LPIC-1 Practice Test 17 — 15 Questions

Question 1

An administrator adds the line 'DenyUsers john' to /etc/ssh/sshd_config and restarts the SSH service. What is the effect?

Accepted Answer

User john cannot log in via SSH.. The 'DenyUsers' directive in /etc/ssh/sshd_config explicitly blocks the specified user(s) from authenticating via SSH. When the SSH service is restarted, the configuration is reloaded, and user 'john' will be denied SSH login attempts at the authentication layer, before any shell or command execution occurs.

Answer

User john can still log in but his commands are logged.

Answer

User john is denied all shell access, including local and console logins.

Answer

All users except john cannot log in via SSH.

Question 2

Refer to the exhibit. An admin attempts to execute a shell script located in /tmp but gets 'Permission denied'. Which mount option is most likely causing this?

Accepted Answer

noexec. The 'noexec' mount option prevents execution of any binary or script directly from the filesystem, regardless of file permissions. Since the script is in /tmp and the admin gets 'Permission denied' despite correct execute bits, the /tmp partition is likely mounted with noexec, which is a common security hardening practice.

Answer

relatime

Answer

nodev

Answer

nosuid

Question 3

An ext4 filesystem is experiencing performance degradation due to very frequent small writes. Which tune2fs option can help by reserving a percentage of blocks for the root user to prevent fragmentation?

Accepted Answer

-g root. The -g option in tune2fs sets the group that can use the reserved blocks. By specifying 'root', it assigns the reserved blocks to the root group, ensuring that the root user can access this reserved space. This helps prevent fragmentation by keeping free blocks available for root's small writes, rather than allowing the filesystem to become completely full. Options A and C are unrelated to block reservation. Option D sets the reserved block percentage to 0, which does not reserve any blocks and can actually increase fragmentation.

Answer

-i 0

Answer

-c 0

Answer

-m 0

Question 4

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 5

A system administrator wants to monitor a log file in real-time for lines containing 'ERROR' and write them to a separate file. Which command combination is most appropriate?

Accepted Answer

tail -f logfile | grep 'ERROR' > error.log. `tail -f logfile` continuously outputs new lines appended to the file, and piping that output into `grep 'ERROR'` filters only lines containing 'ERROR', which are then redirected to `error.log`. This combination achieves real-time monitoring and selective logging without blocking the terminal or requiring manual intervention.

Answer

less logfile

Answer

vi logfile

Answer

cat logfile | grep 'ERROR' > error.log

Question 6

Which three commands are commonly used to display information about running processes?

Accepted Answer

top. top (A) is correct because it launches an interactive, real-time view of running processes, showing CPU, memory, and load statistics refreshed continuously. htop (D) is correct because it is an enhanced interactive process viewer that displays running processes with colorized, scrollable output and additional metrics like per-core CPU usage. ps (E) is correct because it snapshots the current processes and their details (PID, TTY, time, command), commonly used with options such as aux or -ef. pkill (B) is not a display tool but sends signals to processes by name to terminate them, and kill (C) likewise sends signals to specific PIDs rather than showing process information.

Answer

pkill

Answer

kill

Question 7

A Linux system administrator is tasked with setting up a new server that will host multiple virtual machines using KVM. The server has 64 GB of RAM and two physical CPUs, each with 8 cores (16 threads). The administrator needs to allocate resources efficiently. The VMs will have varying workloads. The administrator wants to ensure that the host system has enough resources for itself and that VMs can use all available CPU cores. Which approach should the administrator take to configure CPU allocation for the host and VMs?

Accepted Answer

Use CPU pinning to reserve two physical cores for the host and distribute the remaining cores among VMs using host-passthrough mode.. It reserves two physical cores for the host system to ensure its stability and performance, while distributing the remaining cores among VMs using CPU pinning and host-passthrough mode. This approach allows VMs to access the full CPU feature set and all available cores efficiently, balancing host overhead with VM resource needs in a KVM environment.

Answer

Use QEMU emulation instead of KVM to reduce CPU overhead.

Answer

Pin all physical CPU cores to the VMs using virsh vcpupin, and leave no cores for the host.

Answer

Overcommit CPU resources by assigning 32 vCPUs to each VM, relying on the hypervisor to schedule.

