LPI Updated 101-500 Exam Questions and Answers by paul

 The command apt-cache is used to query information about the available packages on a Debian system. This command can perform various operations on the package cache, such as searching for packages that match a given pattern, showing detailed information about a specific package, displaying the dependencies of a package, and more. The apt-cache command does not require root privileges and does not modify the system state12.

The other commands are either invalid or do not perform the same function as the correct answer. For example:

• apt-get is used to install, update, upgrade, remove, or purge packages on a Debian system. It requires root privileges and modifies the system state13.
• apt-search is not a valid command. The correct syntax to search for packages using the apt command is apt search1 .
• dpkg is a low-level tool that can install, remove, configure, or query information about Debian packages. It operates on individual packages and does not handle dependencies. It requires root privileges to install or remove packages1 .
• dpkg-search is not a valid command. The correct syntax to search for packages using the dpkg command is dpkg -l or dpkg-query -l1 .

References:

• LPI Linux Essentials, Chapter 6: Managing Software, Section 6.2: Debian Package Management
• apt-cache - query the APT cache | Linux Docs
• apt-get - APT package handling utility | Linux Docs
• [apt - command-line interface | Linux Docs]
• [dpkg - Debian package management system | Linux Docs]

 Linux swap spaces are designated as type 82 on MBR (Master Boot Record) partition tables, which are used to store information about the partitions on a hard disk drive. This type code identifies the partition as a Linux swap area, which can be used by the Linux kernel to supplement the system RAM by holding idle memory pages. The mkswap command can be used to initialize a partition of type 82 as a swap partition. Other type codes are used for different purposes, such as 83 for Linux native partitions, 8e for Linux LVM partitions, fd for Linux RAID partitions, and 7 for NTFS partitions. References:

• How to create swap partition in Linux
• Choosing partition types for swap and root and choosing device for bootloader installation
• Creating and Using a Swap Partition
• Swap

The system configuration file named /etc/inittab is commonly used to set the default runlevel. This file contains information about the initialization process of the system, and it defines the default runlevel, the available runlevels, and the actions to be taken when entering or leaving a runlevel. The default runlevel is the mode of operation that the system starts up into, and it determines which services and processes are running. The default runlevel is specified by a line similar to the following in the /etc/inittab file:

id:5:initdefault:

The number after the first colon indicates the default runlevel, which can range from 0 to 6. The meaning of each runlevel is:

• 0 — Halt
• 1 — Single-user text mode
• 2 — Not used (user-definable)
• 3 — Full multi-user text mode
• 4 — Not used (user-definable)
• 5 — Full multi-user graphical mode (with an X-based login screen)
• 6 — Reboot

To change the default runlevel, edit the /etc/inittab file as root and change the number to the desired runlevel. For example, to change the default runlevel to 3, use the following command:

sudo nano /etc/inittab

And change the line to:

id:3:initdefault:

Then save and exit the file. The changes will take effect on the next reboot.

References:

• SysV Init Runlevels - Red Hat Customer Portal
• init - How can I see or change default run level? - Ask Ubuntu

The tr command is used to translate, squeeze, or delete characters from a file or a stream. The -d option is used to delete characters that appear in the first operand. The \r and \n are escape sequences that represent the carriage return and the line feed characters, respectively. The CR-LF pair is the standard line ending for Windows text files, while the LF character is the standard line ending for Linux text files. Therefore, the command tr –d ‘\r’ < userlist.txt > newlist.txt will delete all the CR characters from the userlist.txt file and redirect the output to the newlist.txt file, effectively converting the line endings from Windows to Linux format. The other commands are incorrect because they either use the wrong syntax, the wrong operands, or the wrong redirection. References:

• LPI 101-500 Exam Objectives, Topic 103.7, Weight 4
• LPI Learning Materials, Chapter 3.7, Basic Scripting
• Web Search Results, 1

QUESTIONNO: 54

When in Normal mode invi, which character can be used to begin a reverse search of the text?

A.?

B./

C.F

D.r

Answer: A

 In vi, the ? character can be used to begin a reverse search of the text. This means that the search will start from the current cursor position and move backwards towards the beginning of the file. The search pattern can be any regular expression that matches the desired text. To repeat the search, the user can press n for the previous match or N for the next match. The / character can be used to begin a forward search of the text, which means that the search will start from the current cursor position and move forwards towards the end of the file. The F and r characters are not used for searching, but for other commands in vi. The F command is used to move the cursor to a previous occurrence of a specified character in the current line. The r command is used to replace the character under the cursor with another character. References:

• LPI 101-500 Exam Objectives, Topic 103.8, Weight 4
• LPI Learning Materials, Chapter 3.8, Advanced Scripting
• Web Search Results,