010-160 The Linux Operating System Practice Test 3 — 15 Questions

Question 1

Which TWO commands are commonly used to check network connectivity to a host?

Accepted Answer

ping. Option C, ping, is correct because it uses ICMP Echo Request and Echo Reply messages to verify basic IP-level reachability and round-trip time to a target host, making it the most common connectivity test. Option D, traceroute, is correct because it sends packets with incrementally increasing TTL values to map each router hop along the path to the destination, which helps diagnose where connectivity breaks down. Option A, arp, only resolves or displays IPv4-to-MAC address mappings in the local ARP cache and does not test end-to-end reachability. Option B, fdisk, is a disk partitioning utility unrelated to network diagnostics. Option E, ssh, establishes an encrypted remote login session over TCP port 22 but is not a general-purpose connectivity-checking command.

Answer

arp

Answer

fdisk

Answer

ssh

Question 2

Which THREE of the following items are typically found in the /etc directory?

Accepted Answer

/etc/fstab. /etc/fstab (B) is correct because it is the standard configuration file listing filesystems to be mounted at boot, including mount points, filesystem types, and mount options. /etc/passwd (C) is correct because it is the traditional system file storing user account information such as usernames, UIDs, GIDs, home directories, and login shells. /etc/hosts (D) is correct because it provides static hostname-to-IP-address mappings used by the system resolver before DNS. The other options do not belong: /etc/tmp (A) is not a standard file or directory in /etc, and /etc/bin (E) is not standard since executable binaries reside in /bin, /usr/bin, or /usr/local/bin, not under /etc.

Answer

/etc/tmp

Answer

/etc/bin

Question 3

Which TWO of the following are considered hardware components?

Accepted Answer

CPU. Option B (CPU) is correct because the Central Processing Unit is a physical integrated circuit that executes instructions, making it a core hardware component of any computer. Option C (RAM) is correct because Random Access Memory is a physical memory module (e.g., DIMM) that stores data and instructions for active processes, clearly a hardware device. In contrast, option A (Kernel) is the core software layer of an operating system that manages hardware resources, not hardware itself. Option D (Bash) is a software shell/command interpreter, and option E (systemd) is a software init and service manager; both are programs, not physical components.

Answer

Kernel

Answer

Bash

Answer

systemd

Question 4

An administrator needs to monitor network traffic in real-time on a specific interface. Which tool is commonly used to capture and display packets?

Accepted Answer

tcpdump. tcpdump is the classic command-line packet capture tool that reads frames from a network interface via libpcap and displays them in real time or writes them to a pcap file. It supports BPF filter expressions to narrow captured traffic, making it ideal for live monitoring on a specific interface (e.g., tcpdump -i eth0). This matches the requirement to capture and display packets.

Answer

netstat

Answer

iptables

Answer

nmap

Question 5

Which TWO of the following are valid ways to view system logs?

Accepted Answer

journalctl. Option D (journalctl) is correct because it is the systemd utility for querying the systemd journal, allowing you to view system and service logs (e.g., journalctl -u sshd, journalctl -b). Option E (dmesg) is correct because it prints the kernel ring buffer, showing kernel and hardware-related log messages such as boot and driver events. The unmarked options do not belong: lsmod lists loaded kernel modules, ifconfig configures/displays network interfaces, and top shows live process and resource usage — none of these display system logs.

Answer

lsmod

Answer

ifconfig

Answer

top

Question 6

Which THREE commands can be used to display information about system memory?

Accepted Answer

vmstat. Option B (vmstat) is correct because it reports virtual memory statistics, including swap usage, free and buffered memory, and paging activity. Option C (top) is correct because it displays a live, continuously updated view of memory usage (total, free, used, and buffers/cache) alongside process information. Option E (free) is correct because it directly shows total, used, free, shared, buffered/cached, and available physical and swap memory. Option A (ifconfig) is incorrect because it configures and displays network interface parameters, not memory. Option D (lsblk) is incorrect because it lists block devices and their mountpoints, which is storage rather than memory information.

Answer

ifconfig

Answer

lsblk

Question 7

Which TWO of the following are examples of Linux distributions?

Accepted Answer

Debian. Debian (C) is a Linux distribution: it packages the Linux kernel with GNU userland tools, the dpkg/APT package management system, and its own release repositories. Ubuntu (D) is also a Linux distribution, derived from Debian and maintained by Canonical, using the same .deb package format with its own release cycle and repositories. The remaining options are not Linux distributions: Chrome (A) is a proprietary web browser from Google, Windows (B) is a proprietary operating system family from Microsoft built on the NT kernel rather than the Linux kernel, and Office (E) is a productivity application suite, not an operating system distribution.

Answer

Chrome

Answer

Windows

Answer

Office

Question 8

Which THREE of the following are components of a standard network configuration?

