Book Image

Linux for System Administrators

By : Viorel Rudareanu, Daniil Baturin
Book Image

Linux for System Administrators

By: Viorel Rudareanu, Daniil Baturin

Overview of this book

Linux system administration is an essential aspect of maintaining and managing Linux servers within an organization. The role of a Linux system administrator is pivotal in ensuring the smooth functioning and security of these servers, making it a critical job function for any company that relies on Linux infrastructure. This book is a comprehensive guide designed to help you build a solid foundation in Linux system administration. It takes you from the fundamentals of Linux to more advanced topics, encompassing key areas such as Linux system installation, managing user accounts and filesystems, networking fundamentals, and Linux security techniques. Additionally, the book delves into the automation of applications and infrastructure using Chef, enabling you to streamline and optimize your operations. For both newcomers getting started with Linux and professionals looking to enhance their skills, this book is an invaluable hands-on guide with a structured approach and concise explanations that make it an effective resource for quickly acquiring and reinforcing Linux system administration skills. With the help of this Linux book, you’ll be able to navigate the world of Linux administration confidently to meet the demands of your role.
Table of Contents (21 chapters)
Part 1: Linux Basics
Part 2: Configuring and Modifying Linux Systems
Part 3: Linux as a Part of a Larger System

Executables versus processes

Programs are distributed as executable files. In many historical operating systems, programs would be loaded from files directly into memory byte by byte. That approach was certainly simple to implement, but it has many limitations (most notably, the requirement to have a fixed memory layout and the inability to store any metadata), so later systems invented special formats for executable files.

For example, if we inspect the Bourne Again Shell (Bash) executable with the file command, we’ll see something like this:

$ file /bin/bash
/bin/bash: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/, BuildID[sha1]=9c4cb71fe5926100833643a8dd221ffb879477a5, for GNU/Linux 3.2.0, stripped

If you use a Linux distribution other than Debian or Red Hat derivatives (which are the main focus of this book) and the preceding command fails for you, you can find the location of the bash executable...