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Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
OL-8978-04
Chapter 7 Configuring Spanning Tree
Configuring PVST+ on the Switch
•
The long mode has these parameters:
–
Portcost
–
Portvlancost (trunk ports only)
–
When UplinkFast is enabled, the actual cost is incremented by 10,000,000
–
EtherChannel computes the cost of a bundle using the formula,
AVERAGE_COST/NUM_PORT
The default port cost mode is set to short in PVST+ mode. For port speeds of 10 Gb and greater, the
default port cost mode must be set to long.
To configure the PVST+ default port cost mode, perform this task in privileged mode:
This example shows how to configure the PVST+ default port cost mode:
Console> (enable)
set spantree defaultcostmode long
Portcost and portvlancost set to use long format default values.
Console> (enable)
Task
Command
Configure the PVST+ default port cost mode.
set spantree defaultcostmode
{
short
|
long
}