LPI 702-100 Dumps

The adduser.conf file is used to store the default settings for the interactive adduser script on BSD systems. The adduser script is a shell script that uses the pw command to add new users to the system. It creates passwd/group entries, a home directory, copies dotfiles and sends the new user a welcome message. The adduser.conf file allows the administrator to pre-set certain configuration options, such as the default shell, home partition, login group, encryption method, etc. The other options are either invalid files or belong to other purposes. For example, login.conf is used to define login classes, pw.conf is used to configure the pw command, user.conf is used to set user-specific kernel variables, and usermgmt.conf is used to configure user management utilities. References:

• adduser - FreeBSD adduser(8) Manual Page1
• adduser.conf - FreeBSD adduser.conf(5) Manual Page2
• [pw] - FreeBSD pw(8) Manual Page

The symbol / is used in the vi editor to start the forward search for a string. It is followed by the string to be searched and then Enter to execute the search. The vi editor highlights the first occurrence of the string after the cursor position. To find the next occurrence of the string in the same direction, press n. To find the previous occurrence of the string in the opposite direction, press N. References:

• How to Search to Find a Word in Vim or Vi Text Editor
• How can I switch from forward to backward search in Vim?
• How To Search in VI Editor
• How to Search in Vim / Vi

Compiling an application from source code allows for customization of the binary to a system’s particular needs, including optimization for specific hardware and enabling or disabling certain features. Pre-compiled binaries are quick and easy to install but they don’t allow for such customization.

References:

• Understand the difference between a pre-compiled binary and compiling from source

Permissions involve read, write, and execute roles that can be assigned to the owner, a group, or other users1.To use the chmod command, you must specify the permission you want to set and the file or directory you want to modify1.For example,chmod +rwx filenameto add permissions,chmod -rwx directorynameto remove permissions, orchmod +x filenameto allow executable permissions2.

There are two ways to specify the permissions with the chmod command: symbolic notation and numeric notation1.Symbolic notation uses letters and symbols to represent the user classes and the permissions1.Numeric notation uses octal numbers (0-7) to represent the permissions for each user class1.Each octal digit corresponds to a combination of read ®, write (w), and execute (x) permissions, as shown in the table below3:

Octal digit

Binary representation

Permissions

0

000

—

1

001

–x

2

010

-w-

3

011

-wx

4

100

r–

5

101

r-x

6

110

rw-

7

111

rwx

To use numeric notation, you need to provide three octal digits, one for each user class (owner, group, and others)1.For example,chmod 644 filenamemeans that the owner has read and write permissions (6), the group has read permissions (4), and others have read permissions (4)1.

In this question, the desired permission for the file text.txt is 750, which means that the owner has read, write, and execute permissions (7), the group has read and execute permissions (5), and others have no permissions (0)1. Therefore, the correct chmod command to change the permission of the file text.txt to 750 ischmod text.txt 750.

References:1: Chmod Command in Linux (File Permissions) | Linuxize2: How to change directory permissions in Linux | Pluralsight3: How to Use the chmod Command on Linux - How-To Geek

The umask command in BSD is used to set default permissions for files or directories the user creates1. The umask value is permissions to deny, taken off whatever permissions would be given by default2. The default permission values for files are 666 (rw-rw-rw-), meaning read and write for user, group, and others3. The umask value of 022 means that the permissions to deny are 022 (—w–w-), meaning write for group and others. To calculate the default permissions for newly created files, we need to subtractthe umask value from the default permission value, using bitwise AND operation4. For example:

666 - 022 = 644 rw-rw-rw- - —w–w- = rw-r–r–

Therefore, the default permissions for newly created files with a umask of 022 are 644 (rw-r–r–), meaning read and write for user, and read for group and others.

