Red Hat Enterprise Linux 8 Essentials

✍ Scribed by Neil Smyth

• Tongue: English
• Leaves: 298
• Category: Library

✦ Synopsis

The content of this book is provided for informational purposes only. Neither the publisher nor the author offers any warranties or representation, express or implied, with regard to the accuracy of information contained in this book, nor do they accept any liability for any loss or damage arising from any errors or omissions.
This book contains trademarked terms that are used solely for editorial purposes and to the benefit of the respective trademark owner. The terms used within this book are not intended as infringement of any trademarks.

✦ Table of Contents

1. Introduction
   1.1 Superuser Conventions
   1.2 Feedback
   1.3 Errata
2. A Brief History of Red Hat Linux
   2.1 What exactly is Linux?
   2.2 UNIX Origins
   2.3 Who Created Linux?
   2.4 The Early Days of Red Hat
   2.5 Red Hat Support
   2.6 Open Source
   2.7 The Fedora Project
   2.8 CentOS - The Free Alternative
   2.9 Summary
3. Installing RHEL 8 on a Clean Disk Drive
   3.1 Obtaining the Red Hat Enterprise Linux Installation Media
   3.2 Writing the ISO Installation Image to a USB Drive
   3.2.1 Linux
   3.2.2 macOS
   3.2.3 Windows
   3.3 Installing Red Hat Enterprise Linux 8
   3.4 Partitioning a Disk for RHEL 8
   3.5 The Physical Installation
   3.6 Final Configuration Steps
   3.7 Installing Updates
   3.8 Displaying Boot Messages
   3.9 Summary
4. Dual Booting RHEL 8 with Windows
   4.1 Partition Resizing
   4.2 Editing the RHEL 8 Boot Menu
   4.3 Changing the Default Boot Option
   4.4 Accessing the Windows Partition from RHEL 8
   4.5 Summary
5. Allocating Windows Disk Partitions to RHEL 8
   5.1 Unmounting the Windows Partition
   5.2 Deleting the Windows Partitions from the Disk
   5.3 Formatting the Unallocated Disk Partition
   5.4 Mounting the New Partition
   5.5 Editing the Boot Menu
   5.6 Summary
6. A Guided Tour of the GNOME 3 Desktop
   6.1 Installing the GNOME Desktop
   6.2 An Overview of the GNOME 3 Desktop
   6.3 Launching Activities
   6.4 Managing Windows
   6.5 Using Workspaces
   6.6 Calendar and Notifications
   6.7 Desktop Settings
   6.8 Summary
7. An Overview of the RHEL 8 Cockpit Web Interface
   7.1 An Overview of Cockpit
   7.2 Installing and Enabling Cockpit
   7.3 Accessing Cockpit
   7.4 System
   7.5 Logs
   7.6 Storage
   7.7 Networking
   7.8 Podman Containers
   7.9 Virtual Machines
   7.10 Accounts
   7.11 Services
   7.12 Applications
   7.13 Diagnostic Reports
   7.14 Kernel Dump
   7.15 SELinux
   7.16 Software Updates
   7.17 Subscriptions
   7.18 Terminal
   7.19 Connecting to Multiple Servers
   7.20 Enabling Stored Metrics
   7.21 Summary
8. Using the Bash Shell on RHEL 8
   8.1 What is a Shell?
   8.2 Gaining Access to the Shell
   8.3 Entering Commands at the Prompt
   8.4 Getting Information about a Command
   8.5 Bash Command-line Editing
   8.6 Working with the Shell History
   8.7 Filename Shorthand
   8.8 Filename and Path Completion
   8.9 Input and Output Redirection
   8.10 Working with Pipes in the Bash Shell
   8.11 Configuring Aliases
   8.12 Environment Variables
   8.13 Writing Shell Scripts
   8.14 Summary
9. Managing RHEL 8 Users and Groups
   9.1 User Management from the Command-line
   9.2 User Management with Cockpit
   9.3 Summary
10. Understanding RHEL 8 Software Installation and Management
    10.1 Repositories
    10.2 The BaseOS Repository
    10.3 The AppStream Repository
    10.4 Summary
11. Configuring RHEL 8 systemd Units
    11.1 Understanding RHEL 8 systemd Targets
    11.2 Understanding RHEL 8 systemd Services
    11.3 RHEL 8 systemd Target Descriptions
    11.4 Identifying and Configuring the Default Target
    11.5 Understanding systemd Units and Unit Types
    11.6 Dynamically Changing the Current Target
    11.7 Enabling, Disabling and Masking systemd Units
    11.8 Working with systemd Units in Cockpit
    11.9 Summary
12. RHEL 8 Network Management
    12.1 An Introduction to NetworkManager
    12.2 Installing and Enabling NetworkManager
    12.3 Basic nmcli Commands
