Parameter
Default Setting
MSTP status
MSTP is enabled globally and on an interface.
Switching device priority
32768
Port priority
128
Algorithm used to calculate the
default path cost
dot1t, IEEE 802.1t
Forward Delay Time
1500 centiseconds
Hello Time
200 centiseconds
Max Age Time
2000 centiseconds
7.6 Configuring MSTP
This section describes the MSTP configuration.
7.6.1 Configuring Basic MSTP Functions
MSTP based on the basic STP/RSTP function divides a switching network into multiple regions,
each of which has multiple spanning trees that are independent of each other. MSTP isolates
different VLANs' traffic, and load-balances VLAN traffic.
Context
MSTP is commonly configured on switching devices to trim a ring network to a loop-free
network. Devices start spanning tree calculation after the working mode is set and MSTP is
enabled. Use any of the following methods if you need to intervene in the spanning tree
calculation:
l
Manually configure the root bridge and secondary root bridge.
l
Set a priority for a switching device in an MSTI: The lower the numerical value, the higher
the priority of the switching device and the more likely the switching device becomes a
root bridge; the higher the numerical value, the lower the priority of the switching device
and the less likely that the switching device becomes a root bridge.
l
Set a path cost for a port in an MSTI: With the same calculation method, the lower the
numerical value, the smaller the cost of the path from the port to the root bridge and the
more likely the port becomes a root port; the higher the numerical value, the larger the cost
of the path from the port to the root bridge and the less likely that the port becomes a root
port.
l
Set a priority for a port in an MSTI: The lower the numerical value, the more likely the port
becomes a designated port; the higher the numerical value, the less likely that the port
becomes a designated port.
Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
7 MSTP Configuration
Issue 01 (2014-11-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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