3Com Switch 4200G Configuration Guide

120 CHAPTER 20: MSTP CONFIGURATION
MST Region
Configuration
Configuration procedure
Configuring MST region-related parameters (especially the VLAN mapping table)
results in spanning trees being regenerated. To reduce network topology jitter caused
by the configuration, MSTP does not regenerate spanning trees immediately after the
configuration; it does this only after you perform one of the following operations,
and then the configuration can really takes effect:
■ Activating the new MST region-related settings by using the active
region-configuration command
■ Enabling MSTP by using the stp enable command
Switches belong to the same MST region only when they have the same MST region
name, VLAN mapping table, and MSTP revision level.
Configuration example
1 Configure an MST region, with the name being “info”, the MSTP revision level being
level 1, VLAN 2 through VLAN 10 being mapped to spanning tree instance 1, and
VLAN 20 through VLAN 30 being mapped to spanning tree 2.
<S4200G> system-view
System View: return to User View with Ctrl+Z.
[4200G] stp region-configuration
[4200G-mst-region] region-name info
[4200G-mst-region] instance 1 vlan 2 to 10
[4200G-mst-region] instance 2 vlan 20 to 30
[4200G-mst-region] revision-level 1
[4200G-mst-region] active region-configuration
2 Verify the above configuration.
[4200G-mst-region] check region-configuration
Table 85 Configure an MST region
Operation Command Description
Enter system view system-view —
Enter MST region view stp region-configuration —
Configure a name for
the MST region
region-name name Required
The default MST region name of a
switch is its MAC address.
Configure the VALN
mapping table for the
MST region
instance instance-id vlan vlan-list Required
Both commands can be used to
configure VLAN mapping tables.
By default, all VLANs in an MST
region are mapped to spanning tree
instance 0.
vlan-mapping modulo modulo
Configure the MSTP
revision level for the
MST region
revision-level level Required
The default revision level of an MST
region is level 0.
Activate the
configuration of the
MST region manually
active region-configuration Required
Display the
configuration of the
current MST region
check region-configuration Optional
Display the currently
valid configuration of
the MST region
Display stp region-configuration You can execute this command in
any view.