What two things will occur when an edge port receives a BPDU? (Choose two.)
A.
The port immediately transitions to the Forwarding state.
B.
The switch generates a Topology Change Notification (TCN) BPDU.
C.
The port immediately transitions to the err-disable state.
D.
The port becomes a normal STP switch port.
I think it is C and D.
One other benefit of PortFast is that
Topology Change Notification (TCN) BPDUs are not sent when a switch port in PortFast
mode goes up or down. This simplifies the TCN transmission on a large network when
end-user workstations are coming up or shutting down.
C is not correct unless you configured BPDU Guard.
Correct. But neither is B as far as I`ve seen on Cisco`s site and documentation.
B is correct. (D as well)
Port Edge means RSTP. Topology change packet are sent by non root bridge when a “non-edge” port transition to the forwarding state . This is the case when you port which previously was an edge port, receive a bpdu. the port becomes a non-edge port and remains and goes through the phases learning / forwarding. This triggers the TCN