Red Hat Enterprise Linux 4

Introduction To System Administration

For Red Hat Enterprise Linux 4

Edition 2

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Abstract

This book contains basic information about Red Hat Enterprise Linux system administration, and is suitable for system administrators with limited Linux experience.
Introduction
1. Architecture-specific Information
2. Document Conventions
2.1. Typographic Conventions
2.2. Pull-quote Conventions
2.3. Notes and Warnings
3. More to Come
3.1. Send in Your Feedback
1. The Philosophy of System Administration
1.1. Automate Everything
1.2. Document Everything
1.3. Communicate as Much as Possible
1.3.1. Tell Your Users What You Are Going to Do
1.3.2. Tell Your Users What You Are Doing
1.3.3. Tell Your Users What You Have Done
1.4. Know Your Resources
1.5. Know Your Users
1.6. Know Your Business
1.7. Security Cannot be an Afterthought
1.7.1. The Risks of Social Engineering
1.8. Plan Ahead
1.9. Expect the Unexpected
1.10. Red Hat Enterprise Linux-Specific Information
1.10.1. Automation
1.10.2. Documentation and Communication
1.10.3. Security
1.11. Additional Resources
1.11.1. Installed Documentation
1.11.2. Useful Websites
1.11.3. Related Books
2. Resource Monitoring
2.1. Basic Concepts
2.2. System Performance Monitoring
2.3. Monitoring System Capacity
2.4. What to Monitor?
2.4.1. Monitoring CPU Power
2.4.2. Monitoring Bandwidth
2.4.3. Monitoring Memory
2.4.4. Monitoring Storage
2.5. Red Hat Enterprise Linux-Specific Information
2.5.1. free
2.5.2. top
2.5.3. vmstat
2.5.4. The Sysstat Suite of Resource Monitoring Tools
2.5.5. OProfile
2.6. Additional Resources
2.6.1. Installed Documentation
2.6.2. Useful Websites
2.6.3. Related Books
3. Bandwidth and Processing Power
3.1. Bandwidth
3.1.1. Buses
3.1.2. Datapaths
3.1.3. Potential Bandwidth-Related Problems
3.1.4. Potential Bandwidth-Related Solutions
3.1.5. In Summary…
3.2. Processing Power
3.2.1. Facts About Processing Power
3.2.2. Consumers of Processing Power
3.2.3. Improving a CPU Shortage
3.3. Red Hat Enterprise Linux-Specific Information
3.3.1. Monitoring Bandwidth on Red Hat Enterprise Linux
3.3.2. Monitoring CPU Utilization on Red Hat Enterprise Linux
3.4. Additional Resources
3.4.1. Installed Documentation
3.4.2. Useful Websites
3.4.3. Related Books
4. Physical and Virtual Memory
4.1. Storage Access Patterns
4.2. The Storage Spectrum
4.2.1. CPU Registers
4.2.2. Cache Memory
4.2.3. Main Memory -- RAM
4.2.4. Hard Drives
4.2.5. Off-Line Backup Storage
4.3. Basic Virtual Memory Concepts
4.3.1. Virtual Memory in Simple Terms
4.3.2. Backing Store -- the Central Tenet of Virtual Memory
4.4. Virtual Memory: The Details
4.4.1. Page Faults
4.4.2. The Working Set
4.4.3. Swapping
4.5. Virtual Memory Performance Implications
4.5.1. Worst Case Performance Scenario
4.5.2. Best Case Performance Scenario
4.6. Red Hat Enterprise Linux-Specific Information
4.7. Additional Resources
4.7.1. Installed Documentation
4.7.2. Useful Websites
4.7.3. Related Books
5. Managing Storage
5.1. An Overview of Storage Hardware
5.1.1. Disk Platters
5.1.2. Data reading/writing device
5.1.3. Access Arms
5.2. Storage Addressing Concepts
5.2.1. Geometry-Based Addressing
5.2.2. Block-Based Addressing
5.3. Mass Storage Device Interfaces
5.3.1. Historical Background
