Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A network technician is troubleshooting inter-VLAN routing. Clients on VLAN 10 (192.168.10.0/24) cannot communicate with servers on VLAN 20 (192.168.20.0/24). The router has subinterfaces configured for both VLANs and an ACL that permits all traffic between them. The router connects to a Layer 2 switch via a single cable. The switch port connecting to the router is configured as an access port in VLAN 10. Which of the following is the MOST likely cause of the communication failure?
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
The switch port connecting to the router is configured as an access port instead of a trunk
Correct. The switch port must be a trunk to pass traffic for multiple VLANs. An access port only allows a single VLAN, so VLAN 20 frames are dropped by the switch.
B
Distractor review
The ACL is blocking traffic between VLAN 10 and VLAN 20
The problem statement says the ACL permits all traffic between the VLANs, so this is not the cause.
C
Distractor review
The router's subinterface for VLAN 20 has an incorrect IP address
If the subinterface IP were wrong, clients on VLAN 10 might not be able to reach the gateway, but the issue here is that frames from VLAN 20 never reach the router due to the access port configuration.
D
Distractor review
The switch is not configured with VLAN 20
If the switch had no VLAN 20, then servers on VLAN 20 could not communicate at all. The problem is specifically about routing between VLANs, not about local connectivity.
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 instead of a trunk — For a router to route between VLANs using subinterfaces, the switch port connecting to the router must be configured as a trunk port. A trunk port carries traffic for multiple VLANs (tagged), allowing the router to receive frames from both VLAN 10 and VLAN 20. An access port only carries traffic for a single VLAN (untagged). Since the switch port is set as an access port for VLAN 10, frames from VLAN 20 never reach the router, so clients on VLAN 10 cannot communicate with servers on VLAN 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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