Introduction to Linux: Major Distribution Families and Installation

This course focuses on the three major Linux distribution families: Red Hat, SUSE, and Debian, and provides in-depth knowledge about their components and configurations.

### Introduction to Linux: Distribution Families and Installation
* 🐧 This course, taught by Beau Carnes, introduces Linux to users with limited or no previous exposure, covering **tools and techniques commonly used by Linux system administrators and end users**.
* 📚 The course focuses on the three major Linux distribution families: **Red Hat (including RHEL, CentOS, Fedora)**, **SUSE (including SLES, openSUSE)**, and **Debian (including Ubuntu, Linux Mint)**.
* 📊 Red Hat's family includes CentOS Stream as a replacement for CentOS 8, while Fedora serves as an **upstream testing platform** for RHEL. SUSE's family includes SLES (upstream) and openSUSE, with both using the **RPM-based zypper package manager**.
* 🔑 Debian serves as the upstream for Ubuntu, which in turn is upstream for Linux Mint. Ubuntu aims to **balance long-term stability and ease of use**, with **access to a large software repository**.
* 🖥 The course emphasizes the importance of having a **Linux distribution installed** to follow along, recommending a **native installation or use of a virtual machine** for learning purposes.
* 📜 Common Linux terms are introduced, including **kernel**, **distribution**, **bootloader**, **service**, **file system**, **X Windows system**, **desktop environment**, and **command line**.
* 🛠 The installation process for Ubuntu and CentOS is demonstrated, highlighting the **ease of installation** and **default choices** made by modern Linux installers.
* 📋 Considerations for choosing a distribution include **system function, package requirements, disk space, update frequency, support cycle, hardware compatibility, and stability requirements**.

### Setting Up and Configuring Linux GUI Environments (CentOS 8, openSUSE, and GNOME)
* 🖥 The text provides a step-by-step guide on setting up and configuring Linux graphical user interfaces (GUIs) on **CentOS 8, openSUSE, and GNOME desktop environments**.
* 🔧 Initial Setup: The installation process is detailed, including **user account creation, password setup, and system configuration** during installation.
* 🐧 CentOS 8 Installation: The text demonstrates the installation of CentOS 8, including **partition setup**, **time zone selection**, **desktop environment choice (GNOME)**, and **user account creation**.
* 🦎 openSUSE Installation: A similar installation process is shown for openSUSE Leap, with **partition setup, desktop environment selection (GNOME), and user account creation**.
* 🔒 Security and Passwords: The text highlights the importance of **strong passwords and secure configurations**, despite using **simple passwords for demonstration purposes**.
* 🖥 ️ GUI Management: Detailed instructions are provided for **managing GUI sessions**, **changing desktop backgrounds**, **setting default applications**, and **locking/unlocking screens**.
* 🖥 The text explains how to configure display settings, including **resolution adjustments**, **multi-monitor setups**, and **display layout changes**.
* 🕒 Date and Time Settings: The process for adjusting **date and time settings**, including **time zone selection** and **display format changes**, is demonstrated.
* 🌐 Network Configuration: The text covers network configuration using Network Manager, including **wired, wireless, mobile broadband, and VPN connections**.

### Linux System Administration: Basic Configuration and Command Line Operations
* 🖥 Linux provides a variety of tools for basic system configuration and network management, including **Network Manager** for wired and wireless connections, and package management systems like **dpkg and RPM**.
* 🔧 The graphical interface is available for package management on Ubuntu, using tools like **Gnome Software** and **Synaptic Package Manager**, and on openSUSE, using **YaST Software Manager**.
* 📦 Package management is crucial for installing and updating software on Linux, with Debian-based systems using **dpkg and apt**, and Red Hat-based systems using **RPM and YUM/DNF**.
* 🌐 Linux offers a wide range of internet applications, including web browsers, email clients, and multimedia tools, with popular options like **Firefox, Thunderbird, and VLC**.
* 📂 The command line is essential for system administration, with commands like **cd for navigation**, **ls for listing files**, and **touch for file timestamp management**.
* 🔗 Linux supports both **hard and symbolic links**, with **hard links sharing the same inode** and **symbolic links acting as pointers to other files**.
* 🔒 System security is managed through tools like **sudo**, which allows users to run programs with the security privileges of another user, typically the **root superuser**.
* 🖥 Linux systems can be managed both through the **graphical desktop environment** and **virtual terminals (VTs)**, with the ability to switch between them using **Ctrl + Alt + function key**.

