Configuring the Spanning Tree Protocol 641Configuring MSTP Interface SettingsBeginning in Privileged EXEC mode, use the following commands toconfigure MSTP settings for the switch.Command Purposeconfigure Enter global configuration mode.interfaceinterface Enter interface configuration mode for the specified interface.Theinterface variable includes the interface type and number,for example tengigabitethernet 1/0/3 or port-channel 4.You can also specify a range of interfaces with the interfacerange command, for example, interface rangetengigabitethernet 1/0/8-12 configures interfaces 8, 9, 10, 11,and 12. The range keyword is also valid for LAGs (portchannels).spanning-tree mst 0external-costcostSet the external cost for the common spanning tree. (Range:0–200000000)spanning-tree mstinstance-id costcostConfigure the path cost for MST calculations. If a loop occurs,the spanning tree considers path cost when selecting aninterface to put in the forwarding state.•instance-ID — ID of the spanning -tree instance. (Range: 1-4094)•cost — The port path cost. (Range: 0–200,000,000)spanning-tree mstinstance-id port-priorityprioritySpecify the priority of the port.The priority value is used to determine which ports are put inthe forwarding state and which ports are put in the blockingstate. A port with a lower priority value is more likely to be putinto a forwarding state.•instance-ID — ID of the spanning-tree instance. (Range: 1-4094)•priority — The port priority. (Range: 0–240 in multiples of 16)CTRL + Z Exit to Privileged EXEC mode.show spanning-treeinterface instanceinstance-idView MST configuration information for the specified port orLAG (port channel) and instance.
