Book Image

Mastering Linux Administration

By : Alexandru Calcatinge, Julian Balog
Book Image

Mastering Linux Administration

By: Alexandru Calcatinge, Julian Balog

Overview of this book

Linux 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.
Table of Contents (20 chapters)
Section 1: Linux Basic Administration
Section 2: Advanced Linux Server Administration
Section 3: Cloud Administration

Introducing the Linux shell

Linux has its roots in the Unix operating system, and one of its main strengths is the command-line interface. In the old days, this was called the shell. In Unix, the shell is invoked with the sh command. The shell is a program that has two streams: an input stream and an output stream. The input is a command given by the user, and the output is the result of that command, or an interpretation of it. In other words, the shell is the primary interface between the user and the machine.

The main shell in major Linux distributions is called Bash, which is an acronym for Bourne Again Shell, named after Steve Bourne, the original creator of the shell in Unix. Ubuntu, Fedora, CentOS, RHEL, Debian, and openSUSE all use Bash as their default shell. Alongside Bash, there are other shells available in Linux, such as ksh, tcsh, and zsh. In this chapter, we will cover the Bash shell, as it is the most widely used shell in modern Linux distributions.

One shell...