Administrator Guide

Layer 2 Switching Commands 766
no spanning-tree cost
• cost — The port path cost. (Range: 1–200,000,000)
Default Configuration
The default value is to select the path cost based on the link speed.
• 40G Port path cost — 1400
•
10G Port path cost — 2000
•
1000 mbps (giga) — 20,000
•
100 mbps — 200,000
•
10 mbps — 2,000,000
• Port Channel—200,000,000 divided by the sum of the unidirectional link
speed (in Mbps) of each active member multiplied by 10 per section 13.6.1
of IEEE
802.1 s.
Command Mode
Interface Configuration (gigabitethernet, port-channel, tengigabitethernet,
fortygigabitethernet) mode
User Guidelines
If the VLAN parameter is given, the path cost is configured only for the
selected VLANs (applies only when pvst or rapid-pvst mode is selected).
Configuration without the VLAN parameter configures the interface path
cost for RSTP, RSTP-PV, and STP-PV.
If an interface is configured with both the spanning-tree vlan
vlan-id cost cost
command and the spanning-tree cost
cost command, the spanning-tree vlan
vlan-id
cost cost value is used in the spanning tree calculation.
Example
The following example configures the external path cost to be 8192 for
VLANs 12, 13, 24, 25, and 26.
console(config-if-Gi1/0/1)#spanning-tree vlan 12,13,24-26 cost 8192
2CSNXXX_SWUM204.book Page 766 Monday, January 25, 2016 1:25 PM