Book Image

Red Hat Enterprise Linux 8 Administration

By : Miguel Pérez Colino, Pablo Iranzo Gómez, Scott McCarty
Book Image

Red Hat Enterprise Linux 8 Administration

By: Miguel Pérez Colino, Pablo Iranzo Gómez, Scott McCarty

Overview of this book

Whether in infrastructure or development, as a DevOps or site reliability engineer, Linux skills are now more relevant than ever for any IT job, forming the foundation of understanding the most basic layer of your architecture. With Red Hat Enterprise Linux (RHEL) becoming the most popular choice for enterprises worldwide, achieving the Red Hat Certified System Administrator (RHCSA) certification will validate your Linux skills to install, configure, and troubleshoot applications and services on RHEL systems. Complete with easy-to-follow tutorial-style content, self-assessment questions, tips, best practices, and practical exercises with detailed solutions, this book covers essential RHEL commands, user and group management, software management, networking fundamentals, and much more. You'll start by learning how to create an RHEL 8 virtual machine and get to grips with essential Linux commands. You'll then understand how to manage users and groups on an RHEL 8 system, install software packages, and configure your network interfaces and firewall. As you advance, the book will help you explore disk partitioning, LVM configuration, Stratis volumes, disk compression with VDO, and container management with Podman, Buildah, and Skopeo. By the end of this book, you'll have covered everything included in the RHCSA EX200 certification and be able to use this book as a handy, on-the-job desktop reference guide. This book and its contents are solely the work of Miguel Pérez Colino, Pablo Iranzo Gómez, and Scott McCarty. The content does not reflect the views of their employer (Red Hat Inc.). This work has no connection to Red Hat, Inc. and is not endorsed or supported by Red Hat, Inc.
Table of Contents (25 chapters)
1
Section 1: Systems Administration – Software, User, Network, and Services Management
9
Section 2: Security with SSH, SELinux, a Firewall, and System Permissions
14
Section 3: Resource Administration – Storage, Boot Process, Tuning, and Containers
21
Section 4: Practical Exercises

Summary

Security is a very important part of system administration. Disabling the security measures on a system just because it's in an isolated network goes against the defense in depth principle, so this is heavily discouraged.

In this chapter, we saw how simple and easy it is to configure a firewall using firewalld, in RHEL8, thus providing us with another tool to manage, filter, and secure the network connections in our system. We also worked with cockpit, a web administration tool that makes this task more visual and easier to perform.

We can now take control of the network connectivity of our systems, provide access to the services we want to provide, and add a layer of security to them. We also know how to manage zones and how to use them, depending on our system's use case. We are now ready to define our own custom services so that we can always filter network connectivity for them. We can now also deploy more secure systems by using the firewall included...