Red Hat Enterprise Linux 8 Essentials

Neil Smyth

• Publisher: Packt Publishing
• Year: 2019
• ISBN:
  9781951442040
• Edition: 1
• Topic: Computer Science
• Subtopic: Operating Systems
• Index: Computer Science

Master the basics of the most widely used enterprise level operating systemsKey Features• Review the Red Hat Enterprise 8 Linux environment• Install and administer Red Hat Enterprise Linux 8• Share RHEL 8 files with remote systemsBook DescriptionRed Hat Enterprise Linux 8 is one of the most secure and dependable operating systems available. For this reason, the ambitious system or network engineer will find a working knowledge of Red Hat Enterprise 8 to be an invaluable advantage in their respective fields.This book, now updated for RHEL 8.1, begins with a history of Red Enterprise Linux and its installation. You will be virtually perform remote system administration tasks with cockpit web interface and write shell scripts to maintain server-based systems without desktop installation. Then, you will set up a firewall system using a secure shell and enable remote access to Gnome desktop environment with virtual network computing (VNC). You'll share files between the Red Hat Enterprise Linux 8 (RHEL 8) and Windows System using Samba client and NFS. You will also run multiple guest operating systems using virtualization and Linux containers, and host websites using RHEL 8 by installing an Apache web server. Finally, you will create logical disks using logical volume management and implement swap space to maintain the performance of a RHEL 8 system.By the end of this book, you will be armed with the skills and knowledge to install the RHEL 8 operating system and use it expertly.What you will learn• Install Gnome desktop environment to manage multiple workspaces• Access multiple servers simultaneously using cockpit web interface• Manage network configuration using NetworkManager• Configure firewall rules using firewall commands• Use Virsh tool to manage kernel-based virtual machine• Manage disk space by logical volume management and swap spaceWho This Book Is ForRed Hat Enterprise Linux 8 Essentials is for network engineers and system administrators who are new to the Red Hat Linux environment. Some working knowledge of Linux commands is recommended

1. Introduction

Arguably one of the most highly regarded and widely used enterprise level operating systems available today is the Red Hat Enterprise Linux (typically shortened to RHEL and pronounced rell) distribution. Not only is it considered to be among the most stable and reliable operating systems, it is also backed by the considerable resources and technical skills of Red Hat, Inc.

RHEL 8 Essentials is designed to provide detailed information on the installation, use and administration of the Red Hat Enterprise Linux 8 distribution. For beginners, the book covers topics such as operating system installation, the basics of the GNOME desktop environment, configuring email and web servers and installing packages and system updates using App Streams. Additional installation topics such as dual booting with Microsoft Windows are also covered, together with all important security topics such as configuring a firewall and user and group administration.

For the experienced user, topics such as remote desktop access, the Cockpit web interface, logical volume management (LVM), disk partitioning, swap management, KVM virtualization, Secure Shell (SSH), Linux Containers and file sharing using both Samba and NFS are covered in detail to provide a thorough overview of this enterprise class operating system.

1.1 Superuser Conventions

RHEL 8, in common with Linux in general, has two types of user account, one being a standard user account with restricted access to many of the administrative files and features of the operating system, and the other a superuser (root) account with elevated privileges. Typically, a user can gain root access either by logging in as the root user, or using the su - command and entering the root password. In the following example, a user is gaining root access via the su - command:

[neil@rhel8-demo ~]$ su -

Password:

[root@rhel8-demo ~]#

Note that the command prompt for a regular user ends with a $ sign while the root user has a # character. When working with the command-line, this is a useful indication as to whether or not you are currently issuing commands as the root user.

Alternatively, a single command requiring root privileges may be executed by a non-root user via the sudo command. Consider the following attempt to update the operating system with the latest patches and packages:

[neil@rhel8-demo ~]$ dnf update

Not root, Subscription Management repositories not updated

Error: This command has to be run under the root user.

Optionally, user accounts may be configured so that they have access to root level privileges. Instead of using the su - command to first gain root access, user accounts with administration privileges are able to run otherwise restricted commands using sudo.

[neil@rhel8-demo]$ sudo dnf update

We trust you have received the usual lecture from the local System

Administrator. It usually boils down to these three things:

#1) Respect the privacy of others.

#2) Think before you type.

#3) With great power comes great responsibility.

[sudo] password for neil:

Updating Subscription Management repositories.

.

.

The reason for raising this issue so early in the book is that many of the command-line examples outlined in this book will require root privileges. Rather than repetitively preface every command-line example with directions to run the command as root, the command prompt at the start of the line will be used to indicate whether or not the command needs to be performed as root. If the command can be run as a regular user, the command will be prefixed with a $ command prompt as follows:

$ date

If, on the other hand, the command requires root privileges, the command will be preceded by a # command prompt:

# dnf install openssh

1.2 Feedback

We want you to be satisfied with your purchase of this book. If you find any errors in the book, or have any comments, questions or concerns please contact us at [email protected].

1.3 Errata

While we make every effort to ensure the accuracy of the content of this book, it is inevitable that a book covering a subject area of this size and complexity may include some errors and oversights. Any known issues with the book will be outlined, together with solutions, at the f...

Table of contents

• 1. Introduction
• 2. A Brief History of Red Hat Linux
• 3. Installing RHEL 8 on a Clean Disk Drive
• 4. Dual Booting RHEL 8 with Windows
• 5. Allocating Windows Disk Partitions to RHEL 8
• 6. A Guided Tour of the GNOME 3 Desktop
• 7. An Overview of the RHEL 8 Cockpit Web Interface
• 8. Using the Bash Shell on RHEL 8
• 9. Managing RHEL 8 Users and Groups
• 10. Understanding RHEL 8 Software Installation and Management
• 11. Configuring RHEL 8 systemd Units
• 12. RHEL 8 Network Management
• 13. Basic RHEL 8 Firewall Configuration with firewalld
• 14. Configuring SSH Key-based Authentication on RHEL 8
• 15. RHEL 8 Remote Desktop Access with VNC
• 16. Displaying RHEL 8 Applications Remotely (X11 Forwarding)
• 17. Using NFS to Share RHEL 8 Files with Remote Systems
• 18. Sharing Files between RHEL 8 and Windows Systems with Samba
• 19. An Overview of Virtualization Techniques
• 20. Installing KVM Virtualization on RHEL 8
• 21. Creating KVM Virtual Machines using Cockpit and virt-manager
• 22. Creating KVM Virtual Machines with virt-install and virsh
• 23. Creating a RHEL 8 KVM Networked Bridge Interface
• 24. Managing KVM using the virsh Command-Line Tool
• 25. An Introduction to Linux Containers
• 26. Working with Containers on RHEL 8
• 27. Setting Up a RHEL 8 Web Server
• 28. Configuring a RHEL 8 Postfix Email Server
• 29. Adding a New Disk Drive to a RHEL 8 System
• 30. Adding a New Disk to a RHEL 8 Volume Group and Logical Volume
• 31. Adding and Managing RHEL 8 Swap Space
• Index