Enabling Loop Guard Or Root Guard On Specified Interfaces - Cisco Nexus 3000 Series Configuration Manual

Configuring STP Extensions
Step 2
This example shows how to enable Loop Guard on all spanning tree normal or network ports:
switch# configure terminal
switch(config)# spanning-tree loopguard default

Enabling Loop Guard or Root Guard on Specified Interfaces

You can enable either Loop Guard or Root Guard on specified interfaces.
Enabling Root Guard on a port means that port cannot become a root port, and LoopGuard prevents alternate
or root ports from becoming the designated port because of a failure that could lead to a unidirectional link.
Both Loop Guard and Root Guard enabled on an interface apply to all VLANs to which that interface belongs.
Entering the Loop Guard command for the specified interface overrides the global Loop Guard command.
Note
Before You Begin
Ensure that STP is configured.
Ensure that you are configuring Loop Guard on spanning tree normal or network ports.
Procedure
Step 1
Step 2
Step 3
OL-29545-03
Command or Action
switch(config)# spanning-tree
loopguard default
Command or Action
switch# configure terminal
switch(config)# interface type
slot/port
switch(config-if)# spanning-tree
guard {loop | root | none}
Cisco Nexus 3000 Series NX-OS Layer 2 Switching Configuration Guide, Release 6.x
Enabling Loop Guard or Root Guard on Specified Interfaces
Purpose
Enables Loop Guard by default on all spanning tree
normal and network ports. By default, global Loop
Guard is disabled.
Purpose
Enters global configuration mode.
Specifies the interface to configure, and enters the interface
configuration mode.
Enables or disables either Loop Guard or Root Guard for
the specified interface. By default, Root Guard is disabled
by default, and Loop Guard on specified ports is also
disabled.
Note Loop Guard runs only on spanning tree normal
and network interfaces.
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