Enabling and Disabling Backbonefast feature on a switch

Description: This lab exercise demonstrates the usage of the backbonefast command on the switch.

Instructions

1. Enter into the global configuration mode on the switch. 
2. Use the command "Spanning-tree backbonefast" to enable backbonefast feature on the switch and verify the same using show command. 
3. Use the no form of the above command to disable the backbonefast on switch and verify the same using show spanning-tree summary command.