Debian Administration Training Course

Debian Distribution

Understanding Debian

• Selecting the appropriate Debian version
• Accessing Debian support and resources
• Engaging with the Debian community

Console Fundamentals

• Navigating the shell prompt
• Managing the shell prompt within X
• Utilizing the root account and root shell prompt (su, sudo, and executing programs as root in X)
• Graphical system administration tools
• Using virtual consoles
• Exiting the command prompt
• Shutting down the system
• Restoring a functional console
• Recommended additional packages for beginners
• Creating an extra user account
• Configuring sudo

The File System

• File system permissions
• Controlling permissions for new files: umask
• Group-based user permissions
• Understanding timestamps
• Working with links
• Using named pipes (FIFOs)
• Managing sockets
• Handling device files
• Working with special device files
• Navigating procfs and sysfs

Midnight Commander (MC)

• Customizing MC
• Launching MC
• Using the file manager in MC
• Advanced command-line techniques in MC
• Utilizing the internal editor in MC
• Utilizing the internal viewer in MC
• Enabling auto-start features of MC
• Navigating the FTP virtual file system in MC

The Basic Unix-like Work Environment

• The login shell
• Customizing bash
• Using special key strokes
• Navigating with the pager
• Setting a default text editor
• Exiting vim
• Logging shell activities
• Essential Unix commands

Basic Shell Commands

• Command execution and environment variables
• The "$LANG" variable
• The "$PATH" variable
• The "$HOME" variable
• Using command-line options
• Understanding shell globbing
• Interpreting command return values
• Constructing command sequences and shell redirection
• Creating command aliases

Unix-like Text Processing

• Using Unix text tools
• Mastering regular expressions
• Using replacement expressions
• Performing global substitutions with regular expressions
• Extracting data from text file tables
• Writing script snippets for piping commands

Debian Package Management

Prerequisites for Debian Package Management

• Configuring packages
• Essential precautions
• Navigating continuous upgrades
• Understanding the Debian archive basics
• Managing package dependencies
• Understanding the package management event flow
• Initial troubleshooting responses

Basic Package Management Operations

• Comparing apt-get/apt-cache with aptitude
• Performing basic operations via the command line
• Interactive use of aptitude
• Understanding aptitude key bindings
• Navigating package views in aptitude
• Utilizing search method options in aptitude
• Applying the aptitude regex formula
• Resolving dependencies in aptitude
• Reviewing package activity logs

Examples of aptitude Operations

• Listing packages using regex matching on package names
• Browsing using regex matching
• Permanently purging removed packages
• Managing auto/manual installation status
• Performing system-wide upgrades

Advanced Package Management Operations

• Executing advanced operations via the command line
• Verifying installed package files
• Precautions against package issues
• Searching package metadata

Internals of Debian Package Management

• Understanding archive metadata
• The top-level "Release" file and authenticity
• Archive-level "Release" files
• Fetching package metadata
• Package state for APT
• Package state for aptitude
• Maintaining local copies of fetched packages
• Debian package file naming conventions
• Using the dpkg command
• Using the update-alternatives command
• Using the dpkg-statoverride command
• Using the dpkg-divert command

Recovering from a Broken System

• Handling incompatibility with old user configurations
• Managing overlapping files from different packages
• Fixing broken package scripts
• Using dpkg for rescue operations
• Recovering package selection data

Tips for Package Management

• Selecting appropriate Debian packages
• Managing packages from mixed archive sources
• Adjusting candidate versions
• Handling updates and backports
• Automating package downloads and upgrades
• Limiting APT download bandwidth
• Performing emergency downgrades
• Identifying package uploaders
• Using the equivs package
• Porting packages to stable systems
• Configuring a proxy server for APT
• Creating a small public package archive
• Recording and copying system configurations
• Converting or installing alien binary packages
• Extracting packages without dpkg
• Recommended further reading for package management

System Initialization

• Overview of the boot process
• BIOS, boot loaders, and mini-Debian systems
• Understanding runlevels
• Configuring runlevels
• Examples of runlevel management
• Default parameters for each init script
• Setting the hostname
• Managing the file system
• Initializing network interfaces
• Initializing network services
• Viewing system messages
• Viewing kernel messages
• Using the udev system
• Initializing kernel modules

Authentication and Security

• Standard Unix authentication
• Managing account and password information
• Creating strong passwords
• Generating encrypted passwords
• Understanding PAM and NSS
• Configuration files accessed by PAM and NSS
• Modern centralized system management
• Understanding why GNU su does not support the wheel group
• Implementing stricter password rules
• Additional access controls
• Using sudo
• Implementing SELinux and AppArmor
• Restricting access to specific server services
• Ensuring authentication security
• Sending passwords securely over the Internet
• Using Secure Shell
• Additional security measures for the Internet
• Securing the root password

