Mstp Troubleshooting - Digitalchina Networks DCS-3950 series Manual

10.4.2 MSTP Troubleshooting

In order to run the MSTP on the switch port, the MSTP has to be enabled
globally. If the MSTP is not enabled globally, it can't be enabled on the port.
The MSTP parameters co work with each other, so the parameters should
meet the following conditions. Otherwise, the MSTP may work incorrectly.
2×(Bridge_Forward_Delay -1.0 seconds) >= Bridge_Max_Age
Bridge_Max_Age >= 2 ×(Bridge_Hello_Time + 1.0 seconds)
When users modify the MSTP parameters, they have to be sure about the
changes of the topologies. The global configuration is based on the bridge.
Other configurations are based on the individual instances.
The MSTP are mutually exclusive with MAC binding and IEEE 802.1x on the
switch port. If MAC binding or IEEE 802.1x is enabled on the port, the MSTP
can't apply to this port.
DCS-3950 series Ethernet switch manual
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