RHCSA Red Hat Enterprise Linux 8: Training and Exam Preparation Guide (EX200)

Title Page
Copyright Page
Preface
Acknowledgments
About the Author
About this Book
Table of Contents
List of Figures
List of Tables
01. Local Installation
	A Quick Look at Linux Development
		Linux History in a Nutshell
		Linux from Red Hat
	Lab Infrastructure for Practice
		What is Needed for the Lab?
		The RHEL Installer Program
		Where Do Installation Logs Go?
		Virtual Console Screens
	Exercise 1-1: Download and Install VirtualBox Software, and Create a Virtual Machine
		Downloading and Installing VirtualBox
		Creating a Virtual Machine
	Exercise 1-2: Download and Install RHEL 8
		Downloading RHEL 8 ISO Image
		Attaching RHEL 8 ISO Image to the Virtual Machine
		Launching the Installer
		Adding Support for Keyboards and Languages
		Configuring Time & Date
		Choosing an Installation Source
		Selecting Software to be Installed
		Configuring Installation Destination
		Configuring Network and Hostname
		Beginning Installation
		Setting root Password and Creating a User Account
		Concluding Installation
		Changing Default Boot Order
		Performing Post-Installation Tasks
	Logging In and Out
		Logging In for the First Time
		Logging Out
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 1-1: Build RHEL8-VM2 (server2)
02. Initial Interaction with the System
	Linux Graphical Environment
		Display/Login Manager
		Desktop Environment
	Linux Directory Structure and File Systems
		Top-Level Directories
		File System Categories
		The Root File System (/), Disk-Based
		The Boot File System (/boot) – Disk-Based
		The Home Directory (/home)
		The Optional Directory (/opt)
		The UNIX System Resources Directory (/usr)
		The Variable Directory (/var)
		The Temporary Directory (/tmp)
		The Devices File System (/dev), Virtual
		The Procfs File System (/proc), Virtual
		The Runtime File System (/run), Virtual
		The System File System (/sys), Virtual
		Viewing Directory Hierarchy
	Basic System Commands
		Starting a GNOME Terminal Session
		Understanding the Command Mechanics
		Listing Files and Directories
		Printing Working Directory
		Navigating Directories
		Identifying Terminal Device File
		Inspecting System’s Uptime and Processor Load
		Clearing the Screen
		Determining Command Path
		Viewing System Information
		Viewing CPU Specs
	Getting Help
		Accessing Manual Pages
		Headings in the Manual
		Manual Sections
		Searching by Keyword
		Exposing Short Description
		The info and pinfo Commands
		Documentation in the /usr/share/doc Directory
		Red Hat Enterprise Linux 8 Documentation
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 2-1: Navigate Linux Directory Tree
		Lab 2-2: Miscellaneous Tasks
		Lab 2-3: Identify System and Kernel Information
		Lab 2-4: Use Help
03. Basic File Management
	Common File Types
		Regular Files
		Directory Files
		Block and Character Special Device Files
		Symbolic Links
	Compression and Archiving
		Using gzip and gunzip
		Using bzip2 and bunzip2
		Differences between gzip and bzip2
		Using tar
		Exercise 3-1: Create Compressed Archives
	File Editing
		Modes of Operation
		Starting vim
		Inserting text
		Navigating within vim
		Deleting Text
		Undoing and Repeating
		Searching for Text
		Replacing Text
		Copying, Moving, and Pasting Text
		Changing Text
		Saving and Quitting vim
	File and Directory Operations
		Creating Files and Directories
		Displaying File Contents
		Counting Words, Lines, and Characters in Text Files
		Copying Files and Directories
		Moving and Renaming Files and Directories
		Removing Files and Directories
	File Linking
		Hard Link
		Soft Link
		Differences between Copying and Linking
		Exercise 3-2: Create and Manage Hard Links
		Exercise 3-3: Create and Manage Soft Links
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 3-1: Archive, List, and Restore Files
		Lab 3-2: Practice the vim Editor
		Lab 3-3: File and Directory Operations
04. Advanced File Management
	File and Directory Access Permissions
		Determining Access Permissions
		Permission Classes
		Permission Types
		Permission Modes
		Modifying Access Permission Bits
		Exercise 4-1: Modify Permission Bits Using Symbolic Form
