350-601 Security Practice Question
An engineer is troubleshooting a DHCP issue in a data center VLAN. Clients are unable to obtain IP addresses from the DHCP server. The switch has DHCP snooping enabled on the VLAN, and the DHCP server is connected to a trusted port. The clients are on untrusted ports. Which additional security feature is most likely causing the problem if the DHCP server is on a different subnet and the switch is not configured as a DHCP relay?
⚠ Common exam trap
Cisco often tests the misconception that DHCP snooping alone handles cross-subnet DHCP, when in fact it requires an IP helper address or a dedicated DHCP relay agent to forward broadcasts between subnets.
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
✓
DHCP snooping with no IP helper address configured
When the DHCP server resides on a different subnet and the switch lacks an IP helper address (ip helper-address) configuration, DHCP snooping will not forward the DHCP broadcast from the client to the server. DHCP snooping relies on the switch to relay DHCP packets across subnets; without the helper address, the broadcast is dropped at the VLAN interface, preventing clients from obtaining IP addresses.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
DHCP snooping with no IP helper address configured
Why this is correct
DHCP snooping on untrusted ports drops DHCPOFFER from outside the subnet unless relay is set up.
- ✗
Dynamic ARP Inspection (DAI)
Why it's wrong here
DAI validates ARP packets, not DHCP.
- ✗
Control Plane Policing (CoPP) dropping DHCP packets
Why it's wrong here
CoPP might drop if rate-limited, but DHCP is typically not rate-limited aggressively.
- ✗
Port security with maximum MAC limit
Why it's wrong here
Port security limits MACs but does not block DHCP.
Visual reference
Go deeper
Related to this question
About these practice questions
One of 984 original 350-601 practice questions on Courseiva, each with a full explanation and wrong-answer analysis — not exam dumps or protected exam content. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This 350-601 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 350-601 exam.