Which of the following characteristics describe the BPDU Guard feature? (Choose all that apply.)
A.
A BPDU Guard port should only be configured on ports with PortFast enabled.
B.
BPDU Guard and PortFast should not be enabled on the same port.
C.
BPDU Guard is used to ensure that superior BPDUs are not received on a switch port.
D.
A BPDU Guard port receiving a BPDU will go into err-disable state.
E.
A BPDU Guard port receiving a BPDU will be disabled.
F.
BPDU Guard can be enabled on any switch port.
Explanation:
PortFast should be configured on port where bridging loops are not expected to form (which means
that no BPDUs should be receive on these ports), such as on end-devices port like a single
workstation or server. PortFast provides quick network access by entering directly in STP forwarding
state (bypassing listning and learning state). Even if PortFast can detect a bridging loop (While
PortFast is enabled on a port, STP is still running), it will detect it in a finite amount of time that is to
say the length of time required to move the port through the normal STP states.
If any BPDUs (superior to the current root or not) are received on port configured with BPDU Guard
that port is put immediately in errdisable state.
If configured in global configuration mode BPDU Guard will be enable on all configured PortFast ports:If configured in interface configuration mode it will only be enable on the specific port:
BPDU guard should be configured on all switchs ports where STP PortFast is enabled. This prevents
any possibility that a switch will be added to the port either intentionally or by mistake.
