Home > Store

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

eBook (Watermarked)

  • Your Price: $27.19
  • List Price: $33.99
  • Includes EPUB and PDF
  • About eBook Formats
  • This eBook includes the following formats, accessible from your Account page after purchase:

    ePub EPUB The open industry format known for its reflowable content and usability on supported mobile devices.

    Adobe Reader PDF The popular standard, used most often with the free Acrobat® Reader® software.

    This eBook requires no passwords or activation to read. We customize your eBook by discreetly watermarking it with your name, making it uniquely yours.

Also available in other formats.

Register your product to gain access to bonus material or receive a coupon.


  • Copyright 2020
  • Pages: 416
  • Edition: 2nd
  • eBook (Watermarked)
  • ISBN-10: 0-13-559193-7
  • ISBN-13: 978-0-13-559193-2

Here are all the Linux commands, files, and concepts you need to pass your CompTIA Linux+ exam, in one concise, condensed resource. CompTIA Linux+ Portable Command Guide, Second Edition, is filled with valuable, easy-to-access information–and it’s portable enough to use wherever your work takes you.
This guide summarizes all Linux+ certification-level Linux commands, keywords, command arguments, and associated prompts, and provides tips and examples of how to apply them to real-world scenarios. Configuration examples throughout the book give you a better understanding of how these commands are used in real-world environments.
Fully updated for today’s CompTIA XK0-004 exam, this quick reference resource will help you memorize commands and concepts as you work to earn your Linux+ certification and use it in the workplace.Linux+ commands for research and solutions

  • Logical how-to topic groupings for a one-stop resource
  • Great for review before your Linux+ certification exam
  • Compact size makes it easy to carry with you, wherever you go
  • “Create Your Own Journal” appendix with blank, lined pages lets you personalize the book for your needs
  • “What Do You Want to Do?” chart inside front cover helps you to quickly reference specific tasks

The book is organized into these parts:
  • Part I: Hardware and System Configuration: boot process, kernel modules, network connections, storage, cloud, virtualization, localization
  • Part II: Systems Operation and Maintenance: software installation/configuration, users/groups, services, server roles, jobs, Linux devices, GUIs
  •  Part III: Security: user/group permissions and ownership, access/authentication, security best practices, logging, firewalls, backup/restore/compress
  • Part IV: Linux Troubleshooting and Diagnostics: analyze/remediate system properties; optimize performance; troubleshoot user, application, and hardware issues
  • Part V: Automation and Scripting: BASH scripting, Git version control, orchestration

Sample Content

Sample Pages

Download the sample pages (includes Chapter 15)

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
    SSL/TLS 232
    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


Submit Errata

More Information

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020