What CLI command is used to enable PortFast on a switch port?

What CLI command is used to enable PortFast on a switch port?

• A. Switchport mode access
• B. Spanning-tree portfast
• C. Duplex full
• D. VTP mode client

Answer: (B)

The command used to enable PortFast on a switch port is "spanning-tree portfast." PortFast is a feature that allows a switch port to transition directly to the forwarding state from the blocking state, bypassing the usual listening and learning states of the Spanning Tree Protocol (STP). This is particularly useful for ports that are directly connected to end devices, such as workstations or servers, as it minimizes the downtime that would otherwise occur when the Spanning Tree process is engaged. When PortFast is enabled on a port, it helps in reducing the time it takes for the end device to begin communicating after it is powered on or connected. This is crucial for environments that require quick connections, such as VoIP phones and devices that rely on rapid network access. The command "switchport mode access" is utilized to set the port as an access port for VLAN assignments but does not pertain to the STP features. "Duplex full" is related to configuring the duplex settings of the port, while "VTP mode client" deals with VLAN Trunking Protocol settings and does not influence STP directly. Hence, enabling PortFast specifically requires the correct application of the "spanning-tree portfast" command on the intended interface.

The command used to enable PortFast on a switch port is "spanning-tree portfast." PortFast is a feature that allows a switch port to transition directly to the forwarding state from the blocking state, bypassing the usual listening and learning states of the Spanning Tree Protocol (STP). This is particularly useful for ports that are directly connected to end devices, such as workstations or servers, as it minimizes the downtime that would otherwise occur when the Spanning Tree process is engaged.

When PortFast is enabled on a port, it helps in reducing the time it takes for the end device to begin communicating after it is powered on or connected. This is crucial for environments that require quick connections, such as VoIP phones and devices that rely on rapid network access.

The command "switchport mode access" is utilized to set the port as an access port for VLAN assignments but does not pertain to the STP features. "Duplex full" is related to configuring the duplex settings of the port, while "VTP mode client" deals with VLAN Trunking Protocol settings and does not influence STP directly. Hence, enabling PortFast specifically requires the correct application of the "spanning-tree portfast" command on the intended interface.