A technician is configuring a small office network with a managed switch and a router that supports inter-VLAN routing. A workstation on VLAN 10 (192.168.10.0/24) can ping other workstations on VLAN 10 but cannot ping a server on VLAN 20 (192.168.20.0/24). The switch has a trunk port connecting to the router, and the trunk is configured to allow VLANs 10 and 20. The workstation's default gateway is set to 192.168.10.1. The server's default gateway is set to 192.168.20.1. Which of the following is the MOST likely cause of the problem?
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.
Best answer
A. The router's subinterface for VLAN 20 is not configured or is incorrectly configured.
Without a properly configured subinterface for VLAN 20, the router cannot route packets to that VLAN, causing the workstation to be unable to reach the server.
Distractor review
B. The workstation's firewall is blocking ICMP echo requests.
A local firewall might block pings, but the workstation can ping other devices on VLAN 10, indicating ICMP is not generally blocked. Moreover, the issue is cross-VLAN, implicating routing, not the endpoint firewall.
Distractor review
C. The switch port connecting the router is configured as an access port on VLAN 1.
If the router port were an access port, only VLAN 1 traffic would pass, and the workstation on VLAN 10 would not even reach its default gateway. The problem description implies local VLAN 10 communication works, so the trunk must be operational.
Distractor review
D. The server's default gateway is set to 192.168.20.254.
The server's default gateway is correctly stated as 192.168.20.1 in the question. If it were 192.168.20.254, the server could not reply to traffic from outside its subnet, but the initial failure is from the workstation to the server, and the workstation's gateway is correctly set.
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: A. The router's subinterface for VLAN 20 is not configured or is incorrectly configured. — For inter-VLAN routing to work, the router must have a subinterface configured for each VLAN with a corresponding IP address that serves as the default gateway for that VLAN. If the subinterface for VLAN 20 is missing or misconfigured, the router cannot route traffic to that VLAN. The workstation's firewall could block ICMP, but that would not explain why pinging the server fails while other local hosts are reachable. The switch port connecting to the router must be a trunk; if it were an access port, only one VLAN would be allowed. The server's default gateway is correctly set to 192.168.20.1.
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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