LPIC-1 Practice Test 5 — 25 Questions

Question 1

A system administrator suspects a failing power supply because the server randomly reboots. Which command can be used to check hardware health and event logs?

Accepted Answer

ipmitool sensor list. The `ipmitool sensor list` command queries the Baseboard Management Controller (BMC) via the IPMI protocol to retrieve real-time sensor readings (e.g., voltages, temperatures, fan speeds) and system event logs (SEL). This is the correct tool for diagnosing hardware-level issues like a failing power supply, as it provides direct access to the server's hardware health monitoring subsystem, independent of the operating system.

Answer

sensors -u

Answer

lspci -v

Answer

dmidecode -t baseboard

Question 2

A system takes a long time to boot due to a service that fails to start. Which systemd command can be used to identify the service causing the delay?

Accepted Answer

systemd-analyze blame. The `systemd-analyze blame` command prints a list of all running units, sorted by the time they took to initialize, making it the direct tool to identify which service is causing a boot delay. Unlike other options, it specifically measures and displays the initialization time of each unit, allowing you to pinpoint the slowest service.

Answer

journalctl -u service

Answer

systemctl status

Answer

systemd-analyze critical-chain

Question 3

Which TWO commands can be used to create an ext4 filesystem on a partition?

Accepted Answer

mkfs.ext4 /dev/sdb1. Option B, mkfs.ext4 /dev/sdb1, is correct because mkfs.ext4 is the dedicated front-end utility for creating an ext4 filesystem on the specified block device, invoking the ext4 filesystem code directly. Option C, mke2fs -t ext4 /dev/sdb1, is also correct because mke2fs is the underlying ext-family filesystem creation tool, and the -t ext4 flag explicitly selects the ext4 filesystem type, producing the same ext4 result. The unmarked options do not belong: mkfs.btrfs creates a Btrfs filesystem, mkfs.msdos creates a FAT filesystem, and mkfs.xfs creates an XFS filesystem, none of which are ext4.

Answer

mkfs.btrfs /dev/sdb1

Answer

mkfs.msdos /dev/sdb1

Answer

mkfs.xfs /dev/sdb1

Question 4

Refer to the exhibit. How much unpartitioned space is available on /dev/sda?

Accepted Answer

5.5G. The output of `fdisk -l /dev/sda` shows partitions sda1 (0.5G), sda2 (100G), and sda3 (150G), summing to 250.5G. The total disk size is 256G, so the unpartitioned space is 256G - 250.5G = 5.5G. Candidates often misread the partition sizes or add them incorrectly, leading to wrong answers.

Answer

256G

Answer

6G

Answer

150G

Question 5

A system administrator wants to ensure a service named 'app.service' starts automatically on boot in a systemd-based system. Which command should be used?

Accepted Answer

systemctl enable app.service. The correct command is 'systemctl enable app.service' because in systemd-based systems, 'enable' creates the necessary symlinks in the filesystem (typically under /etc/systemd/system/multi-user.target.wants/) to ensure the service starts automatically at boot. In contrast, 'systemctl start' only activates the service immediately without affecting its boot-time behavior.

Answer

systemctl start app.service

Answer

chkconfig app.service on

Answer

update-rc.d app.service enable

Question 6

A system administrator notices that the system boots to the graphical interface but wants to change it to boot to a non-graphical multi-user target. Which command will make this change persistent?

Accepted Answer

systemctl set-default multi-user.target. `systemctl set-default multi-user.target` changes the default systemd target to `multi-user.target`, which boots to a non-graphical multi-user environment. This change is persistent across reboots, as it updates the symlink `/etc/systemd/system/default.target` to point to `multi-user.target`.

Answer

systemctl isolate multi-user.target

Answer

systemctl enable multi-user.target

Answer

systemctl start multi-user.target

Question 7

A script reads a CSV file where fields may contain commas within quoted strings. Which approach correctly parses such fields?

Accepted Answer

Using awk or a dedicated tool like csvkit. CSV fields containing commas within quoted strings require a parser that understands CSV quoting rules. Awk can be scripted to handle quoted fields, and dedicated tools like csvkit (e.g., csvcut, csvformat) are designed specifically to parse CSV according to RFC 4180, correctly ignoring commas inside double-quoted strings.

