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Catalyst 4500 Series, Catalyst 2948G, Catalyst 2948G-GE-TX, and Catalyst 2980G Switches Software Configuration Guide—Release 8.2GLX
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Chapter 8 Configuring Spanning Tree PortFast, BPDU Guard, BPDU Filter, UplinkFast, BackboneFast, and Loop Guard
Configuring PortFast BPDU Guard
Resetting PortFast
To reset PortFast on a switch or trunk port to its default settings, perform this task in privileged mode:
This example shows how to reset PortFast to its default settings on port 1 of module 4:
Console> (enable) set spantree portfast 4/1 default
Spantree port 4/1 fast start set to default.
Console> (enable) show spantree portfast 4/1
Portfast:default
Portfast BPDU guard is disabled.
Portfast BPDU filter is disabled.
Console> (enable)
Configuring PortFast BPDU Guard
The following sections describe how to configure PortFast BPDU guard on the switch.
Enabling PortFast BPDU Guard
The PortFast feature is configured on an individual port, and the PortFast BPDU guard option is
configured either globally or on a per-port basis.
When you disable PortFast on a port, PortFast BPDU guard becomes inactive. The port configuration
overrides the global configuration unless the port configuration is set to default. If the port configuration
is set to default, the global configuration is checked. If the port configuration is enabled, the port
configuration is used and the global configuration is not used.
To enable and verify PortFast BPDU guard on a nontrunking switch port, perform this task in privileged
mode:
Note For additional PVST+ information, see Chapter 7, “Configuring Spanning Tree.”
Task Command
Step 1
Reset PortFast to its default settings on a switch
port.
set spantree portfast mod_num/port_num
default
Step 2
Verify the PortFast setting. show spantree mod_num/port_num
Task Command
Step 1
Enable BPDU guard on an individual port. set spantree portfast bpdu-guard mod/port [disable |
enable | default]
Step 2
Verify the PortFast BPDU guard setting. show spantree summary