Accepted Answer

Subnet mask. A standard network configuration on a host requires an IP address (B) to uniquely identify the interface on the network, a subnet mask (A) to define which portion of the address is the network prefix and which is the host portion (enabling local vs. remote delivery decisions), and a default gateway (E) so that traffic destined for networks outside the local subnet is forwarded to the next-hop router. These three values are the classic IPv4 host parameters (often delivered via DHCP or set statically with ip addr/ip route or ifconfig/route). By contrast, the shell prompt (C) is just the command-line interface indicator and has no bearing on network reachability, and the kernel version (D) describes the OS build rather than any addressing or routing parameter, so neither belongs in a network configuration.

Answer

Shell prompt

Answer

Kernel version

Question 9

Which TWO of the following directories are usually located at the root of a Linux filesystem?

Accepted Answer

/etc. Option A, /etc, is correct because it is a standard top-level directory directly under the root (/) in the Filesystem Hierarchy Standard, holding system-wide configuration files such as /etc/passwd and /etc/fstab. Option E, /bin, is also correct because it is a conventional root-level directory containing essential user command binaries like ls, cp, and bash (often symlinked to /usr/bin on modern distributions). The unmarked options do not belong: /users is not a standard FHS root directory (user home directories live under /home), while /windows and /programs are Windows-style paths with no place in a Linux filesystem hierarchy.

Answer

/users

Answer

/windows

Answer

/programs

Question 10

Which TWO of the following tools allow you to manage disk partitions?

Accepted Answer

fdisk. fdisk (A) is a classic Linux command-line utility used to create, delete, resize, and manage disk partitions on MBR and (in recent versions) GPT disks, so it directly satisfies the requirement. parted (B) is another partition-management tool that supports both MBR and GPT partitioning schemes and can create, resize, move, and delete partitions, making it equally valid for this task. The remaining options do not manage partitions: cat (C) concatenates and displays file contents, sed (D) is a stream editor for text transformation, and grep (E) searches text for pattern matches.

Answer

cat

Answer

sed

Answer

grep

Question 11

Which TWO of the following commands help in identifying hardware on a system?

Accepted Answer

lspci. lspci (option A) is correct because it enumerates the PCI bus and lists all PCI/PCIe devices such as GPUs, network adapters, and storage controllers, directly identifying hardware on the system. lsusb (option C) is correct because it queries the USB subsystem and lists connected USB devices (vendor and product IDs), which is another direct way to identify hardware. The remaining options do not identify hardware: pwd (B) prints the current working directory, whoami (D) prints the effective username, and date (E) displays the system date and time.

Answer

pwd

Answer

whoami

Answer

date

Question 12

Which THREE of the following files/commands are involved in system startup or services?

Accepted Answer

/etc/init.d. /etc/init.d is correct because it is the traditional SysV-style directory holding init scripts that start, stop, and restart system services, and it is directly involved in service management during startup. systemd is correct because it is the modern init system and service manager on most Linux distributions, responsible for booting the system and managing services via units. init is correct because it is the classic first process (PID 1) that initializes the system and launches services, and it remains the conceptual name for the startup process even under systemd. /etc/hosts is not correct because it is a static hostname-to-IP mapping file used for name resolution, not a startup or service component. /proc/cpuinfo is not correct because it is a virtual file exposing CPU information, unrelated to system startup or service management.

Answer

/etc/hosts

Answer

/proc/cpuinfo

Question 13

While exploring a Linux system, a new administrator runs `ls -l /etc/shadow` and sees that the file is owned by root and group shadow, with permissions `rw-r-----`. They want to understand which user accounts on the system are currently configured with a valid password hash versus those that are locked. Which command best lists only the accounts that have a real password hash set in `/etc/shadow`?

Accepted Answer

sudo awk -F: 'length($2) > 1 && $2 !~ /^[!*]/ {print $1}' /etc/shadow. The shadow file stores the password hash in the second colon-separated field. Accounts with a real hash have a string that is neither empty nor beginning with ! or *. The awk expression tests the length and the first character of that field, so it returns only usernames whose password hash is actually set. Reading /etc/shadow directly is also the authoritative method, since /etc/passwd no longer holds the hash on modern systems.

Answer

sudo cut -d: -f1,2 /etc/shadow | grep -v '^root'

Answer

sudo passwd -S -a | grep ' P '

Answer

sudo grep -v '^#' /etc/passwd | cut -d: -f1

Question 14

A Linux administrator needs to add a new user account named 'tester' with a home directory and a default shell of /bin/bash. Which command should be used?

Accepted Answer

useradd -m -s /bin/bash tester. The useradd command with -m and -s options creates a new user with a home directory and specified shell. This is the standard method for adding users in a non-interactive script or command line. Other commands like adduser may be distribution-specific or interactive, while usermod and passwd serve different purposes.

Answer

passwd -a tester -s /bin/bash -d /home/tester

Answer

adduser tester --shell /bin/bash --home /home/tester

Answer

usermod -m -s /bin/bash tester

Question 15

A user wants to check the amount of free disk space on all mounted filesystems in a human-readable format. Which command should they use?

Accepted Answer

df -h. df -h is the correct command to display free disk space on mounted filesystems in a human-readable format. It summarizes total, used, and available space per filesystem. Other commands like du, free, and lsblk serve different purposes, such as directory usage, memory usage, and block device listing, respectively.

Answer

du -h

Answer

free -h

Answer

lsblk -f