc/swaps
E.2.27. /proc/sysrq-trigger
E.2.28. /proc/uptime
E.2.29. /proc/version
E.3. Directories within /proc/
E.3.1. Process Directories
E.3.2. /proc/bus/
E.3.3. /proc/bus/pci
E.3.4. /proc/driver/
E.3.5. /proc/fs
E.3.6. /proc/irq/
E.3.7. /proc/net/
E.3.8. /proc/scsi/
E.3.9. /proc/sys/
E.3.10. /proc/sysvipc/
E.3.11. /proc/tty/
E.3.12. /proc/PID/
E.4. Using the sysctl Command
E.5. Additional Resources
F. Revision History
Index