Debian Administration Training Course

Debian Distribution

What is Debian?

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

Console Fundamentals

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

The Filesystem

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

Midnight Commander (MC)

• Customizing MC
• Launching MC
• Using the file manager within MC
• Applying command-line tricks in MC
• Using MC's internal editor
• Using MC's internal viewer
• Leveraging MC's auto-start features
• Using MC's FTP virtual filesystem

The Basic Unix-like Work Environment

• Configuring the login shell
• Customizing bash
• Utilizing special key strokes
• Using 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 "$LANG" variable
• Understanding the "$PATH" variable
• Understanding the "$HOME" variable
• Using command line options
• Utilizing shell globbing
• Checking the return value of a command
• Creating typical command sequences and using 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
• Implementing basic precautions
• Managing continuous upgrades
• Understanding Debian archive basics
• Understanding package dependencies
• Understanding the event flow of package management
• Initial responses to package management issues

Basic Package Management Operations

• Comparing apt-get/apt-cache with aptitude
• Performing basic package management operations via the command line
• Using aptitude interactively
• Utilizing key bindings in aptitude
• Viewing packages in aptitude
• Configuring search options in aptitude
• Using aptitude regex formulas
• Resolving dependencies in aptitude
• Accessing package activity logs

Examples of aptitude Operations

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

Advanced Package Management Operations

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

Internals of Debian Package Management

• Archive metadata
• Top-level "Release" file and authenticity
• Archive-level "Release" files
• Fetching package metadata
• Package state for APT
• Package state for aptitude
• 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
• Resolving overlapping files in different packages
• Fixing broken package scripts
• Using dpkg for rescue operations
• 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 downloads and upgrades
• Limiting APT download bandwidth
• Performing emergency downgrades
• Identifying package uploaders
• Using the equivs package
• Porting packages to a stable system
• Configuring an APT proxy server
• Managing a small public package archive
• Recording and copying system configurations
• Converting or installing alien binary packages
• Extracting packages without dpkg
• Further reading on package management

System Initialization

• Overview of the bootstrap process
• BIOS, boot loaders, and the mini-Debian system
• Understanding runlevels
• Configuring runlevels
• Examples of runlevel management
• Default parameters for init scripts
• Setting the hostname
• Mounting the filesystem
• Initializing network interfaces
• Initializing network services
• Managing system messages
• Managing kernel messages
• Configuring the udev system
• Initializing kernel modules

Authentication and Security

• Standard Unix authentication
• Managing account and password information
• Creating strong passwords
• Creating encrypted passwords
• Understanding PAM and NSS
• Configuring files accessed by PAM and NSS
• Implementing modern centralized system management
• Understanding why GNU su does not support the wheel group
• Enforcing stricter password rules
• Implementing other access controls
• Using sudo
• Configuring SELinux and Apparmor
• Restricting access to specific server services
• Securing authentication mechanisms
• Ensuring secure password transmission over the Internet
• Configuring Secure Shell (SSH)
• Implementing additional security measures for the Internet
• Securing the root password

Network Setup

Basic Network Infrastructure

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

Modern Desktop Network Configuration

• Using GUI network configuration tools

Low-Level Network Configuration

• Using Iproute2 commands
• Executing safe low-level network operations

Network Optimization

• Determining the optimal MTU
• Configuring the MTU
• Optimizing WAN TCP

Netfilter Infrastructure

Network Applications

The Mail System

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

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

• Overview of exim4
• Basic MUA using Mutt

Mail Delivery Agent (MDA) with Filters

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Server

Remote Access Server and Utility (SSH)

• SSH fundamentals
• Port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Managing 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 the X session (classic method)
• Customizing the X session (new method)
• Connecting a remote X client via SSH
• Securing X terminals over the Internet
• Utilizing 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

• Using the log daemon
• Using log analyzers
• Cleanly recording shell activities
• Customizing text data display
• Customizing time and date display
• Using colorized shell echo
• Using colorized commands
• Recording editor activities for complex repeats
• Recording the graphical 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 hard disk performance
• 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 swap partitions with dm-crypt
• Automatically encrypting files with eCryptfs
• Automatically mounting eCryptfs

Monitoring, Controlling, and Starting Program Activities

• Timing a process
• Setting 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 in a loop over files
• Starting a program from the GUI
• Customizing program startup
• Killing a process
• Scheduling one-time tasks
• Scheduling recurring tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Monitoring who is on the system
• Broadcasting warnings to all users
• Identifying hardware
• Configuring hardware
• Managing system and hardware time
• Configuring the terminal
• Configuring 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: Debian standard method
• Compiling module source: Debian standard method
• Managing non-free hardware drivers

Virtualized System

• Using virtualization tools
• Virtualization workflow
• Mounting virtual disk image files
• Using chroot
• Running multiple desktop systems

Data Management

Sharing, Copying, and Archiving

• Using archive and compression tools
• Using copy and synchronization tools
• Archiving idioms
• Copying idioms
• File selection idioms
• Backup and recovery strategies
• Utilizing backup utility suites
• Example script for system backup
• Script for data backup copying
• Managing removable storage devices
• Sharing data via network
• Archive media options

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting disks
• Managing 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 for all hard links
• Identifying invisible disk space consumption

Data Security Infrastructure

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