You can only apply this command to a physical Ethernet interface.
Configuring the Rapid PVST+ Path-Cost Method and Port Cost
On access ports, you assign port cost by the port. On trunk ports, you assign the port cost by VLAN; you can
configure the same port cost on all the VLANs on a trunk.
In Rapid PVST+ mode, you can use either the short or long path-cost method, and you can configure the
method in either the interface or configuration submode.The default path-cost method is short.
Note
Procedure
Purpose
Command or Action
Enters global configuration mode.
switch#
configure terminal
Step 1
Selects the method used for Rapid PVST+ path-cost
calculations. The default method is the short method.
switch(config)#
spanning-tree
pathcost method
{
long
|
short
}
Step 2
Specifies the interface to configure, and enters interface
configuration mode.
switch(config)#
interface type
slot
/
port
Step 3
If this is a 10G breakout port, the
slot
/
port
syntax is
QSFP-module
/
port
.
Note
Configures the port cost for the LAN interface. The cost value,
depending on the path-cost calculation method, can be as
follows:
switch(config-if)#
spanning-tree
[
vlan vlan-id
]
cost
[
value
|
auto
]
Step 4
•
short
—
1 to 65535
•
long
—
1 to 200000000
You configure this parameter per interface on access
ports and per VLAN on trunk ports.
Note
The default is
auto
, which sets the port cost on both the
path-cost calculation method and the media speed.
This example shows how to configure the access port cost of an Ethernet interface:
switch#
configure terminal
switch (config)#
spanning-tree pathcost method long
switch (config)#
interface ethernet 1/4
switch(config-if)#
spanning-tree cost 1000
You can only apply this command to a physical Ethernet interface.
Configuring the Rapid PVST+ Bridge Priority of a VLAN
You can configure the Rapid PVST+ bridge priority of a VLAN.
Cisco Nexus 6000 Series NX-OS Layer 2 Switching Configuration Guide, Release 7.x
63
Configuring Rapid PVST+
Configuring the Rapid PVST+ Path-Cost Method and Port Cost
