Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A small office network has two managed switches, Switch A and Switch B, connected via a trunk link. Switch A has VLAN 10 (192.168.10.0/24) and VLAN 20 (192.168.20.0/24) configured. Switch B has only VLAN 10 configured. A router-on-a-stick is connected to Switch A and performs inter-VLAN routing. A workstation connected to an access port on Switch B in VLAN 10 can ping other devices in VLAN 10 on both switches, but it cannot ping a server in VLAN 20 that is connected to Switch A. The trunk port on Switch B is configured to allow all VLANs. Which of the following is the MOST likely cause of this 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
Distractor review
The router's subinterface for VLAN 20 has an incorrect IP address or subnet mask.
If the router's subinterface for VLAN 20 were misconfigured, the server in VLAN 20 would likely be unreachable from any device, including those on Switch A. The problem is isolated to devices coming from Switch B, pointing to an issue on the trunk between the switches.
B
Best answer
The trunk port on Switch A is not configured to allow VLAN 20 traffic.
The trunk port on Switch A must explicitly allow VLAN 20 frames to pass. If it does not allow VLAN 20, the router never receives the inter-VLAN traffic from the workstation, and the server in VLAN 20 never receives the reply traffic. This is the most likely cause given that VLAN 10 traffic works across both switches.
C
Distractor review
The workstation's default gateway is set incorrectly.
The workstation can ping other devices in VLAN 10 on both switches, which typically requires the default gateway to be correctly configured. Inter-VLAN routing relies on the gateway, but if the workstation could reach devices in VLAN 10 across switches, the gateway is likely functional.
D
Distractor review
The switchport mode on Switch B's trunk port is set to access mode.
If Switch B's trunk port were in access mode, it would not allow VLAN 10 traffic across the trunk, but the workstation can communicate with VLAN 10 devices on Switch A, indicating the trunk is functioning for VLAN 10. Access mode would strip all VLAN tagging and cause broader connectivity failures.
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: The trunk port on Switch A is not configured to allow VLAN 20 traffic. — For the workstation on Switch B to reach a server in VLAN 20 on Switch A, traffic must travel from Switch B to Switch A via the trunk, then from Switch A to the router for inter-VLAN routing, and back. If the trunk port on Switch A is not configured to allow VLAN 20, traffic from VLAN 10 destined for VLAN 20 will be dropped when it reaches Switch A's trunk port, preventing communication. The workstation's default gateway (often the router's VLAN 10 interface) is likely correct because it can communicate within VLAN 10. The router's subinterface for VLAN 20 is probably correct if the server in VLAN 20 works with other devices. The trunk mode on Switch B is likely correct as it allows all VLANs.
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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