200-301 Question 80
Single answerA network administrator is troubleshooting a connection issue between two switches. The administrator observes slow network performance and numerous collision and CRC errors on one of the switch ports. Upon further investigation, they find that one switch port is configured for full-duplex, while the other is set to half-duplex. What is the most likely cause of this issue?
- A
A duplex mismatch between the two switch ports
- B
A faulty Ethernet cable between the switches
- C
The switch ports are configured with different VLANs
- D
The cable length exceeds Ethernet standards
Show answer and explanation
Correct answer: A
Explanation
The issue described in the scenario is a classic example of a duplex mismatch. When one device operates in full-duplex mode and the other in half-duplex, the half-duplex device will treat incoming traffic as collisions, leading to CRC errors and significant performance degradation. Ensuring both sides of the connection are configured with the same duplex settings resolves this issue.
- A. Correct.
A duplex mismatch occurs when one side of the link operates in full-duplex and the other in half-duplex, causing issues such as collisions, CRC errors, and degraded performance. This is the most likely cause in this scenario.
- B. Incorrect.
A faulty Ethernet cable could cause connectivity issues, but it is less likely to specifically result in the observed duplex-related symptoms such as collisions and CRC errors.
- C. Incorrect.
Mismatched VLANs would prevent communication entirely, but they would not result in collisions or CRC errors.
- D. Incorrect.
Exceeding Ethernet cable length standards can lead to signal degradation, but it would not specifically cause duplex-related issues like collisions and CRC errors.