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CCNA It Infrastructure Questions

44 of 119 questions · Page 2/2 · It Infrastructure topic · Answers revealed

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76

MCQeasy

A network printer should always receive the same IP address to ensure reliable access. Which configuration method guarantees this?

A.Static IP address

B.DHCP reservation

C.Dynamic IP address

D.APIPA

AnswerA

A static IP address remains constant, ensuring the printer is always reachable.

Why this answer

A static IP address is manually configured on the printer itself, ensuring it never changes regardless of network conditions or DHCP server availability. This guarantees the printer always receives the same IP address because the assignment is hard-coded and not subject to lease expiration or server failures.

Exam trap

The trap here is that candidates often confuse DHCP reservation with static IP, thinking both guarantee the same address, but the exam tests the understanding that a static IP is configured on the device itself and does not depend on any server, whereas a reservation still relies on DHCP server availability and proper lease renewal.

How to eliminate wrong answers

Option B is wrong because a DHCP reservation assigns a fixed IP address from the DHCP server, but if the server is down or the printer is moved to a different subnet, it may not receive that address. Option C is wrong because a dynamic IP address is leased from a DHCP server and can change when the lease expires or the device reconnects. Option D is wrong because APIPA (Automatic Private IP Addressing) assigns a random link-local address in the 169.254.0.0/16 range when no DHCP server is available, which is not guaranteed to be consistent and cannot be relied upon for network printing.

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77

MCQmedium

A company has two departments on separate floors and wants to connect them into a single local area network (LAN). Which device should be used to interconnect the switches on each floor?

A.Router

B.Modem

C.Switch

D.Hub

AnswerC

Switches connect devices within the same network, allowing multiple switches to extend a LAN.

Why this answer

A switch is the correct device because it operates at Layer 2 (Data Link layer) and can forward frames based on MAC addresses, allowing multiple switches to be interconnected to extend a single broadcast domain and form a larger LAN. Connecting switches on different floors via Ethernet cables or fiber uplinks creates a unified local area network without requiring routing or network-layer addressing.

Exam trap

The trap here is that candidates often confuse a router as necessary for connecting any two network segments, but when the goal is to extend the same LAN (same subnet and broadcast domain), a Layer 2 switch is the appropriate device, not a router.

How to eliminate wrong answers

Option A is wrong because a router operates at Layer 3 (Network layer) and is used to connect different networks or subnets, not to extend a single LAN; using a router would segment the network and require IP routing. Option B is wrong because a modem modulates/demodulates signals for WAN connections (e.g., DSL, cable) and is not designed to interconnect local switches within a building. Option D is wrong because a hub is a Layer 1 device that simply repeats electrical signals, lacks MAC address learning, and would create a single collision domain, leading to inefficiency and increased collisions when interconnecting switches.

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78

MCQeasy

A user's laptop battery no longer holds a charge and the laptop only works when plugged in. Which component should be replaced?

A.Battery

B.RAM

C.Hard drive

D.Power adapter

AnswerA

The battery is the component that holds charge and needs replacement when it fails.

Why this answer

Option D is correct because the battery is the component that stores charge. The hard drive (A), RAM (B), and power adapter (C) do not affect battery charging.

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79

MCQhard

A network administrator wants to restrict access to the wireless network to only approved devices. Which security feature should be enabled on the access point?

A.Firewall rules

B.Disable SSID broadcast

C.WPA2 encryption

D.MAC filtering

AnswerD

MAC filtering allows only whitelisted MAC addresses to connect.

Why this answer

MAC filtering allows the access point to permit or deny network access based on the device's MAC address, which is a unique hardware identifier. By creating an allowlist of approved MAC addresses, the administrator can restrict the wireless network to only those devices. This directly addresses the requirement to limit access to approved devices.

Exam trap

The trap here is that candidates often confuse MAC filtering with encryption or SSID hiding, thinking that hiding the network or using strong encryption alone can restrict device access, but neither prevents an unauthorized device from connecting if it has the SSID or password.

How to eliminate wrong answers

Option A is wrong because firewall rules control traffic flow based on IP addresses, ports, or protocols, not device identity, and they do not restrict which devices can associate with the wireless network. Option B is wrong because disabling SSID broadcast only hides the network name from beacon frames; it does not prevent unauthorized devices from connecting if they know the SSID. Option C is wrong because WPA2 encryption secures data in transit and requires a pre-shared key or authentication server, but it does not restrict access to specific approved devices—any device with the correct credentials can connect.

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80

Multi-Selectmedium

Which THREE of the following are types of network topologies?

Select 3 answers

A.Mesh

B.Star

C.Bus

D.Triangle

E.Circle

AnswersA, B, C

Each device connects to many others.

Why this answer

A mesh topology connects each device to every other device, providing high redundancy and fault tolerance. It is a valid network topology type commonly used in WANs and wireless networks.

Exam trap

CompTIA often tests that only the three standard topologies (mesh, star, bus) are correct, and traps candidates into selecting 'circle' or 'triangle' because they sound like plausible geometric network shapes.

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81

Multi-Selecthard

A network technician is troubleshooting a server that is not reachable from the LAN. The server has a static IP address of 192.168.1.100/24 and a default gateway of 192.168.1.1. The technician pings the gateway successfully but cannot ping the server from another workstation on the same subnet. Which TWO steps should the technician take to resolve the issue?

Select 2 answers

A.Clear the ARP cache on the server

B.Replace the network cable

C.Verify the network adapter settings on the server

D.Check DNS resolution for the server

E.Check the server's firewall settings

AnswersC, E

Misconfigured adapter could cause subnet mismatch.

Why this answer

Option C is correct because the technician can ping the gateway from the server, confirming Layer 3 connectivity to the router, but cannot ping the server from another workstation on the same subnet. This points to a local configuration issue on the server itself, such as a misconfigured subnet mask, a disabled network adapter, or incorrect IP settings. Verifying the network adapter settings ensures the server's IP address, subnet mask, and default gateway are correctly applied and the adapter is enabled.

Exam trap

The trap here is that candidates assume a successful ping to the gateway means the server is fully reachable, overlooking that local subnet communication requires correct subnet mask and adapter settings, not just gateway connectivity.

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82

MCQeasy

A user cannot connect to the internet. Which step is most appropriate to start troubleshooting?

A.Update the graphics driver

B.Replace the router

C.Reinstall the operating system

D.Check the network cable connection

AnswerD

Checking the physical cable is a fundamental step to ensure the link is active.

Why this answer

The most appropriate first step in troubleshooting a network connectivity issue is to check the physical layer (Layer 1 of the OSI model). A loose or unplugged network cable is a common cause of connectivity loss, and verifying the cable connection is quick, non-invasive, and follows the principle of starting with the simplest possible cause before escalating to more complex solutions.

