Connectivity Guide

Table Of Contents
MSTP configuration
When you enable Multiple Spanning Tree Protocol (MSTP) on VLT nodes, configure both VLT peer nodes in the same MST
region to avoid network loops. Ensure that the VLAN-to-instance mappings, region name, and revision ID are same on both VLT
peer nodes.
To configure MSTP over VLT, follow these steps on both VLT peer nodes:
1. Enable MSTP.
CONFIGURATION mode
spanning-tree mode mst
2. Enter MST configuration mode.
CONFIGURATION mode
spanning tree mst configuration
3. Create an MST instance and add multiple VLANs as required.
MULTIPLE-SPANNING-TREE
instance instance-number vlan from-vlan-id to-vlan-id
4. Configure the MST revision number, from 0 to 65535.
MULTIPLE-SPANNING-TREE
revision revision-number
5. Configure the MST region name.
MULTIPLE-SPANNING-TREE
name name-string
The following example shows that both VLT nodes are configured with the same MST VLAN-to-instance mapping..
VLT Peer 1 confoguration
OS10(config)# spanning-tree mode mst
OS10(config)# spanning-tree mst configuration
OS10(conf-mst)# instance 1 vlan 2-10
VLT Peer 2 confoguration
OS10(config)# spanning-tree mode mst
OS10(config)# spanning-tree mst configuration
OS10(conf-mst)# instance 1 vlan 2-10
The following example shows MSTP information on VLT:
OS10# show spanning-tree virtual-interface
VFP(VirtualFabricPort) of MSTI 0 is Designated Forwarding
Edge port: No (default)
Link type: point-to-point (auto)
Boundary: Yes, Bpdu-filter: Disable, Bpdu-Guard: Disable, Shutdown-on-Bpdu-Guard-violation: No
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Virtual Link Trunking