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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 21 Configuring Optional STP Features Enabling UplinkFast
Note When you enable UplinkFast, it affects all VLANs on the switch. You cannot configure UplinkFast on
an individual VLAN.
To enable UplinkFast, perform this task:
This example shows how to enable UplinkFast with a maximum update rate of 400 pps:
Switch(config)# spanning-tree uplinkfast max-update-rate 400
Switch(config)# exit
Switch#
This example shows how to verify which VLANS have UplinkFast enabled:
Switch# show spanning-tree uplinkfast
UplinkFast is enabled
Station update rate set to 150 packets/sec.
UplinkFast statistics
-----------------------
Number of transitions via uplinkFast (all VLANs) :14
Number of proxy multicast addresses transmitted (all VLANs) :5308
Name Interface List
-------------------- ------------------------------------
VLAN1 Fa6/9(fwd), Gi5/7
VLAN2 Gi5/7(fwd)
VLAN3 Gi5/7(fwd)
VLAN4
VLAN5
VLAN6
VLAN7
VLAN8
VLAN10
VLAN15
VLAN1002 Gi5/7(fwd)
VLAN1003 Gi5/7(fwd)
VLAN1004 Gi5/7(fwd)
VLAN1005 Gi5/7(fwd)
Switch#
Command Purpose
Step 1 Switch(config)# [no] spanning-tree uplinkfast
[max-update-rate max_update_rate] Enables UplinkFast.
Use the no keyword to disable UplinkFast and restore the
default rate, use the command.
Step 2 Switch(config)# end Exits configuration mode.
Step 3 Switch# show spanning-tree vlan vlan_ID Verifies that UplinkFast is enabled on that VLAN.