Exam trap

CompTIA often tests the troubleshooting methodology by presenting a flashy, high-level solution (like reinstalling the OS) to distract from the fundamental step of verifying the physical connection, which candidates may overlook due to overthinking the problem.

How to eliminate wrong answers

Option A is wrong because updating the graphics driver addresses display or rendering issues, not network connectivity; graphics drivers have no role in TCP/IP or Ethernet communication. Option B is wrong because replacing the router is a drastic, costly step that should only be considered after verifying all simpler components (cables, device settings, ISP status) and is not a starting point. Option C is wrong because reinstalling the operating system is an extreme measure that wipes user data and applications; it is reserved for software corruption or malware, not for a basic connectivity problem that could be caused by a disconnected cable.

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83

Multi-Selecteasy

A user reports that their computer is not turning on. Which TWO hardware components should be checked first?

Select 2 answers

A.CPU

B.Power outlet

C.RAM

D.Power supply

E.Hard drive

AnswersB, D

A dead power outlet is a simple cause that should be verified first.

Why this answer

The power outlet is the first component to check because it is the most basic point of failure in the power delivery chain. If the outlet is dead or switched off, no power reaches the system, making it impossible for the computer to turn on. Verifying the outlet with a known working device (e.g., a lamp) quickly isolates this common issue before inspecting internal hardware.

Exam trap

The trap here is that candidates often jump to internal components like the power supply or CPU first, forgetting the simplest external cause—a dead or switched-off power outlet—which is the most logical and quickest check in the troubleshooting process.

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84

Multi-Selectmedium

A user reports that their laptop cannot connect to the corporate Wi-Fi. Other devices are working fine. Which TWO troubleshooting steps should the technician take first? (Choose TWO.)

Select 2 answers

A.Verify the SSID and password on the laptop.

B.Check the DHCP server for available IP addresses.

C.Update the network adapter driver.

D.Check if the laptop's wireless switch is turned on.

E.Restart the wireless router.

AnswersA, D

Incorrect credentials are a common cause.

Why this answer

Option A is correct because verifying the SSID and password is the most basic and common cause of a single device failing to connect to Wi-Fi. If other devices are working, the issue is isolated to the laptop, so checking its wireless configuration is a logical first step. This aligns with the 'isolate the problem' troubleshooting methodology.

Exam trap

The trap here is that candidates may jump to network-wide solutions (like restarting the router or checking DHCP) instead of focusing on the single affected device, ignoring the principle of 'start with the simplest and most likely cause first.'

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85

MCQmedium

Refer to the exhibit. A user can successfully ping the local default gateway but cannot ping an external IP address. What is the most likely cause?

A.The internet connection is down

B.The network interface card is faulty

C.The DNS server is not responding

D.The subnet mask is misconfigured

AnswerA

The gateway works but external IP fails, indicating an issue beyond the gateway.

Why this answer

Since the user can successfully ping the local default gateway, the Layer 2 and Layer 3 connectivity within the local subnet is intact, ruling out issues with the NIC, subnet mask, or local routing. The failure to ping an external IP address indicates that traffic is not being forwarded beyond the local network, which most commonly occurs when the internet connection (WAN link) is down or the ISP's upstream router is unreachable.

Exam trap

CompTIA often tests the distinction between local connectivity (Layer 2/3 within subnet) and external connectivity (Layer 3 routing beyond the gateway), leading candidates to incorrectly blame DNS or subnet mask when the real issue is the upstream connection.

How to eliminate wrong answers

Option B is wrong because a faulty network interface card would prevent all network communication, including the successful ping to the local default gateway. Option C is wrong because DNS resolution is not required to ping an external IP address; the ping command uses the IP address directly, so a non-responsive DNS server would not affect this test. Option D is wrong because a misconfigured subnet mask would cause the user to be unable to reach the default gateway itself, as the system would not correctly determine that the gateway is on the same subnet.

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86

Multi-Selecthard

Which THREE of the following are examples of Infrastructure as a Service (IaaS) offerings? (Select THREE.)

Select 3 answers

A.Object storage service

B.Virtual machine instances in the cloud

C.Managed database service

D.Web-based email application

E.Cloud load balancer

AnswersA, B, E

Storage is a fundamental IaaS component.

Why this answer

Object storage service is an IaaS offering because it provides raw storage resources over the internet, allowing users to store and retrieve data without managing the underlying hardware. In IaaS, the cloud provider handles the physical infrastructure, while the customer controls the storage configuration and access. This aligns with the IaaS model of offering fundamental computing resources like storage, compute, and networking.

Exam trap

The trap here is that candidates confuse managed services (like databases) with IaaS, not realizing that PaaS abstracts more of the management layer, while IaaS provides raw compute, storage, and networking resources.

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87

MCQmedium

A small business wants to connect its computers to share files and printers. Which of the following network devices would BEST facilitate this?

A.Switch

B.Router

C.Hub

D.Modem

AnswerA

A switch creates a local network and allows file/printer sharing.

Why this answer

A switch operates at Layer 2 of the OSI model and uses MAC addresses to forward frames only to the specific port where the destination device is connected. This creates a dedicated, collision-free path between the computers, making it the ideal device for connecting multiple computers within a local area network (LAN) to share files and printers efficiently.

Exam trap

The trap here is that candidates often confuse a switch with a hub, assuming both simply 'connect' devices, but the exam tests the understanding that a switch provides intelligent, collision-free forwarding at Layer 2, while a hub is a dumb repeater that degrades performance in a LAN.

How to eliminate wrong answers

Option B (Router) is wrong because a router operates at Layer 3 and is designed to connect different networks (e.g., a LAN to the internet), not to directly interconnect computers within the same LAN for file and printer sharing. Option C (Hub) is wrong because a hub is a Layer 1 device that blindly repeats all incoming signals to every port, causing collisions and inefficient bandwidth usage, which is unsuitable for reliable file and printer sharing. Option D (Modem) is wrong because a modem modulates and demodulates signals to connect a LAN to an internet service provider (ISP), not to interconnect local computers.

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88

MCQmedium

A network technician is setting up a wireless network. To minimize interference from neighboring networks, which wireless frequency band is typically less congested?

A.900 MHz

B.5 GHz

C.2.4 GHz

D.60 GHz

AnswerB

5 GHz provides more channels and less interference.

Why this answer

The 5 GHz band is typically less congested than the 2.4 GHz band because it has more non-overlapping channels (23 vs. 3) and is used by fewer devices, including legacy Wi-Fi clients. This reduces co-channel interference from neighboring networks, making 5 GHz the preferred choice for minimizing interference in dense wireless environments.

Exam trap

The trap here is that candidates assume 2.4 GHz is less congested because it has longer range, but they overlook that its limited non-overlapping channels and ubiquitous use by non-Wi-Fi devices (microwaves, Bluetooth) make it far more congested than 5 GHz.

