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MSTP Configuration Example Network requirements
Implement MSTP in the network shown in Figure 1-10 to enable packets of different VLANs to be
forwarded along different spanning tree instances. The detailed configurations are as follows:
z All switches in the network belong to the same MST region.
z Packets of VLAN 10, VLAN 30, VLAN 40, and VLAN 20 are forwarded along spanning tree
instance 1, instance 3, instance 4, and instance 0 respectively.
In this network, Switch A and Switch B operate on the convergence layer; Switch C and Switch D
operate on the access layer. VLAN 10 and VLAN 30 are limited in the convergence layer and VLAN 40
is limited in the access layer. Switch A and Switch B are configured as the root bridges of spanning tree
instance 1 and spanning tree instance 3 respectively. Switch C is configured as the root bridge of
spanning tree instance 4.
Figure 1-10 Network diagram for MSTP configuration
The word “permit” shown in Figure 1-10 means the corresponding link permits packets of specific
VLANs.
Configuration procedure
1) Configure Switch A
# Enter MST region view.
<SwitchA> system-view
[SwitchA] stp region-configuration
# Configure the region name, VLAN-to-MSTI mapping table, and revision level for the MST region.
[SwitchA-mst-region] region-name example
[SwitchA-mst-region] instance 1 vlan 10
[SwitchA-mst-region] instance 3 vlan 30
[SwitchA-mst-region] instance 4 vlan 40
[SwitchA-mst-region] revision-level 0
# Activate the settings of the MST region manually.
[SwitchA-mst-region] active region-configuration
# Specify Switch A as the root bridge of spanning tree instance 1.