On what switch ports should BPDU guard be enabled to enhance STP stability?
- only ports that are elected as designated ports
- only ports that attach to a neighboring switch
- all PortFast-enabled ports
- all trunk ports that are not root ports
| Explanation & Hint:
BPDU guard should be enabled on all PortFast-enabled ports. PortFast is typically used on switch ports connected to end devices, where Spanning Tree Protocol (STP) participation isn’t necessary because the port is not expected to create a loop in the network topology. Enabling BPDU guard on these ports ensures that the switch will put the port into an error-disabled state if a BPDU is received, thus preventing potential loops by blocking the possibility of switch-to-switch links forming where they are not expected. This enhances the stability of STP by ensuring that the network topology remains loop-free. |