LPIC-1 Practice Exam 3 — 20 Questions

Question 1

An administrator needs to identify the device file for the first SATA SSD in a server. Which device file should they use?

Accepted Answer

/dev/sda. The first SATA SSD in a Linux system is typically assigned the device file /dev/sda. SATA drives use the SCSI subsystem via the libata driver, which names them /dev/sdX, with 'a' representing the first detected drive. This is the standard naming convention for SATA SSDs in modern Linux kernels.

Answer

/dev/hda

Answer

/dev/sdb

Answer

/dev/nvme0n1

Question 2

Refer to the exhibit. A system administrator runs 'ip route show default' and gets this output. What does it indicate?

Accepted Answer

The default route points to gateway 192.168.1.1 on interface eth0.. The command 'ip route show default' displays the default route entry in the kernel routing table. The output shows that the default route (destination 0.0.0.0/0) is via gateway 192.168.1.1 and uses interface eth0, meaning all traffic not matching a more specific route is sent to that gateway on that interface.

Answer

The DNS server is 192.168.1.1.

Answer

The system has no internet access.

Answer

The IP address of the system is 192.168.1.1.

Question 3

A DHCP server assigns IP addresses to clients, but some clients are not receiving the correct gateway. Which configuration file should be checked on the DHCP server?

Accepted Answer

/etc/dhcp/dhcpd.conf. The DHCP server configuration file on Linux systems is typically located at /etc/dhcp/dhcpd.conf (or /etc/dhcpd.conf on some older distributions). This file contains the subnet declarations, option definitions (such as option routers for the default gateway), and other parameters that the DHCP server uses to assign IP addresses and configuration details to clients. If clients are not receiving the correct gateway, the 'option routers' directive within this file should be checked and corrected.

Answer

/etc/dhcpd.conf

Answer

/etc/dhcp/dhclient.conf

Answer

/etc/resolv.conf

Question 4

You are the system administrator for a small business running a Red Hat Enterprise Linux 8 server that hosts a MySQL database and a web server. The server has two physical disks: a 240GB SSD (sda) with partitions sda1 (boot), sda2 (root), sda3 (swap), and a 1TB HDD (sdb) with a single partition sdb1 mounted at /var/lib/mysql. The server has been running for months without issues. However, this morning you receive alerts that the MySQL database is not accepting new connections. You log in and find that the /var filesystem is 100% full. You check the disk usage and see that /var/lib/mysql uses 90% of the space, but there are also large log files in /var/log/httpd. To free up space immediately and restore database service while planning a permanent solution, you decide to compress old log files and move some database archives to a backup server. After compressing several log files with gzip, the available space increases by only a few MB. You then delete some old database backups from /var/lib/mysql/backup, but the space usage shown by df remains unchanged. What is the most likely cause of this behavior?

Accepted Answer

Some processes have open file handles to the deleted files, preventing the space from being released.. When a file is deleted but still held open by a running process (e.g., the MySQL daemon or httpd), the filesystem does not release the disk space until all file handles are closed. In this scenario, the large log files in /var/log/httpd were compressed with gzip, but the original uncompressed files may still be open by the web server process, so deleting them (or the old database backups) does not free space until the process is restarted or the handles are released. This explains why df still shows 100% usage despite the deletions.

Answer

The disk quota for the mysql user is exceeded, so deletions do not reduce usage.

Answer

The SSD is not TRIM-enabled, so deleted blocks are not reclaimed.

Answer

The filesystem was remounted read-only due to errors, so deletions are not permanent.

Question 5

Which file is used by GRUB to load the kernel at boot time?

Accepted Answer

/boot/grub/grub.cfg. GRUB (GRand Unified Bootloader) reads its main configuration file, /boot/grub/grub.cfg, to determine which kernel to load and with what parameters. This file contains the menu entries, kernel paths, and initrd directives that GRUB uses at boot time. It is automatically generated by update-grub or grub-mkconfig based on scripts in /etc/grub.d/ and settings in /etc/default/grub.

Answer

/etc/grub.d/

Answer

/etc/default/grub

Answer

/boot/vmlinuz

Question 6

An administrator added a new APT repository to sources.list. Which command must be run to make the system aware of the packages from that repository?

