Spanning-Tree Mode - Cisco ME 3400 Command Reference Manual

Ethernet access switch

Hide thumbs Also See for ME 3400:

Table of Contents

spanning-tree mode

Use the spanning-tree mode global configuration command to enable per-VLAN spanning-tree plus

(PVST+), rapid PVST+, or multiple spanning tree (MST) on your switch. Use the no form of this

command to return to the default setting.

Syntax Description

The default mode is rapid PVST+.

Command Modes

Global configuration

Command History

Usage Guidelines

Spanning Tree Protocol (STP) is supported on the switch only on network node interfaces (NNIs) or on

enhanced network interfaces (ENIs) on which STP has been enabled. To set a port as an NNI or ENI,

enter the port-type {eni | nni} interface configuration command. To enable STP on an ENI, enter the

spanning-tree interface configuration command.

STP is not supported on user network interfaces (UNIs).

The switch supports PVST+, rapid PVST+, and MSTP, but only one version can be active at any time:

All VLANs run PVST+, all VLANs run rapid PVST+, or all VLANs run MSTP.

When you enable the MST mode, RSTP is automatically enabled.

Changing spanning-tree modes can disrupt traffic because all spanning-tree instances are stopped for the

previous mode and restarted in the new mode.

This example shows to enable MST and RSTP on the switch:

Switch(config)# spanning-tree mode mst

This example shows to enable PVST+ on the switch:

Switch(config)# spanning-tree mode pvst

Cisco ME 3400 Ethernet Access Switch Command Reference

spanning-tree mode {mst | pvst | rapid-pvst}

no spanning-tree mode

Enable MST and Rapid Spanning Tree Protocol (RSTP) (based on IEEE 802.1s and

IEEE 802.1w).

Enable PVST+ (based on IEEE 802.1D).

Enable rapid PVST+ (based on IEEE 802.1w).

Modification

This command was introduced.

Chapter 2 Cisco ME 3400 Ethernet Access Switch Cisco IOS Commands