A workstation located in a university research laboratory displays a limited connectivity icon after being moved to a new wall jack. Running `ipconfig /all` reveals an IPv4 address of 169.254.108.72 with a subnet mask of 255.255.0.0 and no default gateway configured. The user can successfully ping nearby laboratory computers that also show 169.254.x.x addresses, but cannot access internal servers or external websites. Which of the following represents the MOST likely root cause of this connectivity issue?
- The workstation cannot establish communication with a DHCP server to obtain a valid IP configuration.Answer
- BThe DNS server is offline and unable to assign IP addresses to local network hosts.
- CThe Ethernet cable is damaged or physically disconnected from the network interface card.
- DAn unmanaged Layer 2 switch is incorrectly configured to block IP routing between local subnets.
Answer
The workstation cannot establish communication with a DHCP server to obtain a valid IP configuration.
The correct option correctly identifies DHCP server unreachability as the cause of APIPA address assignment (169.254.x.x). When a client operating system cannot reach a DHCP server to request network configuration parameters, APIPA automatically generates a link-local address, allowing limited local communication but preventing default gateway assignment and internet routing.
Step-by-Step Solution
Key Concept
Automatic Private IP Addressing (APIPA) and DHCP Failure Diagnosis