CompTIA A+ Core 1 (220-1201)Hardware and Network TroubleshootingHard
A technician troubleshoots a workstation that cannot access any network resources or the internet. Running ipconfig reveals an IP address of 169.254.34.12. The network cable is confirmed to be connected and the switch port shows link activity. What is the MOST likely cause of this issue?
- AThe DNS server address is incorrect
- BThe workstation failed to receive a DHCP-assigned address
- CThe default gateway is unreachable
- DA duplicate IP address exists on the network
Show answer & explanationAnswer & explanation
Correct answer: B. The workstation failed to receive a DHCP-assigned address
An address in the 169.254.0.0/16 range is an Automatic Private IP Addressing (APIPA) address, assigned by Windows when a DHCP server cannot be reached. This confirms the DHCP request failed despite a valid physical link.
Why the other options are wrong
- A. DNS issues would still allow a valid DHCP-assigned IP; the address itself would not be 169.254.x.x.
- C. A gateway issue would occur with a valid IP address, not an APIPA address.
- D. A duplicate IP typically triggers a Windows conflict warning, not an APIPA assignment.
APIPA (Automatic Private IP Addressing)
When a Windows client cannot obtain an IP address from a DHCP server, it self-assigns an address in the 169.254.0.0/16 range so it can still communicate on the local segment.
- Range: 169.254.0.1 to 169.254.255.254
- Indicates DHCP server unreachable or unavailable
- Device can only communicate with other APIPA devices on the same local segment
Memory trick: '169 means DHCP said no.'