82To do... Use the command... RemarksEnter system view system-view —Enter Ethernet interfaceview or Layer 2 aggregateinterface viewinterface interface-typeinterface-numberEnter interfaceview or portgroup viewEnter port group view port-group manualport-group-nameRequiredUse either command.Configure the path cost of the ports stp [ instance instance-id ]cost costRequiredBy default, MSTPautomatically calculates thepath cost of each port.CAUTION:When the path cost of a port changes, MSTP re-calculates the role of the port and initiates a statetransition.Configuration example# Specify that the device use IEEE 802.1d-1998 to calculate the default path costs of its ports. system-view[Sysname] stp pathcost-standard dot1d-1998# Set the path cost of GigabitEthernet 1/0/3 on MSTI 2 to 200. system-view[Sysname] interface gigabitethernet 1/0/3[Sysname-GigabitEthernet1/0/3] stp instance 2 cost 200Configuring port priorityThe priority of a port is an important factor in determining whether the port can be elected as the rootport of a device. If all other conditions are the same, the port with the highest priority will be elected asthe root port.On an MSTP-enabled device, a port can have different priorities in different MSTIs, and the same portcan play different roles in different MSTIs, so that data of different VLANs can be propagated alongdifferent physical paths, implementing per-VLAN load balancing. You can set port priority values basedon the actual networking requirements.Make this configuration on the leaf nodes only.Follow these steps to configure the priority of a port or a group of ports:To do... Use the command... RemarksEnter system view system-view —Enter Ethernet interfaceview or Layer 2 aggregateinterface viewinterface interface-typeinterface-numberEnter interfaceview or portgroup viewEnter port group view port-group manualport-group-nameRequiredUse either command.
