Enabling Loop Guard Globally - Cisco Nexus 3000 series Configuration Manual

Configuring STP Extensions
When you enable BPDU Filtering locally on a port, this feature prevents the device from receiving or
Note
sending BPDUs on this port.
Before You Begin
Ensure that STP is configured.
SUMMARY STEPS
1. switch# configure terminal
2. switch(config)# interface type slot/port
3. switch(config-if)# spanning-tree bpdufilter {enable | disable}
4. (Optional) switch(config-if)# no spanning-tree bpdufilter
DETAILED STEPS
Command or Action
Step 1 switch# configure terminal
Step 2 switch(config)# interface type slot/port
Step 3
switch(config-if)# spanning-tree bpdufilter
{enable | disable}
Step 4 switch(config-if)# no spanning-tree
bpdufilter
This example shows how to explicitly enable BPDU Filtering on the Ethernet spanning tree edge port 1/4:
switch# configure terminal
switch (config)# interface ethernet 1/4
switch(config-if)# spanning-tree bpdufilter enable

Enabling Loop Guard Globally

You can enable Loop Guard globally by default on all point-to-point spanning tree normal and network ports.
Loop Guard does not run on edge ports.
Loop Guard provides additional security in the bridge network. Loop Guard prevents alternate or root ports
from becoming the designated port because of a failure that could lead to a unidirectional link.
Cisco Nexus 3000 Series NX-OS Layer 2 Switching Configuration Guide, Release 5.0(3)U1(1)
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Purpose
Enters configuration mode.
Specifies the interface to configure, and enters the interface
configuration mode.
Enables or disables BPDU Filtering for the specified spanning tree
edge interface. By default, BPDU Filtering is disabled.
(Optional)
Disables BPDU Filtering on the interface.
Enables BPDU Filtering on the interface if the interface is an
Note
operational spanning tree edge port and if you enter the
spanning-tree port type edge bpdufilter default command.
Configuring STP Extensions