Configuring PVST+ on the Switch
The long mode has these parameters:
•
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:
Task
Configure the PVST+ default port cost 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)
Catalyst 6500 Series Switch Software Configuration Guide—Release 8.7
7-30
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
Chapter 7
Command
set spantree defaultcostmode {short | long}
Configuring Spanning Tree
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