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Software Configuration Guide—Release 15.0(2)SG
OL-23818-01
Chapter 21 Configuring Optional STP Features
Enabling BackboneFast
Figure 21-6 Adding a Switch in a Shared-Medium Topology
Enabling BackboneFast
Note For BackboneFast to work, you must enable it on all switches in the network. BackboneFast is supported
for use with third-party switches but it is not supported on Token Ring VLANs.
To enable BackboneFast, perform this task:
This example shows how to enable BackboneFast:
Switch(config)# spanning-tree backbonefast
Switch(config)# end
Switch#
This example shows how to verify that BackboneFast is enabled:
Switch# show spanning-tree backbonefast
BackboneFast is enabled
BackboneFast statistics
-----------------------
Number of transition via backboneFast (all VLANs) : 0
Number of inferior BPDUs received (all VLANs) : 0
Switch A
(Root)
Switch C Switch B
(Designated Bridge)
Added switch
11245
Blocked port
Command Purpose
Step 1 Switch(config)# [no] spanning-tree backbonefast Enables BackboneFast.
Use You can use the no keyword to disable
BackboneFast.
Step 2 Switch(config)# end Exits configuration mode.
Step 3 Switch# show spanning-tree backbonefast Verifies that BackboneFast is enabled.