1-39Configuration PrerequisitesMSTP runs normally on the switch.Configuration procedureFollow these steps to configure BPDU dropping:To do... Use the command... RemarksEnter system view system-view —Enter Ethernet port view interface interface-name —Enable BPDU dropping bpdu-drop any RequiredBPDU dropping is disabled by default.Configuration example# Enable BPDU dropping on GigabitEthernet 1/0/1.system-view[Sysname] interface GigabitEthernet 1/0/1[Sysname-GigabitEthernet1/0/1] bpdu-drop anyConfiguring Digest SnoopingIntroductionAccording to IEEE 802.1s, two interconnected switches can communicate with each other throughMSTIs in an MST region only when the two switches have the same MST region-related configuration.Interconnected MSTP-enabled switches determine whether or not they are in the same MST region bychecking the configuration IDs of the BPDUs between them (A configuration ID contains informationsuch as region ID and configuration digest).As some other manufacturers' switches adopt proprietary spanning tree protocols, they cannotcommunicate with the other switches in an MST region even if they are configured with the same MSTregion-related settings as the other switches in the MST region.This problem can be overcome by implementing the digest snooping feature. If a port on an S5100Ethernet switch is connected to another manufacturer's switch that has the same MST region-relatedconfiguration as its own but adopts a proprietary spanning tree protocol, you can enable digestsnooping on the port. Then the S5100 Ethernet switch regards another manufacturer's switch as in thesame region; it records the configuration digests carried in the BPDUs received from anothermanufacturer's switch, and put them in the BPDUs to be sent to the another manufacturer's switch. Inthis way, the S5100 Ethernet switch can communicate with another manufacturer’s switches in thesame MST region.The digest snooping function is not applicable to edge ports.
