The MSTP Configuration of vlan-mapping module

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 MA5680T/MA5683T/MA5608T supports MSTP, which is compatible with the STP and RSTP. It supports MSTP loop network that helps meet various networking

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.

Format

vlan-mapping module module
undo vlan-mapping module

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.

Modes

MST area mode, OSN 3500, OSN 7500

Level

Operator level

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.
• For more information about the error message that the system displays against a command entered with incorrect syntax, see the "Syntax Check" in Parameter.