Huawei Quidway S8500 Series - Stp Bridge-Diameter

Command Manual – STP
Quidway S8500 Series Routing Switches Chapter 1
MSTP Configuration Commands
Huawei Technologies Proprietary
1-13
View
System view
Parameter
None
Description
Use the stp bpdu-protection command to enable the BPDU protection on the switch.
Use the undo stp bpdu-protection command to restore the default state of BPDU
protection.
By default, BPDU protection is disabled.
Generally, the access ports of the access layer devices are directly connected to user
terminals (such as PC) or file servers. In this case, the access ports are set to edge
ports to implement fast state transition. However, when such access ports receive
configuration BPDU, the system will automatically set them to non-edge ports and
recalculate the spanning tree, which makes the network topology flap. These ports will
not receive any STP configuration BPDU in normal cases. Anyway, if someone
maliciously attacks the switch with fake configuration BPDU, the network will flap.
MSTP provides BPDU protection function to avoid such attack: After configured with
BPDU protection, the switch will disable the edge port through MSTP, which receives a
BPDU, and notify the network manager at same time. These ports can be resumed by
the network manager only.
Example
# Enable BPDU protection on the switch.
<Quidway>system-view
System View: return to User View with Ctrl+Z
[Quidway] stp bpdu-protection
1.1.13 stp bridge-diameter
Syntax
stp bridge-diameter bridgenum
undo stp bridge-diameter
View
System view
Parameter
bridgenum: Ranges from 2 to 7 and defaults to 7.