The Linux System Administrators' Guide

Version 0.6.2

Lars Wirzenius

Joanna Oja

An introduction to system administration of a Linux system for novices.

Copyright 1993--1998 Lars Wirzenius.

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Table of Contents
Source and pre-formatted versions available
1. Introduction
The Linux Documentation Project
2. Overview of a Linux System
Various parts of an operating system
Important parts of the kernel
Major services in a UNIX system
Logins from terminals
Periodic command execution: cron and at
Graphical user interface
Network logins
Network file systems
The filesystem layout
3. Overview of the Directory Tree
The root filesystem
The /etc directory
The /dev directory
The /usr filesystem
The /var filesystem
The /proc filesystem
4. Using Disks and Other Storage Media
Two kinds of devices
Hard disks
The MBR, boot sectors and partition table
Extended and logical partitions
Partition types
Partitioning a hard disk
Device files and partitions
What are filesystems?
Filesystems galore
Which filesystem should be used?
Creating a filesystem
Mounting and unmounting
Checking filesystem integrity with fsck
Checking for disk errors with badblocks
Fighting fragmentation
Other tools for all filesystems
Other tools for the ext2 filesystem
Disks without filesystems
Allocating disk space
Partitioning schemes
Space requirements
Examples of hard disk allocation
Adding more disk space for Linux
Tips for saving disk space
5. Memory Management
What is virtual memory?
Creating a swap space
Using a swap space
Sharing swap spaces with other operating systems
Allocating swap space
The buffer cache
6. Boots And Shutdowns
An overview of boots and shutdowns
The boot process in closer look
More about shutdowns
Single user mode
Emergency boot floppies
7. init
init comes first
Configuring init to start getty: the /etc/inittab file
Run levels
Special configuration in /etc/inittab
Booting in single user mode
8. Logging In And Out
Logins via terminals
Logins via the network
What login does
X and xdm
Access control
Shell startup
9. Managing user accounts
What's an account?
Creating a user
/etc/passwd and other informative files
Picking numeric user and group ids
Initial environment: /etc/skel
Creating a user by hand
Changing user properties
Removing a user
Disabling a user temporarily
10. Backups
On the importance of being backed up
Selecting the backup medium
Selecting the backup tool
Simple backups
Making backups with tar
Restoring files with tar
Multilevel backups
What to back up
Compressed backups
11. Keeping Time
Time zones
The hardware and software clocks
Showing and setting time
When the clock is wrong
Glossary (DRAFT)