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CompTIA Linux+ Portable Command Guide: All the commands for the CompTIA XK0-004 exam in one compact, portable resource, 2nd Edition

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CompTIA Linux+ Portable Command Guide: All the commands for the CompTIA XK0-004 exam in one compact, portable resource, 2nd Edition

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  • Summarizes all commands, keywords, command arguments, and associated prompts
  • Presents configuration examples to show exactly how these commands are used
  • The perfect take-anywhere single-source resource for both exam study and day-to-day Linux administration: no need for thick books or even Web access!


  • Copyright 2020
  • Dimensions: 6" x 9"
  • Pages: 416
  • Edition: 2nd
  • Book
  • ISBN-10: 0-13-559184-8
  • ISBN-13: 978-0-13-559184-0

For each exam objective, the key commands and configuration files will be detailed. The CompTIA Linux+ Portable Command Guide provides a single point of reference while studying for the certification exams as well as a valuable resource after the candidate has successfully passed the exams.

The guide summarizes all commands, keywords, command arguments, and associated prompts. Configuration examples are provided throughout the book to give a better understanding of how these commands are used. This guide is not meant to replace any existing learning materials but rather serve as a supplementary guide to assist readers in the proper use of the many different commands to use on a regular basis and that are required to successfully pass the exams.

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Table of Contents

Introduction xxx

Part I: Hardware and System Confi guration
CHAPTER 1 Explain Linux boot process concepts 1
Boot Loaders 1
Boot Options 3
File Locations 6
Boot Modules and Files 7
Kernel Panic 9
CHAPTER 2 Given a scenario, install, confi gure, and monitor kernel
modules 11
Commands 11
Files 15
CHAPTER 3 Given a scenario, confi gure and verify network connection parameters 17
Diagnostic Tools 18
Configuration Files 28
Bonding 34
CHAPTER 4 Given a scenario, manage storage in a Linux environment 37
Basic Partitions 38
Filesystem Hierarchy 40
Device Mapper 41
Tools 44
Location 54
Filesystem Types 58
CHAPTER 5 Compare and contrast cloud and virtualization concepts and technologies 59
Templates 60
Bootstrapping 62
Storage 63
Network Considerations 65
Types of Hypervisors 66
Tools 67
CHAPTER 6 Given a scenario, confi gure localization options 69
File Locations 70
Commands 70
Environment Variables 73
Character Sets 75
UTF-8 75

Part II: Systems Operation and Maintenance
CHAPTER 7 Given a scenario, conduct software installations, confi gurations, updates, and removals 77
Package Types 78
Installation Tools 78
Build Tools 86
Repositories 88
Acquisition Commands 89
CHAPTER 8 Given a scenario, manage users and groups 93
Creation 94
Modification 94
Deletion 96
Queries 96
Quotas 98
Profiles 102
Important Files and File Contents 106
CHAPTER 9 Given a scenario, create, modify, and redirect fi les 109
Text Editors 110
File Readers 114
Output Redirection 117
Text Processing 123
File and Directory Operations 129
Bonus: regex 141
CHAPTER 10 Given a scenario, manage services 143
Systemd Management 144
Systemd-analyze blame 148
Unit Files 148
SysVinit 152
CHAPTER 11 Summarize and explain server roles 157
NTP 158
SSH 158
Web 159
Certificate Authority 159
Name Server 159
DHCP 160
CHAPTER 12 Given a scenario, automate and schedule jobs 165
cron 165
at 165
crontab 167
fg 170
bg 171
& 171
kill 171
Ctrl-c 172
Ctrl-z 172
nohup 172
CHAPTER 13 Explain the use and operation of Linux devices 173
Types of Devices 174
Monitoring and Configuration Tools 176
File Locations 182
Hot Pluggable Devices 185
CHAPTER 14 Compare and Contrast Linux Graphical User Interfaces 187
Servers 187
GUI 188
Remote Desktop 189
Accessibility 192

Part III: Security
CHAPTER 15 Given a scenario, apply or acquire the appropriate user and/or group permissions and ownership 193
File and Directory Permissions 194
Context-Based Permissions 203
Privilege Escalation 209
User Types 211
CHAPTER 16 Given a scenario, confi gure and implement appropriate access and authentication methods 213
PAM 214
SSH 221
TTYs 228
PTYs 230
PKI 230
VPN as a Client 231
Transport Mode 232
Tunnel Mode 232
IPSec 232
DTLS 233
CHAPTER 17 Summarize security best practices in a Linux environment 235
Boot Security 236
Additional Authentication Methods 237
Multifactor Authentication 237
Importance of Disabling Root Login via SSH 239
Password-Less Login 239
Chroot Jail Services 240
No Shared IDs 240
Importance of Denying Hosts 240
Separation of OS Data from Application Data 241
Change Default Ports 241
Importance of Disabling or Uninstalling Unused and Unsecure Services 242
Importance of Enabling SSL/TLS 243
Importance of Enabling auditd 243
CVE Monitoring 243
Discouraging Use of USB Devices 243
Disk Encryption 244
Restrict cron Access 244
Disable Ctrl-Alt-Del 244
Add Banner 245
MOTD 245
CHAPTER 18 Given a scenario, implement logging services 247
Key File Locations 247
Log Management 249
CHAPTER 19 Given a scenario, implement and confi gure Linux fi rewalls 257
Access Control Lists 258
Technologies 259
IP Forwarding 263
Dynamic Rule Sets 263
Common Application 265
CHAPTER 20 Given a scenario, backup, restore, and compress fi les 267
Archive and Restore Utilities 268
Compression 269
Backup Types 272
Off-Site/Off-System Storage 274
Integrity Checks 275

Part IV: Linux Troubleshooting and Diagnostics
CHAPTER 21 Given a scenario, analyze system properties and remediate accordingly 277
Network Monitoring and Configuration 278
Storage Monitoring and Configuration 287
CPU Monitoring and Configuration 289
Memory Monitoring and Configuration 292
Lost Root Password 295
CHAPTER 22 Given a scenario, analyze system processes in order to optimize performance 297
Process Management 297
Process States 297
Priorities 298
Kill Signals 299
Commands 300
PIDs 305
CHAPTER 23 Given a scenario, analyze and troubleshoot user issues 307
Permissions 307
Access 309
Authentication 309
File Creation 310
Insufficient Privileges for Authorization 312
Environment and Shell Issues 312
CHAPTER 24 Given a scenario, analyze and troubleshoot application and hardware issues 313
SELinux Context Violations 314
Storage 314
Firewall 317
Permission 318
Service Accounts 319
Group Memberships 319
Dependencies 319
Troubleshooting Additional Hardware Issues 320

Part V: Automation and Scripting
CHAPTER 25 Given a scenario, deploy and execute basic BASH scripts 327
Shell Environments and Shell Variables 328
#!/ bin/bash 332
Sourcing Scripts 332
Directory and File Permissions 333
Extensions 333
Commenting 333
File Globbing 334
Shell Expansions 334
Redirection and Piping 336
Exit Codes 336
Metacharacters 336
Positional Parameters 337
Looping Constructs 337
Conditional Statements 338
Escaping Characters 340
CHAPTER 26 Given a scenario, carry out version control using Git 343
Arguments 343
Files 349
CHAPTER 27 Summarize orchestration processes and concepts 351
Agent 351
Agentless 352
Procedures 352
Attributes 352
Infrastructure Automation 352
Infrastructure as Code 352
Inventory 353
Automated Configuration Management 353
Build Automation 353

APPENDIX Create your own journal 355

9780135591840, TOC, 7/19/19


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