190 CHAPTER 13: MSTP CONFIGURATION
Displaying and Debugging MSTP
After completing the above configurations, you can display MSTP operation and
verify your configuration by executing the display command in any view.
You can also clear MSTP-related statistics by executing the reset command in user
view or debug the MSTP module by executing the debugging command in user
view.
MSTP Configuration
Example
Network requirements
Perform MSTP configuration in the network shown in Figure 45 to enable packets of
different VLANs to be forwarded along different spanning tree instances. The detailed
requirements are as follows:
■All switches in the network belong to the same MST region.
■Packets of VLAN 10 are forwarded along spanning tree instance 1; those of VLAN
30 are forwarded along spanning tree instance 3; those of VLAN 40 are forwarded
along spanning tree instance 4; and those of VLAN 20 are forwarded along
spanning tree instance 0.
In this network, Switch A and Switch B operate at the distribution layer, Switch C and
Switch D operate at the access layer. VLAN 10 and VLAN 30 are limited in the
distribution layer and VLAN 40 is limited in the access layer. Switch A and Switch B are
the root bridges of spanning tree instance 1 and spanning tree instance 3 respectively.
Switch C is the root bridge of spanning tree instance 4.
Network diagram
Figure45 Network diagram for MST P configuration
The Permit: shown in Figure 45, means the corresponding link permits packets of
specific VLANs.
Table174 Display and debug MSTP
Operation Command
Display the spanning tree status information
and statistics about the current switch
display stp [ instance instance-id ] [
interface interface-list | slot slot-number ] [
brief ]
Display region configuration display stp region-configuration
Clear MSTP-related statistics reset stp [ interface interface-list ]