Top Tips for Passing the LPI 101-500 Exam on Your First Try

The Linux root partition is the partition that contains the root filesystem, which is the top-level directory of the filesystem hierarchy. The root filesystem contains the essential files and directories that are needed to boot the system, such as the kernel, the init system, the configuration files, the libraries, the binaries, and the device files. The root partition can be formatted with different filesystems, depending on the support of the kernel and the boot loader. Some of the common filesystems that can be used on Linux root partitions are:

• ext3: This is the third extended filesystem, which is a journaling filesystem that provides metadata and data integrity, fast recovery, and backward compatibility with ext2. ext3 is widely supported by most Linux distributions and boot loaders, and it is considered stable and reliable. ext3 has been the default filesystem for many Linux distributions, such as Debian, Ubuntu, Fedora, and CentOS, until it was replaced by ext4.
• XFS: This is a high-performance 64-bit journaling filesystem that supports large files and volumes, parallel I/O, extent-based allocation, and online defragmentation. XFS is designed for scalability and efficiency, and it is suitable for applications that handle large amounts of data, such as databases, video editing, and data warehousing. XFS is the default filesystem for Red Hat Enterprise Linux and SUSE Linux Enterprise Server, and it is also supported by other Linux distributions and boot loaders.

The other options are not valid filesystems for Linux root partitions, because:

• NTFS: This is the New Technology File System, which is the default filesystem for Windows operating systems. NTFS supports features such as journaling, encryption, compression, and access control. NTFS is not natively supported by the Linux kernel, and it requires a third-party driver, such as ntfs-3g, to read and write to NTFS partitions. NTFS is not compatible with the Linux boot loader, and it cannot be used as the root filesystem for Linux.
• VFAT: This is the Virtual File Allocation Table, which is an extension of the FAT32 filesystem that supports long file names. VFAT is a legacy filesystem that is mainly used for compatibility with older Windows and DOS systems. VFAT does not support features such as journaling, permissions, and symbolic links, and it has limitations on the file and volume size. VFAT is not suitable for the root filesystem for Linux, and it is not supported by the Linux boot loader.
• swap: This is not a filesystem, but a special type of partition that is used to store the memory pages that are not currently in use by the system. swap is used to extend the physical memory of the system, and it can improve the performance and stability of the system. swap is not a mountable partition, and it cannot be used as the root filesystem for Linux.

References:

• Linux Filesystems Explained — ext2/3/4, XFS, Btrfs, ZFS
• Linux File Systems: Ext2 vs Ext3 vs Ext4
• What is a Linux SWAP Partition and Why is it Important?

The correct option to pass to a filesystem’s entry in /etc/fstab in order to mount the file system without root privileges is:

D. user

The /etc/fstab file is a configuration file that contains information about the filesystems on a Linux system. The /etc/fstab file defines how and when the filesystems are mounted by the mount command or the system. The /etc/fstab file has six fields for each filesystem entry, separated by whitespace. The fields are:

• device: the device name or the UUID of the filesystem
• mountpoint: the directory where the filesystem is mounted
• type: the filesystem type, such as ext4, xfs, vfat, etc.
• options: the mount options that modify the behavior of the mount operation, such as ro, noauto, user, etc.
• dump: a flag that indicates whether the filesystem should be backed up by the dump command, 0 for no and 1 for yes
• pass: a flag that indicates the order of filesystem checks by the fsck command at boot time, 0 for no check, 1 for root filesystem, and 2 or higher for other filesystems

The user option is a mount option that allows any non-root user to mount the filesystem. By default, only the root user can mount filesystems, unless they are specified in the /etc/fstab file with the user option. For example, to allow any user to mount a USB drive with the device name /dev/sdb1 to the directory /mnt/usb, the /etc/fstab entry would look like:

/dev/sdb1 /mnt/usb vfat user 0 0

The user option also implies the noexec, nosuid, and nodev options, which prevent the execution of binaries, the setuid and setgid bits, and the device files on the mounted filesystem, respectively. These options can be overridden by using the exec, suid, and dev options after the user option.

