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
• Using the shell prompt within the X environment
• Managing the root account and root shell prompt (utilizing su, sudo, and running programs as root in X)
• Utilizing GUI system administration tools
• Working with virtual consoles
• Exiting the command prompt effectively
• Properly shutting down the system
• Restoring console functionality
• Recommended packages for beginners
• Setting up an additional user account
• Configuring sudo

File System Management

• Understanding file system permissions
• Managing permissions for new files using umask
• Handling group permissions for user groups
• Understanding file timestamps
• Working with links
• Utilizing named pipes (FIFOs)
• Managing sockets
• Working with device files
• Handling special device files
• Navigating procfs and sysfs

Midnight Commander (MC)

• Customizing MC settings
• Launching MC
• Using the file manager within MC
• Advanced command-line techniques in MC
• Using MC's internal editor
• Using MC's internal viewer
• Utilizing MC's auto-start features
• Accessing the FTP virtual filesystem in MC

Basic Unix-like Work Environment

• Understanding the login shell
• Customizing the bash shell
• Using special key strokes
• Utilizing the pager
• Setting a default text editor
• Exiting vim
• Logging shell activities
• Mastering basic Unix commands

Essential Shell Commands

• Command execution and environment variables
• Understanding the "$LANG" variable
• Understanding the "$PATH" variable
• Understanding the "$HOME" variable
• Using command line options
• Utilizing shell globbing
• Interpreting command return values
• Employing typical command sequences and shell redirection
• Creating command aliases

Unix-like Text Processing

• Working with Unix text tools
• Understanding regular expressions
• Using replacement expressions
• Performing global substitution with regular expressions
• Extracting data from text files
• Utilizing script snippets for command piping

Debian Package Management

Prerequisites for Debian Package Management

• Configuring packages
• Essential precautions
• Managing continuous upgrades
• Basics of the Debian archive
• Understanding package dependencies
• The lifecycle of package management
• Initial steps for resolving package issues

Basic Package Management Operations

• Comparing apt-get/apt-cache with aptitude
• Executing basic package management operations via the command line
• Interactive usage of aptitude
• Using aptitude key bindings
• Navigating package views in aptitude
• Search options with aptitude
• Using aptitude regex patterns
• Resolving dependencies with aptitude
• Reviewing package activity logs

Examples of aptitude Operations

• Listing packages using regex matching on names
• Browsing packages with regex matching
• Permanently purging removed packages
• Managing auto/manual install statuses
• Performing a system-wide upgrade

Advanced Package Management Operations

• Executing advanced package management tasks via the command line
• Verifying installed package files
• Protecting against package issues
• Searching package metadata

Debian Package Management Internals

• Understanding archive metadata
• Analyzing the top-level "Release" file and authenticity
• Examining archive-level "Release" files
• Fetching package metadata
• Understanding package state in APT
• Understanding package state in aptitude
• Managing local copies of fetched packages
• Understanding Debian package file naming conventions
• Utilizing the dpkg command
• Utilizing the update-alternatives command
• Utilizing the dpkg-statoverride command
• Utilizing the dpkg-divert command

Recovering from a Broken System

• Addressing compatibility issues with old user configurations
• Resolving overlapping files from different packages
• Fixing broken package scripts
• Rescuing the system with the dpkg command
• Recovering package selection data

Tips for Package Management

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

System Initialization

• Overview of the bootstrap process
• BIOS, boot loaders, and mini-Debian systems
• Understanding runlevels
• Configuring runlevels
• Examples of runlevel management
• Default parameters for init scripts
• Setting the hostname
• Managing the file system
• Initializing network interfaces
• Initializing network services
• Viewing system messages
• Viewing kernel messages
• Understanding 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 used by PAM and NSS
• Modern centralized system management
• Understanding GNU su and the wheel group
• Enforcing stricter password rules
• Implementing additional access controls
• Utilizing sudo
• Working with SELinux and AppArmor
• Restricting access to specific server services
• Ensuring authentication security
• Securing passwords over the Internet
• Using Secure Shell (SSH)
• Implementing additional Internet security measures
• Securing the root password

Network Setup

Basic Network Infrastructure

• Understanding domain names
• Configuring hostname resolution
• Identifying network interface names
• Defining LAN network address ranges
• Supporting network devices

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

Netfilter Infrastructure

Network Applications

Mail Systems

• Basics 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 Filters

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Servers

Remote Access Server and Utilities (SSH)

• SSH fundamentals
• Port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Handling incompatible SSH clients
• Configuring ssh-agent
• Shutting down remote systems via SSH
• Troubleshooting SSH

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 (modern method)
• Connecting to 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 output
• Colorizing command outputs
• Recording editor activities for repetitive tasks
• Recording graphic images of X applications
• Recording changes in configuration files

Data Storage Tips

• Configuring disk partitions
• Accessing partitions using UUIDs
• Configuring file systems
• Creating and checking file system integrity
• Optimizing file systems via mount options
• Optimizing file systems via superblock
• Optimizing hard disk performance
• Using SMART to predict hard disk failures
• Expanding usable storage space via LVM
• Expanding storage by mounting another partition
• Expanding storage using symlinks
• Expanding storage using AUFS

Data Encryption Tips

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

Monitoring, Controlling, and Starting Program Activities

• Timing a process
• Adjusting 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 a command at constant intervals
• Repeating a command over files
• Starting programs from the GUI
• Customizing program startup
• Killing a process
• Scheduling one-time tasks
• Scheduling recurring tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Identifying users on the system
• Broadcasting warnings to all users
• Identifying hardware
• Configuring hardware
• Managing system and hardware time
• Configuring the terminal
• Setting up the sound infrastructure
• Disabling the screen saver
• Disabling beep sounds
• Monitoring memory usage
• Performing system security and integrity checks

The Kernel

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

Virtualized Systems

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

Data Management

Sharing, Copying, and Archiving

• Using archive and compression tools
• Using 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 copying
• Handling removable storage devices
• Sharing data over the network
• Using archive media

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting the 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