How to eliminate wrong answers

Option A is wrong because 900 MHz is an ISM band used primarily for IoT, RFID, and legacy cordless phones, not for standard Wi-Fi (802.11), and it offers very low data rates, making it unsuitable for typical wireless networking. Option C is wrong because 2.4 GHz is the most congested band due to its widespread use by Wi-Fi (802.11b/g/n), Bluetooth, microwaves, and cordless phones, with only three non-overlapping channels (1, 6, 11) in the 2.4 GHz spectrum, leading to high interference. Option D is wrong because 60 GHz (802.11ad/ay) is a millimeter-wave band used for short-range, high-speed links (e.g., WiGig) but is not typically less congested for general Wi-Fi; it has very limited range and is blocked by walls, making it irrelevant for minimizing interference from neighboring networks in typical deployments.

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89

MCQeasy

Which of the following cable types is MOST commonly used for Ethernet networks in an office?

A.Coaxial

B.Fiber optic

C.USB

D.Cat5e

AnswerD

Cat5e supports Gigabit Ethernet and is widely used.

Why this answer

Cat5e (Category 5 enhanced) is the most common twisted-pair copper cable used in office Ethernet networks because it supports speeds up to 1 Gbps (1000BASE-T) over distances up to 100 meters, and it is backward-compatible with older 10/100 Mbps standards. Its widespread adoption, low cost, and ease of termination make it the default choice for structured cabling in modern office environments.

Exam trap

The trap here is that candidates often confuse 'most common for office Ethernet' with 'highest performance,' leading them to choose fiber optic (B) instead of recognizing that Cat5e is the practical, cost-effective standard for everyday office desktop connections.

How to eliminate wrong answers

Option A is wrong because coaxial cable (e.g., RG-6 or RG-59) is primarily used for cable television, broadband internet (DOCSIS), or legacy 10BASE2/10BASE5 Ethernet, not for modern office Ethernet networks. Option B is wrong because fiber optic cable, while capable of much higher speeds and longer distances, is more expensive and fragile to terminate, making it less common for general office desktop connections; it is typically reserved for backbone or data center links. Option C is wrong because USB (Universal Serial Bus) is a peripheral interface for connecting devices like keyboards, mice, and external storage, not a standard for Ethernet networking; while USB-to-Ethernet adapters exist, the cable itself is not used for Ethernet networks.

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90

MCQhard

A technician is troubleshooting a workstation that cannot connect to a server at 192.168.1.100. The workstation's IP configuration shows: IP: 192.168.2.50, Subnet: 255.255.255.0, Gateway: 192.168.2.1. Which of the following is the MOST likely cause of the connectivity issue?

A.Incorrect default gateway

B.Incorrect subnet mask

C.Duplicate IP address on the network

D.Workstation and server are on different subnets with no routing

AnswerD

Without a router, devices on different subnets cannot communicate.

Why this answer

The workstation's IP address (192.168.2.50) and the server's IP address (192.168.1.100) belong to different subnets (192.168.2.0/24 and 192.168.1.0/24, respectively). Without a router configured to forward traffic between these subnets, the workstation cannot reach the server, even though the default gateway (192.168.2.1) is correct for its own subnet.

Exam trap

The trap here is that candidates often assume any connectivity failure is due to an incorrect default gateway, but the gateway is actually correct for the workstation's subnet; the real issue is that the two devices are on different subnets with no router to bridge them.

How to eliminate wrong answers

Option A is wrong because the default gateway (192.168.2.1) is on the same subnet as the workstation (192.168.2.0/24), so it is correctly configured for local subnet traffic. Option B is wrong because the subnet mask (255.255.255.0) is standard and correctly defines the workstation's local network as 192.168.2.0/24. Option C is wrong because there is no evidence of a duplicate IP address; the issue is purely about subnet mismatch and lack of routing, not an address conflict.

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91

MCQeasy

A user reports that their computer is slow when running multiple applications simultaneously. Which component upgrade would best improve performance?

A.RAM

B.Video card

C.CPU

D.Hard drive

AnswerA

Adding RAM increases the amount of memory available to run multiple applications simultaneously.

Why this answer

When multiple applications run simultaneously, the operating system uses RAM to store active data for quick access. Insufficient RAM forces the system to rely on the hard drive as virtual memory (paging), which is dramatically slower. Upgrading RAM reduces this paging activity, improving multitasking performance.

Exam trap

The trap here is that candidates often confuse a slow system with a CPU bottleneck, but the question specifically describes running multiple applications simultaneously, which points to RAM as the limiting factor, not processor speed.

How to eliminate wrong answers

Option B (Video card) is wrong because a video card accelerates graphics rendering, not general multitasking or application responsiveness. Option C (CPU) is wrong because while a faster CPU improves single-threaded processing, the bottleneck in multitasking with many open applications is typically memory capacity, not processing speed. Option D (Hard drive) is wrong because upgrading to an SSD improves boot and load times, but does not directly address the RAM shortage that causes slowdowns when running multiple applications simultaneously.

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92

MCQeasy

A company wants to use a cloud service where they provide their own operating system and applications, but the provider manages the physical hardware and virtualization layer. Which cloud service model does this describe?

A.Platform as a Service (PaaS)

B.Infrastructure as a Service (IaaS)

C.Desktop as a Service (DaaS)

D.Software as a Service (SaaS)

AnswerB

IaaS gives virtual machines where customers manage OS and applications.

Why this answer

Infrastructure as a Service (IaaS) provides virtualized computing resources over the internet, where the customer manages the operating system, applications, and middleware, while the cloud provider handles the physical hardware, storage, and network infrastructure. In this model, the provider manages the virtualization layer (hypervisor) and underlying physical servers, but the customer retains full control over the OS and applications, matching the scenario exactly.

Exam trap

The trap here is that candidates often confuse PaaS with IaaS because both involve cloud infrastructure, but PaaS abstracts away the OS management, whereas IaaS gives the customer full OS control, which is the key differentiator in this scenario.

How to eliminate wrong answers

Option A (PaaS) is wrong because Platform as a Service provides a managed runtime environment where the provider manages the OS and middleware, and the customer only deploys their own applications, not the operating system. Option C (DaaS) is wrong because Desktop as a Service delivers virtual desktops managed by the provider, including the OS, and the customer does not provide their own OS. Option D (SaaS) is wrong because Software as a Service delivers fully managed applications accessed via a web browser, with no customer control over the OS or underlying infrastructure.

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93

MCQmedium

A technician is troubleshooting a network slowdown. The technician suspects a loop in the network. Which of the following protocols would prevent such a loop?

AnswerA

STP prevents loops by disabling redundant paths.