		Exercise 4-2: Modify Permission Bits Using Octal Form
		Default Permissions
		Calculating Default Permissions
	Special File Permissions
		The setuid Bit on Binary Executable Files
		Exercise 4-3: Test the Effect of setuid Bit on Executable Files
		The setgid Bit on Binary Executable Files
		Exercise 4-4: Test the Effect of setgid Bit on Executable Files
		The setgid Bit on Shared Directories
		Exercise 4-5: Set up Shared Directory for Group Collaboration
		The Sticky Bit on Public and Shared Writable Directories
		Exercise 4-6: Test the Effect of Sticky Bit
	File Searching
		Using the find Command
		Using find with -exec and -ok Flags
		Using the locate Command
	Access Control Lists (ACLs)
		ACL Management Commands
		The getfacl Command
		The setfacl Command
		The Role of the mask Value
		Exercise 4-7: Identify, Apply, and Erase Access ACLs
		Default ACLs
		Exercise 4-8: Apply, Identify, and Erase Default ACLs
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 4-1: Manipulate File Permissions
		Lab 4-2: Configure Group Collaboration and Prevent File Deletion
		Lab 4-3: Find Files
		Lab 4-4: Find Files Using Different Criteria
		Lab 4-5: Apply ACL Settings
05. Basic User Management
	User Login Activity and Information
		Listing Logged-In Users
		Inspecting History of Successful Login Attempts and System Reboots
		Viewing History of Failed User Login Attempts
		Reporting Recent User Login Attempts
		Examining User and Group Information
	Local User Authentication Files
		The passwd File
		The shadow File
		The group File
		The gshadow File
	The useradd and login.defs Configuration Files
	User Account Management
		The useradd, usermod, and userdel Commands
		Exercise 5-1: Create a User Account with Default Attributes
		Exercise 5-2: Create a User Account with Custom Values
		Exercise 5-3: Modify and Delete a User Account
		No-Login (Non-Interactive) User Account
		Exercise 5-4: Create a User Account with No-Login Access
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 5-1: Check User Login Attempts
		Lab 5-2: Verify User and Group Identity
		Lab 5-3: Create Users
		Lab 5-4: Create User with Non-Interactive Shell
06. Advanced User Management
	Password Aging and its Management
		The chage Command
		Exercise 6-1: Set and Confirm Password Aging with chage
		The passwd Command
		Exercise 6-2: Set and Confirm Password Aging with passwd
		The usermod Command
		Exercise 6-3: Lock and Unlock a User Account with usermod and passwd
	Linux Groups and their Management
		The groupadd, groupmod, and groupdel Commands
		Exercise 6-4: Create a Group and Add Members
		Exercise 6-5: Modify and Delete a Group Account
	Substituting Users and Doing as Superuser
		Substituting (or Switching) Users
		Doing as Superuser (or Doing as Substitute User)
	Owning User and Owning Group
		Exercise 6-6: Modify File Owner and Owning Group
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 6-1: Create User and Configure Password Aging
		Lab 6-2: Lock and Unlock User
		Lab 6-3: Modify Group
		Lab 6-4: Configure sudo Access
		Lab 6-5: Modify Owning User and Group
07. The Bash Shell
	The Bourne-Again Shell
		Internal and External Shell Commands
		Shell and Environment Variables
		Setting and Unsetting Variables
		Command and Variable Substitutions
		Exercise 7-1: Modify Primary Command Prompt
		Input, Output, and Error Redirections
		History Substitution
		Editing at the Command Line
		Tab Completion
		Tilde Substitution
		Alias Substitution
		Metacharacters and Wildcard Characters
		Piping Output of One Command as Input to Another
		Quoting Mechanisms
		Regular Expressions
		Running and Controlling Jobs in Foreground and Background
	Shell Startup Files
		System-wide Shell Startup Files
		Per-user Shell Startup Files
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 7-1: Customize the Command Prompt
		Lab 7-2: Redirect the Standard Input, Output, and Error
08. Linux Processes and Task Scheduling
	Processes and Priorities
		Process States
		Viewing and Monitoring Processes with ps
		Viewing and Monitoring Processes with top
		Listing a Specific Process
		Listing Processes by User and Group Ownership
