Catalyst 3750 Command Reference, Release 12.2(55)SE - Catalyst 3750 Switch Cisco IOS Commands - shut

Usage Guidelines You can configure the BackboneFast feature for rapid PVST+ or for multiple spanning-tree (MST) mode, but the feature remains disabled (inactive) until you change the spanning-tree mode to PVST+. BackboneFast starts when a root port or ...

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