Question 8

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 9

A Linux administrator is managing a server that uses RPM-based package management. They need to find which installed package provides the '/etc/ssh/sshd_config' file. Which command should they use?

Accepted Answer

rpm -qf /etc/ssh/sshd_config. The correct command is `rpm -qf /etc/ssh/sshd_config`. The `-q` flag queries the RPM database, and `-f` (or `--file`) tells RPM to find which installed package owns the specified file. This is the standard way to map a file back to its originating package in RPM-based systems.

Answer

rpm -qi /etc/ssh/sshd_config

Answer

rpm -ql /etc/ssh/sshd_config

Answer

rpm -qa | grep sshd_config

Question 10

A user reports that they cannot access the company's web server. The administrator confirms the server is running and network connectivity is fine. Which command should be used to verify that the HTTP service is listening on the correct port?

Accepted Answer

ss -tlnp. `ss -tlnp`, is correct because it lists TCP listening sockets with their port numbers and associated processes. The `-t` flag filters for TCP, `-l` shows only listening sockets, `-n` displays numeric addresses and ports (avoiding DNS lookups), and `-p` reveals the process ID/name. This directly verifies whether the HTTP service (typically port 80 or 443) is actively listening on the expected interface.

Answer

ping 127.0.0.1

Answer

netstat -rn

Answer

iperf3 -c localhost

Question 11

An administrator needs to determine which package owns the file /usr/bin/htop on a Debian-based system so that the package can be reinstalled after corruption. Which command provides this information?

Accepted Answer

dpkg -S /usr/bin/htop. On Debian-based systems, the local package database tracks which package installed each file. The dpkg search option queries that database by file path, returning the owning package, which is precisely the reverse lookup needed before reinstallation.

Answer

dpkg -L htop

Answer

apt-file search /usr/bin/htop

Answer

apt-cache show htop

Question 12

A Linux administrator needs to extract all lines from `/var/log/syslog` that contain the word `error` (case-insensitive) and save them to `errors.txt`. Which command accomplishes this?

Accepted Answer

grep -i error /var/log/syslog > errors.txt. The grep command with -i performs a case-insensitive search, and the > redirection writes the matching lines to a file. The other options either invert the match, count matches, or list filenames, none of which produce the desired output of the matching lines themselves.

Answer

grep -c error /var/log/syslog > errors.txt

Answer

grep -v error /var/log/syslog > errors.txt

Answer

grep -l error /var/log/syslog > errors.txt

Question 13

Which TWO of the following are valid methods to specify a partition in /etc/fstab?

Accepted Answer

PARTUUID. Options A (PARTUUID), B (UUID), and C (LABEL) are all valid device specifiers in the first field of /etc/fstab. UUID= and LABEL= reference the filesystem UUID and filesystem label, while PARTUUID= references the partition-table UUID (GUID) of the partition. For example, 'UUID=1234-ABCD / ext4 defaults 0 1', 'LABEL=root / ext4 defaults 0 1', and 'PARTUUID=12345678-01 / ext4 defaults 0 1' are all valid and resolved at mount time. Options D (DEVPATH) and E (ID) are not valid fstab device specifiers; they are udev properties and are not recognized fstab tags.

Answer

DEVPATH

Answer

ID

Question 14

Which THREE package management tools are native to Debian-based Linux distributions? (Choose exactly three.)

Accepted Answer

dpkg. dpkg is the core low-level package manager for Debian-based distributions, handling the installation, removal, and querying of .deb packages directly. It does not resolve dependencies automatically, making it the foundational tool upon which higher-level tools like APT are built.

Answer

rpm

Answer

yum

Question 15

A Linux system has a software RAID1 array /dev/md0 consisting of /dev/sda1 and /dev/sdb1. After replacing a failed disk, the administrator runs 'mdadm --manage /dev/md0 --add /dev/sdc1', but the array remains degraded. Which command should be used to check the status of the array?

Accepted Answer

mdadm --detail /dev/md0. The `mdadm --detail /dev/md0` command displays the current state of the RAID array, including its status (e.g., degraded, active), the number of active and failed devices, and the sync/resync progress. Since the array remains degraded after adding a new disk, this command will show whether the new disk has been properly integrated or if there is an underlying issue, such as a missing or failed component.

Answer

mdadm --examine /dev/sdc1

Answer

mdadm --version

Answer

mdadm --query /dev/md0