References: 1: Umask command in Linux with examples - GeeksforGeeks 2: Different permission between directory and file with ‘umask’ - Unix & Linux Stack Exchange 3: Default File Permissions (umask) - docs.oracle.com 4: What is Umask and How to Use It {Update Default Linux File Permissions} - phoenixNAP KB

The swapctl command is used to list, add, or delete swap devices on BSD systems. It can also display the total amount of swap space available and used. The swapctl command takes various options to perform different actions, such as -l to list the swap devices, -a to add a swap device, -d to delete a swap device, and -s to show the swapsummary. The other options are not valid BSD commands for managing swap devices. References:

• swapctl(8) - OpenBSD manual pages
• FreeBSD Handbook - Chapter 19. The FreeBSD Booting Process
• FreeBSD Handbook - Chapter 9. Configuring the FreeBSD Kernel

The question mark (?) is a special character in regular expressions that modifies the preceding expression to match zero or one times. For example, the regular expression colou?r matches both color and colour, but not colouur or colr. The question mark is also used to make an expression non-greedy, meaning that it will match the shortest possible string instead of the longest. For example, the regular expression <.?> matches the first pair of angle brackets in a string, while <.> matches the entire string enclosed by the outermost pair of angle brackets. References:

• Regular expression - Wikipedia, section “Basic concepts”
• How to write Regular Expressions? - GeeksforGeeks, section “Special Characters”

The setenv command is used to set an environment variable in the csh or tcsh shell. The syntax is setenv VAR VALUE, where VAR is the name of the variable and VALUE is the value to assign to it. The TZ variable is used to specify the timezone for the shell and its subprocesses. To set the timezone to GMT (Greenwich Mean Time), the command is setenv TZ GMT. This will affect the output of commands like date and ls that display time information. The other options are either invalid syntax or belong to other shells, such as bash or sh. References:

• setenv - Linux setenv command help and examples1
• TZ - FreeBSD Environment Variables2

The zpool create command is used to initialize ZFS on one or more block devices and create a storage pool. A storage pool is a collection of devices that provide physical storage and data replication for ZFS datasets. The zpool create command takes the name of the pool and the devices to be added as arguments. For example, zpool create mypool c0t0d0 c0t1d0 c0t2d0 would create a pool named mypool with three devices. The other options are either invalid or do not initialize ZFS. References: 1: page 302  2: section “Creating a ZFS Storage Pool”

The groups command is used to show the current user’s group memberships on BSD systems. The command prints the names of the primary and secondary groups that the user belongs to, separated by spaces. The primary group is the one that is assigned to new files and directories created by the user. The secondary groups are the ones that grant additional permissions or access to the user. For example, the output of groups for a user named alice might look like this:

alice wheel staff

This means that alice’s primary group is alice, and her secondary groups are wheel and staff. The wheel group is typically used for granting administrative privileges, such as using the su or sudo commands. The staff group might be used for granting access to certain resources or directories that are shared by a group of users.

The other options are either invalid commands or do not show the user’s group memberships. For example, group is not a valid command, ident is used to query an ident protocol server, showuser is not a valid command, and who is used to show who is logged on the system.

References:

• groups - FreeBSD groups(1) Manual Page1
• Group Management - FreeBSD Handbook2

The command grep "non [-] disclosure" legalfile matches the lines in the file that contain the pattern non [-] disclosure, where the brackets indicate a character class that matches either a space or a dash. Therefore, the lines that contain non-disclosure or non - disclosure are matched by the command, while the line that contains disclosure only is not matched. The file has two lines that contain non-disclosure, so the correct answer is E. non-disclosure and non-disclosure Only. References:

• grep - IBM
• Character Classes and Bracket Expressions - GNU

The find command is used to search for files and directories that match certain criteria. The - -type option specifies the type of file to look for, and the d argument means directories. The . argument means the current directory. Therefore, the command find - -type d searches for all directories within the current directory. The other options are either invalid or do not match the question. References: 1: page 301  2: section “The Linux find Command”

The file /etc/hostname.em0 contains the configuration for the network interface em0 on an OpenBSD system. This file specifies the IP address, netmask, gateway, and other options for the interface. The file is read by the netstart script during boot or when the interface is restarted. The file name is derived from the interface name, which is usually based on the driver name and the device number. For example, em0 is the first interface using the em driver, which supports Intel PRO/1000 network adapters.