    12.4 Working with Connection Profiles
    12.5 Interactive Editing
    12.6 Configuring NetworkManager Permissions
    12.7 Summary
13. Basic RHEL 8 Firewall Configuration with firewalld
    13.1 An Introduction to firewalld
    13.1.1 Zones
    13.1.2 Interfaces
    13.1.3 Services
    13.1.4 Ports
    13.2 Checking firewalld Status
    13.3 Configuring Firewall Rules with firewall-cmd
    13.3.1 Identifying and Changing the Default Zone
    13.3.2 Displaying Zone Information
    13.3.3 Adding and Removing Zone Services
    13.3.4 Working with Port-based Rules
    13.3.5 Creating a New Zone
    13.3.6 Changing Zone/Interface Assignments
    13.3.7 Masquerading
    13.3.8 Adding ICMP Rules
    13.3.9 Implementing Port Forwarding
    13.4 Managing firewalld from the Cockpit Interface
    13.5 Managing firewalld using firewall-config
    13.6 Summary
14. Configuring SSH Key-based Authentication on RHEL 8
    14.1 An Overview of Secure Shell (SSH)
    14.2 SSH Key-based Authentication
    14.3 Setting Up Key-based Authentication
    14.4 SSH Key-based Authentication from Linux and macOS Clients
    14.5 Managing Multiple Keys
    14.6 SSH Key-based Authentication from Windows 10 Clients
    14.7 SSH Key-based Authentication using PuTTY
    14.8 Generating a Private Key with PuTTYgen
    14.9 Installing the Public Key for a Google Cloud Instance
    14.10 Summary
15. RHEL 8 Remote Desktop Access with VNC
    15.1 Secure and Insecure Remote Desktop Access
    15.2 Installing the GNOME Desktop Environment
    15.3 Installing VNC on RHEL 8
    15.4 Configuring the VNC Server
    15.5 Connecting to a VNC Server
    15.6 Establishing a Secure Remote Desktop Session
    15.7 Establishing a Secure Tunnel on Windows using PuTTY
    15.8 Shutting Down a Desktop Session
    15.9 Troubleshooting a VNC Connection
    15.10 Summary
16. Displaying RHEL 8 Applications Remotely (X11 Forwarding)
    16.1 Requirements for Remotely Displaying RHEL 8 Applications
    16.2 Remotely Displaying a RHEL 8 Application
    16.3 Trusted X11 Forwarding
    16.4 Compressed X11 Forwarding
    16.5 Displaying Remote RHEL 8 Apps on Windows
    16.6 Summary
17. Using NFS to Share RHEL 8 Files with Remote Systems
    17.1 Ensuring NFS Services are running on RHEL 8
    17.2 Configuring the RHEL 8 Firewall to Allow NFS Traffic
    17.3 Specifying the Folders to be Shared
    17.4 Accessing Shared RHEL 8 Folders
    17.5 Mounting an NFS Filesystem on System Startup
    17.6 Unmounting an NFS Mount Point
    17.7 Accessing NFS Filesystems in Cockpit
    17.8 Summary
18. Sharing Files between RHEL 8 and Windows Systems with Samba
    18.1 Samba and Samba Client
    18.2 Installing Samba on a RHEL 8 System
    18.3 Configuring the RHEL 8 Firewall to Enable Samba
    18.4 Configuring the smb.conf File
    18.4.1 Configuring the [global] Section
    18.4.2 Configuring a Shared Resource
    18.4.3 Removing Unnecessary Shares
    18.5 Configuring SELinux for Samba
    18.6 Creating a Samba User
    18.7 Testing the smb.conf File
    18.8 Starting the Samba and NetBIOS Name Services
    18.9 Accessing Samba Shares
    18.10 Accessing Windows Shares from RHEL 8
    18.11 Summary
19. An Overview of Virtualization Techniques
    19.1 Guest Operating System Virtualization
    19.2 Hypervisor Virtualization
    19.2.1 Paravirtualization
    19.2.2 Full Virtualization
    19.2.3 Hardware Virtualization
    19.3 Virtual Machine Networking
    19.4 Summary
20. Installing KVM Virtualization on RHEL 8
    20.1 An Overview of KVM
    20.2 KVM Hardware Requirements
    20.3 Preparing RHEL 8 for KVM Virtualization
    20.4 Verifying the KVM Installation
    20.5 Summary
21. Creating KVM Virtual Machines using Cockpit and virt-manager
    21.1 Installing the Cockpit Virtual Machines Module
    21.2 Creating a Virtual Machine in Cockpit
    21.3 Starting the Installation
    21.4 Working with Storage Volumes and Storage Pools
    21.5 Creating a Virtual Machine using virt-manager
    21.6 Starting the Virtual Machine Manager
    21.7 Configuring the KVM Virtual System
    21.8 Starting the KVM Virtual Machine
    21.9 Summary
