Optional) Configuring The Root Bridge And Secondary Root Bridge - Huawei AR530 series Configuration Manual

Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
MST region configurations are activated so that the configured region name, VLAN-to-instance
mappings, and revision number can take effect.
If this step is not done, the preceding configurations cannot take effect.
If you have changed MST region configurations on the switching device after MSTP starts, run
the active region-configuration command to activate the MST region so that the changed
configurations can take effect.
----End

7.6.1.3 (Optional) Configuring the Root Bridge and Secondary Root Bridge

Context
The root bridge can be calculated through calculation. You can also manually configure the root
bridge or secondary root bridge.
l
l
l
Procedure
l
l
Issue 01 (2014-11-30)
A switching device plays different roles in different spanning trees. The switching device
can function as the root switch or secondary root switch of a spanning tree and the root
switch or secondary root switch of another spanning tree. The switching device can function
as only the root switch or secondary root switch of the same spanning tree.
In a spanning tree, only one root bridge takes effect. When two or more than two devices
are specified as root bridges of a spanning tree, the device with the smallest MAC address
is used as the root bridge.
You can specify multiple secondary root bridges for each spanning tree. When the root
bridge fails or is powered off, the secondary root bridge becomes the new root bridge. If a
new root bridge is specified, the secondary root bridge will not become the root bridge. If
multiple secondary root bridges are configured, the secondary root bridge with smallest
MAC address will become the root bridge of the spanning tree.
NOTE
It is recommended that the root bridge and secondary root bridge be configured manually.
Perform the following operations on the device to be used as the root bridge.
1. Run:
system-view
The system view is displayed.
2. Run:
stp [ instance instance-id ] root primary
The device is configured as the root bridge.
By default, a switching device does not function as the root bridge. After the
configuration is complete, the BID of the device is 0 and cannot be changed.
If instance is not specified, the device in MSTI 0 is a root bridge.
Perform the following operations on the device to be used as the secondary root bridge.
1. Run:
system-view
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
7 MSTP Configuration
246