010-160 Exam Dumps - Linux Essentials Certificate Exam - version 1.6

RPM stands for RPM Package Manager (formerly known as Red Hat Package Manager), which is a powerful, command-line package management tool developed for the Red Hat operating system. It is now used as a core component in many Linux distributions such as CentOS, Fedora, Oracle Linux, openSUSE and Mageia1. RPM can install, uninstall,and query individual software packages, but it cannot manage dependency resolution like YUM2. YUM is another package management tool that is based on RPM and can handle dependencies automatically. YUM is the primary package management tool for installing, updating, removing, and managing software packages in Red Hat Enterprise Linux2. Therefore, the correct answer is B. rpm, as it is the underlying package management tool used in Red Hat-based Linux systems. References:

• Linux package management with YUM and RPM | Enable Sysadmin
• Chapter 13. Package Management Tool Red Hat Enterprise Linux 5 | Red Hat Customer Portal
• Difference Between YUM and RPM | 2DayGeek

When a user account is deleted, the files owned by that user are not automatically deleted from the file system, unless they are in the user’s home directory. The files residing outside the home directory will remain unchanged, but they will have an invalid owner. The owner of a file is identified by a numeric user ID (UID), which is mapped to a user name by the /etc/passwd file. When a user is deleted, the corresponding entry in the /etc/passwd file is removed, but the UID of the file is not changed. Therefore, when listing the file’s details, the UID of the former owner is shown instead of the user name. For example, if the user alice with UID 1001 is deleted, and she owns a file named report.txt in the /tmp directory, the output of ls -l /tmp/report.txt will look something like this:

-rw-r–r-- 1 1001 users 1024 Nov 20 14:11 /tmp/report.txt

The user root is not set as the new owner of the file, nor is the file moved to /lost+found or removed from the file system. The /lost+found directory is used to store files that are recovered from a corrupted file system after running the fsck command, not from deleted user accounts. The file system check does not affect the ownership or permissions of the files, unless there is a serious inconsistency that needs to be fixed. References:

• Linux Essentials - Linux Professional Institute (LPI), section 5.2.1
• 5.2 Lesson 1 - Linux Professional Institute Certification Programs, slide 6.

The sort command is used to sort the lines of a file or a stream of input according to a specified criterion, such as alphabetical order, numerical order, reverse order, etc. By default, the sort command sorts the lines in ascending alphabetical order, using the firstcharacter of each line as the key. For example, the command sort data.csv will sort the lines of the file data.csv in alphabetical order and display the output on the screen. If you want to save the sorted output to a new file, you can use the redirection operator (>) to specify the output file name. For example, the command sort data.csv > sorted_data.csv will sort the lines of the file data.csv in alphabetical order and save the output to a new file named sorted_data.csv. The other commands are either invalid or do not perform the sorting operation. The a…z command does not exist, the abc command is a text editor, the wc command counts the number of words, lines, and bytes in a file, and the grep command searches for a pattern in a file or a stream of input. Therefore, the correct answer is B. References:

• Linux Essentials - Linux Professional Institute (LPI), section 2.3.2
• LPI Linux Essentials Study Guide: Exam 010 v1.6, 3rd Edition, chapter 4, page 95.

 A typical shell script is a text file that contains a series of commands or instructions that can be executed by a shell interpreter. A shell script usually has the executable permission bit set, which means that it can be run as a program by the user or another program. A shell script also starts with the two character sequence #!, which is called a shebang or a hashbang. This sequence tells the operating system which shell interpreter to use to run the script. For example, #!/bin/bash indicates that the script should be run by the bash shell. References:

• Linux Essentials - Linux Professional Institute (LPI) 1
• Linux Essentials - Linux Professional Institute Certification Programs 2

CentOS is a Linux distribution that is based on the source code of Red Hat Enterprise Linux (RHEL). It is a free and open-source community-supported OS that provides an enterprise-level computing platform. CentOS is fully compatible with RHEL and can run the same applications and packages. Therefore, CentOS allows the team members to apply as much of their Red Hat Enterprise Linux knowledge as possible for their hobby project. References:

