Chapter 17
| Spanning Tree Commands
– 425 –
Related Commands
spanning-tree edge-port (426)
spanning-tree spanning-disabled (434)
spanning-tree cost
This command configures the spanning tree path cost for the specified
interface. Use the
no
form to restore the default auto-configuration mode.
Syntax
spanning-tree
cost
cost
no spanning-tree cost
cost
- The path cost for the port. (Range: 0 for auto-configuration,
1-65535 for short path cost method, 1-200,000,000 for long path
cost method)
‡‡‡
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. When the
short path cost method is selected and the default path cost recommended by
the IEEE 8021w standard exceeds 65,535, the default is set to 65,535.
Command Mode
Interface Configuration (Ethernet, Port Channel)
Table 85: Recommended STA Path Cost Range
Port Type
Short Path Cost
(IEEE 802.1D-1998)
Long Path Cost
(IEEE 802.1D-2004)
Ethernet
50-600
200,000-20,000,000
Fast Ethernet
10-60
20,000-2,000,000
Gigabit Ethernet
3-10
2,000-200,000
10G Ethernet
1-5
200-20,000
‡‡‡.Use the
command to set the path cost method. The range
displayed in the CLI prompt message shows the maximum value for path cost. However,
note that the switch still enforces the rules for path cost based on the specified path cost
method (long or short).
Table 86: Default STA Path Costs
Port Type
Short Path Cost
(IEEE 802.1D-1998)
Long Path Cost
(IEEE 802.1D-2004)
Ethernet
65,535
1,000,000
Fast Ethernet
65,535
100,000
Gigabit Ethernet
10,000
10,000
10G Ethernet
1,000
1,000
