Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A network technician configures a managed switch with two VLANs: VLAN 10 (Marketing: 192.168.10.0/24) and VLAN 20 (Engineering: 192.168.20.0/24). The switch is connected to a router via a single trunk port. The router has subinterfaces configured: G0/0.10 with IP 192.168.10.1/24 and G0/0.20 with IP 192.168.20.1/24. A workstation in Marketing can ping its own default gateway (192.168.10.1) but cannot ping the Engineering gateway (192.168.20.1). Which of the following is the MOST likely cause?
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 G0/0.20 is not configured with the correct encapsulation
If the encapsulation were wrong, the router might not properly interpret VLAN tags, but the issue is more fundamental: the switch port is not sending VLAN 20 traffic to the router at all. Encapsulation issues are possible but less likely given the symptom of being unable to reach the other VLAN gateway.
B
Best answer
The switch port connecting to the router is configured as an access port in VLAN 10
Correct. An access port only carries traffic for a single VLAN. In this case, the switch port is only passing VLAN 10 traffic, so the router cannot receive or send VLAN 20 frames. The port should be changed to a trunk port allowing VLANs 10 and 20.
C
Distractor review
The workstation in Marketing has an incorrect subnet mask
If the workstation had an incorrect subnet mask, it might not know how to reach the Engineering subnet, but the ping to its own gateway works, indicating the IP configuration is correct for its local subnet. The problem is at the switch-router link.
D
Distractor review
The routing table on the router does not have routes for the Engineering subnet
The router's subinterfaces are directly connected networks, so the routing table would include both 192.168.10.0/24 and 192.168.20.0/24 if the subinterfaces are up. However, if the switch port is not trunking, the subinterface for VLAN 20 might be down, so a route might not exist. But the root cause is the switch port configuration.
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 switch port connecting to the router is configured as an access port in VLAN 10 — In a router-on-a-stick configuration, the switch port connected to the router must be configured as a trunk, tagging frames with the appropriate VLAN ID as they pass between the switch and router. If the switch port is configured as an access port in a specific VLAN (e.g., VLAN 10), it will only carry traffic for that VLAN and will drop or not forward VLAN 20 traffic. The router's subinterface for VLAN 20 would not receive any frames, and thus the Marketing workstation cannot reach the Engineering gateway. The technician should configure the switch port as a trunk and allow the necessary VLANs (10 and 20).
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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