• Linux Essentials Version 1.6 Objectives1, Topic 1.1: Linux Evolution and Popular Operating Systems, Subtopic: Linux Distributions
• Linux Essentials Version 1.6 Exam Preparation Guide2, Section 1.1: Linux Evolution and Popular Operating Systems, Page 7
• CentOS Website3, About CentOS Linux
• Red Hat Enterprise Linux derivatives - Wikipedia4

The passwd command in Linux is used to change the password of a user account. A normal user can run passwd to change their own password, and a system administrator (the superuser) can use passwd to change another user’s password, or define how that account’s password can beused or changed1. The passwd command can also be used to lock or unlock a user account. Locking a user account means disabling the user’s ability to log in to the system, while unlocking a user account means restoring the user’s ability to log in. To lock a user account, the passwd command can be used with the -l option, followed by the username. To unlock a user account, the passwd command can be used with the -u option, followed by the username12. The passwd command cannot be used to change a user’s username, create a new user account, or create a new user group. These tasks require different commands, such as usermod, useradd, orgroupadd345. References: 1: Linux Passwd Command Help and Examples 2: Passwd command in Linux: 8 Practical Examples 3: usermod(8) - Linux man page 4: useradd(8) - Linux man page 5: groupadd(8) - Linux man page

These are the three most common service models offered by public cloud providers12. They differ in the level of abstraction and control they provide to the customers.

• Platform as a Service (PaaS) is a service model where the public cloud provider offers a ready-to-use platform for developing, testing, and deploying applications. The provider manages the underlying infrastructure, such as servers, storage, network, and operating system, while the customer only needs to focus on the application code andconfiguration. Examples of PaaS include Google App Engine, IBM Cloud Foundry, and Microsoft Azure App Service12.
• Infrastructure as a Service (IaaS) is a service model where the public cloud provider offers access to fundamental compute, network, and storage resources on demand over the public Internet or through dedicated connections. The provider manages the physical hardware and virtualization layer, while the customer has full control over the configuration and management of the virtual machines, operating system, and applications. Examples of IaaS include Google Compute Engine, IBM Cloud Virtual Servers, and Microsoft Azure Virtual Machines12.
• Software as a Service (SaaS) is a service model where the public cloud provider offers ready-to-use software applications that run on the provider’s infrastructure and are accessible through a web browser or a mobile app. The provider manages the entire software stack, including the infrastructure, platform, and application, while the customer only needs to pay for the usage or subscription of the service. Examples of SaaS include Google Workspace, IBM Watson, and Microsoft Office 36512.

References:

• What is Public Cloud | IBM
• What Is a Public Cloud? | Google Cloud

The general structure of a for loop in a shell script is as follows12:

for variable in list do commands done

The variable is the name of a loop counter or iterator that takes on the values of the items in the list. The list can be a sequence of words, numbers, filenames, or the output of a command. The commands are the body of the loop that are executed for each value of the variable. The do and done keywords mark the beginning and the end of the loop body.

The option C. for file in *.txt do echo $i done follows this structure, with the variable being file, the list being *.txt (which matches all the files with the .txt extension in the current directory), and the command being echo $i (which prints the value of the variable i, which is presumably set somewhere else in the script).

The other options are incorrect because:

• A. for *.txt as file => echo $file uses an invalid syntax for a for loop. The as keyword is not part of the shell script syntax, and the => symbol is not a valid operator. The correct way to write this loop would be:

for file in *.txt do echo $file done

• B. for *.txt ( echo $i ) uses an invalid syntax for a for loop. The parentheses are not part of the shell script syntax, and the loop body is missing the do and done keywords. The correct way to write this loop would be:

for i in *.txt do echo $i done

• D. for ls *.txt exec {} ; uses an invalid syntax for a for loop. The ls command is not a valid variable name, and the exec {} ; is not a valid command. This looks like a mix of a for loop and a find command. The correct way to write this loop would be:

for file in *.txt do exec $file done

• E. foreach @{file} { echo $i } uses an invalid syntax for a for loop. The foreach keyword is not part of the shell script syntax, and the @{file} and { echo $i } are not valid expressions. This looks like a mix of a for loop and a Perl syntax. The correct way to write this loop would be:

for file in * do echo $file done

References:

