Alaxala AX3630S, Руководство пользователя программного обеспечения

Страница: 237 / 875

13. Spanning Tree Protocol
209
spanning-tree guard
Sets the guard functionality for the applicable ports. This command is applied to the applicable
ports of all Spanning Tree Protocols (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 }
If
loop
is set, the loop guard functionality is applied to the applicable ports. The loop guard
functionality does not operate for Multiple Spanning Tree.
If
none
is set, the guard functionality of the applicable port is stopped.
If
root
is set, 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
The setting of the
spanning-tree loopguard default
command is used.
Impact on communication
When loop guard functionality is set for a port or channel group that does not receive BPDU, even
after one such port comes up, communications of the port might remain disabled, or it might take
time until communication is enabled.
When the change is applied
When settings for the
spanning-tree portfast default
command or the
spanning-tree
portfast
command are deleted, if you change the configuration stored in memory without setting
the
spanning-tree portfast default
command or the
spanning-tree portfast
command, the
changes take effect immediately after the change.
Notes
1. If the
spanning-tree portfast default
command or the
spanning-tree portfast
command are set, the changes are not applied.
2. After the loop guard functionality is set, if the switch starts, a port (including a port in a
channel group) comes up, a Spanning Tree program is restarted, or the Spanning Tree type is
changed, then the loop guard functionality operates and the port is blocked. The loop guard
functionality is not cleared until a BPDU is received.
3. If loop guard functionality is set while a port is on line, the functionality is not enabled. Loop
guard functionality, set while a port is on line, is enabled when a BPDU reception timeout