Users Guide

Spanning Tree Protocol 859
Configuring Optional STP Features
Use the following commands to configure the optional STP features on the
switch or on specific interfaces.
show spanning-tree
[detail [active |
blockedports | instance
instance-id ]]
View information about spanning tree and the spanning
tree configuration on the switch.
Command Purpose
configure Enter global configuration mode.
spanning-tree bpdu
flooding
Allow the flooding of BPDUs received on non-spanning-
tree ports to all other non-spanning-tree ports.
spanning-tree portfast
default
Enable PortFast on all switch ports.
spanning-tree portfast
bpdufilter default
Prevent ports configured in PortFast mode from sending
BPDUs.
spanning-tree loopguard
default
Enable loop guard on all ports.
spanning-tree bpdu-
protection
Enable BPDU protection on the switch.
interface interface Enter interface configuration mode for the specified
interface. The interface variable includes the interface type
and number, for example tengigabitethernet 1/0/3 or port-
channel 4.
A range of interfaces can be specified using the interface
range command. For example, interface range
tengigabitethernet 1/0/8-12 configures interfaces 8, 9, 10,
11, and 12. The range keyword is also valid for LAGs (port-
channels).
spanning-tree auto-
portfast
Set the port to auto portfast mode. This enables the port
to become a portfast port if it does not see any BPDUs for
3 seconds.
Command Purpose