Accepted Answer

apt update. After adding a new APT repository to sources.list, you must run 'apt update' (or 'apt-get update') to refresh the local package index from all configured repositories. This command downloads the latest package lists from the repository's Release and Packages files, making the system aware of available packages and their versions. Without this step, APT will not know about the new repository's packages, and subsequent install or upgrade commands will fail to find them.

Answer

apt-get upgrade

Answer

apt upgrade

Answer

apt-cache search

Question 7

Refer to the exhibit. Which file has a special permission that allows a user to execute the file with the privileges of the file owner?

Accepted Answer

/usr/bin/su. The /usr/bin/su command has the SUID (Set User ID) special permission set (typically mode 4755). This allows any user who executes the file to run it with the effective user ID of the file owner (root), enabling privilege escalation to perform administrative tasks. The SUID bit is represented by an 's' in the owner's execute position when viewed with ls -l.

Answer

/usr/bin/myapp

Answer

/tmp/shared

Answer

None of the above

Question 8

A system administrator is responsible for a production Debian 10 (buster) server that hosts a critical web application. The application requires the package 'libssl1.1' version 1.1.1 or higher, but the official Debian 10 repository only provides version 1.1.0. The administrator has already attempted to install the newer version from Debian 11 (bullseye) sources, but this caused dependency conflicts with the existing libc6 version. The server cannot be upgraded to Debian 11 due to application compatibility. The administrator needs to resolve this situation without breaking the existing system or introducing unofficial packages. Which of the following is the most appropriate course of action?

Accepted Answer

Add the Debian Backports repository for buster and install libssl1.1 from there.. Debian Backports provides newer versions of select packages (like libssl1.1) that are recompiled against the stable release's libraries (e.g., libc6 from buster), avoiding dependency conflicts. This allows the administrator to obtain libssl1.1 version 1.1.1 or higher without upgrading the entire system or introducing unofficial packages, maintaining system stability and security.

Answer

Upgrade the entire system to Debian 11 using a rolling upgrade.

Answer

Use dpkg --force-depends to force the installation of libssl1.1 from Debian 11.

Answer

Download the libssl1.1 source package from Debian 11 and compile it on the buster system with custom flags.

Question 9

A mail server using Postfix is rejecting emails from a partner domain. The administrator checks the maillog and sees 'relay access denied'. Which Postfix configuration parameter is most likely misconfigured?

Accepted Answer

mynetworks. (mynetworks) is correct because it defines which client IP addresses are allowed to relay mail through the server. The 'relay access denied' error indicates that the partner domain's mail server is not in the trusted network list. Option A (mydestination) specifies local destination domains, not relay permissions. Option B (inet_interfaces) controls listening interfaces. Option C (relayhost) sets the next-hop relay for outbound mail. Therefore, mynetworks is the likely misconfiguration.

Answer

mydestination

Answer

inet_interfaces

Answer

relayhost

Question 10

A system administrator needs to check if a filesystem has any errors without actually performing a repair. Which command should be used?

Accepted Answer

fsck -n /dev/sdb1. The `-n` option with `fsck` performs a read-only check, displaying any filesystem errors without making any modifications or repairs. This is the correct choice for a non-destructive check that only reports issues.

Answer

fsck -y /dev/sdb1

Answer

fsck -N /dev/sdb1

Answer

e2fsck -p /dev/sdb1

Question 11

A senior administrator runs a script that processes a CSV file. The script contains the following snippet: 'for field in $(cat data.csv); do ...'. The data.csv file contains lines like: 'John Doe, 123 Main St, Springfield'. The script fails to process correctly, splitting fields incorrectly and causing errors. Which of the following is the most appropriate fix?

Accepted Answer

Use a while loop with read: 'while IFS= read -r line; do ... done < data.csv'. The script fails due to word splitting and globbing when iterating over the output of `cat data.csv` with a `for` loop. Using `while IFS= read -r line` reads each line verbatim, preserving spaces and commas, and is the standard pattern for processing CSV or delimited files line by line in bash.

Answer

Use xargs to process each line

Answer

Use 'for field in $(<data.csv)' with proper quoting

Answer

Use 'for field in "$(cat data.csv)"' with double quotes around the substitution

Question 12

Refer to the exhibit. A user tries to execute a script on a mounted filesystem but gets a permission denied error. The script has execute permissions. What is the most likely cause?

