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

The AAA framework

The access control framework is often referred to as AAA due to its three components: authentication, authorization, and accounting.

Authentication is responsible for verifying the user’s identity – usually by checking whether the user possesses certain knowledge (such as a password), data (such as a cryptographic key or the correct seed for a time-based authentication algorithm), a physical item (such as a hardware key storage), or an attribute (such as a fingerprint).

Authorization is the process of checking whether the user that attempts to execute an action has permission to do so. Since in UNIX systems many entities, such as hardware devices and sockets, are represented as files, a lot of the time, file access permissions are used as an authorization framework.

Finally, the accounting process ensures that user actions are recorded so that it is possible to attribute actions to users, monitor user activity for anomalies, and investigate...