Enabling Uplinkfast - Cisco 6500 Series Software Configuration Manual

Enabling UplinkFast

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
Portfast
PortFast BPDU Guard
Portfast BPDU Filter is enabled by default
Loopguard
UplinkFast
BackboneFast
Pathcost method used is long
Name
---------------------- -------- --------- -------- ---------- ----------
2 vlans
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 Catalyst 6500 series switch, decreasing the probability that the switch will become the
root bridge. The max_update_rate value represents the number of multicast packets transmitted per
second (the default is 150 packets per second). 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.
When you enable UplinkFast, it affects all VLANs on the Catalyst 6500 series switch. You cannot
Note
configure UplinkFast on an individual VLAN.
To enable UplinkFast, perform this task:
Command
Step 1
Router(config)# spanning-tree uplinkfast
[max-update-rate max_update_rate]
Router(config)# no spanning-tree uplinkfast
max-update-rate
Router(config)# no spanning-tree uplinkfast
Step 2
Router(config)# end
Step 3
Router# show spanning-tree vlan vlan_ID
This example shows how to enable UplinkFast with an update rate of 400 packets per second:
Router# configure terminal
Router(config)# spanning-tree uplinkfast max-update-rate 400
Router(config)# exit
Router#
Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
16-12
is disabled
is enabled by default
is disabled by default
is disabled by default
is disabled
is disabled
Blocking Listening Learning Forwarding STP Active
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Purpose
Enables UplinkFast.
Reverts to the default rate.
Disables UplinkFast.
Exits configuration mode.
Verifies that UplinkFast is enabled.
Chapter 16 Configuring Optional STP Features
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