Accepted Answer

The filesystem is mounted with the 'noexec' option.. The 'noexec' mount option prevents execution of any binary or script on the filesystem, regardless of file permissions. Even if the script has execute permissions set, the kernel will refuse to execute it when the filesystem is mounted with 'noexec'. This is a common security measure on filesystems like /tmp or /home to prevent unauthorized code execution.

Answer

The script is not executable for the user.

Answer

The user does not have read permission on the script.

Answer

The filesystem is full.

Question 13

Refer to the exhibit. Why does the cron job fail?

Accepted Answer

The script is not executable.. C is correct because cron jobs require the script to be executable (i.e., have the execute permission bit set). If the script is not executable, cron will fail to run it even if the shebang line and PATH are correct. The error typically appears in the cron log or as a silent failure.

Answer

The cron job lacks the PATH environment variable.

Answer

The script is owned by root, but the cron job runs as a different user.

Answer

The script lacks a shebang line.

Question 14

Refer to the exhibit. The system administrator notices the /var/log partition is nearly full. The syslog file is 2GB. Which command will safely reduce the size of this log file without stopping the logging daemon?

Accepted Answer

> /var/log/syslog. Using the shell redirection operator `> /var/log/syslog` truncates the file to zero length without deleting or closing its file descriptor. The syslog daemon (rsyslogd or syslogd) continues writing to the same inode, so no service interruption occurs. This is the safest method to free disk space while maintaining continuous logging.

Answer

cp /dev/null /var/log/syslog

Answer

rm /var/log/syslog && touch /var/log/syslog

Answer

mv /var/log/syslog /var/log/syslog.old

Question 15

Which THREE of the following are correct features of the 'grep' command? (Choose three.)

Accepted Answer

-i makes the search case-insensitive. The `-i` flag in `grep` performs case-insensitive matching, so patterns like 'error' will match 'Error', 'ERROR', etc. This is a common requirement when searching log files where case may vary.

Answer

-l prints line numbers of matches

Answer

-r enables regular expression matching

Question 16

Which command is used to compress a file with the highest compression ratio?

Accepted Answer

xz -9. `xz -9` uses the LZMA2 compression algorithm, which typically achieves a higher compression ratio than gzip (DEFLATE) or bzip2 (Burrows-Wheeler transform) at the cost of slower speed and higher memory usage. The `-9` flag sets the highest compression level, maximizing the ratio.

Answer

gzip -9

Answer

bzip2 -9

Answer

compress

Question 17

Which three options are valid ways to install a package 'curl' on a RHEL 8 system? (Choose three.)

Accepted Answer

`dnf install curl`. `dnf` is the default package manager on RHEL 8, replacing `yum` for handling RPM packages with automatic dependency resolution. It directly installs the `curl` package from configured repositories.

Answer

`apt-get install curl`

Answer

`zypper install curl`

Question 18

Which TWO commands are used to install packages on a Debian-based system? (Choose two.)

Accepted Answer

apt-get install. B is correct because `apt-get install` is the standard command-line tool for installing packages from Debian repositories, handling dependencies automatically. C is correct because `dpkg -i` installs a local `.deb` package file directly, though it does not resolve dependencies.

Answer

pacman -S

Answer

rpm -i

Answer

yum install

Question 19

A Linux administrator wants to update the local package index from all configured repositories on an Ubuntu system. Which command accomplishes this?

Accepted Answer

apt update. The `apt update` command (equivalent to `apt-get update`) refreshes the local package index by downloading the latest package lists from all repositories defined in `/etc/apt/sources.list` and `/etc/apt/sources.list.d/`. This is the prerequisite step before any installation or upgrade, ensuring the system knows about the newest available versions and dependencies.

Answer

dpkg --configure -a

Answer

apt upgrade

Answer

apt-get install

Question 20

An administrator needs to mount an ISO file located at /tmp/data.iso to /mnt/iso for read-only access. Which command should be used?

Accepted Answer

mount -o loop,ro /tmp/data.iso /mnt/iso. It uses the `-o loop,ro` options to mount the ISO file as a loop device with read-only access. The `loop` option is required to mount a file as a block device, and `ro` ensures the filesystem is mounted read-only, which is appropriate for an ISO image (typically an iso9660 filesystem).

Answer

mount /tmp/data.iso /mnt/iso

Answer

mount -t iso9660 -o loop /tmp/data.iso /mnt/iso

Answer

mount -o ro,loop /mnt/iso /tmp/data.iso