The default is 20 seconds.To view the current values for global parameters, use the show spanning-tree rstp command from EXEC privilege mode.Enabling SNMP Traps for Root Elections and TopologyChangesTo enable SNMP traps, use the following command.• Enable SNMP traps for RSTP, MSTP, and PVST+ collectively.snmp-server enable traps xstpModifying Interface ParametersOn 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 lesslikely 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 portcost.To change the port cost or priority of an interface, use the following commands.• Change the port cost of an interface.INTERFACE modespanning-tree rstp cost costThe range is from 0 to 65535.The default is listed in the previous table.• Change the port priority of an interface.INTERFACE modespanning-tree rstp priority priority-valueThe range is from 0 to 15.The default is 128.To view the current values for interface parameters, use the show spanning-tree rstp command from EXEC privilege mode.Enabling SNMP Traps for Root Elections and TopologyChangesTo enable SNMP traps collectively, use this command.Enable SNMP traps for RSTP, MSTP, and PVST+ collectively.750 Rapid Spanning Tree Protocol (RSTP)
