Example of the forward-delay ParameterTo view the current values for MSTP parameters, use the show running-config spanning-tree mstp command fromEXEC privilege mode.Dell(conf-mstp)#forward-delay 16Dell(conf-mstp)#exitDell(conf)#do show running-config spanning-tree mstp!protocol spanning-tree mstpno disablename my-mstp-regionMSTI 1 VLAN 100MSTI 2 VLAN 200-300forward-delay 16MSTI 2 bridge-priority 4096Dell(conf)#Modifying the Interface ParametersYou can adjust two interface parameters to increase or decrease the probability that a port becomes a forwarding port.• Port cost is a value that is based on the interface type. The greater the port cost, the less likely the port is selected to be aforwarding port.• Port priority influences the likelihood that a port is selected to be a forwarding port in case that several ports have the sameport cost.The following lists the default values for port cost by interface.Table 62. Default Values for Port Costs by InterfacePort Cost Default Value100-Mb/s Ethernet interfaces 2000001-Gigabit Ethernet interfaces 2000010-Gigabit Ethernet interfaces 2000Port Channel with 100 Mb/s Ethernet interfaces 180000Port Channel with 1-Gigabit Ethernet interfaces 18000Port Channel with 10-Gigabit Ethernet interfaces 1800To change the port cost or priority of an interface, use the following commands.1. Change the port cost of an interface.INTERFACE modespanning-tree msti number cost costThe range is from 0 to 200000.For the default, refer to the default values shown in the table..2. Change the port priority of an interface.INTERFACE modespanning-tree msti number priority priorityThe range is from 0 to 240, in increments of 16.The default is 128.550 Multiple Spanning Tree Protocol (MSTP)
