A technician is troubleshooting a workstation that cannot access any network resources. The technician runs ipconfig and sees that the IP address is 169.254.10.50 with subnet mask 255.255.0.0. The link lights on the NIC and the switch port are solid green. The technician connects the workstation to a different wall jack using a known-good cable, but the problem persists. 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.
Distractor review
The switch port is administratively disabled
An administratively disabled switch port typically has no link light (or a different indicator). Since the link light is solid green, the port is enabled and passing traffic at Layer 1.
Best answer
The DHCP server is unavailable
APIPA is automatically assigned Windows when no DHCP response is received. The physical connectivity is good (link lights, cable test), so the failure lies in the DHCP process itself, likely because the DHCP server is down, unreachable, or misconfigured.
Distractor review
The default gateway is misconfigured on the router
A misconfigured default gateway would still allow the workstation to obtain a valid IP address via DHCP. The presence of an APIPA address indicates the DHCP transaction failed before the gateway configuration even matters.
Distractor review
The DNS server is not responding
A non-responsive DNS server would not prevent the workstation from obtaining an IP address from DHCP. The workstation would still get a valid IP, and only name resolution would fail.
Common exam trap
Common exam trap: usable hosts are not the same as total addresses
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Technical deep dive
How to think about this question
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
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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?
CIDR notation defines the prefix length.
What is the correct answer to this question?
The correct answer is: The DHCP server is unavailable — An IP address in the 169.254.x.x range (APIPA) indicates that the workstation failed to obtain a valid IP address from a DHCP server. Solid link lights confirm Layer 1 connectivity, and testing with a different wall jack and known-good cable isolates the issue away from the physical medium. Therefore, the DHCP server is most likely unavailable or not responding.
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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