Enabling Port Fast - Cisco Catalyst 2960 Software Configuration Manual

Configuring Optional Spanning-Tree Features
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Default Optional Spanning-Tree Configuration
Table 18-1
Table 18-1 Default Optional Spanning-Tree Configuration
Feature
Port Fast, BPDU filtering, BPDU guard
UplinkFast
BackboneFast
EtherChannel guard
Root guard
Loop guard
Optional Spanning-Tree Configuration Guidelines
You can configure PortFast, BPDU guard, BPDU filtering, EtherChannel guard, root guard, or loop
guard if your switch is running PVST+, rapid PVST+, or MSTP.
You can configure the UplinkFast, the BackboneFast, or the cross-stack UplinkFast feature for rapid
PVST+ or for the MSTP, but the feature remains disabled (inactive) until you change the spanning-tree
mode to PVST+.

Enabling Port Fast

An interface with the Port Fast feature enabled is moved directly to the spanning-tree forwarding state
without waiting for the standard forward-time delay.
Use Port Fast only when connecting a single end station to an access or trunk port. Enabling this feature
Caution
on an interface connected to a switch or hub could prevent spanning tree from detecting and disabling
loops in your network, which could cause broadcast storms and address-learning problems.
Catalyst 2960 and 2960-S Switches Software Configuration Guide, Release 15.0(1)SE
18-12
Enabling BPDU Guard, page 18-13
Enabling BPDU Filtering, page 18-14
Enabling UplinkFast for Use with Redundant Links, page 18-15
Enabling Cross-Stack UplinkFast, page 18-16
Enabling BackboneFast, page 18-17
Enabling EtherChannel Guard, page 18-17
Enabling Root Guard, page 18-18
Enabling Loop Guard, page 18-18
shows the default optional spanning-tree configuration.
Chapter 18
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Default Setting
Globally disabled (unless they are individually configured
per interface).
Globally disabled. (On Catalyst 2960-S switches, the
UplinkFast feature is the CSUF feature.)
Globally disabled.
Globally enabled.
Disabled on all interfaces.
Disabled on all interfaces.
Configuring Optional Spanning-Tree Features
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