Mastering Linux Administration

Alexandru Calcatinge, Julian Balog

• Publisher: Packt Publishing
• Year: 2021
• ISBN:
  9781789953602
• Edition: 1
• Topic: Informatique
• Subtopic: Administration du système

Develop advanced skills for working with Linux systems on-premises and in the cloudKey Features• Become proficient in everyday Linux administration tasks by mastering the Linux command line and using automation• Work with the Linux filesystem, packages, users, processes, and daemons• Deploy Linux to the cloud with AWS, Azure, and KubernetesBook DescriptionLinux plays a significant role in modern data center management and provides great versatility in deploying and managing your workloads on-premises and in the cloud. This book covers the important topics you need to know about for your everyday Linux administration tasks. The book starts by helping you understand the Linux command line and how to work with files, packages, and filesystems. You'll then begin administering network services and hardening security, and learn about cloud computing, containers, and orchestration. Once you've learned how to work with the command line, you'll explore the essential Linux commands for managing users, processes, and daemons and discover how to secure your Linux environment using application security frameworks and firewall managers. As you advance through the chapters, you'll work with containers, hypervisors, virtual machines, Ansible, and Kubernetes. You'll also learn how to deploy Linux to the cloud using AWS and Azure. By the end of this Linux book, you'll be well-versed with Linux and have mastered everyday administrative tasks using workflows spanning from on-premises to the cloud. If you also find yourself adopting DevOps practices in the process, we'll consider our mission accomplished.What you will learn• Understand how Linux works and learn basic to advanced Linux administration skills• Explore the most widely used commands for managing the Linux filesystem, network, security, and more• Get to grips with different networking and messaging protocols• Find out how Linux security works and how to configure SELinux, AppArmor, and Linux iptables• Work with virtual machines and containers and understand container orchestration with Kubernetes• Work with containerized workflows using Docker and Kubernetes• Automate your configuration management workloads with AnsibleWho this book is forIf you are a Linux administrator who wants to understand the fundamentals and as well as modern concepts of Linux system administration, this book is for you. Windows System Administrators looking to extend their knowledge to the Linux OS will also benefit from this book.

Section 1: Linux Basic Administration

In this first section, you will master the Linux command line and basic administrative tasks such as managing users, packages, files, services, processes, signals, and disks.

This part of the book comprises the following chapters:

• Chapter 1, Installing Linux
• Chapter 2, The Linux Filesystem
• Chapter 3, Linux Software Management
• Chapter 4, Managing Users and Groups
• Chapter 5, Working with Processes, Daemons, and Signals

Chapter 1: Installing Linux

The recent years have marked a significant rise in the adoption of Linux as the operating system of choice for both server and desktop computing platforms. From enterprise-grade servers and large-scale cloud infrastructures to individual workstations and small-factor home appliances, Linux has become an ever-present platform for a wide range of applications.

The prevalence of Linux, perhaps now more than ever, brings into the spotlight much-needed administration skills for a growing community of system administrators and developers. In this book, we take a practical approach to Linux administration essentials, with the modern-day system administrator, DevOps, or developer in mind.

In this first chapter, we'll guide you through the Linux installation process, either on physical hardware (bare metal) or using a Virtual Machine (VM). We'll take you further with a few case studies on choosing a Linux distribution based on functional requirements. Along the way, we introduce you to the Linux graphical user interface with some hands-on examples of configuring GNOME and KDE. Finally, we build a Linux workstation suitable for our daily computing needs.

Here are the topics we cover in this chapter:

• The Linux operating system
• Linux distributions
• Choosing the right Linux distribution
• Installing Linux - the basics
• The Windows Subsystem for Linux (WSL)
• Installing Linux graphical user interfaces
• Setting up and using the Linux workstation

Technical requirements

We will use the following platforms and technologies in this chapter:

• Linux distributions: Ubuntu Server, Ubuntu Desktop, CentOS
• Linux package managers: DEB, RPM
• VM hypervisors: Oracle VM VirtualBox, VMware Workstation
• VM host platforms: Windows, macOS X
• The Bash Command-Line Interface (CLI)
• GitHub (https://github.com/)

The Linux operating system

Linux is a relatively modern operating system created in 1991 by Linus Torvalds, a Finnish computer science student at the time, from Helsinki. Originally released as a free and open source platform prohibiting commercial redistribution, Linux eventually adopted the GNU General Public Licensing (GPL) model in 1992. This move played a significant role in its wide adoption by the developer community and commercial enterprises alike.

It is important to note that the Free Software Foundation community distinctly refers to Linux operating systems (or distributions) as GNU/Linux to emphasize the importance of GNU or free software.

Initially made for Intel x86 processor-based computer architectures, Linux has since been ported to a wide variety of platforms, becoming one of the most popular operating systems currently in use.

The genesis of Linux might be considered the open source alternative of its mighty predecessor, Unix. This system was a commercial-grade operating system developed at AT&T Bell Labs research center by Ken Thompson and Dennis Ritchie in 1969.

Linux distributions

A Linux operating system is typically referred to as a distribution. A Linux distribution, or distro, is the installation bundle (usually an ISO image) of an operating system that has a collection of tools, libraries, and additional software packages installed on top of the Linux kernel.

A kernel is the core interface between a computer's hardware and its processes, controlling the communication between the two and managing the underlying resources as efficiently as possible.

The software collection bundled with the Linux kernel usually consists of a bootloader, shell, package management system, graphical user interface, and various software utilities and applications.

The following diagram is a simplified illustration of a generic Linux distribution architecture:

Figure 1.1 – Simplified view of a generic Linux architecture

There are hundreds of Linux distributions currently available. Among the most popular are Debian, Fedora, openSUSE, Arch Linux, and Slackware, with many other Linux distributions either based upon or derived from them. Some of these distros are divided into commercial and community-supported platforms.

One of the key differences between Linux distributions is the package management system they use and the related Linux package format. We'll get into more detail on this topic in later chapters. For now, the focus is on choosing the right Linux distribution ...