Why this answer

STP (Spanning Tree Protocol) is the correct answer because it is specifically designed to prevent network loops in Ethernet networks by dynamically blocking redundant paths. When a loop occurs, broadcast frames can circulate endlessly, causing a broadcast storm that degrades network performance. STP ensures a loop-free topology by placing some switch ports into a blocking state while maintaining redundant links for failover.

Exam trap

CompTIA often tests the misconception that protocols like DNS or DHCP can solve layer 2 issues, but the trap here is that candidates confuse network services (DNS, DHCP) with layer 2 loop-prevention mechanisms, forgetting that STP is the only protocol among the options that operates at the data link layer to block redundant paths.

How to eliminate wrong answers

Option B (DNS) is wrong because DNS (Domain Name System) translates domain names to IP addresses and has no role in preventing network loops. Option C (NAT) is wrong because NAT (Network Address Translation) modifies IP addresses in packet headers for private-to-public address mapping and does not address loop prevention. Option D (DHCP) is wrong because DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses to clients and does not manage network topology or loop avoidance.

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94

MCQmedium

An office has a single shared printer connected via USB to a Windows 10 desktop. Other users in the office need to print to this printer from their own computers, which are connected to the same local network. What is the simplest way to share the printer without additional hardware?

A.Set up a print server using a Raspberry Pi

B.Enable printer sharing on the desktop and connect from other computers using the network path

C.Install the printer on each computer by connecting it via USB when needed

D.Connect the printer directly to the network switch using an Ethernet cable

AnswerB

This uses built-in Windows features, no extra hardware needed.

Why this answer

Option B is correct because Windows 10 includes built-in printer sharing via the SMB protocol, which allows the printer connected via USB to be shared over the local network without any additional hardware. Enabling printer sharing on the desktop and connecting from other computers using the network path (e.g., \\desktop-name\printer-name) is the simplest method that leverages existing network infrastructure.

Exam trap

The trap here is that candidates may overthink the solution and choose a more complex option like a Raspberry Pi print server (Option A), not realizing that Windows' built-in printer sharing is designed exactly for this scenario and requires no extra hardware.

How to eliminate wrong answers

Option A is wrong because setting up a print server using a Raspberry Pi introduces unnecessary complexity and additional hardware, which contradicts the requirement for the simplest solution without additional hardware. Option C is wrong because installing the printer on each computer by connecting it via USB when needed is impractical, disrupts workflow, and does not provide network-based shared access. Option D is wrong because connecting the printer directly to the network switch using an Ethernet cable would require the printer to have built-in network capabilities (such as a network interface or print server), which is not indicated in the scenario, and would also require additional hardware if the printer lacks such features.

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95

MCQhard

Refer to the exhibit. A technician runs ipconfig /all on a user's computer. The user can access the internet but cannot browse to any websites by domain name. What is the most likely cause?

A.DHCP is disabled on the computer.

B.The DNS server address is incorrect or not functioning for external lookups.

C.The IP address is a private address and cannot access the internet.

D.The subnet mask should be 255.255.0.0.

AnswerB

Router may not provide DNS resolution for external domains.

Why this answer

The user can access the internet (IP connectivity works) but cannot browse by domain name, which indicates that DNS resolution is failing. The `ipconfig /all` output would show a DNS server address; if that address is incorrect or the DNS server cannot perform external lookups, the computer cannot translate domain names to IP addresses, even though other network functions (like DHCP and IP routing) are working correctly.

Exam trap

The trap here is that candidates assume internet access means all network services are working, but DNS is a separate service that can fail independently of IP connectivity, and the question specifically tests whether you can isolate the symptom of name resolution failure from general connectivity.

How to eliminate wrong answers

Option A is wrong because DHCP being disabled would prevent the computer from obtaining an IP address automatically, but the user can access the internet, so the computer must have a valid IP configuration (either static or from DHCP). Option C is wrong because private IP addresses (e.g., 192.168.x.x, 10.x.x.x) can access the internet through NAT (Network Address Translation) on a router, and the user already has internet access, so the private address is not the issue. Option D is wrong because the subnet mask 255.255.255.0 is standard for a /24 network and would not prevent DNS resolution; changing it to 255.255.0.0 would likely cause routing problems but is unrelated to the symptom of failing to browse by domain name.

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96

MCQhard

Refer to the exhibit. A technician runs two ping commands. Based on the output, which of the following is the MOST likely cause?

A.The default gateway is unreachable

B.The network connection is down

C.DNS server is misconfigured

D.A firewall is blocking ICMP traffic

AnswerB

Both pings fail, indicating no network connectivity.

Why this answer

Option B is correct. The ping to 8.8.8.8 (IP) fails, but the second failure to google.com says 'Temporary failure in name resolution', indicating DNS is not resolving. However, the first ping to an IP fails completely, suggesting no connectivity at all.

But the key is that the DNS resolution failure is additional. Actually, the exhibit shows both pings fail. The ping to 8.8.8.8 fails with 100% loss, meaning no IP connectivity.

The DNS error is secondary. The most likely cause is that the network is down entirely. Option A is wrong because DNS is not the primary issue since IP ping also fails.

Option C is wrong because firewall would cause different errors. Option D is wrong because router is needed for routing.

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97

MCQmedium

A small office needs a centralized storage solution that all employees can access over the network to share files. Which type of storage should they implement?

A.NAS

B.JBOD

C.SAN

D.DAS

AnswerA

Network-Attached Storage provides file-level access over a network, ideal for small offices.

Why this answer

A NAS (Network Attached Storage) is a dedicated file-level storage device connected to a network, allowing multiple users to access and share files over standard protocols like SMB/CIFS (Windows) or NFS (Linux/Unix). This makes it the ideal centralized solution for a small office needing shared network file access without requiring a dedicated server.

Exam trap

The trap here is that candidates often confuse NAS with SAN, thinking both are network storage, but SAN requires a dedicated network and provides block-level access (like a virtual hard drive), whereas NAS provides file-level access over the existing LAN, making NAS the simpler and more cost-effective choice for file sharing.

How to eliminate wrong answers

Option B (JBOD) is wrong because JBOD (Just a Bunch Of Disks) is a method of combining multiple physical disks into a single logical volume without any network connectivity or file-sharing capabilities; it is a direct-attached storage configuration, not a network-accessible solution. Option C (SAN) is wrong because a SAN (Storage Area Network) provides block-level storage access over a dedicated high-speed network (typically Fibre Channel or iSCSI), which is more complex and expensive than needed for simple file sharing in a small office; it requires a separate server to manage file systems and is overkill for this use case. Option D (DAS) is wrong because DAS (Direct Attached Storage) connects directly to a single computer via interfaces like SATA or USB, and cannot be accessed by multiple users over the network without sharing that host computer, which defeats the purpose of a centralized network-accessible storage.