		Understanding Process Niceness
		Viewing and Changing Process Niceness
		Renicing a Running Process
		Controlling Processes with Signals
	Job Scheduling
		Controlling User Access
		Scheduler Log File
		Using at
		Exercise 8-1: Submit, View, List, and Remove an at Job
		Using crontab
		Syntax of User Crontables
		Exercise 8-2: Add, List, and Remove a Cron Job
		Anacron
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 8-1: Nice and Renice a Process
		Lab 8-2: Configure a User Crontab File
09. Basic Package Management
	Package Overview
		Packages and Packaging
		Package Naming
		Package Dependency
		Package Database
		Package Management Tools
	Package Management with rpm
		The rpm Command
		Getting Ready to Use rpm
		Querying Packages
		Installing a Package
		Upgrading a Package
		Freshening a Package
		Overwriting a Package
		Removing a Package
		Extracting Files from an Installable Package
		Validating Package Integrity and Credibility
		Viewing GPG Keys
		Verifying Package Attributes
		Exercise 9-1: Perform Package Management Tasks Using rpm
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 9-1: Install and Verify Packages
		Lab 9-2: Query and Remove Packages
10. Advanced Package Management
	Advanced Package Management Concepts
		Package Groups
		Application Streams and Modules
		BaseOS Repository
		AppStream Repository
		Benefits of Segregation
		Module Streams
		Module Profiles
		dnf/yum Repository
	Software Management with dnf
		dnf Configuration File
		The dnf Command
		Exercise 10-1: Configure Access to Pre-Built ISO Repositories
	Individual Package Management
		Listing Available and Installed Packages
		Installing and Updating Packages
		Exhibiting Package Information
		Removing Packages
		Exercise 10-2: Manipulate Individual Packages
		Determining Provider and Searching Package Metadata
	Package Group Management
		Listing Available and Installed Package Groups
		Installing and Updating Package Groups
		Removing Package Groups
		Exercise 10-3: Manipulate Package Groups
	Module Management
		Listing Available and Installed Modules
		Installing and Updating Modules
		Displaying Module Information
		Removing Modules
		Exercise 10-4: Manipulate Modules
		Switching Module Streams
		Exercise 10-5: Install a Module from an Alternative Stream
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 10-1: Configure Access to RHEL 8 Repositories
		Lab 10-2: Install and Manage Individual Packages
		Lab 10-3: Install and Manage Package Groups
		Lab 10-4: Install and Manage Modules
		Lab 10-5: Switch Module Streams and Install Software
11. Boot Process, GRUB2, and the Linux Kernel
	Linux Boot Process
		The Firmware Phase (BIOS and UEFI)
		The Bootloader Phase
		The Kernel Phase
		The Initialization Phase
	The GRUB2 Bootloader
		Interacting with GRUB2
		Understanding GRUB2 Configuration Files
		Booting into Specific Targets
		Exercise 11-1: Reset the root User Password
	The Linux Kernel
		Kernel Packages
		Analyzing Kernel Version
		Understanding Kernel Directory Structure
		Installing the Kernel
		Exercise 11-2: Download and Install a New Kernel
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 11-1: Modify GRUB2 Timeout
		Lab 11-2: Reset root User Password
		Lab 11-3: Install New Kernel
12. System Initialization, Message Logging, and System Tuning
	System Initialization and Service Management
		Units
		Targets
		The systemctl Command
		Listing and Viewing Units
		Managing Service Units
		Managing Target Units
	System Logging
		The Syslog Configuration File
		Rotating Log Files
		The Boot Log File
		The System Log File
		Logging Custom Messages
	The systemd Journal
		Retrieving and Viewing Messages
		Preserving Journal Information
	System Tuning
		Tuning Profiles
		The tuned-adm Command
		Exercise 12-1: Manage Tuning Profiles
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 12-1: Modify Default Boot Target
		Lab 12-2: Record Custom Alerts
		Lab 12-3: Apply Tuning Profile
13. Basic Storage Partitioning
	Storage Management Overview
		Master Boot Record (MBR)
		GUID Partition Table (GPT)
		Disk Partitions
		Storage Management Tools
		Thin Provisioning
		Adding Storage for Practice
