I use itprotv, cisco reading, & boson labs. While working in boson labs they ask you some questions regarding output of the show spanning-tree vlan id detail command.
They ask which port is root...
the answer is: Root port is 12 (FastEthernet 0/11), cost of root path is 19.
The question isn't multiple choice and i was able to determine that f0/11 was root by running the wrong show command of sh spanning-tree and seen that f0/11 was forwarding while all other ports are blocked.
What i really want to understand is why would cisco port 12 be f0/11 and not port 11 in a output of this show stp detail command? I'm affraid Cisco is going to offer me this type of question and I am going to choose the incorrect answer because I thinking about the incorrect port when I am really looking at the proper port.
Here is the exact results if I had ran the correct show command. In my mind i see f0/11 as a port.
Port 12 (FastEthernet0/11) of VLAN0001 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.12.
Designated root has priority 0, address 000C.1461.3123
Designated bridge has priority 0, address 000C.1461.3123
Designated port id is 128.12., designated path cost 19
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 0, received 363