book

CentOS 8 Essentials

by Neil Smyth

May 2020

Beginner

261 pages

6h 32m

English

Packt Publishing

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1.1 Superuser Conventions1.2 Feedback1.3 Errata
2.1 What exactly is Linux?2.2 UNIX Origins2.3 Who Created Linux?2.4 The Early Days of Red Hat2.5 Red Hat Support2.6 Open Source2.7 The Fedora Project2.8 CentOS - The Free Alternative2.9 Summary
3.1 Obtaining the CentOS Installation Media3.2 Writing the ISO Installation Image to a USB Drive3.2.1 Linux3.2.2 macOS3.2.3 Windows3.3 Installing CentOS 83.4 Partitioning a Disk for CentOS 83.5 The Physical Installation 3.6 Final Configuration Steps3.7 Installing Updates3.8 Displaying Boot Messages3.9 Summary
4.1 Partition Resizing4.2 Editing the CentOS 8 Boot Menu 4.3 Changing the Default Boot Option4.4 Accessing the Windows Partition from CentOS 84.5 Summary
5.1 Unmounting the Windows Partition5.2 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 Menu5.6 Summary
6.1 Installing the GNOME Desktop6.2 An Overview of the GNOME 3 Desktop6.3 Launching Activities6.4 Managing Windows6.5 Using Workspaces6.6 Calendar and Notifications6.7 Desktop Settings6.8 Summary
7.1 An Overview of Cockpit7.2 Installing and Enabling Cockpit7.3 Accessing Cockpit7.4 System7.5 Logs7.6 Storage7.7 Networking7.8 Virtual Machines7.9 Accounts7.10 Services7.11 Applications7.12 Diagnostic Reports7.13 Kernel Dump7.14 SELinux7.15 Software Updates7.16 Terminal7.17 Connecting to Multiple Servers7.18 Enabling Stored Metrics7.19 Summary
8.1 What is a Shell?8.2 Gaining Access to the Shell8.3 Entering Commands at the Prompt8.4 Getting Information about a Command8.5 Bash Command-line Editing8.6 Working with the Shell History8.7 Filename Shorthand8.8 Filename and Path Completion8.9 Input and Output Redirection8.10 Working with Pipes in the Bash Shell8.11 Configuring Aliases8.12 Environment Variables8.13 Writing Shell Scripts8.14 Summary
9.1 User Management from the Command-line 9.2 User Management with Cockpit9.3 Summary
11.1 Understanding CentOS 8 systemd Targets11.2 Understanding CentOS 8 systemd Services11.3 CentOS 8 systemd Target Descriptions11.4 Identifying and Configuring the Default Target11.5 Understanding systemd Units and Unit Types11.6 Dynamically Changing the Current Target11.7 Enabling, Disabling and Masking systemd Units11.8 Working with systemd Units in Cockpit11.9 Summary

