Troubleshooting Cisco SW1 Interface g0/1: Reasons for Interface Condition

Valid Reasons for SW1 Interface g0/1 in Down/Down State

Question

The SW1 interface g0/1 is in the down/down state.

Which two configurations are valid reasons for the interface condition? (Choose two.)

Answers

Explanations

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A. B. C. D. E.

CD.

The "down/down" interface status means that the physical link is not operational and the interface is also not able to detect any Layer 2 (data-link layer) connectivity. There are various reasons that can cause an interface to go into the down/down state, including:

A. Protocol Mismatch: This occurs when the two connected devices are configured with different Layer 1 (physical layer) protocols, such as Ethernet and Token Ring. In this scenario, the interface will not be able to detect the physical link, and it will go into the down/down state.

B. Duplex Mismatch: This occurs when the connected devices are configured with different duplex settings, such as half-duplex and full-duplex. In this case, the interface will be able to detect the physical link but won't be able to establish Layer 2 connectivity, causing it to go into the down/down state.

C. Shutdown Interface: An interface can also be in the down/down state if it has been administratively shut down. This is usually done using the "shutdown" command on the interface.

D. Error-Disabled Interface: This is a state where the interface has been automatically disabled by the device due to a specific error condition, such as a port-security violation or a spanning-tree loop. In this case, the interface will be in the error-disabled state, but it will also show as down/down.

E. Speed Mismatch: This occurs when the connected devices are configured with different speed settings, such as 10 Mbps and 100 Mbps. In this scenario, the interface will be able to detect the physical link but won't be able to establish Layer 2 connectivity, causing it to go into the down/down state.

Therefore, the two valid configurations that could cause an interface to be in the down/down state are: A. There is a protocol mismatch B. There is a duplex mismatch