22. Creating KVM Virtual Machines with virt-install and virsh
    22.1 Running virt-install to build a KVM Guest System
    22.2 An Example RHEL 8 virt-install Command
    22.3 Starting and Stopping a Virtual Machine from the Command-Line
    22.4 Creating a Virtual Machine from a Configuration File
    22.5 Summary
23. Creating a RHEL 8 KVM Networked Bridge Interface
    23.1 Getting the Current Network Settings
    23.2 Creating a Network Bridge from the Command-Line
    23.3 Declaring the KVM Bridged Network
    23.4 Using a Bridge Network in a Virtual Machine
    23.5 Creating a Bridge Network using nm-connection-editor
    23.6 Summary
24. Managing KVM using the virsh Command-Line Tool
    24.1 The virsh Shell and Command-Line
    24.2 Listing Guest System Status
    24.3 Starting a Guest System
    24.4 Shutting Down a Guest System
    24.5 Suspending and Resuming a Guest System
    24.6 Saving and Restoring Guest Systems
    24.7 Rebooting a Guest System
    24.8 Configuring the Memory Assigned to a Guest OS
    24.9 Summary
25. An Introduction to Linux Containers
    25.1 Linux Containers and Kernel Sharing
    25.2 Container Uses and Advantages
    25.3 RHEL 8 Container Tools
    25.4 Container Catalogs, Repositories and Registries
    25.5 Container Networking
    25.6 Summary
26. Working with Containers on RHEL 8
    26.1 Installing the Container Tools
    26.2 Logging in to the Red Hat Container Registry
    26.3 Pulling a Container Image
    26.4 Running the Image in a Container
    26.5 Managing a Container
    26.6 Saving a Container to an Image
    26.7 Removing an Image from Local Storage
    26.8 Removing Containers
    26.9 Building a Container with Buildah
    26.10 Building a Container from Scratch
    26.11 Container Bridge Networking
    26.12 Managing Containers in Cockpit
    26.13 Summary
27. Setting Up a RHEL 8 Web Server
    27.1 Requirements for Configuring a RHEL 8 Web Server
    27.2 Installing the Apache Web Server Packages
    27.3 Configuring the Firewall
    27.4 Port Forwarding
    27.5 Starting the Apache Web Server
    27.6 Testing the Web Server
    27.7 Configuring the Apache Web Server for Your Domain
    27.8 The Basics of a Secure Web Site
    27.9 Configuring Apache for HTTPS
    27.10 Obtaining an SSL Certificate
    27.11 Summary
28. Configuring a RHEL 8 Postfix Email Server
    28.1 The structure of the Email System
    28.1.1 Mail User Agent
    28.1.2 Mail Transfer Agent
    28.1.3 Mail Delivery Agent
    28.1.4 SMTP
    28.1.5 SMTP Relay
    28.2 Configuring a RHEL 8 Email Server
    28.3 Postfix Pre-Installation Steps
    28.4 Firewall/Router Configuration
    28.5 Installing Postfix on RHEL 8
    28.6 Configuring Postfix
    28.7 Configuring DNS MX Records
    28.8 Starting Postfix on a RHEL 8 System
    28.9 Testing Postfix
    28.10 Sending Mail via an SMTP Relay Server
    28.11 Summary
29. Adding a New Disk Drive to a RHEL 8 System
    29.1 Mounted File Systems or Logical Volumes
    29.2 Finding the New Hard Drive
    29.3 Creating Linux Partitions
    29.4 Creating a File System on a RHEL 8 Disk Partition
    29.5 An Overview of Journaled File Systems
    29.6 Mounting a File System
    29.7 Configuring RHEL 8 to Automatically Mount a File System
    29.8 Adding a Disk Using Cockpit
    29.9 Summary
30. Adding a New Disk to a RHEL 8 Volume Group and Logical Volume
    30.1 An Overview of Logical Volume Management (LVM)
    30.1.1 Volume Group (VG)
    30.1.2 Physical Volume (PV)
    30.1.3 Logical Volume (LV)
    30.1.4 Physical Extent (PE)
    30.1.5 Logical Extent (LE)
    30.2 Getting Information about Logical Volumes
    30.3 Adding Additional Space to a Volume Group from the Command-Line
    30.4 Adding Additional Space to a Volume Group using Cockpit
    30.5 Summary
31. Adding and Managing RHEL 8 Swap Space
    31.1 What is Swap Space?
    31.2 Recommended Swap Space for RHEL 8
    31.3 Identifying Current Swap Space Usage
    31.4 Adding a Swap File to a RHEL 8 System
    31.5 Adding Swap as a Partition
    31.6 Adding Space to a RHEL 8 LVM Swap Volume
    31.7 Adding Swap Space to the Volume Group
    31.8 Summary
    Index