spanning-tree mst configuration

Spanning-tree MST (Multiple Spanning Tree) configuration is used to group multiple VLANs into a single spanning tree instance, which reduces the number of STP (Spanning Tree Protocol) instances required on a network.

To configure MST, follow these steps:

1. Enable MST globally on the switch:

`Switch(config)# spanning-tree mode mst`

2. Create the MST region and define the number of MST instances:

`Switch(config)# spanning-tree mst configuration`

3. Configure the MST instance parameters, such as the VLAN-to-instance mapping and the MST region name:

   Switch(config-mst)# instance 1 vlan 10,20
   Switch(config-mst)# instance 2 vlan 30,40
   Switch(config-mst)# name MY-MST-REGION

4. Enable MST on the interfaces that connect to other switches:

`Switch(config-if)# spanning-tree mst 1`

This command enables MST on the interface and assigns it to the specified MST instance.

5. Verify the MST configuration using the following commands:

   Switch# show spanning-tree mst configuration
   Switch# show spanning-tree mst interface
   Switch# show spanning-tree mst vlan

These commands display the MST configuration, the MST instance assignments for each interface, and the VLAN-to-instance mapping.