220-1101 Practice Test 20 — 15 Questions

Question 1

A technician relocates a workstation to a different office. The workstation's link light on the NIC is solid green, and the switch port link light is also solid. The workstation shows a valid IP address but cannot ping any other devices on the network, including the default gateway. The technician verifies that the IP configuration is correct and that other devices on the same switch can communicate. Which of the following is the MOST likely cause?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

The switch port is configured for a different VLAN. The link lights are solid on both the NIC and switch port, indicating Layer 1 (physical) connectivity is intact. A valid IP address but inability to ping any devices, including the gateway, while other devices on the same switch communicate normally, points to a Layer 2 segmentation issue. The most likely cause is that the switch port is configured for a different VLAN, which isolates the workstation's broadcast domain and prevents it from reaching devices outside that VLAN, including the default gateway.

Answer

The Ethernet cable is faulty

Answer

The workstation has a duplicate IP address

Answer

The subnet mask is incorrect

Question 2

A technician is troubleshooting a workstation that can access internal network resources and the internet, but users report that they cannot browse websites using domain names (e.g., www.example.com). The technician opens a command prompt and successfully pings a public IP address (8.8.8.8), but pinging www.google.com returns 'Ping request could not find host'. The workstation receives IP settings via DHCP. Which of the following is the MOST likely cause?

Accepted Answer

The DNS server addresses are not being provided by DHCP. The workstation can ping a public IP address (8.8.8.8) but cannot resolve domain names like www.google.com. This indicates that IP connectivity is working, but DNS resolution is failing. Since the workstation receives IP settings via DHCP, the most likely cause is that the DHCP server is not providing correct DNS server addresses, leaving the workstation without a valid DNS resolver.

Answer

The default gateway is misconfigured

Answer

The workstation's firewall is blocking DNS traffic

Answer

The router's NAT is misconfigured

Question 3

A user reports that their workstation can access local network shares and printers but cannot access the internet. The technician pings the default gateway (192.168.1.1) successfully. The technician pings a public DNS server (8.8.8.8) and the request times out. Which of the following is the MOST likely cause?

Accepted Answer

The router's WAN connection is not functioning. The technician can ping the default gateway (192.168.1.1) successfully, confirming that the workstation's local IP configuration and Layer 2/3 connectivity to the router are correct. However, pinging the public DNS server 8.8.8.8 times out, which indicates that traffic is reaching the router but cannot exit to the internet. This points to a failure in the router's WAN connection (e.g., the modem or ISP link), as the router itself is reachable but cannot forward packets beyond the local subnet.

Answer

Incorrect DNS server configured on the workstation

Answer

The workstation's default gateway is misconfigured

Answer

The workstation's subnet mask is incorrect

Question 4

A technician sets up a small office network using two unmanaged switches to connect 25 computers. After connecting both switches to the router, the network becomes extremely slow and many computers lose connectivity intermittently. The technician notices that the router's status lights on all ports are flashing rapidly. Which of the following is the MOST likely cause of this issue?

Accepted Answer

A broadcast storm caused by a network loop. When two unmanaged switches are connected to the same router without any loop-prevention mechanism (such as STP), broadcast frames forwarded by one switch can be received and re-forwarded by the other, creating a network loop. This causes a broadcast storm, where broadcast frames circulate endlessly, saturating the network bandwidth and causing the router's ports to flash rapidly due to the high traffic load. The resulting congestion leads to extreme slowness and intermittent connectivity loss for all devices.

Answer

A faulty router causing packet loss

Answer

DNS server misconfiguration

Answer

Incorrect DHCP scope size

Question 5

After a power outage, a desktop computer will not power on. The PSU fan does not spin, and no LEDs are lit. The technician tests the power supply with a PSU tester; all voltages are within spec. A multimeter reading at the motherboard's power button header shows 3.3V when the button is pressed. The power supply is also confirmed to work when tested in another system. What is the most likely cause?

Accepted Answer

The motherboard has failed. The motherboard has failed because the PSU passes all voltage tests and works in another system, yet the desktop shows no signs of power (no fan spin, no LEDs) when connected to this motherboard. The 3.3V reading at the power button header indicates the motherboard is receiving standby power and the button is functioning, but the motherboard is not completing the power-on sequence (pulling PS_ON# low) to start the PSU. This points to a failed motherboard, likely a short or damaged power regulation circuit.

Answer

The power supply is still faulty despite the tester showing good voltages

Answer

The power button is faulty

Answer

The BIOS has become corrupted

Question 6

A technician is assembling a new desktop PC with an AMD Ryzen processor on a B550 motherboard. After installing the CPU, cooler, RAM, graphics card, and connecting all power cables, the technician powers on the system. The case fans spin, the motherboard LEDs light up, but there is no video output and no beep codes. The technician has verified that the monitor works with another PC, the graphics card is properly seated and has its power cables connected, and the RAM is installed in the correct slots. Which of the following should the technician check NEXT?

