Enabling Cross-Stack Uplinkfast; Enabling Backbonefast; Enabling Etherchannel Guard - Cisco Catalyst 2975 Software Configuration Manual

Chapter 18 Configuring Optional Spanning-Tree Features

Enabling Cross-Stack UplinkFast

When you enable or disable the UplinkFast feature by using the spanning-tree uplinkfast global
configuration command, CSUF is automatically globally enabled or disabled on nonstack port
interfaces.
For more information, see the
page
To disable UplinkFast on the switch and all its VLANs, use the no spanning-tree uplinkfast global
configuration command.

Enabling BackboneFast

You can enable BackboneFast to detect indirect link failures and to start the spanning-tree
reconfiguration sooner.
If you use BackboneFast, you must enable it on all switches in the network. BackboneFast is not
Note
supported on Token Ring VLANs. This feature is supported for use with third-party switches.
You can configure the BackboneFast feature for rapid PVST+ or for the MSTP, but the feature remains
disabled (inactive) until you change the spanning-tree mode to PVST+.
Beginning in privileged EXEC mode, follow these steps to enable BackboneFast. This procedure is
optional.
Command
Step 1 configure terminal
Step 2
spanning-tree backbonefast
Step 3
end
Step 4 show spanning-tree summary
Step 5 copy running-config startup-config
To disable the BackboneFast feature, use the no spanning-tree backbonefast global configuration
command.

Enabling EtherChannel Guard

You can enable EtherChannel guard to detect an EtherChannel misconfiguration if your switch is
running PVST+, rapid PVST+, or MSTP.
OL-19720-02
"Enabling UplinkFast for Use with Redundant Links" section on
18-16.
Configuring Optional Spanning-Tree Features
Purpose
Enter global configuration mode.
Enable BackboneFast.
Return to privileged EXEC mode.
Verify your entries.
(Optional) Save your entries in the configuration file.
Catalyst 2975 Switch Software Configuration Guide
18-17