Stp Root-Protection - Huawei Quidway S8500 Series Command Manual

Command Manual – STP
Quidway S8500 Series Routing Switches
You can configure one or more secondary root bridges in an MSTI. If the primary root is
down or powered off, the secondary root will take its place. Among several secondary
root bridges, the one with the smallest MAC address takes the place of the failed
primary root.
When configuring the secondary root bridge, you may also specify the switching
network diameter and the Hello Time of the switch, so that the other two parameters,
Forward Delay and Max Age, of the switch can be determined. To configure the current
switch as the root bridge of CIST, simply specify instance-id as 0. You can configure
only one root bridge for an MSTI and one or more secondary root bridges for it.
After a switch is configured as a primary root bridge or a secondary root bridge, users
cannot modify the bridge priority of the switch.
Example
# Configure the current switch as the secondary root bridge of MSTI 0 and specify the
diameter of the switching network as 5 and the Hello Time of the switch as 300
centiseconds.
<Quidway>system-view
System View: return to User View with Ctrl+Z.
[Quidway] stp instance 0 root primary bridge-diameter 5 hello-time 300

1.1.36 stp root-protection

Syntax
stp root-protection
undo stp root-protection
View
Ethernet port view
Parameter
None
Description
Use the stp root-protection command to enable on Root protection the switch.
Use the undo stp root-protection command to restore the default state of Root
protection.
By default, Root protection is disabled.
In case of configuration error or malicious attack, the legal primary root may receive the
BPDU with a higher priority and then loose its place, which causes network topology
change errors. Due to the illegal change, the traffic supposed to travel over the
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Chapter 1 MSTP Configuration Commands