Accepted Answer

CPU power connector (8-pin EPS) on the motherboard. The 8-pin EPS12V CPU power connector supplies dedicated power to the processor. If this connector is not plugged in, the CPU will not initialize, resulting in no video output and no beep codes, even though case fans and motherboard LEDs receive power from the 24-pin ATX connector. The B550 motherboard requires this connection for the Ryzen CPU to operate.

Answer

BIOS version compatibility with the CPU

Answer

Power supply unit wattage rating

Answer

CMOS battery voltage

Question 7

A desktop computer will not boot. When the power button is pressed, the power LED lights up briefly and then turns off. The technician suspects a possible short circuit. Which of the following is the BEST first step to isolate the issue?

Accepted Answer

Remove the motherboard and test it outside the case on a non-conductive surface. The best first step because the symptom—power LED briefly lighting then shutting off—strongly suggests a short circuit, often caused by a motherboard standoff or loose screw contacting the case. Removing the motherboard and testing it on a non-conductive surface (e.g., cardboard or the motherboard box) isolates the motherboard from the case, allowing the technician to determine if the short is due to case contact or a component-level fault. This is a standard CompTIA A+ troubleshooting step for suspected shorts before replacing parts.

Answer

Replace the power supply with a known good unit

Answer

Reseat all internal power and data cables

Answer

Install a new motherboard immediately

Question 8

A desktop computer will not boot after a thunderstorm. When powered on, the fans spin and LEDs light, but there is no POST, no beep codes, and no display. The technician has already tested the power supply with a multimeter (all voltages within specification), reseated all RAM and expansion cards, and tried a different monitor. On close inspection of the motherboard, the technician notices several electrolytic capacitors near the CPU voltage regulator module are bulging at the top with a brownish substance around their bases. Which of the following should the technician replace to resolve the issue?

Accepted Answer

Replace the motherboard.. The bulging electrolytic capacitors with brownish residue near the CPU voltage regulator module indicate physical failure, likely due to a power surge from the thunderstorm. Damaged capacitors prevent the motherboard from delivering stable voltage to the CPU, causing no POST, no beep codes, and no display even though fans and LEDs receive power. Since the power supply tested within specification and other components have been reseated, the motherboard itself is the faulty component and must be replaced.

Answer

Replace the power supply with a higher-wattage unit.

Answer

Replace the CPU with an identical or compatible model.

Answer

Replace the RAM modules with known-good units.

Question 9

A user reports that their desktop computer intermittently loses network connectivity, especially when the nearby office printer starts printing. The link light on the NIC occasionally turns off during these events. The Ethernet cable runs near a fluorescent light fixture and a power cable. The technician has already replaced the Ethernet cable with a known-good Cat6 shielded cable, but the issue persists. Which of the following should the technician do NEXT?

Accepted Answer

Ensure the Ethernet cable is not routed near sources of electromagnetic interference (EMI).. The issue persists even after replacing the cable with a known-good Cat6 shielded cable, indicating that the problem is not the cable itself but the environment. The Ethernet cable runs near a fluorescent light fixture and a power cable, both of which are common sources of electromagnetic interference (EMI). Since the link light turns off when the printer starts, the EMI from the printer or nearby sources is likely inducing noise on the cable, disrupting the signal. The next logical step is to reroute the cable away from these EMI sources, as shielding alone may not be sufficient if the interference is strong or the shield is not properly grounded.

Answer

Move the computer to a different electrical outlet.

Answer

Replace the network interface card (NIC).

Answer

Update the NIC driver from the manufacturer's website.

Question 10

A technician is setting up a small office network. The ISP provides a cable modem with a single Ethernet port. The office has 15 computers that all need internet access. The technician has a router with four LAN ports and a 24-port unmanaged switch. Which of the following is the correct way to connect the devices to provide internet access to all computers?

Accepted Answer

Connect the modem to the router's WAN port, then connect the switch to one of the router's LAN ports, and connect all computers to the switch.. The router's WAN port is designed to connect to the ISP modem for public IP assignment via DHCP, while the LAN ports provide private IP addresses to internal devices. The switch connects to a LAN port to expand the number of available ports, allowing all 15 computers to access the internet through the router's NAT and routing functions.

Answer

Connect the modem to one of the router's LAN ports, then connect the switch to another LAN port, and connect all computers to the switch.

Answer

Connect the modem directly to the switch, then connect the router to the switch, and connect all computers to the router's LAN ports.

Answer

Connect the modem to one of the switch's ports, then connect the router to another switch port, and connect all computers to the router.

Question 11

A technician is assembling a desktop computer in a new case. After installing the motherboard and connecting all components, the computer powers on but immediately shuts down after a few seconds. The technician notices that the motherboard is touching the metal case in several places and that no standoffs were installed between the motherboard and the case tray. Which of the following is the most likely cause of the shutdown?