References:

• Networking | OpenBSD Handbook
• [hostname.if(5) - OpenBSD manual pages]

The last command displays a list of the last logged in users on a BSD system. The output consists of several columns that show the user name, the terminal name, the login date and time, and the logout date and time or the current status. The option C is the only line that matches the format of the last command output. It shows that the user root logged in on the terminal ttyv0 on Saturday, May 18, 2023 at 13:35 and is still logged in. The other options are either invalid lines or belong to othercommands or sources. For example, option A is the output of the uptime command, option B is a line from the /var/log/auth.log file, option D is a line from the ps command, and option E is the output of the uname -a command. References:

• [last] - FreeBSD last(1) Manual Page
• [How to use the last command in Linux] - Linuxize

The /etc/nsswitch.conf file defines the order of the name resolution methods used on a NetBSD system. It specifies the sources and their priority for various databases, such as hosts, services, protocols, etc. The sources can be files, DNS, NIS, or other services. For example, the following line in /etc/nsswitch.conf indicates that the hosts database should be looked up first in the /etc/hosts file, then in the DNS server, and finally in the NIS server:

hosts: files dns nis

References:

• nsswitch.conf(5) - NetBSD Manual Pages
• Chapter 23. The NetBSD Network Configuration Files

The ports collection on FreeBSD is a package management system that allows users to install third-party software from source or binary packages. The ports collection is stored in the /usr/ports/ directory, which contains subdirectories for different categories of software, such as archivers, databases, editors, etc. Each subdirectory contains one or more ports, which are directories that contain the files needed to build and install the software. The /usr/ports/ directory can be updated with the portsnap command34

Binary packages are pre-compiled versions of the ports that can be installed with the pkg command. Binary packages are downloaded from the FreeBSD package repository,which is hosted at pkg.freebsd.org. The packages are installed in the /usr/local/ directory by default, and the information about the installed packages is stored in the /usr/local/pkg/ directory. The /usr/local/pkg/ directory contains files with the .db extension, which are SQLite databases that store the metadata of the packages. The pkg command can query and manipulate these databases56 References: 3: 4: 5: 6: &sektion=8

The cron job syntax consists of five fields that specify the time and date of execution, followed by the command or script to run. The fields are: minute, hour, day of month, month, and day of week. Each field can have a specific value, a range, a list, a wildcard (), or a step value. The wildcard () means any possible value for that field. The option B sets the minute field to 0 and the hour field to *, which means the script will run at the 0th minute of every hour, regardless of the day, month, or weekday. This is equivalent to once per hour. The other options are either invalid syntax or do not match the desired frequency. For example, option A sets all fields to *, which means the script will run every minute of every hour of every day, month, and weekday. Option C sets the minute field to * and the hour field to 0, which means the script will run every minute of the 0th hour, or once per day at midnight. Option D has a typo (o instead of *) and option E sets the day of month field to o, which is not a valid value. References:

• crontab - FreeBSD crontab(5) Manual Page1
• Crontab Explained in Linux [With Examples] - Linux Handbook2

A symbolic link, or symlink, is a special type of file that points to another file or directory on the file system1. When creating a symbolic link with the ln command, the syntax is as follows:

ln -s target link

where target is the file or directory to link to, and link is the name of the symbolic link2. If the link name already exists, the ln command will fail and display an error message indicating that the target already exists3. This is because the ln command does not overwrite existing files or directories by default4. Therefore, the only way to create a symbolic link with the same name as an existing file or directory is to manually remove the existing target first, and then run the ln command again. Alternatively, the ln command can be used with the -f (force) option, which will remove the existing target and create the symbolic link in one step4. However, this option is not mentioned in the question, so the correct answer is A.

References: 1: How to Create Symbolic Links in Linux [Complete Guide] - Linux Handbook 2: Ln Command in Linux (Create Symbolic Links) | Linuxize 3: How to Create and Use Symbolic Links (aka Symlinks) on Linux - How-To Geek 4: Symbolic Links in Unix/Linux - Stack Abuse