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Spanning-tree port-priority – SMC Networks SMC Tiger 10/100 SMC6128PL2 User Manual

Page 518

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Command Line Interface

4-210

4

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 4-204) is set to short, the

maximum value for path cost is 65,535.

Example

spanning-tree port-priority

This command configures the priority for the specified interface. Use the no form to
restore the default.

Syntax

spanning-tree port-priority priority
no spanning-tree port-priority

priority - The priority for a port. (Range: 0-240, in steps of 16)

Default Setting

128

Command Mode

Interface Configuration (Ethernet, Port Channel)

Console(config)#interface ethernet 1/5
Console(config-if)#spanning-tree cost 50
Console(config-if)#