Function Description
The multiple spanning tree protocol (MSTP) applies to the redundant network.
MSTP is an improvement of STP and RSTP.
MSTP prevents the proliferation and
infinite cycling of the packets in the loop network. In addition, MSTP provides
multiple redundant paths for VLAN data transmission to achieve the load-sharing
purpose. The
MA5600T/MA5603T/MA5608T supports MSTP,
which is compatible with the STP and RSTP. It supports MSTP loop network that
helps meet various networking requirements.
Function
The vlan-mapping module command is used to map all VLANs to
the spanning tree instances by modulo. When you need to map VLAN to each
spanning tree instance rapidly, run this command. After all VLANs map to the
matched spanning tree instance by module algorithm, each VLAN belongs to
different spanning tress instance based on the user configuration.
The undo vlan-mapping module command is used to remap all
VLANs to common and internal spanning (CIST) instance. When you need to restore
the mapping relationship, run this command. After all VLANs are remapped to CIST
instance, each VLAN is mapped to CIST instance.
Parameters
Parameter |
Description |
Value |
module |
Indicates the module value, that is the number of MSTP instances. When you
need to specify the mapping relationship between VLAN and spanning tree
instance, use this parameter. |
Numeral type. Range: 0-16.
|
Usage Guidelines
- Run the config command to enter
global config mode, and then run the stp region-configuration
command to enter MST area mode.
- By default, all VLANs map CIST instance, that is, instance 0.
- The command is used to map VLAN to each spanning tree instance rapidly. The
ID of the mapped instance is (VLAN ID-1)% module+1.
- (VLAN ID-1)% module is the modular algorithm for (VLAN ID-1). When you
calculate the modular value by 16, VLAN 1 maps to MSTI 1, VLAN 2 maps to MSTI 2.
... VLAN 16 maps to MSTI 16 and VLAN 17 maps to MSTI 1. The rest may be reduced
by analogy.
- Running the command can cause the mapping relationship of all VLANs change.
In actual application, you can run this command first, and then run the
instance vlan command to
adjust the mappings slightly as required.
- The configuration can be used after it is activated.
- Two devices that belong to a same MST region meet the following
requirements:
- The area names are the same.
- The area levels are the same.
- The configuration digest are the same. The configuration digest is
calculated by VLAN mapping table of all the spanning trees and MD5-KEY through
MD5 ciphering algorithm.
Example
To map all VLANs to spanning tree instance, with the modular value of 1, do
as follows:
huawei(stp-region-configuration)#vlan-mapping module
{ INTERGER<0-16> }:1
Command:
vlan-mapping module 1
To remap all VLANs to CIST instance, do as follows:
huawei(stp-region-configuration)#undo vlan-mapping module
System Response
- The system does not display any message after the
command is executed successfully.