5.3.2. Present-Day Industry-Standard Interfaces
5.4. Hard Drive Performance Characteristics
5.4.1. Mechanical/Electrical Limitations
5.4.2. I/O Loads and Performance
5.5. Making the Storage Usable
5.5.1. Partitions/Slices
5.5.2. File Systems
5.5.3. Directory Structure
5.5.4. Enabling Storage Access
5.6. Advanced Storage Technologies
5.6.1. Network-Accessible Storage
5.6.2. RAID-Based Storage
5.6.3. Logical Volume Management
5.7. Storage Management Day-to-Day
5.7.1. Monitoring Free Space
5.7.2. Disk Quota Issues
5.7.3. File-Related Issues
5.7.4. Adding/Removing Storage
5.8. A Word About Backups…
5.9. Red Hat Enterprise Linux-Specific Information
5.9.1. Device Naming Conventions
5.9.2. File System Basics
5.9.3. Mounting File Systems
5.9.4. Network-Accessible Storage Under Red Hat Enterprise Linux
5.9.5. Mounting File Systems Automatically with /etc/fstab
5.9.6. Adding/Removing Storage
5.9.7. Implementing Disk Quotas
5.9.8. Creating RAID Arrays
5.9.9. Day to Day Management of RAID Arrays
5.9.10. Logical Volume Management
5.10. Additional Resources
5.10.1. Installed Documentation
5.10.2. Useful Websites
5.10.3. Related Books
6. Managing User Accounts and Resource Access
6.1. Managing User Accounts
6.1.1. The Username
6.1.2. Passwords
6.1.3. Access Control Information
6.1.4. Managing Accounts and Resource Access Day-to-Day
6.2. Managing User Resources
6.2.1. Who Can Access Shared Data
6.2.2. Where Users Access Shared Data
6.2.3. What Barriers Are in Place To Prevent Abuse of Resources
6.3. Red Hat Enterprise Linux-Specific Information
6.3.1. User Accounts, Groups, and Permissions
6.3.2. Files Controlling User Accounts and Groups
6.3.3. User Account and Group Applications
6.4. Additional Resources
6.4.1. Installed Documentation
6.4.2. Useful Websites
6.4.3. Related Books
7. Printers and Printing
7.1. Types of Printers
7.1.1. Printing Considerations
7.2. Impact Printers
7.2.1. Dot-Matrix Printers
7.2.2. Daisy-Wheel Printers
7.2.3. Line Printers
7.2.4. Impact Printer Consumables
7.3. Inkjet Printers
7.3.1. Inkjet Consumables
7.4. Laser Printers
7.4.1. Color Laser Printers
7.4.2. Laser Printer Consumables
7.5. Other Printer Types
7.6. Printer Languages and Technologies
7.7. Networked Versus Local Printers
7.8. Red Hat Enterprise Linux-Specific Information
7.9. Additional Resources
7.9.1. Installed Documentation
7.9.2. Useful Websites
7.9.3. Related Books
8. Planning for Disaster
8.1. Types of Disasters
8.1.1. Hardware Failures
8.1.2. Software Failures
8.1.3. Environmental Failures
8.1.4. Human Errors
8.2. Backups
8.2.1. Different Data: Different Backup Needs
8.2.2. Backup Software: Buy Versus Build
8.2.3. Types of Backups
8.2.4. Backup Media
8.2.5. Storage of Backups
8.2.6. Restoration Issues
8.3. Disaster Recovery
8.3.1. Creating, Testing, and Implementing a Disaster Recovery Plan
8.3.2. Backup Sites: Cold, Warm, and Hot
8.3.3. Hardware and Software Availability
8.3.4. Availability of Backups
8.3.5. Network Connectivity to the Backup Site
8.3.6. Backup Site Staffing
8.3.7. Moving Back Toward Normalcy
8.4. Red Hat Enterprise Linux-Specific Information
8.4.1. Software Support
8.4.2. Backup Technologies
8.5. Additional Resources
8.5.1. Installed Documentation
8.5.2. Useful Websites
8.5.3. Related Books
A. Revision History
Index