2-715Cisco Catalyst Blade Switch 3120 for HP Command ReferenceOL-12248-03Chapter 2 Cisco Catalyst Blade Switch 3120 for HP Cisco IOS Commandsspanning-tree guardports. When the switch is operating in MST mode, BPDUs are not sent on nonboundary interfaces if theinterface is blocked by loop guard in all MST instances. On a boundary interface, loop guard blocks theinterface in all MST instances.To disable root guard or loop guard, use the spanning-tree guard none interface configurationcommand. You cannot enable both root guard and loop guard at the same time.You can override the setting of the spanning-tree loopguard default global configuration command byusing the spanning-tree guard loop interface configuration command.Examples This example shows how to enable root guard on all the VLANs associated with the specified port:Switch(config)# interface gigabitethernet2/0/2Switch(config-if)# spanning-tree guard rootThis example shows how to enable loop guard on all the VLANs associated with the specified port:Switch(config)# interface gigabitethernet2/0/2Switch(config-if)# spanning-tree guard loopYou can verify your settings by entering the show running-config privileged EXEC command.Related Commands Command Descriptionshow running-config Displays the operating configuration. For syntax information,use this link to the Cisco IOS Release 12.2 CommandReference listing page:http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/prod_command_reference_list.htmlSelect the Cisco IOS Commands Master List, Release 12.2to navigate to the command.spanning-tree cost Sets the path cost for spanning-tree calculations.spanning-tree loopguard default Prevents alternate or root ports from becoming designatedports because of a failure that leads to a unidirectional link.spanning-tree mst cost Configures the path cost for MST calculations.spanning-tree mst port-priority Configures an interface priority.spanning-tree mst root Configures the MST root switch priority and timers based onthe network diameter.spanning-tree port-priority Configures an interface priority.spanning-tree vlan priority Sets the switch priority for the specified spanning-treeinstance.
