CCNP Infrastructure Practice Question
A network engineer is configuring a Cisco IOS router to act as a DHCP server for a subnet that also contains a DHCP relay agent. The router must ensure that DHCP clients receive the correct default gateway address of 10.1.1.1, which is the router's own interface on that subnet. Which command is required to accomplish this?
⚠ Common exam trap
Watch out — candidates often confuse the ip helper-address command, which is used for DHCP relay, with the default-router command, which sets the gateway for DHCP clients.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
ip dhcp pool POOL1 followed by default-router 10.1.1.1
To provide DHCP clients with a default gateway, the network engineer must configure the default-router command within the DHCP pool. This command specifies the IP address of the gateway that clients will use to reach other networks. The other options are either for different purposes or do not configure the DHCP server to supply gateway information.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
ip dhcp excluded-address 10.1.1.1
Why it's wrong here
The ip dhcp excluded-address command prevents the router from assigning specific addresses to clients. While it might be used to exclude the router's own address from the pool, it does not provide the default gateway information to clients. It is not the correct command for setting the gateway.
- ✓
ip dhcp pool POOL1 followed by default-router 10.1.1.1
Why this is correct
The default-router command inside the DHCP pool configuration specifies the default gateway address that clients receive. Since the router's interface on the subnet is 10.1.1.1, this command ensures clients are configured with that address as their gateway, which is essential for proper routing.
- ✗
ip default-gateway 10.1.1.1 in global configuration mode
Why it's wrong here
The ip default-gateway command is used on a device that does not have routing enabled, such as a Layer 2 switch, to set its own default gateway. It does not affect DHCP clients. This command is for the device itself, not for the DHCP pool configuration.
- ✗
ip helper-address 10.1.1.1 under the router's interface
Why it's wrong here
The ip helper-address command is used on a DHCP relay agent to forward broadcast DHCP requests to a DHCP server. It does not configure the default gateway that clients receive in their DHCP lease. This command is irrelevant to the DHCP server configuration task.
Visual reference
About these practice questions
This 350-401 question is part of Courseiva's 1,923-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Cisco exam blueprint
This 350-401 practice question is part of Courseiva's free Cisco certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the 350-401 exam.