Ubuntu Tutorials - Herong's Tutorial Examples

https://www.herongyang.com/Ubuntu

© 2019-2025 Herong Yang. All rights reserved.

Ubuntu Tutorials This book is a collection of notes and sample codes written by the author while he was learning Ubuntu systems. Topics include using GNOME desktop for graphical applications; using shell for command line tools; managing processes and memory; managing files and directories; using APT (Advanced Package Tool); managing network connections; using wget and curl commands; SSH Server configuration and client tools; administrative tasks: moving /home directory, migrating users; Updated in 2025 (Version v1.25) with memory management tutorials.

Table of Contents

About This Book

Introduction to Ubuntu Systems

What is Ubuntu

hostnamectl - Display System Information

"free" - Display Free and Used Memory

"who | w" - Logged-in Users and Their Running Commands

GNOME - Desktop Interface and Environment

What Is GNOME

Keyboard Shortcuts on GNOME

gnome-tweaks - The GNOME Tweak Tool

GNOME Application - Settings

GNOME Application - Files

GNOME Application - Terminal

GNOME Application - Image Viewers

GNOME Application - Video Players

Shell - The Command-Line Interpreter

What Is Shell

What Is Bash (Bourne Again SHell)

Create and Run Bash Script

Bash Command Line Interpretation Steps

Bash Shell Session Customization

Command Input/Output Redirection

Shell Session Command History

"tmux" - Terminal Multiplexer

Process Management

"ps" - Display Current Processes

"jobs" - Manage Background Jobs

Cron Daemon, Table and Jobs

Memory Management

Layers of Memory and Access Speed

List CPU Caches and Their Sizes

Virtual Memory vs. Physical Memory

Buffer Memory and Cache Memory

Verify Cache Memory with "cp" Command

What Is Swap Space

Virtual Memory Mapping and Page Table

"ps -o rss,drs,trs,vsz,sz" - Process Status Options

smem - Process Memory Usage Report

pmap - Process Memory Map

/proc/{id}/maps - Process Memory Map

/proc/{id}/smaps - Process Memory Map Details

earlyoom - A Simple OOM Killer

Files and Directories

"find" - Search for Files

"more", "head" and "cat" - Read Files

"split" and "cat" - Split and Join Files

Truncate Log Files

"compress/uncompress" - Compressed *.Z Files

"gzip/gunzip" - Compressed *.gz Files

"xz/unxz" - Compressed *.xz or *.lzma Files

"tar -c" and "tar -x" - Create and Extract Archive Files

"zip" and "unzip" - Create and Extract ZIP Files

"rar" and "unrar" - Roshal Archive Files

APT (Advanced Package Tool)

What Is APT

"apt list" - List Software Packages

"apt show" - Show Software Package Details

"sudo apt install/remove" - Install/Remove Package

"sudo apt autoremove" - Remove Unneeded Packages

Manage "apt" Package Repositories

APT Configuration Settings and Overrides

APT Package Archives and Metadata

Network Connection on Ubuntu

Connect to Wi-Fi with GNOME Settings

"traceroute" - Trace Route to Remote Host

"ifconfig" - Trace Routes to Remote Host

"route" - Manage Routing Table

"netstat" - Display Network Statistics

"lsof" - List of Open Files

Internet Networking Tools

"wget" - Get Files from the Web

"cURL" - Client for URL

SSH Protocol and ssh/scp Commands

Administrative Tasks

"systemctl status/start/stop/enable/disable" Commands

"shutdown" and "halt/poweroff/reboot" Commands

Move /home Directory to New Partition

Move All Users to a New System

"last/lastb" - Review Login History

References

Full Version in PDF/EPUB

Keywords: Ubuntu, Linux, Tutorials