FTOS Configuration Guide for the C-Series - Force10 Networks

Table 41 E-Series Port Cost Values
FTOS Default Port Cost Values (IEEE MST) Values
Port Channel interface with one 100 Mb/s Ethernet 200000
Port Channel interface with one 1-Gigabit Ethernet 20000
Port Channel interface with one 10-Gigabit Ethernet 2000
Port Channel with two 1-Gigabit Ethernet 18000
Port Channel with two 10-Gigabit Ethernet 1800
Port Channel with two 100-Mbps Ethernet 180000
The following command configures the port cost of the interface:
Command Syntax Command Mode Usage
spanning-tree pvst vlan
vlan-range cost number
To change the port cost of an interface, use the spanning-tree pvst vlan cost command in the
INTERFACE mode, as shown below:
Figure 282 Configuring PVST+ Port Cost
Configuring port priority
INTERFACE (OPTIONAL) Enter the keyword cost followed by the
port cost value.
Range: 1 to 200000
Defaults:
100 Mb/s Ethernet interface = 200000
1-Gigabit Ethernet interface = 20000
10-Gigabit Ethernet interface = 2000
Port Channel interface with 100 Mb/s Ethernet =
200000
Port Channel interface with 1-Gigabit Ethernet = 20000
Port Channel interface with 10-Gigabit Ethernet = 2000
Port Channel with 2 1-Gigabit Ethernet = 18000
Port Channel with 2 10-Gigabit Ethernet = 1800
Port Channel with 2 100-Mbps Ethernet = 180000
Force10#conf
Force10(conf)#interface gigabitethernet 1/1
Force10(conf-if-gi-1/1)#spanning-tree pvst vlan 3 cost 18000
Port priority determines the likelihood that the port will be selected to transmit traffic.
402 Per-VLAN Spanning Tree Plus