H3C Technologies H3C S12500-X Series Switches - Manual (Page 104)

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Configuration procedure
# Enable No Agreement Check on Ten-GigabitEthernet 1/0/1 of Device A.
system-view
[DeviceA] interface ten-gigabitethernet 1/0/1
[DeviceA-Ten-GigabitEthernet1/0/1] stp no-agreement-check
Configuring protection functions
A spanning tree device supports the following protection functions:
• BPDU guard
• Root guard
• Loop guard
• Port role restriction
• TC-BPDU transmission restriction
• TC-BPDU guard
Enabling BPDU guard
For access layer devices, the access ports can directly connect to the user terminals (such as PCs) or file
servers. The access ports are configured as edge ports to allow rapid transition. When these ports
receive configuration BPDUs, the system automatically sets the ports as non-edge ports and starts a new
spanning tree calculation process. This causes a change of network topology. Under normal conditions,
these ports should not receive configuration BPDUs. However, if someone forges configuration BPDUs
maliciously to attack the devices, the network will become unstable.
The spanning tree protocol provides the BPDU guard function to protect the system against such attacks.
With the BPDU guard function enabled on the devices, when edge ports receive configuration BPDUs,
the system closes these ports and notifies the NMS that these ports have been closed by the spanning tree
protocol. The device reactivates the closed ports after a detection interval. For more information about
this detection interval, see Fundamentals Configuration Guide.
BPDU guard does not take effect on loopback-testing-enabled ports. For more information about
loopback testing, see "Configuring Ethernet interfaces."
Configure BPDU guard on a device with edge ports configured.
To enable BPDU guard:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enable the BPDU guard
function for the device.
stp bpdu-protection
By default, BPDU guard is
disabled.
Enabling root guard
The root bridge and secondary root bridge of a spanning tree should be located in the same MST region.
Especially for the CIST, the root bridge and secondary root bridge are put in a high-bandwidth core