Quick Answer
The correct answers are Port Security and DHCP Snooping, as these two features work together to prevent MAC flooding attacks on a Cisco Nexus switch. Port Security directly mitigates flooding by limiting the number of MAC addresses permitted on a single port, causing the switch to drop frames from unknown source MACs once the configured limit is exceeded, which stops the switch’s CAM table from being overwhelmed. DHCP Snooping complements this by building a trusted database of IP-to-MAC bindings from legitimate DHCP messages, enabling the switch to validate traffic and block spoofed MAC addresses that often accompany flooding attempts. On the Cisco DCCOR / CCNP Data Center Core 350-601 exam, this topic tests your understanding of Layer 2 security mechanisms specific to Nexus switches; a common trap is confusing Dynamic ARP Inspection (which relies on DHCP Snooping’s binding table) with a direct flooding prevention tool. Remember the memory tip: “Port limits the MACs, Snooping checks the facts”—Port Security caps the count, while DHCP Snooping validates the bindings.
This 350-601 practice question tests your understanding of security. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
Which TWO security features are used to prevent MAC address flooding attacks on a Cisco Nexus switch? (Choose two.)
Port Security
Port Security limits the number of MAC addresses per port.
IP Source Guard
Why wrong: IPSG prevents IP spoofing, not MAC flooding.
Control Plane Policing
Why wrong: CoPP protects control plane, not MAC flooding.
DHCP Snooping
DHCP Snooping can rate-limit DHCP requests and prevent MAC flooding via the binding table.
BPDU Guard
Why wrong: BPDU Guard protects against spanning-tree attacks.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Port Security
Port Security (A) is correct because it limits the number of MAC addresses allowed on a switch port, preventing MAC flooding attacks by dropping frames from unknown source MACs once the limit is exceeded. DHCP Snooping (D) is correct because it builds a trusted database of IP-to-MAC bindings from DHCP messages, which can be used to validate traffic and prevent MAC spoofing that often accompanies flooding attacks.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
Port Security
Why this is correct
Port Security limits the number of MAC addresses per port.
Related concept
Read the scenario before looking for a memorised answer.
IP Source Guard
Why it's wrong here
IPSG prevents IP spoofing, not MAC flooding.
Control Plane Policing
Why it's wrong here
CoPP protects control plane, not MAC flooding.
DHCP Snooping
Why this is correct
DHCP Snooping can rate-limit DHCP requests and prevent MAC flooding via the binding table.
Related concept
Read the scenario before looking for a memorised answer.
BPDU Guard
Why it's wrong here
BPDU Guard protects against spanning-tree attacks.
Common exam traps
Cisco often tests the distinction between features that directly prevent MAC flooding (Port Security, DHCP Snooping) versus features that mitigate related spoofing attacks (IP Source Guard, Dynamic ARP Inspection), leading candidates to mistakenly select IP Source Guard.
Detailed technical explanation
MAC flooding attacks exploit the limited size of the CAM table (typically 8K–128K entries) by sending frames with random source MAC addresses, causing the switch to flood unicast traffic out all ports. Port Security enforces a per-port MAC limit (e.g., switchport port-security maximum 1) and can shut down or restrict the port when exceeded. DHCP Snooping builds a binding table (ip dhcp snooping binding) that is also used by Dynamic ARP Inspection and IP Source Guard, but its primary role in MAC flooding prevention is to validate source MAC addresses against DHCP leases, making it harder for an attacker to spoof legitimate MACs.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
A practitioner preparing for the 350-601 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
What to study next
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Security — study guide chapter
Learn the concepts, then practise the questions
Security practice questions
Targeted practice on this topic area only
All 350-601 questions
500 questions across all exam domains
Cisco DCCOR / CCNP Data Center Core 350-601 study guide
Full concept coverage aligned to exam objectives
350-601 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise 350-601 questions linked to Network.
Practise 350-601 questions linked to Compute.
Practise 350-601 questions linked to Storage Network.
Practise 350-601 questions linked to Automation.
Practise 350-601 questions linked to Security.
Practise 350-601 questions linked to 350-601 fundamentals.
Practise 350-601 questions linked to 350-601 scenario.
Practise 350-601 questions linked to 350-601 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Security — This question tests Security — Read the scenario before looking for a memorised answer..
The correct answer is: Port Security — Port Security (A) is correct because it limits the number of MAC addresses allowed on a switch port, preventing MAC flooding attacks by dropping frames from unknown source MACs once the limit is exceeded. DHCP Snooping (D) is correct because it builds a trusted database of IP-to-MAC bindings from DHCP messages, which can be used to validate traffic and prevent MAC spoofing that often accompanies flooding attacks.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 24, 2026
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.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.