Question 1mediummulti select
Full question →mediummulti selectObjective-mapped
A switch port is configured with port-security violation mode restrict. Which two statements are true when an unauthorized MAC address appears?
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
Frames from the unauthorized MAC are dropped
Restrict does not allow the violating traffic through.
B
Best answer
The port remains up
Restrict does not err-disable the interface.
C
Distractor review
The interface immediately goes into err-disabled state
That is shutdown mode behavior.
D
Distractor review
The switch converts the port to a trunk automatically
Port security does not do that.
E
Distractor review
The violation mode changes itself to shutdown after three attempts
That is not automatic behavior.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is mistaking the restrict violation mode for shutdown mode. Many candidates incorrectly believe that restrict mode disables the port immediately upon detecting an unauthorized MAC address. However, restrict mode only drops the violating frames and increments the violation counter, allowing the port to remain operational. This confusion often leads to selecting the shutdown-related answer, which is incorrect for restrict mode. Remember, shutdown mode is the one that err-disables the interface, not restrict. Misunderstanding this difference can cause errors in exam questions about port security violation behaviors.
Technical deep dive
How to think about this question
Port security is a fundamental feature in Cisco switches that enhances network security by restricting input to an interface based on MAC addresses. It allows administrators to specify which MAC addresses are allowed on a port, limiting access to authorized devices only. When an unauthorized MAC address attempts to send traffic, the switch reacts based on the configured violation mode, which can be protect, restrict, or shutdown. In restrict mode, the switch drops frames from unauthorized MAC addresses and increments a violation counter, but crucially, it keeps the port operational. This behavior contrasts with shutdown mode, where the port is immediately placed into an err-disabled state, effectively shutting down the interface until manually re-enabled. Restrict mode thus provides a balance between security and availability by blocking unauthorized traffic without disrupting legitimate communication on the port. A common exam trap is confusing restrict mode with shutdown mode. Candidates might incorrectly assume that restrict mode disables the port after violations, but it only drops unauthorized frames and logs violations. This distinction is important in practical networking scenarios where maintaining uptime is critical, and administrators want to monitor violations without causing network outages. Understanding this behavior helps in designing secure yet resilient network environments.
KKey Concepts to Remember
- Port security on Cisco switches controls access by limiting the number of MAC addresses allowed on a switch port to prevent unauthorized devices from connecting.
- The restrict violation mode drops frames from unauthorized MAC addresses and increments the violation counter without disabling the port.
- The shutdown violation mode immediately places the port into an err-disabled state, effectively disabling the interface upon a security violation.
- Port security violation modes do not automatically change based on the number of violations; the configured mode remains until manually changed.
- Port security does not convert access ports to trunk ports automatically under any violation mode.
- When a port is in restrict mode, it continues forwarding legitimate traffic from authorized MAC addresses while blocking unauthorized ones.
- Violation counters in restrict mode help network administrators monitor security breaches without causing network downtime.
- Understanding the difference between restrict and shutdown modes is critical for maintaining network availability and security balance.
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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More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
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Question 2
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Question 3
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Question 4
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Question 5
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FAQ
Questions learners often ask
What does this 200-301 question test?
Port security on Cisco switches controls access by limiting the number of MAC addresses allowed on a switch port to prevent unauthorized devices from connecting.
What is the correct answer to this question?
The correct answer is: Frames from the unauthorized MAC are dropped — Restrict drops frames from violating MAC addresses and can increment the violation counter while keeping the port up. Shutdown would err-disable the port instead.
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.
Discussion
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