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Cisco ME 3400 EthernetAccess Switch SoftwareConfiguration Guide
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Chapter16 Configuring Optional Spanning-Tree Features
Displaying the Spanning-Tree Status
Note You cannot enable both loop guard and root guard at the same time.
You can enable this feature if your switch is running PVST+, rapid PVST+, or MST P.
Beginning in privileged EXEC mode, follow these steps to enable loop guard. This procedure is optional.
To globally disable loop guard, use the no spanning-tree loopguard default global configuration
command. You can override the setting of the no spanning-tree loopguard def ault global configuration
command by using the spanning-tree guard loop interface configuration command on an NNI.
Displaying the Spanning-Tree Status
To display the spanning-tree status, use one or more of the privileged EXEC commands in Table16-2:
You can clear spanning-tree counters by using the clear spanning-tree [interface interface-id]
privileged EXEC command.
For information about other keywords for the show spanning-tree privileged EXEC command, see the
command reference for this release.
Command Purpose
Step1 show spanning-tree active
or
show spanning-tree mst
Verify which interfaces are alternate or root ports.
Step2 configure terminal Enter global configuration mode.
Step3 spanning-tree loopguard default Enable loop guard. By default, loop guard is disabled.
Step4 end Return to privileged EXEC mode.
Step5 show running-config Verify your entries.
Step6 copy running-config startup-config (Optional) Save your entries in the configuration file.
Table16-2 Commands for Displaying the Spanning-Tree Status
Command Purpose
show spanning-tree active Displays spanning-tree information on active interfaces only.
show spanning-tree detail Displays a detailed summary of interface information.
show spanning-tree interface interface-id Displays spanning-tree information for the specified interface.
show spanning-tree mst interface interface-id Displays MST information for the specified interface.
show spanning-tree summary [totals] Displays a summary of interface states or displays the total lines of the
spanning-tree state section.