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98

Multi-Selecteasy

Which TWO of the following are common Ethernet cable categories used in local area networks?

Select 2 answers

A.Cat5e

B.USB

C.Coaxial

D.Cat6

E.HDMI

AnswersA, D

Cat5e is a standard Ethernet cable supporting up to 1 Gbps.

Why this answer

Cat5e and Cat6 are twisted-pair cables commonly used for Ethernet. Coaxial is used for cable TV, HDMI for audio/video, USB for peripherals.

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99

MCQmedium

A small business wants to set up a local network with internet access. They have a modem from the ISP and need to share the connection among five computers. Which device should they use to connect all computers to the modem and manage traffic?

A.Router

B.Hub

C.Bridge

D.Switch

AnswerD

A switch connects devices on a LAN and is ideal for sharing internet via modem.

Why this answer

A switch is the correct device because it connects multiple computers in a local network and forwards frames based on MAC addresses, allowing all five computers to share the modem's internet connection efficiently. Unlike a hub, a switch creates dedicated collision domains per port, reducing traffic collisions and improving performance. The modem provides the WAN connection, and the switch handles LAN traffic distribution among the computers.

Exam trap

The trap here is that candidates often confuse the roles of a router and a switch, assuming a router is always needed for internet sharing, but the modem already provides the internet connection and a switch handles local traffic distribution without routing between networks.

How to eliminate wrong answers

Option A is wrong because a router is used to connect different networks (e.g., LAN to WAN) and typically includes NAT and DHCP, but the question specifies the modem is already present and the need is to connect computers locally and manage traffic—a switch is sufficient for that layer 2 task. Option B is wrong because a hub operates at layer 1 and broadcasts all data to every port, causing collisions and inefficient bandwidth usage, making it unsuitable for managing traffic among five computers. Option C is wrong because a bridge connects two separate network segments and filters traffic based on MAC addresses, but it is not designed to connect multiple computers to a single modem; a switch is a multiport bridge and is the appropriate device here.

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100

MCQmedium

A user reports that they can access websites by IP address but not by domain name. Based on the exhibit, which of the following is the MOST likely cause?

A.Duplicate IP address on the network

B.Incorrect default gateway

C.Incorrect subnet mask

D.Incorrect or unreachable DNS server

AnswerD

DNS is needed for name resolution; if it's down or wrong, domains won't resolve.

Why this answer

The user can access websites by IP address but not by domain name, which indicates that IP routing and connectivity are functioning correctly. The failure to resolve domain names points directly to a DNS issue, such as an incorrect or unreachable DNS server. DNS translates human-readable domain names into IP addresses; without a working DNS server, name resolution fails while direct IP access remains unaffected.

Exam trap

The trap here is that candidates often confuse DNS failure with gateway or routing issues, but the ability to access sites by IP address proves that routing and gateway settings are correct, isolating the problem to name resolution.

How to eliminate wrong answers

Option A is wrong because a duplicate IP address would cause intermittent connectivity or address conflicts, not a selective failure of domain name resolution while IP-based access works. Option B is wrong because an incorrect default gateway would prevent traffic from leaving the local subnet entirely, making both IP and domain name access fail, not just name resolution. Option C is wrong because an incorrect subnet mask would cause communication failures with hosts outside the local subnet, affecting all external access regardless of whether an IP or domain name is used.

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101

MCQeasy

A small office has five computers connected to a switch, which is connected to a router that provides internet access. The office uses a single printer connected to one computer and shared over the network. The router has built-in DHCP and assigns IP addresses in the 192.168.0.0/24 range. Recently, the office manager added a wireless access point (WAP) to allow guests to access the internet. The WAP is connected to the switch and configured with its own DHCP server handing out addresses in the 192.168.1.0/24 range. The manager notices that some office computers are unable to access the shared printer, while others can. The computers that cannot access the printer have IP addresses in the 192.168.1.0/24 range. The printer's IP address is 192.168.0.50. What is the most likely cause of the issue?

A.The WAP's DHCP server is malfunctioning.

B.The computers with IP addresses in the 192.168.1.0/24 range are on a different subnet than the printer.

C.The switch port for the printer is faulty.

D.The printer is not powered on.

AnswerB

Different subnets require a router to communicate.

Why this answer

The computers with IP addresses in the 192.168.1.0/24 range are on a different subnet than the printer, which has an IP address of 192.168.0.50. Without a router configured to route traffic between these two subnets, devices on the 192.168.1.0/24 network cannot communicate with devices on the 192.168.0.0/24 network. Since the WAP is acting as a separate DHCP server and is not routing between the subnets, the printer remains unreachable from the guest network.

Exam trap

The trap here is that candidates may assume all devices connected to the same switch are on the same network, overlooking that separate DHCP servers create distinct subnets that require a router to communicate.

How to eliminate wrong answers

Option A is wrong because the WAP's DHCP server is functioning correctly by assigning IP addresses in the 192.168.1.0/24 range; the issue is not a malfunction but a subnet mismatch. Option C is wrong because a faulty switch port would affect all devices connected to that port, not selectively impact only computers on a specific subnet. Option D is wrong because if the printer were not powered on, no computers would be able to access it, but the question states that some office computers (those on the 192.168.0.0/24 subnet) can access the printer.

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102

MCQmedium

Refer to the exhibit. A user is able to browse the internet using the Ethernet connection but not the Wi-Fi. What is the most likely cause?

A.The Wi-Fi adapter is not connected to any network

B.The Wi-Fi adapter is disabled

C.The DNS suffix is missing

D.The default gateway is incorrect

AnswerA

'Media disconnected' indicates no active wireless connection.

Why this answer

The exhibit shows that the Ethernet interface has an IP address (192.168.1.114) and is connected to the internet, while the Wi-Fi interface shows 'Not connected' with no IP address assigned. Since the user can browse the internet via Ethernet but not Wi-Fi, the most likely cause is that the Wi-Fi adapter is not connected to any network, meaning it has not associated with a wireless SSID or obtained an IP address via DHCP.

Exam trap

The trap here is that candidates may confuse 'Not connected' with a disabled adapter or a configuration issue like a missing DNS suffix, but the exhibit clearly shows the Wi-Fi adapter is enabled yet has no IP address, pointing to a lack of network association.

How to eliminate wrong answers

Option B is wrong because if the Wi-Fi adapter were disabled, it would typically show a status like 'Disabled' or 'Not operational' in the network settings, not 'Not connected' — the adapter is enabled but not associated with a network. Option C is wrong because a missing DNS suffix would not prevent the Wi-Fi adapter from obtaining an IP address or connecting to a network; it would only affect name resolution, and the user can already browse via Ethernet, indicating DNS is working. Option D is wrong because an incorrect default gateway would still allow the adapter to show a connected status with an IP address, but the user would be unable to reach external networks — the exhibit shows the Wi-Fi adapter has no IP address at all, so the gateway is irrelevant.