Answer

Using 'cut -d',' -f1,2 file'

Answer

Using 'while IFS= read -r line; do ... done < file' and parsing manually

Answer

Using 'while IFS=',' read -r f1 f2; do ... done < file'

Question 8

A system administrator needs to locate the largest directories under /var to free up disk space. Which command is most appropriate?

Accepted Answer

du -sk /var/* | sort -rn. `du -sk /var/* | sort -rn` calculates the disk usage in kilobytes for each top-level item under /var, then sorts them numerically in reverse order, showing the largest directories first. This directly addresses the need to locate the largest directories to free up space, as `du` reports actual disk usage (including subdirectories) rather than file sizes.

Answer

df -h /var

Answer

find /var -size +100M

Answer

ls -lS /var

Question 9

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 10

A system administrator wants to display all lines in /var/log/syslog that do NOT contain the string 'error'. Which command accomplishes this?

Accepted Answer

grep -v 'error' /var/log/syslog. The `grep -v` option inverts the match, displaying only lines that do NOT contain the pattern. Therefore, `grep -v 'error' /var/log/syslog` outputs all lines from the file that lack the string 'error', which directly fulfills the requirement.

Answer

grep -r 'error' /var/log/syslog

Answer

grep -l 'error' /var/log/syslog

Answer

grep -i 'error' /var/log/syslog

Question 11

Which command adds a new group named 'developers' to the system?

Accepted Answer

groupadd developers. The correct command to add a new group on a Linux system is `groupadd developers`. This command creates a new group entry in the system's group database (typically /etc/group). The `groupadd` utility is the standard tool for this task in Linux, and it is part of the shadow-utils package.

Answer

addgroup developers

Answer

newgroup developers

Answer

groupadd -r developers

Question 12

You are a system administrator at a hosting company. A customer reports that their website hosted on a shared LAMP server is returning error 500. The server runs Ubuntu 22.04 with Apache, MySQL, and PHP. You log in and find that the /var partition (on /dev/sda3, ext4) is almost full. You identify that the MySQL database directory /var/lib/mysql contains several large binary logs that are no longer needed. You delete the binary logs using 'rm -f /var/lib/mysql/mysql-bin.*'. However, the available space does not increase. You also notice that an inode leak is suspected. You check inode usage with 'df -i' and see that the partition has plenty of free inodes. You then check with 'lsof | grep deleted' and see several entries for mysqld holding deleted files. What is the correct procedure to free the space?

Accepted Answer

Restart the MySQL service with 'systemctl restart mysql'.. When a file is deleted while a process (like mysqld) still holds an open file descriptor to it, the file's inode remains allocated and the disk space is not freed until the process releases the descriptor. Restarting the MySQL service (systemctl restart mysql) causes mysqld to close all open file descriptors, allowing the kernel to release the deleted binary logs' inodes and reclaim the disk space.

Answer

Use 'dpkg --purge mysql-server' to completely remove MySQL, then reinstall it.

Answer

Run 'e2fsck -f /dev/sda3' to reclaim inodes and fix filesystem inconsistencies.

Answer

Move the binary logs to a different partition using 'mv /var/lib/mysql/mysql-bin.* /tmp/' and then delete them.

Question 13

A system administrator is troubleshooting a server where the /var partition is full, causing services to fail. The administrator deletes old log files in /var/log, but the available space does not increase. Which step should be taken next?

Accepted Answer

Use 'lsof /var/log' to find processes holding deleted file handles, then restart those processes.. When a file is deleted while a process still holds an open file descriptor to it, the file's data blocks are not freed until that process releases the handle. The `lsof /var/log` command identifies such processes, and restarting them forces the kernel to release the deleted inodes, thereby reclaiming the disk space. This is why option C is the correct next step.

Answer

Run 'sync; echo 3 > /proc/sys/vm/drop_caches' to clear cache.

Answer

Remount the /var partition with the 'noatime' option.

Answer

Run 'df -i' to check inode usage.

Question 14

An administrator needs to extend a logical volume by 10GB. The volume group has available physical extents. Which command should be used?