The other options are not correct because:

• A. auto: This option indicates that the filesystem should be mounted automatically by the mount -a command or at boot time. This option does not affect the ability of non-root users to mount the filesystem. By default, all filesystems in the /etc/fstab file have the auto option, unless they are explicitly marked with the noauto option.
• B. norestrict: This option does not exist in the mount command or the /etc/fstab file. There is no such option as norestrict in the Linux documentation or the man pages.
• C. noauto: This option indicates that the filesystem should not be mounted automatically by the mount -a command or at boot time. This option does not affect the ability of non-root users to mount the filesystem. The noauto option is usually used for removable devices or network shares that are only mounted on demand.

The mkfs command creates a file system on a given device partition. If the type of file system is not specified, the default file system type is ext2. This is mentioned in the man page of mkfs1 and also in the article by How-To Geek2. Ext2 is an older file system that does not support journaling, which is a feature that allows the file system to recover from crashes or power failures. Ext2 is not very commonly used nowadays, as most Linux systems prefer ext4 or other file systems that support journaling and other features. References:

• How to Use the mkfs Command on Linux - How-To Geek
• mkfs(8): build file system - Linux man page

The command rpm -qpl apache-ql.rpm is used to preview the list of files that would be installed by the RPM package file apache-xml.rpm. This command queries the package file without installing it and lists the contents of the package. Here’s what each part of the command means:

• rpm is the command-line tool used for managing RPM packages on Linux systems.
• -qpl are options for the rpm command.
• apache-xml.rpm is the name of the RPM package file you want to query.

So, when you run this command, it will display a list of all the files that are included in the apache-xml.rpm package file, without installing it. This can be useful for checking what files are included in the package before installing it or comparing it with another version of the package.

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

• rpm -qp apache-xml.rpm will only display the name and version of the package, not the list of files.
• rpm -qv apache-xml.rpm will display the verbose information about the package, such as the description, license, and changelog, but not the list of files.
• rpm -ql apache-xml.rpm will list the files that are installed on the system by the apache-xml.rpm package, but only if the package is already installed. If the package is not installed, it will return an error.

References:

• 4 ways to list files within a rpm package in Linux
• How to list all files installed by RPM package
• How to List Files Installed From an RPM Package in CentOS?
• How to list all files contained in an RPM package

The correct permissions and ownership for the file /etc/passwd are:

B. -rw-r–r-- 1 root root 531 Jun 5 22:45 /etc/passwd

The /etc/passwd file is a plain text-based database that contains information for all user accounts on the system. It is owned by root and has 644 permissions. The file can only be modified by root or users with sudo privileges and readable by all system users. The permissions and ownership of the file are important for the security and functionality of the system. The permissions and ownership of the file can be viewed by using the ls -l command. For example:

ls -l /etc/passwd

The output of the command will show the following information:

-rw-r–r-- 1 root root 531 Jun 5 22:45 /etc/passwd

The first column shows the permissions of the file, which are composed of 10 characters. The first character indicates the file type, which is - for regular files. The next nine characters indicate the permissions for the user (owner), the group, and the others, respectively. Each set of three characters indicates the read ®, write (w), and execute (x) permissions. A dash (-) means no permission. In this case, the permissions are:

• rw- for the user, which means the user can read and write the file, but not execute it.
• r-- for the group, which means the group can only read the file, but not write or execute it.
• r-- for the others, which means the others can only read the file, but not write or execute it.

The second and third columns show the owner and the group of the file, which are both root. The root user is the superuser or the administrator of the system, who has full access and control over the system. The root group is the primary group of the root user, which usually has no other members.

The fourth column shows the size of the file in bytes, which is 531 in this case. The fifth and sixth columns show the date and time of the last modification of the file, which are Jun 5 22:45 in this case. The last column shows the name of the file, which is /etc/passwd in this case.

The other options are not correct because:

• A. -rw------- 1 root root 531 Jun 5 22:45 /etc/passwd: This option has the wrong permissions for the file. The permissions are 600, which means only the user (root) can read and write the file, and the group and the others have no permissions at all. This would prevent the system users from reading the file, which would cause problems for the login process and other utilities that rely on the file.
• C. -rw-r–r-- 1 1 531 Jun 5 22:45 /etc/passwd: This option has the wrong owner and group for the file. The owner and group are both 1, which is the numeric ID of the user and group. However, the numeric ID of the root user and group is 0, not 1. The user and group with the numeric ID of 1 are usually bin, which is a system user and group that own some system binaries and directories. Thebin user and group should not own the /etc/passwd file, as this would compromise the security and functionality of the system.
• D. -rw------- 1 1 531 Jun 5 22:45 /etc/passwd: This option has both the wrong permissions and the wrong owner and group for the file. The permissions are 600, which means only the user can read and write the file, and the owner and group are both 1, which is the numeric ID of the bin user and group. This would prevent the system users from reading the file, and give the bin user and group full access to the file, which would cause problems for the security and functionality of the system.

