180 CHAPTER 14: MSTP CONFIGURATIONmanufacturer’s switch running proprietary spanning tree protocols, you can enablethe rapid transition feature on the ports of the 3Com series switch operating asthe downstream switch. Among these ports, those operating as the root ports willthen send agreement packets to their upstream ports after they receive proposalpackets from the upstream designated ports, instead of waiting for agreementpackets from the upstream switch. This enables designated ports of the upstreamswitch to change their states rapidly.Configuring RapidTransitionConfiguration prerequisitesAs shown in Figure 53, a 3Com series switch is connected to anothermanufacturer’s switch. The former operates as the downstream switch, and thelatter operates as the upstream switch. The network operates normally.The upstream switch is running a proprietary spanning tree protocol that is similarto RSTP in the way to implement rapid transition on designated ports. Port 1 is thedesignated port.The downstream switch is running MSTP. Port 2 is the root port.Figure 53 Network diagram for rapid transition configurationConfiguration procedure1 Configure the rapid transition feature in system view2 Configure the rapid transition feature in Ethernet port viewTable 136 Configure the rapid transition feature in system viewOperation Command DescriptionEnter system view system-view -Enable the rapid transitionfeaturestp interface interface-typeinterface-numberno-agreement-checkRequiredBy default, the rapid transitionfeature is disabled on a port.Table 137 Configure the rapid transition feature in Ethernet port viewOperation Command DescriptionEnter system view system-view -
