Cisco Catalyst 250 Series Command Reference

spanning-tree loopguard default
To enable loop guard as a default on all ports of a given bridge, use the spanning-tree loopguard default
command in global configuration mode. To disable loop guard, use the no form of this command.
spanning-tree loopguard default
no spanning-tree loopguard default
Syntax Description
This command has no arguments or keywords.
Command Default
Loop guard is disabled.
Command Modes
Global configuration
Command History
ModificationRelease
This command was introduced.Cisco IOS 15.0(2)EX
Usage Guidelines
Loop guard provides additional security in the bridge network. Loop guard prevents alternate or root ports
from becoming the designated port due to a failure that could lead to a unidirectional link.
Loop guard operates only on ports that are considered point-to-point by the spanning tree.
The individual loop-guard port configuration overrides this command.
Examples
This example shows how to enable loop guard:
Switch(config)# spanning-tree loopguard default
Related Commands
DescriptionCommand
Enables root guard or loop guard.
spanning-tree guard
Catalyst 2960-X Switch Layer 2 Command Reference, Cisco IOS Release 15.0(2)EX
OL-29043 -01 89
Layer 2 Commands
spanning-tree loopguard default

Cisco Catalyst 250 Series Specifications

General

Brand	Cisco
Model	Catalyst 250 Series
Category	Switch
Language	English