### Linux Command Line Basics: File Operations, Redirection, and Package Management
* 📁 Basic file operations include creating, renaming, and removing files and directories using commands like **`echo`**, **`touch`**, **`mv`**, **`rm`**, and **`mkdir`**.
* 📄 Understanding file streams and file descriptors is crucial, as all open files are represented by numbers starting at zero, with **standard input (0), output (1), and error (2)**.
* 🔀 Redirection is a powerful feature in Linux, allowing users to **change where a command gets its input and where it writes its output**, using symbols like `<`, `>`, and `2>` for standard error.
* 🔄 The Unix/Linux philosophy emphasizes using many short programs that cooperate via pipes (`|`) to accomplish **complex tasks efficiently**, without **saving temporary files between stages**.
* 🔍 The `locate` and `find` utilities are essential for searching files on a Linux system, with `locate` using a **pre-built database** and `find` allowing **more complex searches and actions**.
* 📦 Package management is critical for **installing, removing, and updating software**, with Debian-based systems using **`apt`**, Red Hat-based systems using **`dnf`**, and openSUSE systems using **`zypper`**.
* 📖 Documentation sources like `man` pages and `info` provide detailed information on commands and topics, with **`man` being the most commonly used source for Linux documentation**.
* 📚 The `info` system is an alternative to `man` pages, providing **freeform documentation with linked subsections** and support for **browsing through topics**.

### Linux Documentation: A Comprehensive Guide
* 📚 Linux documentation is essential for understanding system functions, with key sources including **Man pages**, the **new info system**, and the **help command**.
* 📖 Man pages provide detailed information on programs, system calls, and kernel functions, with the **'man' command** used to **access them**.
* The new info system, created by the GNU project, offers **robust documentation** accessible via **command line, web, and graphical tools**.
* 🔍 The '**help**' command provides quick access to **short descriptions of commands**, similar to '-h' or '--help' options for standalone programs.
* 📈 The '**PS**' command is used to display information about currently running processes, with various options available for **customization**.
* 📊 The '**top**' command provides real-time updates on system performance, including CPU and memory usage, and allows for **interactive process management**.
* ⏰ Scheduling tasks is achieved using the '**at**' command for one-time jobs and '**cron**' for recurring tasks, with '**sleep**' used for delaying execution.
* 📂 Understanding the file system hierarchy is crucial, with key directories like **'/bin', '/etc', '/proc', and '/var'** playing important roles in system operation.

### Linux File System and Text Manipulation
* 📁 The Linux file system tree starts at the root directory, often referred to as **`/` or "trunk"**.
* 📝 The Filesystem Hierarchy Standard (FHS) provides a **standard directory structure** for Linux systems.
* 🔒 Partitions help segregate files based on **usage, ownership, and type**.
* 🔗 File systems can be mounted at **any location** on the main file system tree.
* 🖥 Pseudo file systems like `/proc` exist **only in memory**.
* 🔐 Understanding file extensions in Linux: "File extensions do not necessarily determine the **type of file**."
* 📦 Basic file manipulation commands: `**cp**` for copying files, `**rsync**` for efficient synchronization.
* 📂 Backup methods: "Rsync is more efficient than `cp` for **synchronizing entire directory trees**."
* 📝 Patching: "Patch files contain the **deltas or changes** needed to update an old file version to a new one."

### Mastering Basic Linux Operations: Files, Text Manipulation, and Networking
* 📁 **File Manipulation**: Learn to create, view, and combine text files using `cat`, `nano`, and `sed`. Understand how to manage large files using `less`, `head`, and `tail`. Explore advanced text manipulation with `awk` and file sorting with `sort`.
* 🔍 Regular Expressions: Discover the power of **regular expressions** for **pattern matching** in text files using utilities like `grep` and `strings`.
* 🌐 **Networking Basics**: Understand the fundamentals of networking, including **IP addressing, classes, and protocols**. Learn to **configure and manage network interfaces** using tools like `ifconfig`, `ip`, and `ping`.
* 🔒 **Secure Communication**: Explore secure communication with `SSH` for remote access and `SCP` for secure file transfer between systems.
* 🌐 Internet Access: Learn to browse the web using both graphical (Firefox, Chrome) and non-graphical (links, w3m) browsers. Master file downloads with **`wget`** and URL inspections with **`curl`**.
* 📊 Summary of Key Concepts: Review essential networking and file manipulation tools, including **`tr`, `tee`, `wc`, and `cut`**. Understand the basics of **DNS and IP routing** for network communication.

