A technician is configuring a small office network with a managed switch. The network has two VLANs: VLAN 10 for workstations (192.168.10.0/24) and VLAN 20 for servers (192.168.20.0/24). The switch ports for workstations are set to access mode and assigned to VLAN 10. The server ports are also set to access mode and assigned to VLAN 20. The router is connected to one of the switch ports and is configured with subinterfaces (192.168.10.1 on VLAN 10 and 192.168.20.1 on VLAN 20) to route between VLANs. A workstation on VLAN 10 cannot ping a server on VLAN 20. The workstation can ping other workstations on VLAN 10. The technician has verified the router subinterfaces are configured correctly. 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.
Distractor review
A
Access mode is the correct configuration for workstation and server ports that belong to a single VLAN. This is not the problem.
Best answer
B
The switch port connecting to the router must be configured as a trunk to carry both VLAN 10 and VLAN 20 traffic. If it is left in default access mode (usually VLAN 1), only that single VLAN traffic will reach the router, breaking inter-VLAN routing.
Distractor review
C
If the server's default gateway were set incorrectly, the server would not be able to respond to the workstation's ping, but the workstation would still send the initial request. However, since the workstation cannot even reach the router for routing, this is not the primary cause.
Distractor review
D
The workstation's subnet mask (255.255.255.0) is correct for its /24 subnet. An incorrect subnet mask would cause issues communicating even within VLAN 10, which is not the case.
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: B — For a router to route traffic between VLANs, the switch port connecting to the router must be configured as a trunk port, allowing multiple VLAN tags (802.1Q) to pass. If that port is set to access mode, it will only carry traffic for a single VLAN, effectively blocking all inter-VLAN communication. The most common misconfiguration is forgetting to set the uplink port to trunk mode.
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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