		Exercise 13-1: Add Required Storage to server2
	MBR Storage Management with parted
		Exercise 13-2: Create an MBR Partition
		Exercise 13-3: Delete an MBR Partition
	GPT Storage Management with gdisk
		Exercise 13-4: Create a GPT Partition
		Exercise 13-5: Delete a GPT Partition
	Storage Optimization with Virtual Data Optimizer (VDO)
		How VDO Conserves Storage Space
		Creating and Managing VDO Volumes
		Exercise 13-6: Install Software and Activate VDO
		Exercise 13-7: Create a VDO Volume
		Exercise 13-8: Delete a VDO Volume
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 13-1: Create and Remove Partitions with parted
		Lab 13-2: Create and Remove Partitions with gdisk
		Lab 13-3: Create and Delete VDO Volumes
		Lab 13-4: Disable and Enable VDO Volume Features
14. Advanced Storage Partitioning
	Logical Volume Manager (LVM)
		Physical Volume
		Volume Group
		Physical Extent
		Logical Volume
		Logical Extent
		LVM Operations and Commands
		Exercise 14-1: Create a Physical Volume and Volume Group
		Exercise 14-2: Create Logical Volumes
		Exercise 14-3: Extend a Volume Group and a Logical Volume
		Exercise 14-4: Rename, Reduce, Extend, and Remove Logical Volumes
		Exercise 14-5: Reduce and Remove a Volume Group
		Exercise 14-6: Uninitialize Physical Volumes
	Stratis Volume-Managing File System
		Stratis Management Operations and Command
		Exercise 14-7: Install Software and Activate Stratis
		Exercise 14-8: Create and Confirm a Pool and File System
		Exercise 14-9: Expand and Rename a Pool and File System
		Exercise 14-10: Destroy a File System and Pool
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 14-1: Create Volume Group and Logical Volumes
		Lab 14-2: Expand Volume Group and Logical Volume
		Lab 14-3: Reduce and Remove Logical Volumes
		Lab 14-4: Remove Volume Group and Physical Volumes
		Lab 14-5: Create Stratis Pool
		Lab 14-6: Expand and Destroy Stratis Pool
15. Local File Systems and Swap
	File Systems and File System Types
		Extended File Systems
		XFS File System
		VFAT File System
		ISO9660 File System
	File System Management
		File System Administration Commands
		Mounting and Unmounting File Systems
		Determining the UUID of a File System
		Labeling a File System
		Automatically Mounting a File System at Reboots
		Monitoring File System Usage
		Calculating Disk Usage
		Exercise 15-1: Create and Mount Ext4, VFAT, and XFS File Systems in Partitions
		Exercise 15-2: Create and Mount XFS File System in VDO Volume
		Exercise 15-3: Create and Mount Ext4 and XFS File Systems in LVM Logical Volumes
		Exercise 15-4: Resize Ext4 and XFS File Systems in LVM Logical Volumes
		Exercise 15-5: Create, Mount, and Expand XFS File System in Stratis Volume
	Swap and its Management
		Determining Current Swap Usage
		Prioritizing Swap Spaces
		Swap Administration Commands
		Exercise 15-6: Create and Activate Swap in Partition and Logical Volume
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 15-1: Create VFAT, Ext4, and XFS File Systems in Partitions and Mount Persistently
		Lab 15-2: Create XFS File System in VDO Volume and Mount Persistently
		Lab 15-3: Create Ext4 and XFS File Systems in LVM Logical Volumes and Mount Persistently
		Lab 15-4: Extend Ext4 and XFS File Systems in LVM Logical Volumes
		Lab 15-5: Create XFS File System in Stratis Volume and Mount Persistently
		Lab 15-6: Create Swap in Partition and LVM Logical Volume and Activate Persistently
16. Remote File System
	Network File System
		Benefits of Using NFS
		NFS Versions
	NFS Server and Client Configuration
		Exercise 16-1: Export Share on NFS Server
		Exercise 16-2: Mount Share on NFS Client
	Auto File System (AutoFS)
		Benefits of Using AutoFS
		How AutoFS Works
		AutoFS Configuration File
		AutoFS Maps
		Exercise 16-3: Access NFS Share Using Direct Map
		Exercise 16-4: Access NFS Share Using Indirect Map
		Automounting User Home Directories
		Exercise 16-5: Automount User Home Directories Using Indirect Map
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 16-1: Configure NFS Share and Automount with Direct Map
		Lab 16-2: Automount NFS Share with Indirect Map
17. Networking, Network Devices, and Network Connections
	Networking Fundamentals
