Cisco Catalyst 2950 Command Reference Manual page 306

spanning-tree uplinkfast
If you set the max-update-rate to 0, station-learning frames are not generated, so the spanning-tree
topology converges more slowly after a loss of connectivity.
Examples
This example shows how to enable UplinkFast:
Switch(config)# spanning-tree uplinkfast
You can verify your setting by entering the show spanning-tree summary privileged EXEC command.
Related Commands Command
show spanning-tree
spanning-tree stack-port
spanning-tree vlan
Catalyst 2950 Desktop Switch Command Reference
2-282
Description
summary Displays a summary of the spanning-tree port states.
Enables cross-stack UplinkFast (CSUF) on an interface and
accelerates the choice of a new root port when a link or switch
fails or when spanning tree reconfigures itself.
root primary Forces this switch to be the root switch.
Chapter 2 Cisco IOS Commands
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