Command Manual – MSTPH3C S3100-52P Ethernet Switches Chapter 1 MSTP Configuration Commands1-50 system-viewSystem View: return to User View with Ctrl+Z.[H3C] interface Ethernet1/0/1[H3C-Ethernet1/0/1] stp transmit-limit 151.1.47 vlan-mapping moduloSyntaxvlan-mapping modulo moduloViewMST region viewParametermodulo: Modulo ranging from 1 to 16.DescriptionUse the vlan-mapping modulo command to map the specified VLAN list to thespecific spanning tree instance.By default, all VLANs in a network are mapped to the CIST (spanning tree instance 0).MSTP uses a VLAN mapping table to describe VLAN-to-MSTI mappings. You can usethis command to establish the VLAN mapping table and to map VLANs to the specificspanning tree instances.Note that a VLAN cannot be mapped to multiple different spanning tree instances at thesame time. A VLAN-to-MSTI mapping becomes invalid when you map the VLAN toanother spanning tree instance.Note:You can map VLANs to the specific spanning tree instances rapidly by using thevlan-mapping modulo modulo command. The ID of the spanning tree instance towhich a VLAN is mapped can be figured out by using the following formula:(VLAN ID-1) % modulo + 1.In this formula, (VLAN ID-1) % modulo yields the module of (VLAN ID-1) with regards tothe modulo argument. For example, if you set the modulo argument to 16, then VLAN 1is mapped to spanning tree instance 1, VLAN 2 is mapped to spanning tree instance2, …, VLAN 16 is mapped to spanning tree instance 16, VLAN 17 is mapped tospanning tree instance 1, and so on.