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103

Multi-Selectmedium

Which TWO of the following are benefits of virtualization in a data center?

Select 2 answers

A.Improved disaster recovery capabilities

B.Increased hardware reliability

C.Reduced hardware footprint

D.Enhanced physical security

E.Simplified network configuration

AnswersA, C

VMs can be backed up and migrated easily.

Why this answer

Virtualization enables rapid restoration of virtual machines (VMs) from snapshots or backups, often within minutes, regardless of underlying hardware failures. This decoupling of the OS from physical hardware allows VMs to be migrated or recovered on different hosts, significantly improving recovery time objectives (RTOs) and recovery point objectives (RPOs) compared to physical server recovery.

Exam trap

Cisco often tests the misconception that virtualization inherently improves hardware reliability or simplifies networking, when in fact it primarily improves resource utilization and disaster recovery capabilities.

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104

MCQmedium

A small business wants to set up a wireless network for employees and guests. The owners are concerned about unauthorized access. Which of the following security measures would be MOST effective to prevent outsiders from connecting?

A.Enable MAC address filtering

B.Disable SSID broadcast

C.Disable DHCP on the router

D.Use WPA2 encryption with a strong passphrase

AnswerD

WPA2 provides strong encryption and authentication.

Why this answer

Option B is correct because WPA2 encryption with a strong password is the standard for securing Wi-Fi. Option A is wrong because SSID broadcast hiding is easily bypassed. Option C is wrong because MAC filtering can be spoofed.

Option D is wrong while disabling DHCP may hinder but not prevent connection; static IP can be guessed.

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105

MCQhard

What is the most likely reason PC1 cannot ping PC2?

A.The default gateway is incorrect on PC1

B.A firewall on PC2 is blocking ICMP echo requests

C.PC2's network interface is disabled

D.The switch port for PC2 is faulty

AnswerB

Firewalls often block ping by default while allowing other traffic.

Why this answer

Option C is correct because a firewall on PC2 can be configured to block ICMP echo requests (ping) while allowing other traffic. Option A is incorrect because if PC2's NIC were disabled, PC1 would not be able to communicate with PC2 at all, and the ping would fail, but it's not the most likely scenario given that PC1 can ping PC3 (indicating the switch and network are functioning). Option B is incorrect because a default gateway is only required for off-subnet communication; PC1 and PC2 are on the same subnet.

Option D is incorrect because if the switch port for PC2 were faulty, PC2 would have no network connectivity, and PC1 would fail to reach it for any service, not just ping.

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106

Multi-Selecthard

Which TWO of the following are effective methods to help secure a wireless network from unauthorized access?

Select 2 answers

A.Enabling WPA2 encryption

B.Enabling WEP encryption

C.Disabling the firewall

D.Enabling MAC address filtering

E.Broadcasting the SSID

AnswersA, D

WPA2 provides strong encryption to protect data.

Why this answer

WPA2 encryption and MAC filtering are effective. WEP is weak and easily broken, broadcasting SSID makes the network visible, and disabling the firewall reduces security.

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107

MCQmedium

A company is setting up a new branch office. The network administrator needs to connect 20 computers and 2 network printers to the local network. The branch also needs a connection to the internet via a cable modem. The administrator has a 24-port switch and a wireless router. The cable modem is already provided by the ISP. Which configuration should the administrator use?

A.Connect the cable modem to the wireless router's WAN port, then connect the switch to one of the router's LAN ports, and connect all devices to the switch

B.Connect the cable modem to the switch, and then connect the wireless router to the switch using its WAN port

C.Connect the cable modem directly to the switch, then connect all devices to the switch

D.Connect the cable modem to one computer, then bridge that computer's network connection to the switch

AnswerA

This allows the router to handle internet sharing and local network management.

Why this answer

Option A is correct because the wireless router must be placed between the cable modem and the switch to perform Network Address Translation (NAT) and routing. The cable modem connects to the router's WAN port, which obtains a public IP from the ISP. The router then provides private IP addresses via DHCP to the switch and all connected devices, enabling internet access for the 20 computers and 2 printers through a single public IP.

Exam trap

The trap here is that candidates often confuse the roles of a switch and a router, assuming a switch can provide internet access to multiple devices directly from a modem, when in fact a router is required for NAT and IP address sharing.

How to eliminate wrong answers

Option B is wrong because connecting the cable modem directly to the switch would bypass the router's NAT and routing functions, meaning the switch would only forward the raw public IP traffic, which cannot be shared among multiple devices without a router. Option C is wrong because a switch operates at Layer 2 and cannot perform NAT or routing; connecting the cable modem directly to the switch would provide internet access to only one device (the one that obtains the public IP via DHCP), leaving the rest without connectivity. Option D is wrong because bridging a computer's connection to the switch creates a single point of failure, requires the computer to be always on, and introduces security and performance issues; it is not a standard or reliable method for a branch office network.

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108

MCQmedium

A user reports that they cannot print to a network printer. Other users can print to the same printer. Which of the following should the technician check FIRST?

A.The printer's IP address

B.The printer driver on the user's computer

C.The network switch port

D.The printer's power cable

AnswerB

A misconfigured or missing driver can prevent printing.

Why this answer

Since other users can print to the same network printer, the printer itself, its network connectivity, and its IP address are all functioning correctly. The issue is isolated to the single user's computer, making the printer driver on that machine the most likely cause. A corrupted, missing, or incorrect driver would prevent that specific user from sending print jobs while others remain unaffected.

Exam trap

The trap here is that candidates often jump to network-level troubleshooting (IP address, switch port) because the issue involves a network printer, but the symptom of 'other users can print' immediately isolates the problem to the local client, making the driver the logical first check.

How to eliminate wrong answers

Option A is wrong because the printer's IP address is already working for other users; checking it first would be redundant and would not resolve a user-specific issue. Option C is wrong because the network switch port is functioning properly, as evidenced by other users successfully printing to the same printer through the same network path. Option D is wrong because the printer's power cable is clearly supplying power (the printer is online and accepting jobs from other users), so checking it would waste time.

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109

MCQhard

A technician is troubleshooting a network where users in one department cannot reach a web server in another subnet. The technician confirms the server is running and the switch ports are up. Which of the following should be checked NEXT?

A.DHCP server scope

B.Firewall rules on the server

C.DNS server settings

D.Router configuration

AnswerD

The router routes between subnets; misconfiguration can block traffic.

Why this answer

Since the server is running and switch ports are up, the issue is likely at Layer 3 (network layer). The router is responsible for forwarding traffic between subnets, so a misconfigured router (e.g., missing static route, incorrect ACL, or routing protocol issue) would prevent inter-subnet communication. Checking the router configuration is the logical next step to verify that routing is properly set up for the destination subnet.