• Looping Statements | Shell Script - GeeksforGeeks
• How do I write a ‘for’ loop in Bash? - Stack Overflow

The last command in Linux is used to display the list of all the users logged in and out since the file /var/log/wtmp was created1. The output of the last command shows the username, the terminal, the IP address, the login time and date, and the duration of the session for each record2. The option E is the only one that matches this format. Theother options are not related to the last command. Option A shows a list of commands executed by a user. Option B shows the password change information for a user. Option C shows the last login information for a user. Option D shows the mount information for a filesystem. References:

• Linux Essentials Version 1.6 Objectives3, Topic 1.4: Command Line Basics, Subtopic: Basic Shell Commands
• Linux last Command Tutorial for Beginners (8 Examples)4
• Linux Essentials Version 1.6 Exam Preparation Guide, Section 1.4: Command Line Basics, Page 16

 The dmesg command is used to display the messages from the kernel that are stored in a ring buffer. A ring buffer is a fixed-size data structure that overwrites the oldest entries when it is full. Therefore, the dmesg command might not display older information because it was overwritten by newer information. The dmesg command is useful for troubleshooting system issues and checking hardware information. The dmesg command is not used to trace the execution of a command, send messages to user sessions, or output the system journal. Those functions are performed by other commands such as strace, write, and journalctl respectively. References: : [dmesg] : [Ring buffer] : [strace] : [write (Unix)] : [journalctl]4)

The host command is used to resolve a DNS name to an IP address or vice versa. It can also perform other DNS queries, such as finding the mail servers for a domain. The host command has the following syntax: host [options] [name] [server]. The name argument can be a hostname, such as www.lpi.org, or an IP address, such as 192.168.0.1. The server argument is optional and specifies the name or IP address of the DNS server to query. If no server is given, the default system resolver is used.  References:

• Linux Essentials Version 1.6 Objectives: 1.4.1. Demonstrate an understanding of the purpose and types of DNS records1
• Linux Essentials Version 1.6 Exam Study Resources: Linux Essentials Manual - Chapter 10. Network Fundamentals - 10.3. DNS and Hostname Resolution - 10.3.1. The host Command2
• Linux Essentials Version 1.6 Exam Study Resources: Linux Essentials Manual - Appendix A. Answers to the Exercises - Chapter 10. Network Fundamentals - 10.3. DNS and Hostname Resolution - Exercise 10.3.12

 The correct command to copy the contents of the directory /etc/, including all sub-directories, to /root/ is cp -r /etc/* /root. This command uses the cp command, which stands for copy, and is used to copy files and directories on Linux and Unix systems. The command also uses the following options and arguments123:

• The -r option, which stands for recursive, and tells cp to copy all files and sub-directories of the source directory. Alternatively, the -R option can be used, which has the same effect as -r.
• The /etc/* argument, which specifies the source directory and all its contents. The asterisk (*) is a wildcard character that matches any file or directory name. This argument tells cp to copy everything inside the /etc/ directory, but not the directory itself.
• The /root argument, which specifies the destination directory. This argument tells cp to copy the source files and sub-directories to the /root/ directory.

The other options are incorrect because they use different commands or syntax that do not copy the contents of the directory /etc/, including all sub-directories, to /root/. For example:

• Option A uses the copy command, which is not a valid Linux command. The correct command is cp.
• Option C uses the -v option, which stands for verbose, and tells cp to print verbose output. This option does not affect the copying process, but only the output. It also does not include the -r or -R option, which is necessary to copy the sub-directories.
• Option D uses the rcp command, which stands for remote copy, and is used to copy files between different hosts on a network. This command is not relevant for copying files on the same host.
• Option E uses the -R option, which is correct, but also uses the . argument, which is incorrect. The dot (.) is a special character that matches any single character. This argument tells cp to copy only the files and directories that have a dot in their name, which may exclude some files and directories that do not have a dot.

