200-901 Question 175
Single answerA network engineer is troubleshooting a connectivity issue between two devices on the same subnet. The devices can ping their default gateway but cannot ping each other. Which of the following could be the most likely cause of the issue?
- A
A misconfigured subnet mask on one or both devices
- B
A Layer 2 switch port operating in the wrong VLAN
- C
A routing issue in the network
- D
A firewall rule blocking traffic between the devices
Show answer and explanation
Correct answer: B
Explanation
Since the devices are on the same subnet and can ping their default gateway, there is no issue with their subnet mask or routing. The most likely cause is an issue at Layer 2, such as one of the devices being assigned to the wrong VLAN. This would prevent them from communicating with each other even though they can reach the gateway.
- A. Incorrect.
A misconfigured subnet mask could cause devices to fail to communicate if they are not recognized as being on the same subnet. However, if both devices can ping their default gateway, their subnet masks are likely correct.
- B. Correct.
A Layer 2 switch port operating in the wrong VLAN would prevent the devices from communicating, even if they are on the same subnet. This is the most likely cause of the issue in this scenario.
- C. Incorrect.
A routing issue would not be relevant in this scenario because the devices are on the same subnet and do not require routing to communicate.
- D. Incorrect.
A firewall rule blocking traffic between the devices is unlikely in this scenario because firewalls typically operate at Layer 3 or higher, and the devices are on the same subnet.