Setup Guide

spanning-tree MSTi vlan 2 300
(Step 2)
interface 1/0/31
no shutdown
spanning-tree port mode enable
switchport protected 0
exit
interface 1/0/32
no shutdown
spanning-tree port mode enable
switchport protected 0
exit
(Step 3)
interface vlan 100
tagged 1/0/31
tagged 1/0/32
exit
interface vlan 200
tagged 1/0/31
tagged 1/0/32
exit
interface vlan 300
tagged 1/0/31
tagged 1/0/32
exit
Debugging and Verifying MSTP Congurations
To debut and verify MSTP conguration, use the following commands.
• Display BPDUs.
EXEC Privilege mode
debug spanning-tree mstp bpdu
• Display MSTP-triggered topology change messages.
debug spanning-tree mstp events
Examples of Viewing MSTP Information
To ensure all the necessary parameters match (region name, region version, and VLAN to instance mapping), examine your individual
routers.
To show various portions of the MSTP conguration, use the show spanning-tree mst commands.
To view the overall MSTP conguration on the router, use the show running-configuration spanning-tree mstp in EXEC
Privilege mode.
To monitor and verify that the MSTP conguration is connected and communicating as desired, use the debug spanning-tree mstp
bpdu command.
Key items to look for in the debug report include:
• MSTP ags indicate communication received from the same region.
– As shown in the following, the MSTP routers are located in the same region.
– Does the debug log indicate that packets are coming from a “Dierent Region”? If so, one of the key parameters is not matching.
• MSTP Region Name and Revision.
– The congured name and revisions must be identical among all the routers.
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Multiple Spanning Tree Protocol (MSTP)