Specifications

spanning-tree guard
160
spanning-tree guard
Sets the guard functionality for the applicable ports. This command is applied to the
applicable PVST+, Single Spanning Tree, and Multiple Spanning Tree.
Syntax
To set or change information:
spanning-tree guard { loop | none | root }
To delete information:
no spanning-tree guard
Input mode
(config-if)
Parameters
{ loop | none | root }
loop: The loop guard functionality is applied to the applicable ports. The loop guard
functionality does not operate for Multiple Spanning Tree.
none: Stop operation of the loop guard functionality and root guard functionality for
the applicable ports.
root:The root guard functionality is applied to the applicable ports.
1. Default value when this parameter is omitted:
This parameter cannot be omitted.
2. Range of values:
loop, none, or root
Default behavior
For the loop guard functionality: The setting of the spanning-tree loopguard default
command is used.
For the root guard functionality: The command does not operate.
Impact on communication
None
When the change is applied
Loop guard setting:
 When the
spanning-tree portfast default command or the
spanning-tree portfast command is set, the loop guard setting is not
applied.
 If the
spanning-tree portfast default command and spanning-tree
portfast command settings have been deleted, loop guard operation starts
immediately.
Root guard setting:
 The change takes effect immediately after it is made.
Notes
1. When the spanning-tree portfast default command or the spanning-tree
portfast
command is set, the loop guard setting is not applied. Instead, the root