Debian Administration Training Course

Debian Distribution

Understanding Debian

• Selecting the appropriate Debian version
• Accessing Debian support and resources
• Navigating the Debian community

Console Fundamentals

• Understanding the shell prompt
• Utilizing the shell prompt within X
• Managing the root account and root shell prompt (using su, sudo, and running programs as root under X)
• Overview of GUI system administration tools
• Working with virtual consoles
• Exiting the command prompt
• Properly shutting down the system
• Restoring a functional console
• Recommended packages for newcomers
• Creating an additional user account
• Configuring sudo

Filesystem Management

• Managing filesystem permissions
• Controlling permissions for new files via umask
• Managing group permissions for users
• Understanding timestamps
• Creating and managing links
• Utilizing named pipes (FIFOs)
• Working with sockets
• Handling device files
• Accessing special device files
• Exploring procfs and sysfs

Mastering Midnight Commander (MC)

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

Essential Unix-like Work Environment

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

Basic Shell Commands

• Command execution and environment variables
• Understanding the "$LANG" variable
• Configuring the "$PATH" variable
• Working with 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

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

Debian Package Management

Prerequisites for Debian Package Management

• Configuring packages
• Essential precautions
• Navigating ongoing upgrades
• Understanding Debian archive basics
• Managing package dependencies
• Understanding the package management workflow
• Addressing initial package management issues

Basic Package Management Operations

• Comparing apt-get/apt-cache with aptitude
• Performing basic package management via the command line
• Using aptitude interactively
• Learning key bindings in aptitude
• Navigating package views in aptitude
• Utilizing search options in aptitude
• Understanding the aptitude regex formula
• Resolving dependencies in aptitude
• Reviewing package activity logs

Examples of aptitude Operations

• Listing packages using regex matching on names
• Browsing using regex matching
• Completely purging removed packages
• Managing auto/manual installation status
• Performing a system-wide upgrade

Advanced Package Management Operations

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

Internals of Debian Package Management

• Understanding archive metadata
• Examining the top-level "Release" file and authenticity
• Understanding archive-level "Release" files
• Fetching package metadata
• Understanding package states for APT
• Understanding package states for aptitude
• Managing local copies of fetched packages
• Understanding 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

• Resolving conflicts with old user configurations
• Handling overlapping files in different packages
• Fixing broken package scripts
• Using dpkg for rescue operations
• Recovering package selection data

Package Management Tips

• 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 an APT proxy server
• Setting up a small public package archive
• Recording and copying system configurations
• Converting or installing alien binary packages
• Extracting packages without dpkg
• Recommended further reading on package management

System Initialization

• Overview of the bootstrap process
• Understanding BIOS, bootloaders, and mini-Debian systems
• Understanding runlevels
• Configuring runlevels
• Examples of runlevel management
• Default parameters for init scripts
• Managing the hostname
• Configuring the filesystem
• Initializing network interfaces
• Initializing network services
• System messages
• 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 accessed by PAM and NSS
• Modern centralized system management
• Why GNU su does not support the wheel group
• Implementing stricter password policies
• Other access control methods
• Using sudo
• Using SELinux and AppArmor
• Restricting access to specific server services
• Securing authentication
• Securing passwords over the Internet
• Using Secure Shell (SSH)
• Additional security measures for Internet exposure
• Securing the root password

Network Setup

Basic Network Infrastructure

• Understanding domain names
• Hostname resolution
• Network interface naming
• Determining LAN network address ranges
• Network device support

Modern Network Configuration for Desktops

• Using GUI network configuration tools

Low-Level Network Configuration

• Using Iproute2 commands
• Safe low-level network operations

Network Optimization

• Identifying optimal MTU
• Setting MTU values
• Optimizing WAN TCP

Netfilter Infrastructure

Network Applications

Mail Systems

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

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

• Overview of Exim4
• Basic MUA usage: Mutt

Mail Delivery Agents (MDA) with Filtering

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Servers

Remote Access Server and Utility (SSH)

• SSH basics
• Port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Handling incompatible SSH clients
• Setting up 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
• The X server
• Starting the X Window System
• Starting X sessions with GDM
• Customizing X sessions (classic method)
• Customizing X sessions (new method)
• Connecting to a remote X client via SSH
• Securing X terminals over the Internet
• 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

• The log daemon
• Log analyzers
• Cleanly recording shell activities
• Customizing text data display
• Customizing time and date display
• Colorizing shell echo outputs
• Colorizing commands
• Recording editor activities for complex repetitions
• Recording graphical images of X applications
• Recording changes in configuration files

Data Storage Tips

• Disk partition configuration
• Accessing partitions using UUIDs
• Filesystem configuration
• Creating filesystems and performing integrity checks
• Optimizing filesystems via mount options
• Optimizing filesystems via superblocks
• Hard disk optimization
• Using SMART to predict hard disk failure
• Expanding usable storage space via LVM
• Expanding usable storage space by mounting additional partitions
• Expanding usable storage space using symbolic links
• Expanding usable storage space 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 processes
• Understanding scheduling priorities
• 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 in loops over files
• Starting programs from the GUI
• Customizing startup programs
• Killing processes
• Scheduling one-time tasks
• Scheduling recurring tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Identifying logged-in users
• Broadcasting warnings to all users
• Hardware identification
• Hardware configuration
• System and hardware time synchronization
• Terminal configuration
• Sound infrastructure setup
• Disabling the screen saver
• Disabling beep sounds
• Monitoring memory usage
• System security and integrity checks

The Kernel

• Kernel parameters
• Kernel headers
• Compiling the kernel and related modules
• Compiling kernel source: Debian standard method
• Compiling module source: Debian standard method
• Non-free hardware drivers

Virtualized Systems

• Virtualization tools
• Virtualization workflow
• 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
• Idioms for archives
• Idioms for copying
• Idioms for file selection
• Backup and recovery
• Backup utility suites
• Example script for system backup
• Script for data backup copying
• Managing removable storage devices
• Sharing data via the network
• Archive media

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting disks
• 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 hardlinks
• Understanding invisible disk space consumption

Data Security Infrastructure

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