A technician is troubleshooting a workstation that lost network connectivity after a lightning storm. The workstation's Ethernet link light on both the NIC and the switch port is solid, but the workstation cannot access any network resources. The technician can ping 127.0.0.1 successfully. When pinging the default gateway (192.168.1.1), the request times out. The technician connects a known-good laptop to the same switch port and cable, and the laptop accesses the network normally. Which of the following is the MOST likely cause?

The workstation's IP address is statically configured with an incorrect subnet mask.

While an incorrect subnet mask could prevent pinging the default gateway, the technician did not verify the IP settings. However, the fact that a known-good laptop works on the same port suggests that the network configuration on the workstation is likely incorrect. But a static IP with wrong mask would not cause the exact symptom described (link lights on, successful loopback). Additionally, the scenario implies the workstation was working before the storm, so configuration change is less likely than a hardware issue.

The switch port is configured with the incorrect VLAN, but the link light remains on because the switch port is up.

If the switch port had an incorrect VLAN, the workstation might not be able to communicate with the default gateway. However, the known-good laptop worked on the same port, which indicates the port configuration is correct. The laptop's success proves the VLAN assignment is fine.

The workstation's network cable is faulty and only passes link pulses but not data frames.

If the cable were faulty in a way that prevented data transmission, the link light might still be solid, but the known-good laptop would also fail. Since the laptop worked, the cable is functional for data. The issue is specific to the workstation's NIC.

What does this 220-1101 question test?

Access ports place end devices into a single VLAN.

What is the correct answer to this question?

The correct answer is: The lightning storm damaged the NIC, causing it to fail at the data link layer while maintaining a physical link. — The link lights being solid indicate a physical layer (Layer 1) connection is established. The fact that a known-good laptop works on the same port and cable rules out issues with the switch port, cable, or DHCP server. Since the technician can ping loopback (127.0.0.1), the TCP/IP stack on the workstation is functional. The failure to ping the default gateway suggests that the NIC is not properly handling unicast traffic or there is a data link layer issue. A common issue after a power surge is damage to the NIC that prevents it from handling Ethernet frames correctly, even though the link is established. The NIC may have been partially damaged by the lightning storm, causing it to fail to transmit or receive data frames despite maintaining a carrier signal. This is a known failure mode: the PHY chip is damaged but still able to detect link. The technician should replace the NIC.

What should I do if I get this 220-1101 question wrong?

Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.