Accepted Answer

lvextend -L +10G /dev/vg/lv. The `lvextend` command with the `-L +10G` flag increases the size of the existing logical volume `/dev/vg/lv` by exactly 10 GB, using available physical extents from the volume group. This is the standard LVM command for extending a logical volume without recreating it.

Answer

lvcreate -L 10G /dev/vg/lv

Answer

vgextend /dev/vg/lv -L +10G

Answer

lvresize -L 10G /dev/vg/lv

Question 15

An administrator needs to extract only the fifth field from a colon-delimited file, but some lines contain fewer than five fields and must be skipped rather than printed as empty. Which awk program accomplishes this?

Accepted Answer

awk -F: 'NF >= 5 {print $5}' file. The requirement is to skip records that lack a fifth field, which is exactly what the NF field-count variable expresses. Testing NF >= 5 before printing $5 rejects short lines at the source, whereas tests on the value or length of $5 conflate an absent field with a present-but-empty one and can silently drop legitimate empty fields. Using NF keeps the decision tied to the record's structure.

Answer

awk -F: '$5 != "" {print $5}' file

Answer

awk -F: '{print $5}' file | grep -v '^$'

Answer

awk -F: 'length($5) > 0 {print $5}' file

Question 16

Refer to the exhibit. An administrator attempts to remount /mnt as read-only but receives the error shown. What is the most likely cause?

Accepted Answer

The /mnt directory is not a mount point. The error 'mount: /mnt is not a mount point' indicates that the administrator attempted to use the `remount` option on a directory that is not currently a mount point. The `mount -o remount` command only works on directories where a filesystem is already mounted; it modifies the mount options of an existing mount, not a regular directory. Since /mnt is not a mount point, the kernel rejects the operation with this specific error.

Answer

The /mnt directory is not empty

Answer

The /mnt directory does not exist

Answer

The filesystem is already mounted read-only

Question 17

After connecting a USB device, the system does not create a device node in /dev. Which command can be used to trigger udev to re-evaluate the device?

Accepted Answer

udevadm trigger. The correct command is `udevadm trigger`. This command causes udev to re-evaluate all devices by simulating kernel uevents, which forces udev to process rules and create device nodes in /dev for devices that were missed or not properly initialized.

Answer

modprobe

Answer

udevadm control --reload

Answer

udevadm settle

Question 18

A user needs to schedule a backup script to run every weekday at 2:00 AM. Which command should they use to set up this recurring job?

Accepted Answer

crontab -e and add a line. The cron daemon is the standard Linux tool for scheduling recurring jobs at specific times. Using `crontab -e` allows the user to edit their personal crontab file and add a line like `0 2 * * 1-5 /path/to/backup.sh` to run the script every weekday (Monday through Friday) at 2:00 AM.

Answer

sleep 3600 && ./backup.sh

Answer

at -f backup.sh 2:00

Answer

batch

Question 19

Refer to the exhibit. The remount command fails. What is the most likely cause?

Accepted Answer

The filesystem is not mounted.. The remount command fails because the filesystem is not mounted. 'mount -o remount' only works on filesystems that are already mounted. The lack of the 'noauto' option in the fstab entry is irrelevant; it only affects automatic mounting at boot and does not influence whether a remount can be performed on an unmounted filesystem. Candidates may incorrectly believe that the missing 'noauto' is the cause, but the real issue is that the filesystem needs to be mounted first.

Answer

The filesystem type is wrong.

Answer

The fstab entry lacks the 'noauto' option but the device is not currently mounted.

Answer

The mount point /data does not exist.

Question 20

Based on the exhibit, which of the following is true about the cleanup.sh job?

Accepted Answer

It runs at 4:30 AM on Monday through Friday. The cron expression `30 4 * * 1-5` specifies that the job runs at minute 30, hour 4 (4:30 AM), every day of month (*), every month (*), but only on days of the week 1 through 5 (Monday=1, Tuesday=2, Wednesday=3, Thursday=4, Friday=5). Therefore, the job runs at 4:30 AM on Monday through Friday.

Answer

It runs at 4:30 AM every day

Answer

It runs at 4:00 AM on weekdays

Answer

It runs at 4:30 AM on weekends