Exam trap

The trap here is that candidates often jump to DNS or firewall issues first, but the scenario explicitly describes a subnet-to-subnet reachability problem, which directly points to Layer 3 routing as the root cause.

How to eliminate wrong answers

Option A is wrong because the DHCP server scope only affects IP address assignment within a subnet; if users already have IP addresses and can reach other resources, DHCP is not the cause of a specific inter-subnet failure. Option B is wrong because firewall rules on the server would block all traffic to the server, but the technician already confirmed the server is running and reachable from its own subnet; the issue is routing between subnets, not server-level filtering. Option C is wrong because DNS server settings affect name resolution, not IP-level connectivity; if the users can ping the web server's IP address but not its hostname, DNS would be suspect, but the problem states they cannot reach the server at all, indicating a routing issue.

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110

MCQmedium

A company wants to implement a backup solution that allows for quick restoration of individual files. Which backup type should be used?

A.System image backup

B.Differential backup

C.Full backup

D.Incremental backup

AnswerC

Full backup contains all files and allows individual file restoration.

Why this answer

A full backup creates a complete copy of all selected data, allowing any individual file to be restored directly from that single backup set without needing to process other backup sets. This makes it the simplest and fastest option for restoring specific files, as no additional dependencies or chain reconstructions are required.

Exam trap

The trap here is that candidates often choose differential or incremental backups because they are faster to create, but the question specifically asks for quick restoration of individual files, which is best achieved with a full backup due to its independence and simplicity.

How to eliminate wrong answers

Option A is wrong because a system image backup captures the entire operating system, boot files, and system state, which is designed for bare-metal recovery of the whole machine rather than quick restoration of individual files. Option B is wrong because a differential backup only stores changes made since the last full backup, so restoring a single file requires both the last full backup and the latest differential backup, adding complexity and time. Option D is wrong because an incremental backup stores only changes since the last backup (full or incremental), creating a chain of dependent backup sets that must be fully processed in order to restore a single file, which is slower and more error-prone for individual file recovery.

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111

MCQmedium

A company wants to ensure data redundancy in case of a single hard drive failure. Which RAID level should they use?

A.RAID 0

B.RAID 5

C.JBOD

D.RAID 1

AnswerD

RAID 1 mirrors data across two drives, providing fault tolerance for a single drive failure.

Why this answer

RAID 1 (mirroring) writes identical data to two or more drives simultaneously, providing full data redundancy. If one drive fails, the system continues to operate using the mirrored copy, ensuring no data loss and minimal downtime. This makes RAID 1 the correct choice for protecting against a single hard drive failure.

Exam trap

The trap here is that candidates often confuse RAID 5 as the 'standard' redundancy option due to its efficiency, but the question specifically asks for redundancy in case of a single drive failure with no mention of capacity optimization, making RAID 1 the simplest and most direct answer.

How to eliminate wrong answers

Option A (RAID 0) is wrong because it stripes data across drives without any parity or mirroring, offering no fault tolerance; a single drive failure results in complete data loss. Option B (RAID 5) is wrong because while it provides redundancy through distributed parity and can survive a single drive failure, it requires a minimum of three drives and uses parity calculations, making it more complex and slower for write operations than the simple mirroring of RAID 1. Option C (JBOD) is wrong because it simply concatenates disks into a single logical volume without any redundancy; failure of one drive causes loss of only that drive's data, but the array may still be partially functional, not providing the guaranteed redundancy the question asks for.

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112

Matchingmedium

Match each database concept to its description.

Drag a concept onto its matching description — or click a concept then click the description.

Concepts

Matches

Uniquely identifies each record

Links two tables together

Speeds up data retrieval

Requests data from a database

Why these pairings

These are fundamental database concepts.

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113

MCQhard

A small business has 20 employees using a mix of wired and wireless devices. The network uses a single router with built-in 4-port switch and Wi-Fi. Recently, employees have reported intermittent connectivity drops, especially during peak hours. The technician notices that the router's CPU usage is consistently at 90% or higher. The business cannot afford to replace the router immediately. Which of the following actions would BEST improve the situation without purchasing new hardware?

A.Disable Quality of Service (QoS) settings

B.Disable the Wi-Fi network and require all devices to connect via Ethernet

C.Assign static IP addresses to all devices

D.Configure VLANs to separate wired and wireless traffic

AnswerD

VLANs reduce broadcast domains and can lower CPU load.

Why this answer

Configuring VLANs separates wired and wireless traffic into distinct broadcast domains, reducing the amount of broadcast traffic and collisions that the router's CPU must process. This lowers CPU overhead, which directly addresses the 90% CPU usage causing intermittent drops, without requiring new hardware.

Exam trap

The trap here is that candidates often think disabling QoS or switching to wired-only will reduce CPU load, but they overlook that VLAN segmentation directly reduces broadcast processing overhead, which is the primary CPU consumer in a mixed wired/wireless environment.

How to eliminate wrong answers

Option A is wrong because disabling QoS would remove traffic prioritization, potentially increasing CPU load as the router processes more unmanaged traffic, worsening the problem. Option B is wrong because forcing all 20 devices onto the 4-port switch would exceed port capacity, requiring additional switches or causing physical connectivity issues, and does not reduce CPU load from routing overhead. Option C is wrong because assigning static IPs eliminates DHCP server load but does not reduce broadcast traffic or CPU usage from routing/switching decisions, so it provides minimal benefit for high CPU utilization.

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114

Multi-Selectmedium

Which TWO of the following are characteristics of a client-server network? (Choose two.)

Select 2 answers

A.Clients can be desktop computers, laptops, or smartphones

B.There is a centralized server that manages resources

C.All devices are directly connected to each other

D.Every device can act as both client and server

E.Each device has equal authority and control

AnswersA, B

Clients are often end-user devices.

Why this answer

Option A is correct because client-server networks are designed to support a variety of client devices, including desktop computers, laptops, and smartphones, which all connect to a centralized server to request resources or services. Option B is correct because the defining characteristic of a client-server network is the presence of a centralized server that manages resources, such as file storage, authentication, or database access, and controls access to those resources for all clients.

Exam trap

The trap here is that candidates often confuse the client-server model with peer-to-peer networks, mistakenly thinking that all devices in a client-server network can act as both client and server or have equal authority, which is a direct characteristic of P2P networks, not client-server.

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115

MCQmedium

A small office needs a network that is easy to set up and allows devices to connect without wires. The office has a single internet connection and about 15 devices. Which of the following is the BEST choice?

A.Network hub

B.PoE switch

C.Wireless router with integrated switch

D.Cable modem

AnswerC

Provides Wi-Fi, routing, and switching for 15 devices.

