Question

Difficulty: MediumIP Addressing and Network Configuration

A field technician connects a desktop computer to a newly activated network drop in an office annex. The organization uses a centralized DHCP server located on the core network segment, while the annex operates on a newly created VLAN. When executing `ipconfig /all`, the workstation reports an IP address of 169.254.88.12169.254.88.12 with a subnet mask of 255.255.0.0255.255.0.0. Physical cabling and link indicators are confirmed operational. Which of the following best explains why the workstation has this specific IP address configuration?

  1. The client computer was unable to contact a DHCP server to acquire a dynamic lease, causing the operating system to self-assign an Automatic Private IP Addressing (APIPA) address.Answer
  2. B
    The local DNS server failed to resolve the computer's hostname, causing the server to assign a fallback diagnostic IP address.
  3. C
    The centralized DHCP server successfully leased a designated private scope reserved specifically for high-priority network drops.
  4. D
    The Layer 2 network switch needs its internal routing table updated to translate the link-local address into a routable IPv4 address.

Answer

The client computer was unable to contact a DHCP server to acquire a dynamic lease, causing the operating system to self-assign an Automatic Private IP Addressing (APIPA) address.
When a client configured for dynamic IP assignment fails to contact a DHCP server, Windows automatically assigns an APIPA address from the 169.254.0.0/16169.254.0.0/16 range. In this scenario, placing the host on a new VLAN without a configured DHCP relay agent prevents DHCP requests from reaching the central DHCP server.

Step-by-Step Solution

1
Analyze the IP address output provided by the command.
The address 169.254.88.12169.254.88.12 falls within the APIPA block (169.254.0.0/16169.254.0.0/16).
Recognizing the APIPA address block identifies that automatic self-configuration took place.
2
Determine why APIPA self-configuration occurs.
APIPA triggers when a host configured for DHCP sends a discovery request but receives no reply before timing out.
Cross-VLAN setups require a DHCP relay agent (IP helper) on the router to forward DHCP requests to a central DHCP server.

Key Concept

APIPA (Automatic Private IP Addressing) identification and DHCP failure causes
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