200-301 Question 190
Single answerA network engineer is configuring a new switch in an enterprise network. The engineer needs to connect the switch to an existing trunk link between two other switches to allow multiple VLANs to traverse. Which configuration step is essential for the interface on the new switch to function as a trunk port?
- A
Set the switchport mode to trunk on the interface.
- B
Assign the interface to VLAN 1.
- C
Enable PortFast on the interface.
- D
Configure a native VLAN for the trunk interface.
Show answer and explanation
Correct answer: A
Explanation
To configure an interface as a trunk port, the 'switchport mode trunk' command must be issued. This command enables the interface to carry traffic for multiple VLANs. Assigning the interface to VLAN 1 or enabling PortFast does not configure it as a trunk, and configuring a native VLAN is an additional step that is not essential for enabling trunking.
- A. Correct.
Correct. Setting the switchport mode to trunk is required to configure the interface as a trunk port, allowing multiple VLANs to traverse the link.
- B. Incorrect.
Incorrect. Assigning an interface to VLAN 1 makes it an access port for VLAN 1, which is different from configuring a trunk port.
- C. Incorrect.
Incorrect. PortFast is used on access ports to avoid Spanning Tree Protocol delays, but it is not suitable for trunk ports.
- D. Incorrect.
Incorrect. Configuring a native VLAN is optional and is used to handle untagged traffic on a trunk, but it does not convert the interface into a trunk port.