Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A technician is troubleshooting a user's workstation that experiences intermittent network disconnections. The technician has replaced the network interface card (NIC) and the Ethernet cable with known-good components. The switch port link light remains solid when the connection is up, but the problem still occurs. Upon inspecting the switch's interface statistics, the technician notices a high number of CRC (Cyclic Redundancy Check) errors on that port. Which of the following is the MOST likely cause of the issue?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
Electromagnetic interference (EMI) from nearby power cables or lighting fixtures affecting the Ethernet cable
EMI can induce noise in copper Ethernet cables, causing data corruption detected as CRC errors. Since the cable and NIC have been replaced, the physical environment is the likely culprit. Running the cable away from sources of EMI should resolve the issue.
B
Distractor review
The switch port is faulty and needs to be replaced
A faulty switch port could cause CRC errors, but it is less likely after verifying the link light is solid and the port works initially. EMI is a more common cause, and the switch port would not be the first thing to suspect after replacing the client-side components.
C
Distractor review
An incorrect VLAN assignment on the switch port is causing mismatched network traffic
Incorrect VLAN assignment would typically cause connectivity issues (e.g., cannot reach default gateway) or broadcast domain isolation, but it would not cause CRC errors. CRC errors are physical/link layer issues, not logical configuration problems.
D
Distractor review
A duplex mismatch between the workstation and the switch
Duplex mismatch can cause CRC errors and poor performance, but it is less likely when both devices are set to auto-negotiate. The technician replaced the NIC and cable, and auto-negotiation usually resolves duplex settings. EMI is a more probable cause given the intermittent nature and high CRC count.
Common exam trap
Common exam trap: an active trunk can still block the VLAN you need
A trunk being up does not prove every VLAN is crossing it. Check allowed VLAN lists, native VLAN mismatch, VLAN existence and access-port assignment.
Technical deep dive
How to think about this question
VLAN questions usually combine access-port and trunking clues. The key is to identify whether the issue is local to one switchport, caused by the trunk, or caused by the VLAN not existing where it needs to exist.
KKey Concepts to Remember
- Access ports place end devices into a single VLAN.
- Trunk ports carry multiple VLANs between switches.
- Allowed VLAN lists decide which VLANs can cross a trunk.
- Native VLAN mismatch can create confusing symptoms.
TExam Day Tips
- Use show vlan brief to verify access VLANs.
- Use show interfaces trunk to verify trunk state and allowed VLANs.
- Do not treat every same-VLAN issue as a routing problem.
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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
Question 1
A user reports intermittent network connectivity on a desktop computer. The technician observes that the Ethernet link light on the NIC turns off for a few seconds and then turns back on. The cable passes a wiremap test, the switch port is verified good with another device, and the NIC driver is updated. The issue occurs more frequently when the computer's case fan runs at high speed. Which of the following is the MOST likely cause?
Question 2
A workstation is unable to connect to the internet. The technician runs the 'ipconfig' command and sees the IPv4 address is 169.254.15.200 with a subnet mask of 255.255.0.0. The workstation can ping other devices on the local subnet but cannot ping the default gateway or any external addresses. Which TWO actions should the technician take to resolve this issue? (Select two.)
Question 3
A workstation is connected to a managed switch. It obtains a valid IP address (192.168.10.50) from the DHCP server, but it cannot ping the default gateway (192.168.10.1). The link light on both the workstation NIC and the switch port are solid green. Other workstations on the same switch CAN ping the default gateway successfully. The technician accesses the switch management interface and finds that the workstation's port is configured as an access port on VLAN 10. The default gateway is located on VLAN 20. An inter-VLAN router is configured but not explicitly allowing VLAN 10 access to VLAN 20. Which of the following is the MOST likely cause of the problem?
Question 4
A company develops a web application that relies on a custom library available only for a specific Linux distribution. They want to deploy the application in the cloud with minimal administrative overhead, but they need full control over the software stack, including the ability to install the custom library and configure the web server. Which cloud service model BEST meets these requirements?
Question 5
A company has a legacy virtual machine running on a deprecated hypervisor (Hyper-V). They want to migrate this VM to a new hypervisor (VMware vSphere) hosted in a private cloud while preserving the VM's configuration, installed applications, and data. The migration must be performed with minimal downtime. Which of the following methods is MOST appropriate?
Question 6
A company hosts a critical database on a virtual machine in a public cloud. The database requires persistent storage that must be retained even if the VM is terminated. The storage must also be accessible from multiple VMs simultaneously for a future high-availability configuration. Which type of cloud storage BEST meets these requirements?
FAQ
Questions learners often ask
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: Electromagnetic interference (EMI) from nearby power cables or lighting fixtures affecting the Ethernet cable — CRC errors indicate data corruption at the data link layer, typically caused by physical layer issues such as electromagnetic interference (EMI) from nearby power cables or fluorescent lights. Since the cable and NIC have been replaced, the issue likely originates from the environment or the cable's path. A duplex mismatch can also cause CRC errors, but modern switches and NICs auto-negotiate by default. A faulty switch port is possible, but EMI is a more common cause after hardware replacement. The VLAN configuration would not cause CRC errors.
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.
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