References: 1: Cp Command in Linux (Copy Files) | Linuxize 2: cp command in Linux with examples - GeeksforGeeks 3: How to Copy Files and Directories in the Linux Terminal

 CentOS is a Linux distribution that is derived from Red Hat Enterprise Linux (RHEL). CentOS stands for Community Enterprise Operating System and it aims to provide a free, enterprise-class, community-supported computing platform that is functionally compatible with RHEL. CentOS is one of the most popular Linux distributions for servers and cloud computing. Raspbian, openSUSE, Debian and Ubuntu are other Linux distributions that are not derived from RHEL, but have their own origins and development histories. Raspbian is based on Debian and optimized for the Raspberry Pi. openSUSE is a community project sponsored by SUSE Linux and other companies. Debian is one of the oldest and most influential Linux distributions, and Ubuntu is derived from Debian and sponsored by Canonical Ltd. References:

• Linux Essentials - Linux Professional Institute (LPI) 1
• Linux Essentials Version 1.6 Update - Linux Professional Institute (LPI) 2
• Free LPI 010-160 Questions - Pass LPI 010-160 - Pass4Success 3
• LPI Linux Essentials Study Guide: Exam 010 v1.6, 3rd Edition 4

Linux passwords are not stored in plain text, but in a scrambled or encrypted form known as a hash. A hash is a one-way function that transforms a string of characters into a fixed-length value. The same input always produces the same hash, but it is impossible to reverse the process and recover the original input from the hash. This way, the system can verify the user’s password without exposing it to anyone who can read the file where the hashes are stored. The file that contains the password hashes is /etc/shadow, which is only readable by the root user or members of the shadow group. The passwd utility is used to change the user’s password, which updates the hash in the /etc/shadow file. References: Linux Essentials 1.6 Topic 105: Security and File Permissions, How to Change Account Passwords on Linux, Where is my password stored on Linux?

To remove a directory, you need to use a command that can delete directories, not just files. The rm command can only remove files by default, unless you use the -r option, which stands for recursive. This option tells rm to delete the directory and all of its contents, including subdirectories and files. The rmdir command can also remove directories, but only if they are empty. If the directory contains any files or subdirectories, rmdir will fail and display an error message. Therefore, the correct commands to remove Downloads, assuming it is empty, are rmdir Downloads and rm -r Downloads. The other commands are either invalid or do not work on directories. References:

• Linux Essentials - Linux Professional Institute (LPI), section 2.3.1
• LPI Linux Essentials Study Guide: Exam 010 v1.6, 3rd Edition, chapter 4, page 93.

The backslash character () is used to escape the meaning of the next character in a command line. This means that the next character is treated as a literal character, not as a special character. For example, if you want to use a space in a file name, you can use a backslash before the space to prevent the shell from interpreting it as a separator. Similarly, if you want to split a long command line across multiple lines, you can use a backslash at the end of each line to tell the shell that the command is not finished yet. The shell will ignore the newline character and continue reading the next line as part of the same command. For example, you can write:

ls -l/home/user/Documents

instead of:

ls -l /home/user/Documents

Both commands will produce the same output, but the first one is easier to read and type. References:

• Linux Essentials - Linux Professional Institute (LPI), section 2.1.2
• 2.1 Command Line Basics - Linux Professional Institute Certification Programs, slide 7.

