Learn about the default action taken by a switch when the MAC address limit is reached on a port. Discover how traffic is handled for the offending MAC address. Prepare for the Juniper JN0-351 certification exam with this detailed explanation.
Table of Contents
Question
Which statement about the default action of MAC limiting is true when the number of MAC addresses has hit the limit set?
A. The switch will shut down MAC learning on the offending port for five minutes.
B. The switch stops learning MAC addresses on the offending port, but floods traffic out of all ports for the offending MAC address.
C. The switch stops learning MAC addresses on the offending port, and any traffic to or from the offending MAC address will be dropped.
D. The switch will shut down the offending port for five minutes.
Answer
C. The switch stops learning MAC addresses on the offending port, and any traffic to or from the offending MAC address will be dropped.
Explanation
When a switch reaches the configured MAC address limit on a port, the default action is to stop learning new MAC addresses on that specific port. This means that the switch will no longer add new entries to its MAC address table for the offending port.
Furthermore, any traffic originating from or destined to the MAC address that caused the limit to be exceeded will be dropped by the switch. This is done to prevent the switch from being overwhelmed with an excessive number of MAC addresses, which could potentially lead to a MAC address table overflow and impact the switch’s performance.
It’s important to note that the switch does not flood traffic out of all ports for the offending MAC address, nor does it shut down the offending port for a specific duration. The switch simply stops learning new MAC addresses on the affected port and drops traffic associated with the offending MAC address until the issue is resolved, typically by manually clearing the MAC address table or waiting for the dynamic entries to expire.
Therefore, the correct answer to the question is option C: The switch stops learning MAC addresses on the offending port, and any traffic to or from the offending MAC address will be dropped.
Understanding the default behavior of MAC limiting is crucial for managing and troubleshooting Layer 2 network issues. By configuring appropriate MAC address limits on switch ports, network administrators can prevent MAC address table exhaustion and ensure the stability and security of the network.
Juniper JN0-351 certification exam assessment practice question and answer (Q&A) dump including multiple choice questions (MCQ) and objective type questions, with detail explanation and reference available free, helpful to pass the Juniper JN0-351 exam and earn Juniper JN0-351 certification.