PWD”,C.pwd∗∗ComprehensiveExplanation:∗∗ThecommandsthatwillprintthecurrentworkingdirectorywhenusingaBashshellareecho“{PWD}” and pwd. The echo command will print the value of the PWD variable, which is set by the shell to the current working directory. The pwd command will print the name of the current working directory. The WD variable is not a standard shell variable and may not be defined. The printwd command is not a valid Linux command. The pwd variable is not the same as the PWD variable and may not be defined.References:LPI Exam 101 Detailed Objectives, Topic 103: GNU and Unix Commands, Weight: 25, Objective 103.1: Work on the command line, echo command, pwd command

The modes of the vi editor that are correct are insert mode and command mode. The vi editor is a modal editor, which means that it has different modes for different operations. The insert mode allows the user to insert text into the file. The command mode allows the user to execute commands, such as saving, quitting,moving the cursor, searching, replacing, and so on. The user can switch between the modes by pressing certain keys, such as Esc, i, a, o, and others. The edit mode, change mode, and review mode are not valid modes of the vi editor. References: LPI Exam 101 Detailed Objectives, Topic 103: GNU and Unix Commands, Weight: 25, Objective 103.8: Use vi to create and edit files, vi editor

The rpm command is used to install, upgrade, query, verify and remove RPM packages on Linux systems. The -U option is used to upgrade an existing package to a newer version, or install a package if it does not exist in the RPM database. The -U option is equivalent to -e (erase) followed by -i (install). The other options are not valid for upgrading a package. The -q option is for querying a package, the -e option is for erasing a package, the --force option is for overriding conflicts, and the -u option is not a valid option for the rpm command. References: Using RPM Command to Install, Upgrade and Remove Packages, Linux package management with YUM and RPM

SysVinit is a program for Linux and Unix-based systems that initializes the system and spawns all other processes. It runs as a daemon and has PID 1. The boot loader starts the kernel and the kernel starts SysVinit. A Linux or Unix based system can be started up into various runlevels, which are modes of operation that define what services and processes are running. The /etc/inittab file is the configuration file for SysVinit, which defines the default runlevel, the available runlevels, and the actions to be taken when entering or leaving a runlevel.

The telinit command is used to change the current runlevel of the system or to send a signal to SysVinit. The telinit command takes a single argument, which can be either a runlevel number (0-6) or a special character. The syntax of the telinit command is:

telinit [runlevel|character]

The runlevel argument instructs SysVinit to switch to the specified runlevel. For example, to switch to runlevel 3, which is the multi-user mode with networking, use the following command:

telinit 3

The character argument instructs SysVinit to perform a special action. For example, to reboot the system, use the following command:

telinit 6

The q character argument instructs SysVinit to reload its configuration file, /etc/inittab, without changing the current runlevel. This is useful when the /etc/inittab file has been modified and the changes need to be applied. For example, to reload the /etc/inittab file, use the following command:

telinit q

The other options are not correct because:

• A. reinit: This command does not exist in the Linux system. There is no such command as reinit in the Linux documentation or the man pages.
• B. initreload: This command does not exist in the Linux system. There is no such command as initreload in the Linux documentation or the man pages.
• C. telinit 7: This command is not valid because 7 is not a valid runlevel number. The valid runlevel numbers are 0-6, where 0 means halt, 1 means single-user mode, 2 means multi-user mode without networking, 3 means multi-user mode with networking, 4 means user-defined, 5 means graphical mode, and 6 means reboot. If you run this command, you will get an error message saying:

telinit: invalid runlevel: 7

• E. init reinit: This command is not valid because reinit is not a valid argument for the init command. The init command is a synonym for the telinit command, and it takes the same arguments as the telinit command. The valid arguments for the init command are either a runlevel number (0-6) or a special character. If you run this command, you will get an error message saying:

init: invalid runlevel: reinit

References:

• SysVinit - ArchWiki
• telinit(8) - Linux manual page
• Linux Init RunLevels Explained - nixCraft