Debian Administration Training Course

Debian Distribution

Introduction to Debian

• Selecting a Debian version
• Debian support resources and assistance
• The Debian community

Console fundamentals

• Understanding the shell prompt
• Using the shell prompt within the X environment
• Root account access and the root shell prompt (su, sudo, executing programs as root in X)
• GUI-based system administration tools
• Virtual consoles
• Exiting the command prompt
• System shutdown procedures
• Restoring a functional console state
• Recommended additional packages for beginners
• Creating an additional user account
• Configuring sudo

The filesystem

• Filesystem permission controls
• Managing permissions for new files via umask
• Group-based permissions
• Timestamps
• Symbolic and hard links
• Named pipes (FIFOs)
• Sockets
• Device files
• Special device files
• The procfs and sysfs virtual filesystems

Midnight Commander (MC)

• Customizing MC
• Launching MC
• Using the file manager in MC
• Command-line shortcuts within MC
• The built-in editor in MC
• The built-in viewer in MC
• MC auto-start capabilities
• The FTP virtual filesystem in MC

Essential Unix-like work environment

• Understanding the login shell
• Customizing bash
• Special key combinations
• Using 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
• Command-line options
• Shell globbing
• Command return values
• Standard command sequences and shell redirection
• Command aliases

Unix-like text processing

• Unix text utilities
• Regular expressions
• Replacement patterns
• Global substitution using regular expressions
• Extracting data from text file tables
• Script snippets for command piping

Debian package management

Prerequisites for Debian package management

• Package configuration
• Basic safety precautions
• Managing continuous upgrades
• Debian archive fundamentals
• Package dependencies
• The workflow of package management events
• Initial troubleshooting for package management issues

Essential package management tasks

• Comparing apt-get/apt-cache with aptitude
• Basic package management via the command line
• Interactive use of aptitude
• aptitude key bindings
• Package views in aptitude
• Search options in aptitude
• aptitude regular expression formulas
• Dependency resolution in aptitude
• Package activity logs

aptitude operation examples

• Listing packages using regex matching on names
• Browsing packages with regex matching
• Permanently purging removed packages
• Managing auto/manual install status
• System-wide upgrades

Advanced package management tasks

• Advanced package management via command line
• Verifying installed package files
• Mitigating package issues
• Searching package metadata

Internals of Debian package management

• Archive metadata
• The top-level "Release" file and authenticity
• Archive-level "Release" files
• Fetching package metadata
• Package state in APT
• Package state in aptitude
• Local caching of downloaded packages
• Debian package naming conventions
• The dpkg command
• The update-alternatives command
• The dpkg-statoverride command
• The dpkg-divert command

Recovering from system breakage

• Resolving incompatibilities with old user configurations
• Handling packages with overlapping files
• Fixing broken package scripts
• Rescue operations using dpkg
• Restoring package selection data

Package management tips

• Criteria for selecting Debian packages
• Using packages from mixed archive sources
• Adjusting candidate versions
• Managing updates and Backports
• Automated package download and upgrade
• Limiting APT download bandwidth
• Emergency package downgrades
• Identifying package uploaders
• Using the equivs package
• Porting packages to stable systems
• Configuring a proxy server for APT
• Setting up a small public package archive
• Recording and replicating system configurations
• Converting or installing foreign binary packages
• Extracting packages without dpkg
• Further reading on package management

System initialization

• Overview of the boot strap process
• BIOS, boot loaders, and mini-Debian systems
• Understanding runlevels
• Configuring runlevels
• Runlevel management examples
• Default parameters for init scripts
• Hostname configuration
• Filesystem mounting
• Network interface initialization
• Network service startup
• System messages
• Kernel messages
• The udev system
• Kernel module initialization

Authentication and Security

• Standard Unix authentication
• Managing account and password details
• Creating strong passwords
• Generating encrypted passwords
• PAM and NSS frameworks
• Configuration files for PAM and NSS
• Modern centralized system management
• Why GNU su does not support the wheel group
• Enforcing stricter password policies
• Additional access controls
• Using sudo
• SELinux and AppArmor
• Restricting access to server services
• Authentication security
• Securing passwords over the Internet
• Secure Shell (SSH)
• Additional Internet security measures
• Securing the root password

Network setup

Basic network infrastructure

• Domain names
• Hostname resolution
• Network interface naming
• LAN network address ranges
• Network device support

Modern desktop network configuration

• GUI-based network configuration tools

Low-level network configuration

• Iproute2 commands
• Safe low-level network operations

Network optimization

• Determining optimal MTU
• Setting MTU values
• WAN TCP optimization

Netfilter infrastructure

Network applications

The mail system

• Modern mail service basics
• Mail configuration strategy for workstations

Mail transport agent (MTA) and Mail user agent (MUA)

• Overview of exim4
• Basic MUA usage with Mutt

Mail delivery agent (MDA) with filters

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 servers

Remote access servers and utilities (SSH)

• SSH fundamentals
• Port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Managing 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
• 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 (modern method)
• Connecting remote X clients 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
• Colorized shell echo
• Colorized command output
• Recording editor activities for complex repetitions
• Capturing graphical images of X applications
• Tracking changes in configuration files

Data storage tips

• Disk partition configuration
• Accessing partitions using UUID
• Filesystem configuration
• Filesystem creation and integrity checks
• Filesystem optimization via mount options
• Filesystem optimization via superblocks
• Hard disk optimization
• Using SMART to predict hard disk failures
• Expanding usable storage space with LVM
• Expanding storage by mounting additional partitions
• Expanding storage using symbolic links
• 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 processes
• Scheduling priorities
• The ps command
• The top command
• Listing files opened by processes
• Tracing program activities
• Identifying processes using files or sockets
• Executing commands at constant intervals
• Executing commands in loops over files
• Starting programs from the GUI
• Customizing startup programs
• Terminating processes
• Scheduling one-time tasks
• Scheduling recurring tasks
• The Alt-SysRq key

System maintenance tips

• Identifying logged-in users
• Broadcasting system warnings
• Hardware identification
• Hardware configuration
• System and hardware time synchronization
• Terminal configuration
• The sound infrastructure
• Disabling screen savers
• Disabling beep sounds
• Memory usage analysis
• 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 workflows
• Mounting virtual disk image files
• The Chroot system
• Managing multiple desktop systems

Data management

Sharing, copying, and archiving

• Archive and compression tools
• Copy and synchronization tools
• Archiving idioms
• Copying idioms
• File selection idioms
• Backup and recovery
• Backup utility suites
• System backup script examples
• Data backup copy scripts
• Removable storage devices
• Sharing data over 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 chunks
• Clearing file contents
• Creating dummy files
• Erasing entire hard disks
• Erasing unused hard disk areas
• Undeleting deleted but still open files
• Finding all hard links
• Identifying invisible disk space consumption

Data security infrastructure

• GnuPG key management (signing and encryption)
• MD5 checksums