T3700G-28TQ
 
JetStream 28-Port Gigabit Stackable L3 Managed Switch CLI Guide 
 
218 
no spanning-tree bpduguard 
Command Mode 
Interface Configuration Mode (interface fastEthernet / interface range 
fastEthernet / interface gigabitEthernet / interface range gigabitEthernet/ 
interface ten-gigabitEthernet / interface range ten-gigabitEthernet) 
Example 
Enable the BPDU protect function for Gigabit Ethernet port 1/0/2: 
T3700G-28TQ(config)#interface gigabitEthernet 1/0/2 
T3700G-28TQ(config-if)#spanning-tree bpduguard 
spanning-tree guard loop 
Description 
The spanning-tree guard loop command is used to enable the Loop Protect 
function for a port. Loop Protect is to prevent the loops in the network brought by 
recalculating STP because of link failures and network congestions. To disable 
the Loop Protect function, please use no spanning-tree guard loop command. 
Syntax 
spanning-tree guard loop 
no spanning-tree guard loop 
Command Mode 
Interface Configuration Mode (interface fastEthernet / interface range 
fastEthernet / interface gigabitEthernet / interface range gigabitEthernet/ 
interface ten-gigabitEthernet / interface range ten-gigabitEthernet) 
Example 
Enable the Loop Protect function for Gigabit Ethernet port 1/0/2: 
T3700G-28TQ(config)#interface gigabitEthernet 1/0/2 
T3700G-28TQ(config-if)#spanning-tree guard loop 
spanning-tree guard root 
Description 
The  spanning-tree guard root command is used to enable the Root Protect 
function for a port. With the Root Protect function enabled, the root bridge will