Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
Which port-security violation mode drops frames from unauthorized MAC addresses but keeps the interface up and does not send an SNMP trap or syslog message?
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
protect
Correct. Protect is the quietest enforcement mode.
B
Distractor review
restrict
Restrict provides similar forwarding behavior but tracks and reports violations.
C
Distractor review
shutdown
Shutdown places the port into err-disabled state after a violation.
D
Distractor review
shutdown vlan
Shutdown vlan is not the standard switchport port-security violation mode being tested here.
Common exam trap
Common exam trap: answer the scenario, not the keyword
A frequent exam trap is mistaking the protect mode for restrict mode because both drop unauthorized frames. Candidates often assume that any violation mode dropping frames must generate alerts or disable the port. However, protect mode silently drops frames without sending syslog messages or SNMP traps and keeps the interface operational. Confusing these modes leads to selecting restrict or shutdown instead of protect. Remember, protect is the quietest violation mode, designed to enforce security without disrupting network availability or alerting administrators automatically.
Technical deep dive
How to think about this question
Port-security is a Layer 2 security feature on Cisco switches that restricts input to an interface by limiting and identifying MAC addresses of the stations allowed to access the port. When a frame with an unauthorized MAC address is received, the switch triggers a violation event. The violation mode configured on the port determines the switch's response to this event, which can range from silently dropping frames to disabling the port entirely. The protect violation mode is the least intrusive enforcement method. It drops frames from unauthorized MAC addresses without generating any log messages or SNMP traps, and crucially, it keeps the interface in an up state. This mode is useful when administrators want to enforce security quietly without alerting network management systems or disrupting legitimate traffic. In contrast, the restrict mode also drops unauthorized frames but increments violation counters and sends notifications, while the shutdown mode disables the port by placing it into an err-disabled state, requiring manual intervention to restore connectivity. A common exam trap is confusing protect with restrict mode because both drop unauthorized frames. However, protect is silent and non-disruptive, whereas restrict provides alerts and counters. Misunderstanding this distinction can lead to incorrect answers. Practically, protect mode is ideal in environments where maintaining port availability is critical and administrators prefer to monitor violations manually rather than receive automated alerts. This behavior aligns with Cisco’s design to offer flexible security enforcement tailored to network policies.
KKey Concepts to Remember
- Port-security violation modes determine how a switch port reacts when frames from unauthorized MAC addresses are detected.
- The protect mode drops unauthorized frames silently without generating syslog messages or SNMP traps, keeping the interface operational.
- The restrict mode also drops unauthorized frames but increments violation counters and sends syslog messages and SNMP traps for monitoring.
- The shutdown mode places the port into an err-disabled state after a violation, effectively disabling the interface until manually re-enabled.
- Port-security protects Layer 2 networks by limiting access based on MAC addresses, preventing unauthorized devices from communicating.
- Cisco switches use violation modes to balance security enforcement with network availability and administrative alerting.
- Choosing the correct violation mode depends on the desired trade-off between security visibility and network uptime.
- Understanding port-security violation modes is essential for configuring secure access on switchports in Cisco networks.
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 violation modes determine how a switch port reacts when frames from unauthorized MAC addresses are detected.
What is the correct answer to this question?
The correct answer is: protect — Protect silently drops frames from unauthorized sources while leaving the interface up. Restrict also drops frames but increments the violation counter and can generate notifications.
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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