Leaflet

OL-11615-01

is not supported on non-Cisco devices. Rapid-Per-VLAN-Spanning Tree (Rapid-PVST+) is another

version of PVST that provides faster convergence of the spanning tree by using Rapid Spanning Tree

Protocol (RSTP) with the existing configuration for PVST+.

PVST+ and Rapid-PVST+ are available on Catalyst 6500 and 4500 Series switches for both Catalyst OS

and Cisco IOS. The default spanning tree protocol for Catalyst 6500 Series switches is Rapid-PVST+

for systems running Catalyst OS software, and PVST+ for systems running Cisco IOS software. PVST+

is the default spanning tree for Catalyst 4500 Series switches for both, Catalyst OS and Cisco IOS

software.

To modify the spanning tree mode on a system running Catalyst OS, use the set spantree mode

command.

Console> (enable) set spantree mode {mistp | pvst+ | mistp-pvst+ | mst | rapid-pvst+}

This example shows how to configure Rapid-PVST+:

Console> (enable) set spantree mode rapid-pvst+

Warning!! Changing the STP mode from a telnet session will disconnect the

session because there are no VLANs mapped to any RAPID-VST+ instance.

Do you want to continue [n]?

For more information on the set spantree mode command on the Catalyst 6500, refer to the following

URL:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/sw_8_5/cmd_ref/setsn

_su.htm#wp1058609

For more information on the set spantree mode command on the Catalyst 4500, refer to the following

URL:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat4000/8_3/command/set_q_s.htm#wp1085096

To modify the spanning tree mode on a system running Cisco IOS, use the spanning-tree mode

command:

Switch(config)# spanning-tree mode [pvst | mst | rapid-pvst]

This example shows how to configure Rapid-PVST+:

Switch(config)# spanning-tree mode rapid-pvst

Switch(config)#

For more information on the spanning-tree mode command on the Catalyst 6500, refer to the following

URL:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat6000/122sx/cmdref/s1.htm#wp1087162

For more information on the spanning-tree mode command on the Catalyst 4500, refer to the following

URL:

http://www.cisco.com/univercd/cc/td/doc/product/lan/cat4000/12_2_31s/cmdref/snmp

_vtp.htm#wp1144173

BPDU Guard

BPDU guard is an available feature on Catalyst 6500 and 4500 Series switches running Catalyst OS and

Cisco IOS software that prevents a host port from participating in spanning tree. Under normal

circumstances, Layer 2 access ports connected to a single workstation or server should not participate in