3Com Switch 7750 Configuration Guide Guide

230 CHAPTER 29: MSTP CONFIGURATION
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
n
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
# 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.
<SW7750> system-view
[SW7750] stp region-configuration
[SW7750-mst-region] region-name info
[SW7750-mst-region] instance 1 vlan 2 to 10
[SW7750-mst-region] instance 2 vlan 20 to 30
[SW7750-mst-region] revision-level 1
[SW7750-mst-region] active region-configuration
# Verify the above configuration.
[SW7750-mst-region] check region-configuration
Admin configuration
Format selector :0
Region name :info
Revision level :1
Instance Vlans Mapped
0 11 to 19, 31 to 4094
1 1 to 10
2 20 to 30
Root Bridge/Secondary
Root Bridge
Configuration
MSTP can automatically choose a switch as a root bridge. You can also manually
specify the current switch as a root bridge by using the corresponding commands.
Root bridge configuration
Display the currently valid
configuration of the MST
region
Display stp
region-configuration
You can execute this
command in any view.
Table 155 Configure an MST region
Operation Command Description
Tabl e 156 Specify the current switch as the root bridge of a specified spanning tree
Operation Command Description
Enter system view system-view -