1-41To do... Use the command... RemarksDisplay the currentconfiguration display current-configuration Available in any viewz When the digest snooping feature is enabled on a port, the port state turns to the discarding state.That is, the port will not send BPDU packets. The port is not involved in the STP calculation until itreceives BPDU packets from the peer port.z The digest snooping feature is needed only when your switch is connected to anothermanufacturer’s switches adopting proprietary spanning tree protocols.z To enable the digest snooping feature successfully, you must first enable it on all the ports of yourswitch that are connected to another manufacturer’s switches adopting proprietary spanning treeprotocols and then enable it globally.z To enable the digest snooping feature, the interconnected switches and another manufacturer’sswitch adopting proprietary spanning tree protocols must be configured with exactly the same MSTregion-related configurations (including region name, revision level, and VLAN-to-MSTI mapping).z The digest snooping feature must be enabled on all the switch ports that connect to anothermanufacturer’s switches adopting proprietary spanning tree protocols in the same MST region.z When the digest snooping feature is enabled globally, the VLAN-to-MSTI mapping table cannot bemodified.z The digest snooping feature is not applicable to boundary ports in an MST region.z The digest snooping feature is not applicable to edge ports in an MST region.Configuring Rapid TransitionIntroductionDesignated ports of RSTP-enabled or MSTP-enabled switches use the following two types of packets toimplement rapid transition:z Proposal packets: Packets sent by designated ports to request rapid transitionz Agreement packets: Packets used to acknowledge rapid transition requestsBoth RSTP and MSTP specify that the upstream switch can perform rapid transition operation on thedesignated port only when the port receives an agreement packet from the downstream switch. Thedifference between RSTP and MSTP are:z For MSTP, the upstream switch sends agreement packets to the downstream switch; and thedownstream switch sends agreement packets to the upstream switch only after it receivesagreement packets from the upstream switch.z For RSTP, the upstream switch does not send agreement packets to the downstream switch.Figure 1-6 and Figure 1-7 illustrate the rapid transition mechanisms on designated ports in RSTP andMSTP.
