Users Guide

spanning-tree
Assigns a Layer 2 interface to STP instance 0 and configures a port cost or port priority, or enables loop
guard, root guard, or the Portfast feature on the interface.
Syntax
spanning-tree stp-id {cost cost | {loopguard | rootguard} |
portfast [bpduguard [shutdown-on-violation]] | priority priority}
To disable Spanning Tree group on an interface, use the no spanning-tree stp-id
{cost cost | {loopguard | rootguard} | portfast [bpduguard
[shutdown-on-violation]] | priority priority} command.
Parameters
stp-id Enter the STP instance ID. The range is 0.
cost cost Enter the keyword cost then a number as the cost. The range is
from 1 to 65535. The defaults are:
• 1-Gigabit Ethernet interface = 4.
• 10-Gigabit Ethernet interface = 2.
• Port Channel interface with 100 Mb/s Ethernet = 18.
• Port Channel interface with 1 Gigabit Ethernet = 3.
• Port Channel interface with 10 Gigabit Ethernet = 1.
loopguard Enter the keyword loopguard to enable STP loop guard on a
port or port-channel interface.
rootguard Enter the keyword rootguard to enable STP root guard on a
port or port-channel interface.
portfast
[bpduguard
[shutdown-on-
viol ation]]
Enter the keyword portfast to enable Portfast to move the
interface into Forwarding mode immediately after the root fails.
Enter the optional keyword bpduguard to disable the port when
it receives a BPDU.
Enter the optional keyword shutdown-on-violation to
hardware disable an interface when a BPDU is received and the
port is disabled.
priority priority Enter keyword priority then a number as the priority. The
range is from zero (0) to 15. The default is 8.
Defaults cost = depends on the interface type; priority = 8
Command Modes INTERFACE
Spanning Tree Protocol (STP) 1952