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spanning-tree cost
This command configures the spanning tree path cost for the specified
interface. Use the no form to restore the default.
Syntax
spanning-tree cost cost
no spanning-tree cost
cost - The path cost for the port.
(Range: 0 for auto-configuration, or 1-200,000,000)
The recommended range is:
• Ethernet: 200,000-20,000,000
• Fast Ethernet: 20,000-2,000,000
• Gigabit Ethernet: 2,000-200,000
• 10 Gigabit Ethernet: 200-20,000
Default Setting
By default, the system automatically detects the speed and duplex mode
used on each port, and configures the path cost according to the values
shown below. Path cost “0” is used to indicate auto-configuration mode.
• Ethernet – half duplex: 2,000,000; full duplex: 1,000,000; trunk: 500,000
• Fast Ethernet – half duplex: 200,000; full duplex: 100,000; trunk: 50,000
• Gigabit Ethernet – full duplex: 10,000; trunk: 5,000
• 10 Gigabit Ethernet – full duplex: 1000; trunk: 500
Command Mode
Interface Configuration (Ethernet, Port Channel)
Command Usage
• This command is used by the Spanning Tree Algorithm to determine the
best path between devices. Therefore, lower values should be assigned to
ports attached to faster media, and higher values assigned to ports with
slower media.
• Path cost takes precedence over port priority.
• When the spanning-tree pathcost method (page 4-228) is set to short, the
maximum value for path cost is 65,535.