CCNA: Cisco Certified Network Associate — Question 1266

Which command on a port enters the forwarding state immediately when a PC is connected to it?

Answer options

• A. switch(config)#spanning-tree portfast default
• B. switch(config)#spanning-tree portfast bpduguard default
• C. switch(config-if)#spanning-tree portfast trunk
• D. switch(config-if)#no spanning-tree portfast

Correct answer: A

Explanation

The command 'switch(config)#spanning-tree portfast default' enables PortFast globally, allowing ports to skip the listening and learning states and immediately enter the forwarding state when a device connects. The other options either enable BPDU guard, configure a trunk port, or disable PortFast, which do not achieve the immediate forwarding state when a PC is connected.