Introduction to Linux – Full Course for Beginners

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Introduction to Linux: Key Concepts and Major Distribution Families

Beau Carnes introduces a course for Linux beginners, covering tools and techniques for system administration and end users.

The course focuses on the three major Linux distribution families: Red Hat, SUSE, and Debian, exploring their representative members.

Linux distributions provide a complete system with the kernel and other software tools for file operations, user management, and package management.

Major commercial distributions from Red Hat, SUSE, and Canonical are preferred by large organizations, while CentOS and CentOS Stream are popular free alternatives.

Ubuntu and Fedora are widely used by developers and in the educational realm, and Scientific Linux is favored by the scientific research community.

The Boot Process in x86-based Linux Systems

The boot process starts with the BIOS initializing hardware and performing the POST.

Then, the control moves to the bootloader, which loads the kernel image and initial RAM disk into memory.

The kernel initializes hardware, mounts the root file system, and starts the init process to get the system running.

Linux file systems have a standard layout and are organized according to the Filesystem Hierarchy Standard.

The choice of Linux distribution depends on factors such as system function, package requirements, hardware, support cycle, and partition layout.

The installation process for Linux distributions is similar, involving setting up security features, choosing software packages, and configuring the system.

Some distributions also support installation over the network using mini installers and configuration files.

Step-by-Step Installation of Ubuntu and CentOS

An automatic installation file is provided for Linux installation, followed by the actual installation process.

The installation may include additional questions and the option to download updates.

The process involves creating a new virtual machine, customizing hardware, allocating space, and choosing the installation type.

The installation also requires setting up the network, configuring the time and date, selecting the software, and performing the partitioning setup, including choosing the file system and mount points.

The installation of Ubuntu is straightforward, with the system making most of the decisions, while the CentOS installation involves choosing default options and customizing the partitioning.

The installations also require setting up root account password and creating a user.

Installing CentOS 8 and openSUSE on a Virtual Machine

The installation of CentOS 8 involves choosing a simple password for the student user, waiting for the installation to complete, and then rebooting the system.

On the other hand, the installation of openSUSE includes accepting the license agreement, customizing partition settings, choosing the desktop environment, and setting up the user and root passwords before waiting for the installation to finish and rebooting the system.

The key concepts covered in the chapter include the partitioning of the disk, the boot process, and the management of graphical interface sessions in Linux.

The openSUSE installation process also involves choosing the time zone, selecting the desktop environment, and setting up user accounts, while the CentOS 8 installation process includes configuring the kernel, installing the bootloader, and generating the init Ram FS file system.

Managing User Sessions and System Settings in Linux

Logging in and out of a Linux system is a simple process of selecting the user and using the upper right corner menu to log out or switch users.

Changing the desktop background and theme can be done by right-clicking on the background and selecting the desired options.

Gnome Tweaks is a useful tool for exposing more setting options and installing extensions.

Switching users on Ubuntu involves selecting the user from the upper right corner and choosing to log in, log out, or switch users.

Restarting or shutting down the system is easily done by clicking on the power or gear icon and selecting the desired action.

Locking and unlocking the screen on a GNOME distribution can be done by clicking on the upper right corner and using the lock button, or by using a combination of keys, such as the Super Key plus L.

Managing user accounts and passwords allows for individualized settings and home directories for each user.

Setting default applications on a Red Hat system involves going to

Navigating the Linux File Manager and Gnome Desktop

The file manager in Linux, such as Nautilus, allows users to access different locations on the computer and the network, including the home directory and other commonly used folders.

It provides various ways to view and customize the display of files and directories, as well as a search tool for easy file location.

Deleting files can be done by moving them to the trash directory, with options for permanent deletion.

The Gnome desktop environment offers a range of configuration options for display, date and time settings, and network management, which can be accessed through the system settings panel, providing users with a high level of customization and control.

Managing Network Connections and Software Packages in Linux

Manual setup for static configurations can be easily done through Network Manager, including changing the Ethernet MAC address and managing wireless networks.

Network Manager can also handle mobile broadband and VPN connections.

The DPKG packaging system is used for Debian family systems, while the RPM packaging system is used by Red Hat and SUSE family systems for software management.

Graphical interfaces like GNOME Software and Synaptic Package Manager provide easy ways to install, upgrade, and remove software packages in Linux distributions like Ubuntu.

Linux uses Coordinated Universal Time (UTC) for internal timekeeping and allows setting the date and time from the system settings window.

The network time protocol is the primary method for setting the local time via internet servers.