Network Setup

Basic Network Infrastructure

• Understanding domain names
• Hostname resolution
• Naming network interfaces
• Defining LAN network address ranges
• Network device support

Modern Desktop Network Configuration

• Using GUI network configuration tools

Low-Level Network Configuration

• Using iproute2 commands
• Performing safe low-level network operations

Network Optimization

• Finding the optimal MTU
• Setting the MTU
• Optimizing WAN TCP performance

Netfilter Infrastructure

Network Applications

The Mail System

• Fundamentals of modern mail services
• Mail configuration strategies for workstations

Mail Transport Agent (MTA) and Mail User Agent (MUA)

• Overview of exim4
• Basic MUA: Mutt

Mail Delivery Agent (MDA) with Filtering

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Servers

Remote Access Servers and Utilities (SSH)

• SSH fundamentals
• Setting up port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Interacting with non-standard SSH clients
• Configuring ssh-agent
• Shutting down remote systems via SSH
• SSH troubleshooting

Other Network Application Servers

Other Network Application Clients

Diagnosing System Daemons

The X Window System

• Setting up the desktop environment
• Understanding the server/client relationship
• Configuring the X server
• Starting the X Window System
• Starting an X session with gdm
• Customizing X sessions (classic method)
• Customizing X sessions (new method)
• Connecting remote X clients via SSH
• Securing X terminals over the Internet
• Using X applications
• X office applications
• X utility applications

System Tips

The Screen Program

• Use cases for screen(1)
• Key bindings for the screen command

Data Recording and Presentation

• Understanding the log daemon
• Using log analyzers
• Cleanly recording shell activities
• Customizing text data display
• Customizing time and date display
• Colorizing shell echo
• Colorizing commands
• Recording editor activities for complex repetitions
• Recording X application graphic images
• Recording changes in configuration files

Data Storage Tips

• Configuring disk partitions
• Accessing partitions using UUID
• Configuring file systems
• Creating and checking file system integrity
• Optimizing file systems via mount options
• Optimizing file systems via superblocks
• Optimizing hard disk performance
• Using SMART to predict hard disk failure
• Expanding storage space via LVM
• Expanding storage space by mounting additional partitions
• Expanding storage space using symlinks
• Expanding storage space using aufs

Data Encryption Tips

• Encrypting removable disks with dm-crypt/LUKS
• Creating encrypted swap partitions with dm-crypt
• Automatically encrypting files with eCryptfs
• Automatically mounting eCryptfs

Monitoring, Controlling, and Starting Program Activities

• Timing a process
• Understanding scheduling priority
• Using the ps command
• Using the top command
• Listing files opened by a process
• Tracing program activities
• Identifying processes using files or sockets
• Repeating commands at constant intervals
• Repeating commands over files
• Starting programs from the GUI
• Customizing startup programs
• Killing a process
• Scheduling one-time tasks
• Scheduling regular tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Identifying logged-in users
• Notifying all users
• Identifying hardware
• Configuring hardware
• Managing system and hardware time
• Configuring terminals
• Setting up the sound infrastructure
• Disabling the screen saver
• Disabling beep sounds
• Monitoring memory usage
• Performing system security and integrity checks

The Kernel

• Understanding kernel parameters
• Understanding kernel headers
• Compiling the kernel and related modules
• Compiling kernel source: Debian standard method
• Compiling module source: Debian standard method
• Handling non-free hardware drivers

Virtualized Systems

• Virtualization tools
• Virtualization workflows
• Mounting virtual disk image files
• Using chroot systems
• Managing multiple desktop systems

Data Management

Sharing, Copying, and Archiving

• Archive and compression tools
• Copy and synchronization tools
• Archive idioms
• Copy idioms
• File selection idioms
• Backup and recovery strategies
• Backup utility suites
• Example script for system backup
• Script for data backup
• Using removable storage devices
• Sharing data via network
• Archive media

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting disk
• Understanding data redundancy
• Data file recovery and forensic analysis
• Splitting large files into smaller ones
• Clearing file contents
• Creating dummy files
• Erasing an entire hard disk
• Erasing unused areas of a hard disk
• Undeleting deleted but still open files
• Searching for all hard links
• Identifying invisible disk space consumption

Data Security Infrastructure

• Key management for GnuPG (signing and encrypting)
• Using MD5 sums