Huawei quidway s7700 Configuration Guide - Ethernet

l RSTP uses a single spanning tree instance on the entire network, which cannot prevent the
performance from deteriorating when the network scale grows. Therefore, the network
diameter cannot be larger than 7.
l It is recommended that you run the stp bridge-diameter diameter command to set the
network diameter. Then, the switching device calculates the optimal Forward Delay period,
Hello time, and Max Age period based on the set network diameter.
Step 4 Run:
stp timer-factor factor
The timeout period for waiting for BPDUs from the upstream of a switching device is set.
By default, the timeout period of a switching device is 9 times as long as the Hello time.
Step 5 (Optional) To set the Forward Delay period, Hello time, and Max Age period, perform the
following operations:
l Run the stp timer forward-delay forward-delay command to set the Forward Delay period
for a switching device.
The default Forward Delay period of a switching device is 1500, in centiseconds.
l Run the stp timer hello hello-time command to set the Hello time for a switching device.
The default Hello time of a switching device is 200, in centiseconds.
l Run the stp timer max-age max-age command to set the Max Age period for a switching
device.
The default Max Age period of a switching device is 2000, in centiseconds.
NOTE
The values of the Hello time, Forward Delay period, and Max Age period must comply with the following
formulas. Otherwise, networking flapping occurs.
l 2 × (Forward Delay - 1.0 second) >= Max Age
l Max Age >= 2 × (Hello Time + 1.0 second)
Step 6 Run:
stp max-hops hop
The maximum hop count is set for the MST region.
By default, the maximum hop count of the MST region is 20.
Step 7 Run:
stp mcheck
MCheck is enabled.
On a switching device running MSTP, if an interface is connected to a device running STP, the
interface automatically transitions to the STP mode.
Enabling MCheck on the interface is required because the interface may fail to automatically
transition to the MSTP mode in the following situations:
l The switching device running STP is shut down or moved.
l The switching device running STP transitions to the MSTP mode.
Quidway S7700 Smart Routing Switch
Configuration Guide - Ethernet 9 MSTP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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Huawei quidway s7700 Specifications

General

Brand	Huawei
Model	quidway s7700
Category	Network Router
Language	English