Why this answer

A wireless router with an integrated switch combines a router, a wireless access point, and a multi-port Ethernet switch into a single device. This allows the office to connect all 15 devices wirelessly while sharing the single internet connection, and the integrated switch provides wired ports for devices that may need a stable connection. It is the simplest and most cost-effective solution for a small office requiring easy setup and wireless connectivity.

Exam trap

The trap here is that candidates often confuse a cable modem with a router, thinking a modem alone can create a local network, but a modem only bridges the ISP connection and lacks routing, switching, and wireless capabilities.

How to eliminate wrong answers

Option A is wrong because a network hub is a legacy device that operates at Layer 1 (physical layer), forwarding all traffic to all ports, which creates collisions and severely degrades performance with 15 devices; it does not provide wireless connectivity. Option B is wrong because a PoE (Power over Ethernet) switch provides power and data over Ethernet cables to devices like IP cameras or phones, but it does not include wireless functionality, so devices would still need wired connections. Option D is wrong because a cable modem only modulates/demodulates signals from the ISP and provides a single Ethernet port; it cannot route traffic between devices or provide wireless access, so it cannot create a local network for 15 devices.

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116

MCQeasy

A user wants to access a website but types the wrong URL. Which technology resolves domain names to IP addresses?

AnswerC

DNS resolves domain names to IP addresses.

Why this answer

DNS (Domain Name System) is the technology that translates human-readable domain names (like www.example.com) into machine-readable IP addresses (like 192.0.2.1). When a user types a wrong URL, the browser still sends a DNS query to resolve the domain portion of the URL; if the domain is valid but the path is wrong, DNS resolves correctly, but if the domain itself is mistyped, DNS may fail or redirect to a different IP. This resolution is essential for locating the web server on the internet.

Exam trap

The trap here is that candidates often confuse DNS with DHCP because both involve network configuration, but DHCP assigns IP addresses dynamically while DNS resolves names to IPs; Cisco tests this distinction by pairing them as distractors.

How to eliminate wrong answers

Option A is wrong because HTTP (Hypertext Transfer Protocol) is an application-layer protocol used for transferring web content, not for resolving domain names to IP addresses. Option B is wrong because NAT (Network Address Translation) translates private IP addresses to public IP addresses for routing, not domain name resolution. Option D is wrong because DHCP (Dynamic Host Configuration Protocol) automatically assigns IP addresses and other network configuration parameters to devices, but does not perform domain-to-IP resolution.

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117

MCQmedium

A user reports that their laptop cannot connect to the corporate Wi-Fi. Other devices in the same area work fine. The network technician checks the laptop and sees that the wireless adapter is enabled and shows available networks, but the connection attempt to the corporate SSID fails with an authentication error. Which of the following is the MOST likely cause?

A.The MAC address is filtered on the access point

B.The DHCP lease has expired

C.The pre-shared key is incorrect

D.The wireless adapter is disabled in Device Manager

AnswerC

An incorrect PSK causes authentication failure while the network is still visible.

Why this answer

The authentication error specifically indicates that the laptop failed to verify its credentials with the access point. Since the wireless adapter is enabled and the SSID is visible, the most common cause is an incorrect pre-shared key (PSK), which prevents the 4-way handshake in WPA2/WPA3 from completing successfully.

Exam trap

The trap here is that candidates confuse an authentication error with a connectivity issue like DHCP failure, but authentication errors are strictly tied to credential validation during the 802.11 handshake, not IP-layer problems.

How to eliminate wrong answers

Option A is wrong because MAC address filtering would block the association entirely, not cause an authentication error after the SSID is visible. Option B is wrong because an expired DHCP lease would prevent obtaining an IP address, but the authentication error occurs at layer 2 before DHCP is involved. Option D is wrong because the wireless adapter is explicitly stated as enabled and showing available networks, so it cannot be disabled in Device Manager.

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118

MCQhard

A server in a data center is running a critical application. The server is connected to a managed switch via two network cables for redundancy (link aggregation). Recently, the server experienced intermittent connectivity issues. The network logs show that every few hours, one of the links goes down and then comes back up within a minute. The other link remains up. The server's team reports no errors in the server logs. What is the most likely cause of this issue?

A.The switch's uplink port is faulty

B.The switch is experiencing broadcast storms

C.The network cable is poorly terminated

D.The server's network adapter is overheating

AnswerC

Poor termination can cause intermittent connectivity on a single cable.

Why this answer

Option C is correct because a poorly terminated cable can cause intermittent physical-layer issues such as impedance mismatches or partial breaks, which lead to link flaps (link down/up events) without generating errors in the server's operating system logs. In a link aggregation group (LAG) using LACP or static aggregation, a single faulty cable will cause only that link to drop, while the other link continues to carry traffic, matching the described symptom of one link cycling every few hours.

Exam trap

The trap here is that candidates often assume software or configuration issues (like broadcast storms or adapter overheating) when the symptom of a single link flapping in a LAG points directly to a physical-layer problem with that specific cable, not a systemic or hardware-wide fault.

How to eliminate wrong answers

Option A is wrong because a faulty switch uplink port would affect all traffic passing through that uplink, not just one specific link in the aggregation group, and would likely cause connectivity loss for multiple devices or the entire switch. Option B is wrong because a broadcast storm would overwhelm the network with broadcast frames, causing both links to be saturated and the server to experience general connectivity loss, not just one link flapping while the other remains stable. Option D is wrong because an overheating network adapter typically causes the entire adapter to fail or throttle, affecting both links simultaneously (since they share the same physical adapter), and would likely produce temperature-related errors in the server logs.

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119

MCQeasy

Refer to the exhibit. A user cannot access the internet. What does this output indicate?

A.The default gateway cannot reach the remote network

B.The user's IP address is invalid

C.The DNS server is down

D.The local network cable is unplugged

AnswerA

The gateway reports destination unreachable, indicating a routing problem.

Why this answer

The output shows a successful ping to the default gateway (192.168.1.1) but a failed ping to a remote IP (8.8.8.8). This indicates that the user's local network connectivity is intact, but the default gateway cannot forward traffic to the remote network, likely due to a missing or incorrect route on the gateway or an upstream connectivity issue.

Exam trap

The trap here is that candidates assume a successful ping to the default gateway means full internet connectivity, but the question tests the understanding that the gateway itself may not have a route to external networks.

How to eliminate wrong answers

Option B is wrong because the user's IP address is valid, as evidenced by the successful ping to the default gateway, which requires a properly configured IP address and subnet mask. Option C is wrong because the DNS server being down would not affect a ping to an IP address (8.8.8.8), which bypasses DNS resolution entirely. Option D is wrong because if the local network cable were unplugged, the ping to the default gateway would fail, not succeed.

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