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Configuring Spanning Tree Parameters
Sample MST Region Configuration
OmniSwitch AOS Release 7 Network Configuration Guide
June 2013
page 6-47
Sample MST Region Configuration
An MST region identifies a group of MSTP switches that is seen as a single, flat mode instance by other
regions and/or non-MSTP switches. A region is defined by three attributes: name, revision level, and a
VLAN-to-MSTI mapping. Switches configured with the same value for all three of these attributes belong
to the same MST region.
Note.
An additional configurable MST region parameter defines the maximum number of hops autho-
rized for the region but is not considered when determining regional membership.The maximum hops
value is the value used by all bridges within the region when the bridge is acting as the root of the MST
region.
This section provides a tutorial for defining a sample MST region configuration, as shown in the diagram
below:
In order for switches A, B, and C in the above diagram to belong to the same MST region, they must all
share the same values for region name, revision level, and configuration digest (VLAN-to-MSTI
mapping).
The following steps are performed on each switch to define
Alcatel-Lucent Marketing
as the MST
region name,
2000
as the MST region revision level, map exiting VLANs to existing MSTIs, and
3
as the
maximum hops value for the region:
1
Configure an MST Region name using the
command. For example:
-> spantree mst region name “Alcatel Marketing”
2
Configure the MST Region revision level using the
spantree mst region revision-level
command. For
example:
-> spantree mst region revision-level 2000
MST Region
||
||
Switch C
Switch B
Switch A
Switch E
Switch D
||
SST Switches (STP or RSTP)
CST
IST