Accepted Answer

There is a short circuit between the motherboard and the case.. When the motherboard touches the metal case without standoffs, exposed solder points or traces on the back of the board can contact the conductive case, creating an unintended electrical path. This short circuit typically triggers the power supply's overcurrent protection (OCP) or short-circuit protection (SCP), causing the system to power on briefly and then immediately shut down to prevent damage.

Answer

The CPU is overheating due to improper cooler installation.

Answer

The power supply unit is underpowered for the system.

Answer

The front panel power button is incorrectly wired.

Question 12

A technician is building a custom workstation for 3D rendering. The components include an AMD Ryzen 7 5800X CPU, a B550 motherboard (box states 'AMD Ryzen 3000 desktop ready'), two 16GB DDR4-3600 modules (on the QVL), and a dedicated GPU. The system powers on, case fans spin, and the CPU fan spins, but the motherboard’s CPU debug LED remains lit and there is no display. The technician has reseated the CPU and found no bent pins. The RAM and GPU have been verified working in another system. The PSU is a known-good 750W unit. Which of the following should the technician do NEXT?

Accepted Answer

Upgrade the motherboard BIOS using the BIOS flashback feature. The B550 motherboard is labeled 'AMD Ryzen 3000 desktop ready,' meaning its factory BIOS supports Ryzen 3000 CPUs but not Ryzen 5000 (Vermeer) CPUs like the Ryzen 7 5800X. The CPU debug LED staying lit indicates the motherboard cannot initialize the CPU, which is a classic symptom of an incompatible BIOS version. Using the BIOS flashback feature allows the technician to update the BIOS without a compatible CPU installed, enabling support for the Ryzen 5000 series.

Answer

Replace the power supply with a higher-wattage unit

Answer

Test the system with a known-working Ryzen 3000 CPU

Answer

Replace the motherboard with a newer model that officially supports Ryzen 5000

Question 13

A company hosts a web application on a single virtual machine in a public cloud IaaS environment. The application experiences intermittent slowdowns. The administrator checks the VM's performance metrics and notices that CPU and memory usage are low, but disk I/O latency spikes during the slowdowns. The cloud provider uses a shared storage system with multiple tenants. Which of the following is the MOST likely cause?

Accepted Answer

Storage performance variability due to the noisy neighbor effect. The scenario describes a shared storage system with multiple tenants, and the symptoms (low CPU/memory but high disk I/O latency spikes) point directly to the 'noisy neighbor' effect. In a multi-tenant IaaS environment, one tenant's heavy storage workload can saturate the shared storage controller or network, causing unpredictable latency for other tenants. This matches the intermittent slowdowns without local resource exhaustion.

Answer

VM throttling due to burstable CPU

Answer

Insufficient virtual RAM allocation

Answer

Network bandwidth contention

Question 14

A user accidentally drops their smartphone into a saltwater pool. They retrieve it within seconds and wipe the exterior dry. The phone is still powered on, but the screen is flickering and the touchscreen is unresponsive. Which of the following should the user do FIRST to maximize the chance of successful recovery?

Accepted Answer

Power off the phone immediately. Powering off the phone immediately (B) is the correct first step because saltwater is highly conductive and corrosive. Even after wiping the exterior, residual moisture and salt ions inside the device can cause short circuits and electrochemical corrosion that rapidly damage internal components. Cutting power stops the flow of current through the wet circuits, minimizing the risk of permanent damage and giving the user the best chance of successful recovery through proper drying.

Answer

Place the phone in a bag of uncooked rice to absorb moisture

Answer

Connect the phone to a charger to see if it will respond

Answer

Use a hair dryer on high heat to dry the phone quickly

Question 15

A network technician is configuring a router for a small office. The office has two subnets: 192.168.1.0/24 for staff and 192.168.2.0/24 for guests. Staff can access the internet, but guests cannot. The technician confirms that both subnets have a default route to the router's WAN IP. The router has an ACL applied to the guest VLAN interface that denies all traffic to the WAN interface. What should the technician change to allow guests internet access?

Accepted Answer

Configure NAT for the guest subnet. The ACL on the guest VLAN interface blocks traffic to the WAN interface, but without NAT (Network Address Translation), the router would not translate the private guest IP addresses (192.168.2.0/24) to a public IP for internet access. Even if the ACL were removed or modified, the router would still drop packets from the guest subnet destined for the internet because it lacks a NAT rule to translate the source address. Therefore, configuring NAT for the guest subnet enables outbound internet access by translating private addresses to the router's WAN IP.

Answer

Remove the ACL from the guest VLAN interface

Answer

Add a permit statement for the guest subnet to the ACL

Answer

Change the guest subnet to 192.168.1.0/24