Chapter 1: Getting Started with Red Hat Enterprise Linux PDF

CHAPTER 1: GETTING STARTED WITH RED HAT ENTERPRISE LINUX Hasnaa Sleiman Master in Telecommunications, Network and Security-UA- USJ-UL What is Linux? Definition: Linux is a Unix-like operating system kernel. Developed by Linus Torvalds in 1991. Purpose:...

CHAPTER 1: GETTING STARTED WITH RED HAT ENTERPRISE LINUX Hasnaa Sleiman Master in Telecommunications, Network and Security-UA- USJ-UL What is Linux? Definition: Linux is a Unix-like operating system kernel. Developed by Linus Torvalds in 1991. Purpose: Manages hardware resources. Provides a foundation for other software. Components: Kernel: Core component that manages hardware and system resources. User Space: Includes libraries, utilities, and applications. Linux Kernel Overview Role of Kernel: Process Scheduler: Manages execution of processes. Memory Manager: Handles allocation and deallocation of memory. Device Drivers: Interfaces with hardware devices. Kernel Types: Monolithic Kernel: All system services run in kernel space. Microkernel: Minimizes the kernel’s role, running services in user space. Linux Kernel Overview Web Browsing: Servers: Many web servers run on Linux (e.g., Apache, Nginx). Point-of-Sale Systems: Retail: Linux powers many point-of-sale systems. Cloud Computing: Platforms: AWS, Google Cloud, Azure use Linux. Supercomputers: Top 500 List: Most supercomputers run on Linux due to scalability and flexibility. Why Learn Linux? Interoperability: Cross-Platform Skills: Essential for working with mixed-OS environments. Application Hosting: Servers: Linux is a popular choice for hosting applications and services. Cloud and IoT: Prevalence: Many IoT devices and cloud services run Linux. Career Opportunities: Demand: Linux skills are highly sought after in the IT job market What Makes Linux Great? Open Source: Visibility: Source code is accessible and modifiable. Community Contributions: Improvements are made by a global community. Command-Line Interface (CLI): Scripting: Powerful for automation and scripting tasks. Administration: Allows efficient local and remote system management. Modular System: Customization: Users can tailor the system by adding or removing components What is Open Source Software? Definition: Source Code: Available for use, study, modification, and distribution. Source Code: Human-Readable Instructions: Instructions written in programming languages. Licenses: Control: Governs how software can be used and shared. Open Source vs. Proprietary Software Open Source: Access: Source code is available. Freedom: Users can modify and distribute the software. Proprietary Software: Restricted: Source code is not available. Usage: Typically limited to running the software as-is. Benefits of Open Source Software Control: Customization: Modify code to suit specific needs. Training: Learning Opportunity: Study real-world code for educational purposes. Security: Transparency: Inspect and fix code vulnerabilities. Stability:Long-Term Use: Code can continue to be used and improved even if the original developers are not available. Types of Open Source Licenses Copyleft Licenses: Purpose: Ensure that derivative works remain open source. Examples: GNU GPL, LGPL. Permissive Licenses: Purpose: Allow code reuse in both open and proprietary software. Examples: MIT License, BSD License, Apache License 2.0. Copyleft Licenses Definition: Share-Alike Requirement: Derivative works must be distributed under the same license. Examples: GNU General Public License (GPL): Requires derivative works to also be open source. Lesser GNU Public License (LGPL): Similar to GPL but more permissive for linking with proprietary code Permissive Licenses Definition: Flexibility: Allows integration with proprietary software. Examples: MIT License: Allows code to be used with few restrictions. BSD License: Includes clauses for code reuse with attribution. Apache License 2.0: Provides an explicit grant of patent rights Who Develops Open Source Software? Professional Developers: Organizational Support: Many are employed to work on open source projects. Volunteers: Community Contributions: Contribute in their free time. Academic Community: Research and Development: Contributes to advancing technology and innovation. The Role of Red Hat Overview: Leading Provider: Specializes in open source software solutions. Mission: Community-Driven: Catalyze technology development through community involvement. Key Areas: Linux: Red Hat Enterprise Linux. Middleware: JBoss. Virtualization: OpenShift. Cloud Technologies: OpenStack, Ceph. What is a Linux Distribution? Definition: Combination: Linux kernel plus a collection of user-space programs. Components: Kernel: Core of the operating system. Utilities and Libraries: Additional software and tools. Purpose: Ease of Use: Provides a ready-to-use system with pre- configured components Linux Distribution Characteristics Kernel and User Space Programs: Kernel: Manages hardware and resources. User Space: Contains applications and libraries. Variety: General-Purpose: Versatile distributions for various needs. Specialized: Distributions for specific purposes (e.g., security, multimedia). Installation and Updates: Package Managers: Tools to install and update software History of Linux Distributions Early Distributions: Slackware: One of the oldest distributions. Debian: Known for stability and extensive package repository. Evolution: Modern Distributions: CentOS, Fedora, Ubuntu, etc. Focus: Address different user needs from desktop to server environments. Introduction to Fedora Overview: Community-Driven: Sponsored by Red Hat. Focus: Innovation: Integrates the latest software and technologies. Support: Release Cycle: New releases every six months. Short-Term Support: Typically supports each release for about one year Fedora Features Support: CentOS: Self-support only, community-based. RHEL: Multiple support options including 24x7 support. Updates: CentOS: Matches RHEL’s errata. Introduction to Red Hat Enterprise Linux (RHEL) Overview: Enterprise-Ready: Focuses on stability and long-term support. Support Model: Subscription-Based: Provides access to support, updates, and resources. Features: Testing: Extensively tested for enterprise use. Certifications: Certified with various hardware and software vendors. RHEL Development Process Open Source Contributions: Collaboration: Contributes to and enhances open source projects. Fedora Integration: Testing Ground: Uses Fedora to integrate new technologies. Stabilization: Long-Term Support: Ensures software stability and reliability for enterprise use. RHEL vs. Fedora Fedora: Focus: Innovation and rapid updates. Support: Short-term (about one year). RHEL: Focus: Stability and enterprise readiness. Support: Long-term (several years), with extended support options. What is CentOS? Overview: Community-Driven: Derived from RHEL’s source code. Characteristics: Free: No cost for the distribution. Community Support: Maintained by volunteers and community contributors. CentOS vs. RHEL Support: CentOS: Self-support only, community-based. RHEL: Multiple support options including 24x7 support. Updates: CentOS: Matches RHEL’s errata.  Errata refers to a list of errors and their corrections or updates for a document, software, or system. In the context of software, particularly with operating systems like Red Hat Enterprise Linux (RHEL) and CentOS, errata are important updates that address various issues including: Bug Fixes: Corrections for issues or defects found in the software. Security Updates: Patches for vulnerabilities that could be exploited by attackers. Enhancements: Improvements to existing features or functionality. Documentation Updates: Corrections or updates to manuals and guides. Purpose of Errata Maintain System Security: Ensure that known vulnerabilities are patched to prevent security breaches. Improve Stability: Fix bugs that could affect system performance or functionality. Enhance Usability: Address issues that impact user experience and system usability. Types of Errata Security Errata: Updates related to vulnerabilities and security issues. Bug Fix Errata: Corrections for defects or bugs that impact system behavior. Enhancement Errata: Improvements or additions to existing features. Summary: What is Linux? Linux is a versatile operating system used in various applications, from web browsing and point-of-sale systems to supercomputers and cloud technologies. Importance: Learning Linux is crucial for IT professionals due to its widespread use in data centers, cloud computing, and more. Key Features of Linux: Open Source: Users can view, modify, and distribute the source code. This fosters rapid innovation and collaboration. Command-Line Interface (CLI): Provides powerful automation and administration capabilities. Modularity: Allows easy replacement or removal of system components. What is Open Source Software? Open Source: Software with accessible source code that can be modified and shared. Promotes collaboration and transparency. Proprietary Software: Closed source software where users can only run the program without access to the code. Types of Open Source Licenses: Copyleft Licenses: Require derived works to also be open source (e.g., GNU GPL). Permissive Licenses: Allow code to be used in proprietary software as long as the original license terms are preserved (e.g., MIT License). Who Develops Open Source Software? Open source development involves both professional developers and volunteers. Many organizations support and contribute to open source projects. Who is Red Hat? Red Hat: A leading provider of open source solutions, known for its Linux distribution, Red Hat Enterprise Linux (RHEL). Role: Connects customers with open source communities, provides support, and integrates open source projects into commercial products. What is a Linux Distribution? Definition: An installable operating system consisting of the Linux kernel and various user programs and libraries. Components: Includes the Linux kernel and supporting software, with different distributions tailored for various needs. Red Hat Enterprise Linux (RHEL): Development: Red Hat integrates open source software into RHEL through a multistage process involving Fedora and community collaboration. Fedora: A community-driven project that serves as a testing ground for new features before they are incorporated into RHEL. RHEL: A commercially supported, stable distribution designed for enterprise environments, offering extensive support and maintenance. CentOS vs. RHEL: CentOS: A free, community-supported distribution derived from RHEL’s source code. Lacks official support and has a different update and certification process compared to RHEL. Trying Out Red Hat Enterprise Linux: Evaluation: Available for download from Red Hat’s website for trial purposes. Developer Program: Offers free subscriptions for development and testing. Cloud Deployment: RHEL instances are available through cloud providers like AWS. QUIZ TIME Choose the correct answers to the following questions:  Which two of the following are benefits of open source software for the user? (Choose two.) a. Code can survive the loss of the original developer or distributor. b. Sensitive portions of code are protected and only available to the original developer. c. You can learn from real-world code and develop more effective applications. d. Code remains open as long as it is in a public repository but the license may change when included with closed source software.  Which two of the following are ways in which Red Hat develops their products for the future and interacts with the community? (Choose two.) a. Sponsor and integrate open source projects into the community-driven Fedora project. b. Develop specific integration tools only available in Red Hat distributions. c. Participate in upstream projects. d. Repackage and re-license community products.  Which two statements describe the benefits of Linux? (Choose two.) a. Linux is developed entirely by volunteers making it a low cost operating system. b. Linux is modular and can be configured as a full graphical desktop or a small appliance. c. Linux is locked in a known state for a minimum of one year for each release, making it easier to develop custom software. d. Linux includes a powerful and scriptable command- line interface, enabling easier automation and provisioning