Linux offers a wide range of internet applications, including web browsers, email clients, and online media tools, and provides various development applications and tools.

The command-line interface in Linux provides numerous advantages, and terminal emulator programs, such as GNOME terminal, are commonly used to emulate a text mode terminal in a window.

Setting up sudo, the command that allows users to run programs with the security privileges of another user, typically the superuser, is essential in Linux systems.

Using Virtual Terminal Sessions (VTS) can help troubleshoot problems with the graphical desktop by switching to a text VTS.

The shutdown command is the preferred method for shutting down or rebooting the system, and it requires super user or root access.

Navigating the file system can be done using absolute or relative paths, with the tree command providing an overview of the file system tree.

Hard links and symbolic links are useful for linking files and directories, with symbolic links being able to point to objects on different file systems.

The CD command, along with pushd and popd, helps in navigating directories, while various commands like cat, less, head, tail, and touch are used for viewing and managing files.

Directories can be created with mkdir and removed with rmdir or rm -rf, and the MV command is used for renaming and moving files.

The "RM -RF" command is used to remove a whole file system tree and should be used with caution, especially when used by the root user.

The "PS1" variable in Linux is used to customize the command line prompt and can be set to display various information, such as the user and host system name.

In Linux, file streams are represented by file descriptors, with standard input as file descriptor 0, standard output as file descriptor 1, and standard error as file descriptor 2.

The use of pipes in Linux allows for the combination of multiple commands, increasing efficiency by utilizing available computing power and saving disk space.

The "locate" and "find" commands, along with wildcards, are commonly used for searching and locating files in Linux, with the "locate" command utilizing a pre-constructed database and the "find" command providing more detailed search options.

Using Wildcards in Linux and Package Management

Using quotes with wildcards in Linux allows for more accurate and specific search results.

The find command in Linux is used to locate files based on various conditions and can also execute commands on the search results.

Package management systems like apt and dnf are essential for installing, removing, and searching for packages in Linux, with high-level tools handling dependency resolution.

The find command in Linux is a powerful tool for searching and executing commands on files based on specific criteria, such as name, type, and size.

Using quotes with wildcards in Linux allows for more accurate and specific search results, and the find command can also execute commands on the search results.

Package management systems like apt and dnf are crucial for handling the installation and removal of packages in Linux, with high-level tools taking care of dependency resolution and management.

Virtual terminals in Linux use the connected monitor and keyboard, while the terminal emulator program works within a window on the graphical desktop.

The system allows logging in via text terminal or remotely via the console, with the preferred method of shutting down or rebooting the system using the shutdown command.

There are two types of path names: absolute and relative, and Linux provides the use of hard and soft symbolic links.

By using the APT packaging tool for Debian-based systems and the DNF command-line utility for RPM-based Red Hat Family Linux distributions, users can effectively manage installed software.

The zipper package management system, based on RPM and used for openSUSE, is also a crucial tool for package management.

Linux Documentation Sources and Basic Commands

The main sources of Linux documentation are the Man pages, new info, and the help options and commands, along with a variety of online sources.

The Man pages offer detailed information about programs, system calls, and more.

The new info system, an alternative to Man, provides freeform documentation with linked subsections.

The -h or --help argument and the help command offer short descriptions for commands, while also built-in commands can be viewed with the help option.

Managing Process Priority and System Performance in Linux

Processes' priority in Linux can be manipulated using commands like "ps" and "nice" to change the niceness value, affecting the process's priority.

The load average, which indicates system workload, can be monitored using commands like "top," with a load average of 1.

00 per CPU signaling a fully subscribed system.

Monitoring system performance in real-time and managing process priority is crucial for maintaining a stable and efficient Linux system, especially in terms of CPU and memory usage.

The "top" utility provides real-time monitoring of processes and system performance, allowing users to interactively view and manage running tasks.

The "at" utility is used to execute non-interactive commands at a specific time, while "cron" is a time-based scheduling tool for routine jobs.

Linux uses a hierarchical file system, with native and legacy file system types supported.

GParted is a utility used for displaying and managing the partition layout on a system.

The "mount" command is used to attach a file system to the file system tree, and the "unmount" command is used to detach it.

Network file systems like NFS and CIFS/Samba are used to share data across physical systems, allowing access to the same files and resources from multiple client systems.

These systems play a crucial role in providing shared access to files and configuration across a network.

The Linux file system uses a hierarchical structure and allows for partitioning and mounting of file systems.

Pseudo file systems like /proc exist only in memory and contain virtual files for viewing kernel data.