Debian Administration Training Course

Debian Distribution

Understanding Debian

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

Console Fundamentals

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

The Filesystem

• Understanding filesystem permissions
• Controlling permissions for new files: umask
• Managing permissions for user groups
• Understanding timestamps
• Working with links
• Using named pipes (FIFOs)
• Utilizing sockets
• Handling device files
• Managing special device files
• Navigating procfs and sysfs

Midnight Commander (MC)

• Customizing MC
• Launching MC
• Using the file manager in MC
• Command-line techniques in MC
• Utilizing the internal editor in MC
• Utilizing the internal viewer in MC
• Configuring auto-start features of MC
• Using the FTP virtual filesystem in MC

The Basic Unix-like Work Environment

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

Simple Shell Commands

• Command execution and environment variables
• The "$LANG" variable
• The "$PATH" variable
• The "$HOME" variable
• Understanding command line options
• Using shell globbing
• Interpreting the return value of a command
• Managing typical command sequences and shell redirection
• Creating command aliases

Unix-like Text Processing

• Utilizing Unix text tools
• Working with regular expressions
• Understanding replacement expressions
• Performing global substitution 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
• Managing the cycle of perpetual upgrades
• Understanding the Debian archive basics
• Understanding package dependencies
• Tracing the event flow of package management
• Initial responses to package management issues

Basic Package Management Operations

• Comparing apt-get/apt-cache vs. aptitude
• Performing basic package management operations via the command line
• Using aptitude interactively
• Mastering key bindings of aptitude
• Navigating package views in aptitude
• Exploring search method options with aptitude
• Understanding the aptitude regex formula
• Resolving dependencies with 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
• Organizing auto/manual installation status
• Performing a system-wide upgrade

Advanced Package Management Operations

• Executing advanced package management operations via the command line
• Verifying installed package files
• Implementing safeguards for package problems
• Searching package metadata

Internals of Debian Package Management

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

Recovery from a Broken System

• Addressing incompatibilities with old user configurations
• Handling different packages with overlapping files
• Fixing broken package scripts
• Rescuing with the dpkg command
• Recovering package selection data

Tips for Package Management

• Selecting Debian packages
• Handling packages from mixed archive sources
• Tweaking candidate versions
• Managing Updates and Backports
• Automatically downloading and upgrading packages
• Limiting download bandwidth for APT
• Performing emergency downgrades
• Identifying the package uploader
• Using the equivs package
• Porting packages to the stable system
• Configuring a proxy server for APT
• Utilizing a small public package archive
• Recording and copying system configuration
• Converting or installing alien binary packages
• Extracting packages without dpkg
• Additional reading resources for package management

The System Initialization

• Overview of the boot strap process
• Understanding BIOS, boot loader, and mini-Debian system
• Understanding the concept of runlevels
• Configuring runlevels
• Runlevel management examples
• Default parameters for each init script
• Configuring the hostname
• Managing the filesystem
• Initializing network interfaces
• Initializing network services
• Managing system messages
• Monitoring 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 rules
• Other access control mechanisms
• Using sudo
• Understanding SELinux and Apparmor
• Restricting access to specific server services
• Ensuring authentication security
• Sending secure passwords over the Internet
• Utilizing Secure Shell
• Implementing additional security measures for the Internet
• Securing the root password

Network Setup

The Basic Network Infrastructure

• Understanding the domain name
• Configuring hostname resolution
• Identifying the network interface name
• Defining the network address range for the LAN
• Understanding network device support

Modern Network Configuration for Desktops

• Using GUI network configuration tools

Low-Level Network Configuration

• Using Iproute2 commands
• Safely performing low-level network operations

Network Optimization

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

Netfilter Infrastructure

Network Applications

The Mail System

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

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

• Overview of exim4
• Basic MUA - Mutt

Mail Delivery Agent (MDA) with Filter

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Server

The 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 the remote system 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
• Working with the X server
• Starting the X Window System
• Starting an X session with gdm
• Customizing the X session (classic method)
• Customizing the X session (new method)
• Connecting a remote X client via SSH
• Using a secure X terminal over the Internet
• Using X applications
• Using X office applications
• Using X utility applications

System Tips

The screen Program

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

Data Recording and Presentation

• Utilizing the log daemon
• Using log analyzers
• Cleanly recording shell activities
• Customizing text data display
• Customizing time and date display
• Colorized shell echo
• Colorized commands
• Recording editor activities for complex repetitions
• Recording the graphic image of an X application
• Recording changes in configuration files

Data Storage Tips

• Configuring disk partitions
• Accessing partitions using UUID
• Configuring the filesystem
• Creating filesystems and performing integrity checks
• Optimizing the filesystem via mount options
• Optimizing the filesystem via superblock
• Optimizing the hard disk
• Using SMART to predict hard disk failure
• Expanding usable storage space via LVM
• Expanding usable storage space by mounting another partition
• Expanding usable storage space using symlinks
• Expanding usable storage space using aufs

Data Encryption Tips

• Encrypting removable disks with dm-crypt/LUKS
• Encrypting the swap partition 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 a command at a constant interval
• Repeating a command looping over files
• Starting a program from the GUI
• Customizing programs to be started
• Killing a process
• Scheduling one-time tasks
• Scheduling regular tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Identifying who is on the system
• Warning all users
• Identifying hardware
• Configuring hardware
• Managing system and hardware time
• Configuring the terminal
• Understanding the sound infrastructure
• Disabling the screen saver
• Disabling beep sounds
• Monitoring memory usage
• Checking system security and integrity

The Kernel

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

Virtualized System

• Using virtualization tools
• Understanding the virtualization workflow
• Mounting the virtual disk image file
• Using the Chroot system
• Managing multiple desktop systems

Data Management

Sharing, Copying, and Archiving

• Using archive and compression tools
• Using copy and synchronization tools
• Idioms for archiving
• Idioms for copying
• Idioms for file selection
• Backup and recovery
• Using backup utility suites
• Example script for system backup
• Cop script for data backup
• Managing removable storage devices
• Sharing data via network
• Using archive media

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting the disk
• Ensuring data redundancy
• Data file recovery and forensic analysis
• Splitting large files into smaller files
• 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 all hardlinks
• Monitoring invisible disk space consumption

Data Security Infrastructure

• Key management for GnuPG (signing and encrypting)
• Understanding the MD5 sum