Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A network administrator recently installed a new firewall to replace an older router. After the installation, users can access the internet but cannot reach internal web servers by hostname (e.g., http://intranet). They can, however, access those servers by IP address. The administrator verifies that the DNS server is functioning and other traffic between the LAN and the internal server VLAN is allowed. What 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
Best answer
The firewall is blocking DNS traffic (UDP/TCP port 53) between the LAN and the internal DNS server
Correct. If DNS queries cannot reach the internal DNS server, users cannot resolve internal hostnames even though external resolution works (if forwarded to public DNS).
B
Distractor review
The VLAN configuration on the switch is preventing hostname resolution
VLANs operate at Layer 2 and do not affect DNS resolution. The routing between VLANs is handled by the firewall/router; the switch alone cannot block DNS.
C
Distractor review
The DHCP server is not assigning the correct DNS server address
If users were getting a wrong DNS server, external resolution would also likely fail. Users can access the internet, so DNS for public names works.
D
Distractor review
The default gateway address has been misconfigured on the firewall
Internet access works, so the default gateway is correctly configured. Internal hostname resolution does not depend on the default gateway.
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 firewall is blocking DNS traffic (UDP/TCP port 53) between the LAN and the internal DNS server — The fact that users can access internal servers by IP but not by name indicates name resolution is failing for internal names. The DNS server is functional, so the problem is likely that the firewall is blocking DNS queries between the LAN and the internal DNS server. Although other traffic is allowed, DNS traffic on UDP/TCP port 53 may have been inadvertently blocked by a default deny rule or a misconfigured access control list (ACL). Layer 3 switch or router settings are not directly involved, and the default gateway is working since internet access is fine.
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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