12.1 An Introduction to NetworkManager12.2 Installing and Enabling NetworkManager12.3 Basic nmcli Commands12.4 Working with Connection Profiles12.5 Interactive Editing12.6 Configuring NetworkManager Permissions12.7 Summary
13.1 An Introduction to firewalld13.1.1 Zones13.1.2 Interfaces13.1.3 Services13.1.4 Ports13.2 Checking firewalld Status 13.3 Configuring Firewall Rules with firewall-cmd13.3.1 Identifying and Changing the Default Zone13.3.2 Displaying Zone Information13.3.3 Adding and Removing Zone Services13.3.4 Working with Port-based Rules13.3.5 Creating a New Zone13.3.6 Changing Zone/Interface Assignments13.3.7 Masquerading 13.3.8 Adding ICMP Rules13.3.9 Implementing Port Forwarding13.4 Managing firewalld from the Cockpit Interface13.5 Managing firewalld using firewall-config13.6 Summary
14.1 An Overview of Secure Shell (SSH)14.2 SSH Key-based Authentication14.3 Setting Up Key-based Authentication14.4 SSH Key-based Authentication from Linux and macOS Clients14.5 Managing Multiple Keys14.6 SSH Key-based Authentication from Windows 10 Clients14.7 SSH Key-based Authentication using PuTTY14.8 Generating a Private Key with PuTTYgen14.9 Installing the Public Key for a Google Cloud Instance14.10 Summary
15.1 Secure and Insecure Remote Desktop Access15.2 Installing the GNOME Desktop Environment15.3 Installing VNC on CentOS 815.4 Configuring the VNC Server15.5 Connecting to a VNC Server15.6 Establishing a Secure Remote Desktop Session 15.7 Establishing a Secure Tunnel on Windows using PuTTY15.8 Shutting Down a Desktop Session15.9 Troubleshooting a VNC Connection15.10 Summary
16.1 Requirements for Remotely Displaying CentOS 8 Applications 16.2 Remotely Displaying a CentOS 8 Application 16.3 Trusted X11 Forwarding 16.4 Compressed X11 Forwarding 16.5 Displaying Remote CentOS 8 Apps on Windows16.6 Summary
17.1 Ensuring NFS Services are running on CentOS 817.2 Configuring the CentOS 8 Firewall to Allow NFS Traffic 17.3 Specifying the Folders to be Shared 17.4 Accessing Shared CentOS 8 Folders 17.5 Mounting an NFS Filesystem on System Startup 17.6 Unmounting an NFS Mount Point 17.7 Accessing NFS Filesystems in Cockpit17.8 Summary
18.1 Samba and Samba Client18.2 Installing Samba on a CentOS 8 System 18.3 Configuring the CentOS 8 Firewall to Enable Samba 18.4 Configuring the smb.conf File18.4.1 Configuring the [global] Section18.4.2 Configuring a Shared Resource18.4.3 Removing Unnecessary Shares18.5 Configuring SELinux for Samba18.6 Creating a Samba User18.7 Testing the smb.conf File18.8 Starting the Samba and NetBIOS Name Services18.9 Accessing Samba Shares18.10 Accessing Windows Shares from CentOS 818.11 Summary
19.1 Guest Operating System Virtualization 19.2 Hypervisor Virtualization 19.2.1 Paravirtualization 19.2.2 Full Virtualization19.2.3 Hardware Virtualization 19.3 Virtual Machine Networking19.4 Summary
20.1 An Overview of KVM 20.2 KVM Hardware Requirements20.3 Preparing CentOS 8 for KVM Virtualization 20.4 Verifying the KVM Installation20.5 Summary
21.1 Installing the Cockpit Virtual Machines Module21.2 Creating a Virtual Machine in Cockpit21.3 Starting the Installation21.4 Creating a Virtual Machine using virt-manager21.5 Starting the Virtual Machine Manager21.6 Configuring the KVM Virtual System 21.7 Starting the KVM Virtual Machine 21.8 Summary
22.1 Running virt-install to build a KVM Guest System 22.2 An Example CentOS 8 virt-install Command 22.3 Starting and Stopping a Virtual Machine from the Command-Line22.4 Creating a Virtual Machine from a Configuration File22.5 Summary
23.1 Getting the Current Network Settings23.2 Creating a Network Bridge from the Command-Line23.3 Declaring the KVM Bridged Network23.4 Using a Bridge Network in a Virtual Machine23.5 Creating a Bridge Network using nm-connection-editor23.6 Summary
24.1 The virsh Shell and Command-Line24.2 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
25.1 Linux Containers and Kernel Sharing25.2 Container Uses and Advantages25.3 CentOS 8 Container Tools25.4 The Docker Registry25.5 Container Networking25.6 Summary
26.1 Pulling a Container Image26.2 Running the Image in a Container26.3 Managing a Container26.4 Saving a Container to an Image26.5 Removing an Image from Local Storage26.6 Removing Containers26.7 Building a Container with Buildah26.8 Building a Container from Scratch26.9 Container Bridge Networking26.10 Summary
27.1 Requirements for Configuring a CentOS 8 Web Server 27.2 Installing the Apache Web Server Packages27.3 Configuring the Firewall27.4 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 Site27.9 Configuring Apache for HTTPS27.10 Obtaining an SSL Certificate27.11 Summary
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 Relay28.2 Configuring a CentOS 8 Email Server 28.3 Postfix Pre-Installation Steps 28.4 Firewall/Router Configuration28.5 Installing Postfix on CentOS 828.6 Configuring Postfix 28.7 Configuring DNS MX Records28.8 Starting Postfix on a CentOS 8 System28.9 Testing Postfix28.10 Sending Mail via an SMTP Relay Server28.11 Summary
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 CentOS 8 Disk Partition 29.5 An Overview of Journaled File Systems29.6 Mounting a File System 29.7 Configuring CentOS 8 to Automatically Mount a File System 29.8 Adding a Disk Using Cockpit29.9 Summary
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 Cockpit30.5 Summary
31.1 What is Swap Space?31.2 Recommended Swap Space for CentOS 831.3 Identifying Current Swap Space Usage31.4 Adding a Swap File to a CentOS 8 System31.5 Adding Swap as a Partition31.6 Adding Space to a CentOS 8 LVM Swap Volume31.7 Adding Swap Space to the Volume Group31.8 Summary

Overview

CentOS 8 Essentials serves as your comprehensive guide to mastering the CentOS 8 Linux distribution, whether you're setting it up for personal use or managing servers in a professional setting. From installation to configuring advanced network setups, this book covers it all, equipping you with the know-how to harness the power of this versatile operating system.

What this Book will help me do

Install CentOS 8 in a dual boot configuration, integrate it into your workflow, and navigate its GNOME desktop environment.
Manage users, groups, and software packages efficiently using system administration tools provided by CentOS 8.
Configure and utilize KVM virtualization technology to deploy virtual machines on CentOS 8.
Implement secure file sharing between Windows and Linux systems using Samba and NFS.
Set up and manage a CentOS-based server environment, including firewalls, email, and web servers.

Author(s)

Neil Smyth, the author of CentOS 8 Essentials, has an extensive background in Linux development and system administration. With years of experience writing concise technical documentation, Neil effectively conveys complex concepts in an accessible and engaging manner. His hands-on approach ensures readers can confidently apply the lessons from his books to their own environments.

Who is it for?

This book is perfectly suited for IT professionals, system administrators, and developers looking to gain a strong foundation in CentOS 8. If you're a beginner eager to learn Linux basics or a seasoned admin exploring CentOS as a Red Hat-based solution, this guide will provide you with actionable knowledge to enhance your expertise and tackle real-world use cases.