20-17
Configuring Root Bridge
Configuring an MST Region
Configuration procedure
Follow these steps to configure an MST region:
To do...
Use the command...
Remarks
Enter system view
system-view
—
Enter MST region view
stp region-configuration
—
Configure the name of the MST
region
region-name name
Required
The default MST region name of a
switch is its MAC address.
instance
instance-id
vlan
vlan-list
Configure the VLAN-to-instance
mapping table for the MST region
vlan-mapping modulo
modulo
Required
Both commands can be used to
configure VLAN-to-instance
mapping tables.
By default, all VLANs in an MST
region are mapped to MSTI 0.
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
Available in any view
Neighbor Topology Discovery Protocol (NTDP) packets sent by devices in a cluster can only be
transmitted within the MSTI where the management VLAN of the cluster resides. For more information
about clusters and the NTDP protocol, see
Cluster Operation
.
Configuring MST region-related parameters (especially the VLAN-to-instance mapping table) results in
spanning tree recalculation and network topology jitter. To reduce network topology jitter caused by the
configuration, MSTP does not recalculate 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:
z
Activate the new MST region-related settings by using the
active region-configuration
command
z
Enable MSTP by using the
stp enable
command