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

Pluggable Authentication Modules

NSS helps programs retrieve various information, including usernames, group membership information, and password hashes. However, the logic for authentication still has to exist somewhere. For example, to conduct password-based authentication, there must be code that calculates a hash sum from a plain text password that the user enters and checks it against the hash stored in an authentication database.

However, there is more to authentication policies than just having passwords and checking that they are correct. Administrators may want to enforce password-strength rules or use multi-factor authentication to increase security, for example. Authentication using remote databases also presents challenges, such as credential caching to ensure that users are not locked out of their machines when the remote database becomes temporarily unavailable.

To allow developers and administrators to create and set up tools for flexible authentication policies...