Book Image

Mastering Linux Security and Hardening - Second Edition

By : Donald A. Tevault
Book Image

Mastering Linux Security and Hardening - Second Edition

By: Donald A. Tevault

Overview of this book

From creating networks and servers to automating the entire working environment, Linux has been extremely popular with system administrators for the last couple of decades. However, security has always been a major concern. With limited resources available in the Linux security domain, this book will be an invaluable guide in helping you get your Linux systems properly secured. Complete with in-depth explanations of essential concepts, practical examples, and self-assessment questions, this book begins by helping you set up a practice lab environment and takes you through the core functionalities of securing Linux. You'll practice various Linux hardening techniques and advance to setting up a locked-down Linux server. As you progress, you will also learn how to create user accounts with appropriate privilege levels, protect sensitive data by setting permissions and encryption, and configure a firewall. The book will help you set up mandatory access control, system auditing, security profiles, and kernel hardening, and finally cover best practices and troubleshooting techniques to secure your Linux environment efficiently. By the end of this Linux security book, you will be able to confidently set up a Linux server that will be much harder for malicious actors to compromise.
Table of Contents (20 chapters)
1
Section 1: Setting up a Secure Linux System
8
Section 2: Mastering File and Directory Access Control (DAC)
11
Section 3: Advanced System Hardening Techniques

Creating a user group and adding members to it

So far, I've been doing all of the demos inside my own home directory, just for the sake of showing the basic concepts. But the eventual goal is to show you how to use this knowledge to do something more practical, such as controlling file

Let's say that we want to create a marketing group for members of—you guessed it—the marketing department:

[donnie@localhost ~]$ sudo groupadd marketing
[sudo] password for donnie:
[donnie@localhost ~]$

Let's now add some members. You can do that in three different ways:

  • Add members as we create their user accounts.
  • Use usermod to add members that already have user accounts.
  • Edit the /etc/group file.

Adding members as we create their user accounts

...