 Reverse DNS lookups query DNS servers for a PTR (pointer) record; if the server does not have a PTR record, it cannot resolve a reverse lookup. PTR records store IP addresses with their segments reversed, and they append “.in-addr.arpa” to that. For example, if a domain has an IP address of 192.0.2.1, the PTR record will store the domain’s information under 1.2.0.192.in-addr.arpa. In IPv6, the latest version of the Internet Protocol, PTR records are stored within the “.ip6.arpa” domain instead of ".in-addr.arpa."1 Therefore, the name of the IP address 198.51.100.165 is stored in the PTR record for 165.100.51.198.in-addr.arpa. References: 1: Reverse DNS lookup - Wikipedia 1

A vector graphics editor is a software program that allows users to create and edit vector graphics, which are images composed of mathematical curves and shapes. Vector graphics are scalable, meaning they can be resized without losing quality or clarity. Python, NGINX, Samba, and MySQL are not vector graphics editors, but rather other types of software. Python is a programming language, NGINX is a web server, Samba is a file and print server, and MySQL is a database management system. Inkscape is a free and open source vector graphics editor that supports the SVG (Scalable Vector Graphics) format, as well as other formats. Inkscape can be used to create logos, icons, diagrams, illustrations, and other graphics. Inkscape is one of the applications covered in the Linux Essentials certification program from the Linux Professional Institute (LPI). References:

• Linux Essentials - Linux Professional Institute (LPI)
• Draw Freely | Inkscape

The /etc/skel directory is a skeleton directory that contains the default files and directories that are automatically copied to the home directory of a new user when the account is created by the useradd command12. The purpose of this directory is to provide a consistent and uniform environment for all new users and to save the system administrator’s time and effort in configuring the user settings12. The /etc/skel directory can be customized by adding or removing files and directories as needed, depending on the desired default settings for the new users12.

The other options are incorrect because:

• A. The personal user settings of root are stored in this directory. This is not true, as the personal user settings of root are stored in the /root directory, which is the home directory of the root user3. The /etc/skel directory does not affect the root user’s settings, but only the settings of the new users created by the useradd command12.
• B. The files from the directory are copied to the home directory of the new user when starting the system. This is not true, as the files from the directory are copied to the home directory of the new user when the account is created, not when starting the system12. The copying process only happens once, when the useradd command is executed, and not every time the system is started12.
• E. The directory contains the global settings for the Linux system. This is not true, as the directory contains the default settings for the new users, not the global settings for theLinux system12. The global settings for the Linux system are usually stored in other directories under /etc, such as /etc/default, /etc/sysconfig, /etc/init.d, etc4.

References:

• Understanding the /etc/skel directory in Linux – The Geek Diary
• /etc/skel directory in Linux - techPiezo
• Linux File System Hierarchy - /root directory - LinuxConfig.org
• Linux configuration: Understanding *.d directories in /etc | Enable Sysadmin

A process ID on Linux is a unique integer value that identifies a running process. The process ID can range from 0 to a maximum limit, which is usually 32768 or higher, depending on the system configuration. The process ID of 0 is reserved for the kernel’s idle task, and the process ID of 1 is reserved for the init system, which is the first process launched by the kernel. The process IDs are assigned sequentially to new processes, and are recycled when a process terminates. Therefore, the only valid value for a process ID among the given options is 21398, which is an integer within the possible range. The other values are not valid process IDs because they are either strings, hexadecimal numbers, or file paths, which do not match the format of a process ID on Linux. References:

• Linux Essentials - Linux Professional Institute (LPI)
• How Are Linux PIDs Generated? | Baeldung on Linux

The command pwd stands for “print working directory”. It will print the absolute path of the current working directory to the terminal. For example, if we are currently in the /home/user/directory, it will print out that exact path1. The pwd command is useful for finding out where we are in the file system hierarchy and for verifying the location of files and directories2.

The other options are not commands that show the absolute path to the current working directory. The who command shows the users who are currently logged in to the system3. The cd … command changes the current working directory to the parent directory of the current one2. The ls -l command lists the files and directories in the current working directory in a long format, which shows the permissions, ownership, size, date, and name of each file and directory2. The cd ~/home command changes the current working directory to the /home directory under the user’s home directory, which may or may not exist2. References:

• Linux Essentials Exam Objectives, Version 1.6, Topic 103.1, Weight 2
• Linux Essentials Certification Guide, Chapter 3, Page 51-52
• How to Get the current directory in Linux - howtouselinux
• How To Find The Absolute Path Of A File Or Directory In Linux - systranbox