Question 1easymultiple choice
Full question →easymultiple choiceObjective-mapped
A switchport should allow only one learned MAC address and shut down if a different device is connected later. Which port security violation mode and limit combination best fits that goal?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Best answer
maximum 1 with violation shutdown
This is the strict option that disables the port after a violation.
B
Distractor review
maximum 10 with violation protect
That is far too loose for the requirement.
C
Distractor review
maximum 1 with violation restrict and no logging
Restrict does not shut the port down.
D
Distractor review
maximum unlimited with violation shutdown
Unlimited defeats the purpose of the limit.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is selecting violation modes like 'protect' or 'restrict' when the question demands strict enforcement by shutting down the port. Both 'protect' and 'restrict' allow the port to remain active despite violations, which does not meet the requirement to disable the port upon detecting a different device. Another common mistake is setting the maximum MAC address limit higher than one or unlimited, which contradicts the goal of allowing only a single device. Candidates must carefully distinguish between violation modes and understand their operational impact on port security enforcement.
Technical deep dive
How to think about this question
Port security is a fundamental Layer 2 security feature on Cisco switches designed to restrict the number of MAC addresses learned on a switchport. It helps prevent unauthorized devices from connecting to the network by limiting the MAC addresses that the switch will accept on a given port. When the number of learned MAC addresses exceeds the configured limit, the switch triggers a security violation and takes a predefined action based on the violation mode configured. The violation mode 'shutdown' is the most stringent option available. When a violation occurs, the switchport immediately transitions to the error-disabled state, effectively shutting down the port and blocking all traffic. This mode is ideal when strict control is required, such as allowing only one device per port. Setting the maximum MAC address limit to 1 enforces this policy by permitting only a single device to connect. If a different device attempts to connect, the port shuts down, preventing unauthorized access. A common exam trap is confusing violation modes. Modes like 'protect' and 'restrict' do not disable the port; they only drop unauthorized frames or generate logs, which may allow unauthorized devices to connect without shutting down the port. Another pitfall is setting the maximum MAC address limit too high or unlimited, which defeats the purpose of port security. Practically, using 'maximum 1 with violation shutdown' ensures immediate response to unauthorized devices, maintaining network integrity and simplifying troubleshooting in secure environments.
KKey Concepts to Remember
- Port security on Cisco switches limits the number of MAC addresses learned on a switchport to enhance network access control and prevent unauthorized devices.
- The violation mode 'shutdown' disables the switchport immediately when a security violation occurs, effectively blocking all traffic on that port.
- Setting the maximum MAC address limit to 1 ensures that only a single device can connect to the switchport, preventing multiple devices from sharing the same port.
- Violation mode 'protect' drops packets from unauthorized MAC addresses but does not disable the port, allowing continued traffic from authorized devices.
- Violation mode 'restrict' drops unauthorized packets and generates a log message or SNMP trap but keeps the port active, which does not meet strict security requirements.
- Unlimited MAC address limits defeat the purpose of port security by allowing any number of devices to connect without triggering violations.
- Port security is a Layer 2 feature that helps prevent MAC flooding attacks and unauthorized device access by enforcing MAC address limits per port.
- The combination of maximum 1 MAC address with violation shutdown is the strictest enforcement method to secure access ports in Cisco LAN environments.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
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FAQ
Questions learners often ask
What does this 200-301 question test?
Port security on Cisco switches limits the number of MAC addresses learned on a switchport to enhance network access control and prevent unauthorized devices.
What is the correct answer to this question?
The correct answer is: maximum 1 with violation shutdown — The usual setup is maximum 1 MAC address with violation mode shutdown. That way the port is disabled when an unauthorized device appears.
What should I do if I get this 200-301 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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