		Hostname
		Exercise 17-1: Change System Hostname
		IPv4 Address
		Network Classes
		Subnetting
		Subnet Mask
		Classless Inter-Domain Routing (CIDR) Notation
		Protocol
		TCP and UDP Protocols
		Well-Known Ports
		ICMP Protocol
		Ethernet Address
		IPv6 Address
		Major Differences between IPv4 and IPv6
	Network Devices and Connections
		Consistent Network Device Naming
		Understanding Interface Connection Profile
		Exercise 17-2: Add Network Devices to server10 and server20
		Network Device and Connection Administration Tools
		Exercise 17-3: Configure New Network Connection Manually
		The NetworkManager Service
		The nmcli Command
		Exercise 17-4: Configure New Network Connection Using nmcli
		Understanding Hosts Table
		Testing Network Connectivity
		Exercise 17-5: Update Hosts Table and Test Connectivity
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 17-1: Add New Interface and Configure Connection Profile with nmcli
		Lab 17-2: Add New Interface and Configure Connection Profile Manually
18. Time Synchronization and Hostname Resolution
	Time Synchronization
		Time Sources
		NTP Roles
		Stratum Levels
		Chrony Configuration File
		Chrony Daemon and Command
		Exercise 18-1: Configure NTP Client
		Displaying and Setting System Date and Time
	DNS and Name Resolution
		DNS Name Space and Domains
		DNS Roles
		Understanding Resolver Configuration File
		Performing Name Resolution with dig
		Performing Name Resolution with host
		Performing Name Resolution with nslookup
		Performing Name Resolution with getent
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 18-1: Modify System Date and Time
		Lab 18-2: Configure Chrony
19. The Secure Shell Service
	The OpenSSH Service
		Common Encryption Techniques
		Authentication Methods
		OpenSSH Protocol Version and Algorithms
		OpenSSH Packages
		OpenSSH Server Daemon and Client Commands
		Server Configuration File
		Client Configuration File
	System Access and File Transfer
		Exercise 19-1: Access RHEL System from Another RHEL System
		Exercise 19-2: Access RHEL System from Windows
		Exercise 19-3: Generate, Distribute, and Use SSH Keys
		Executing Commands Remotely Using ssh
		Copying Files Remotely Using scp
		Transferring Files Remotely Using sftp
		Synchronizing Files Remotely Using rsync
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 19-1: Establish Key-Based Authentication
		Lab 19-2: Test the Effect of PermitRootLogin Directive
20.The Linux Firewall
	Firewall Overview
		Overview of firewalld
		firewalld Zones
		Zone Configuration Files
		firewalld Services
		Service Configuration Files
	Firewall Management
		The firewall-cmd Command
		Querying the Operational Status of firewalld
		Exercise 20-1: Add Services and Ports, and Manage Zones
		Exercise 20-2: Remove Services and Ports, and Manage Zones
		Exercise 20-3: Test the Effect of Firewall Rule
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 20-1: Add Service to Firewall
		Lab 20-2: Add Port Range to Firewall
21.Security Enhanced Linux
	Security Enhanced Linux
		Terminology
		SELinux Contexts for Users
		SELinux Contexts for Processes
		SELinux Contexts for Files
		Copying, Moving, and Archiving Files with SELinux Contexts
		SELinux Contexts for Ports
		Domain Transitioning
		SELinux Booleans
	SELinux Administration
		Management Commands
		Viewing and Controlling SELinux Operational State
		Querying Status
		Exercise 21-1: Modify SELinux File Context
		Exercise 21-2: Add and Apply File Context
		Exercise 21-3: Add and Delete Network Ports
		Exercise 21-4: Copy Files with and without Context
		Exercise 21-5: View and Toggle SELinux Boolean Values
		Monitoring and Analyzing SELinux Violations
	Chapter Summary
	Check Your Understanding
	Answers to Check Your Understanding
	Do-It-Yourself Challenge Labs
		Lab 21-1: Disable and Enable the SELinux Operating Mode
		Lab 21-2: Modify Context on Files
		Lab 21-3: Add Network Port to Policy Database
		Lab 21-4: Copy Files with and without Context
		Lab 21-5: Flip SELinux Booleans
Appendix A: Sample RHCSA Exam 1
Appendix B: Sample RHCSA Exam 2
Appendix C: Sample RHCSA Exam 3
Appendix D: Sample RHCSA Exam 4
Bibliography
Glossary
Index