21-12
Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX
OL-4266-08
Chapter 21 Configuring Optional STP Features
Enabling BPDU Guard
Enabling BPDU Guard
To enable BPDU Guard globally, perform this task:
This example shows how to enable BPDU Guard:
Router#
configure terminal
Router(config)#
spanning-tree portfast bpduguard
Router(config)#
end
Router#
This example shows how to verify the configuration:
Router#
show spanning-tree summary totals
default
Root bridge for:VLAN0010
EtherChannel misconfiguration guard is enabled
Extended system ID is disabled
Portfast is enabled by default
PortFast BPDU Guard is disabled by default
Portfast BPDU Filter is enabled by default
Loopguard is disabled by default
UplinkFast is disabled
BackboneFast is disabled
Pathcost method used is long
Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
2 vlans 0 0 0 3 3
Router#
Enabling UplinkFast
UplinkFast increases the bridge priority to 49152 and adds 3000 to the STP port cost of all Layer 2 LAN
interfaces on the Cisco 7600 series router, decreasing the probability that the router will become the root
bridge. UplinkFast cannot be enabled on VLANs that have been configured for bridge priority. To enable
UplinkFast on a VLAN with bridge priority configured, restore the bridge priority on the VLAN to the
default value by entering a
no spanning-tree vlan
vlan_ID
priority
command in global configuration
mode.
Note
When you enable UplinkFast, it affects all VLANs on the Cisco 7600 series router. You cannot configure
UplinkFast on an individual VLAN.
To enable UplinkFast, perform this task:
Command
Purpose
Step 1
Router(config)#
spanning-tree portfast bpduguard
default
Router(config)#
no spanning-tree portfast
bpduguard
default
Enables BPDU Guard globally.
Disables BPDU Guard globally.
Step 2
Router(config)#
end
Exits configuration mode.
Step 3
Router#
show spanning-tree
summary totals
Verifies the configuration.