350-401 Question 614
Single answerA network administrator has configured an IOS DHCP server on a router to provide IPv4 addresses to clients in VLAN 10. Despite the configuration, the clients are not receiving IP addresses. Upon investigation, you find that the DHCP server is correctly configured, but the clients are located on a different subnet connected to a Layer 3 switch. What is the most likely issue?
- A
The router's DHCP server is not enabled.
- B
The switch is not configured to relay DHCP requests to the router.
- C
The DHCP scope on the router is missing the default gateway option.
- D
The clients have static IP configurations that conflict with the DHCP pool.
Show answer and explanation
Correct answer: B
Explanation
When clients are on a different subnet from the DHCP server, a DHCP relay (configured using the 'ip helper-address' command) is required on the Layer 3 device to forward DHCP requests to the server. Without this configuration, the DHCP server will not receive requests from clients outside its local subnet, causing the clients to fail in obtaining IP addresses.
- A. Incorrect.
If the DHCP server was not enabled on the router, no DHCP service would be provided, but in this case, the server is reported to be correctly configured.
- B. Correct.
If the clients are on a different subnet, the switch must be configured as a DHCP relay to forward DHCP requests to the server. Without this configuration, the DHCP requests will not reach the server.
- C. Incorrect.
While a missing default gateway option could cause routing issues for the clients, it would not prevent them from receiving IP addresses from the DHCP server.
- D. Incorrect.
If the clients had static IP configurations, they would not send DHCP requests. However, this does not explain why DHCP requests are not being processed.