ccnp 11 1introducing spanning tree features以伙伴关系帮助客户成功员工合作伙伴

IntroducingSTPDescribingConfiguringspanning-treeportfast(interfacecommand)spanning-treeportfastdefault(global–enablesPortFastonallnontrunkingshowrunning-configinterfacefastethernetBackboneFast 的RootPort和原本处于Blocking状态的端口都收到BPDU了。 BackboneFast[no]spanning-treebackbonefast(globalShowspanning-treeEnablingandVerifyingBPDU防⽌在配置了PortFast的端⼝上收到BPDU，如果配置了PortFast⼝收到BPDU，则使该端⼝进入err-disableSwitch(config)#spanning-treeportfastbpduguardSwitch(config)#spanning-treeportfastbpduguardSwitch#showSwitch#showspanning-treesummary ysBPDUGuardconfigurationSwitch#showspanning-treesummarytotalsRootbridgefor:none.PortFastBPDUGuardisEtherchannelmisconfigurationguardisenabledUplinkFastisdisabledBackboneFastisDefaultpathcostmethodusedis BlockingListeningLearningForwardingSTP34 EnablingandVerifyingBPDUEnableBPDUSwitch(config)#spanning-treeEnableBPDUSwitch(config)#spanning-treeportfastbpdufilterSwitch#showspanning-treesummaryDispalysBPDUSwitch#showspanning-treesummarySwitch#showspanning-treesummaryRootRootbridgeEtherChannelmisconfigurationguardisenabledExtendedsystemID isdisabled isenabledbydefaultPortFastBPDUGuardisdisabledbydefaultPortfastBPDUFilterisenabledbydefault isdisabledbydefault is isdisabledPathcostmethodusedislongBlockingListeningLearningForwardingSTP200033 EnablingRootSwitch(config-if)#spanning-treeSwitch(config-if)#spanning-treeguardEnablesRootGuardonanVerifyingRootSwitch#showSwitch#showrunning-configinterfaceinterface ysinterfaceconfigurationSwitch#showSwitch#showspanning-tree ysinformationaboutportsininconsistentSwitch#showrunning-configinterfacefastethernet5/8Buildingconfiguration...Currentconfiguration:67!switchportmodeaccessspanning-treeguardroot

PortTypeInconsistentPortTypeInconsistentPortTypeInconsistentNumberofinconsistentports(segments)inthesystemBeforeLoopBeforeLoopGuardWithLoop*使用了LoopGuard后，就会使端口进入“不一致环路”状态 ConfiguringLoopSwitch(config-if)#spanning-treeSwitch(config-if)#spanning-treeguardEnablesLoopGuardonanSwitch(config)#spanning-treeSwitch(config)#spanning-treeloopguardEnablesloopguardgloballyontheUnidirectionalLinkUDLDallowsdevicesconnectedUDLDallowsdevicesconnectedthroughfiber-opticorcopperEthernetcablestomonitorthephysicalconfigurationofthecablesanddetectwhenaunidirectionallinkexists.Unidirectionallinkscancauseavarietyofproblems,includingspanning-treetopologyloops.ConfiguringConfigurationconfigudldenable(allportnormaludldaggressive(allportaggressiveconfiginterfaceportudldport(portnormaludldportaggressive(portaggressiveResettingandVerifyingComparingLoopGuardandPotentialSTP双工不匹配：当一个链路的一端是半双工的，而另一端是全双工。这 单向链路故障:资源错误:STP是在软件中实现,当交换机过载使用CPU和内存时，造PortFast配置错误:连接交换机的两个端口启用快速端口，这可能会STP调整误差:Maxageforwarddelay设置太短会导致一个环路。DuplexUnidirectionalLinkPortFastConfigurationSpanningTreedebugSwitch#debugSwitch#debugspanning-tree ysalldebuggingmessagesforspanningSwitch#debugSwitch#debugspanning-tree ysspanning-treetopologyeventsdebugSw