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Enable BPDU Filtering Globally
The enabling of BPDU Filtering stops transmitting of BPDUs on the operational port fast enabled ports by default.
When BPDUs are received, the spanning tree is automatically prepared. By default global bpdu filtering is disabled.
Enable BPDU Filter globally to filter transmission of BPDU port fast enabled interfaces.
PROTOCOL SPANNING TREE RSTP mode
edge-port bpdu filter default
Figure 107. BPDU Filtering Enabled Globally
Modifying Interface Parameters
On interfaces in Layer 2 mode, you can set the port cost and port priority values.
● Port cost — a value that is based on the interface type. The previous table lists the default values. The greater the port
cost, the less likely the port is selected to be a forwarding port.
● Port priority — influences the likelihood that a port is selected to be a forwarding port in case that several ports have the
same port cost.
To change the port cost or priority of an interface, use the following commands.
● Change the port cost of an interface.
INTERFACE mode
spanning-tree rstp cost cost
The range is from 0 to 65535.
The default is listed in the previous table.
● Change the port priority of an interface.
INTERFACE mode
spanning-tree rstp priority priority-value
The range is from 0 to 240.
The default is 128.
To view the current values for interface parameters, use the show spanning-tree rstp command from EXEC privilege
mode.
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Rapid Spanning Tree Protocol (RSTP)