spanning-tree mst simulate pvst

To reenable specific interfaces to automatically interoperate between Multiple Spanning Tree (MST) and Rapid per VLAN Spanning Tree Plus (Rapid PVST+), use the spanning-tree mst simulate pvst command. To prevent specific MST interfaces from automatically interoperating with a connecting device running Rapid PVST+, use the spanning-tree mst simulate pvst disable command. To return specific interfaces to the default settings that are set globally for the switch, use the no form of this command.

spanning-tree mst simulate pvst

spanning-tree mst simulate pvst disable

no spanning-tree mst simulate pvst

Syntax Description

This command has no arguments or keywords.

Command Default

Enabled. By default, all interfaces on the switch interoperate seamlessly between MST and Rapid PVST+. See the spanning-tree mst simulate pvst global command to change this setting globally.

Command Modes

Interface configuration mode

Command History

Release
Modification
4.0(0)N1(1a)
This command was introduced.

Usage Guidelines

MST interoperates with Rapid PVST+ with no need for user configuration. The PVST+ simulation feature enables this seamless interoperability. However, you may want to control the connection between MST and Rapid PVST+ to protect against accidentally connecting an MST-enabled port to a Rapid PVST+-enabled port.

When you use the spanning-tree mst simulate pvst disable command, specified MST interfaces that receive a Rapid PVST+ (SSTP) bridge protocol data unit (BPDU) move into the STP blocking state. Those interfaces remain in the inconsistent state until the port stops receiving Rapid PVST+ BPDUs, and then the port resumes the normal STP transition process.

Note To block automatic MST and Rapid PVST+ interoperability for the entire switch, use no spanning-tree mst simulate pvst global command.

This command is useful when you want to prevent accidental connection with a device running Rapid PVST+.

To reenable seamless operation between MST and Rapid PVST+ on specific interfaces, use the spanning-tree mst simulate pvst command.

Examples

This example shows how to prevent specified ports from automatically interoperating with a connected device running Rapid PVST+:

switch(config-if)# spanning-tree mst simulate pvst disable
 

Related Commands

Command
Description
spanning-tree mst simulate pvst global
Enables global seamless interoperation between MST and Rapid PVST+.