第十六章-Trunk和VTP

©2006,ShenzhenPolytechnic,Allrightsreserved.1TrunkandVTP©2006,ShenzhenPolytechnic.Allrightsreserved.2教学目标（Objectives）1.Trunk概念（TrunkingConcepts）2.Trunk操作（TrunkingOperation）3.VTP模式（VTPModes）4.VTP怎样工作（HowVTPWorks）5.配置VTP（ConfiguringandVerifyingVTP）6.配置和验证Trunk（ConfiguringandVerifyingTrunk）©2006,ShenzhenPolytechnic.Allrightsreserved.3Trunk的历史（HistoryofTrunking）©2006,ShenzhenPolytechnic.Allrightsreserved.4Trunk概念（TrunkingConcepts）©2006,ShenzhenPolytechnic.Allrightsreserved.5Trunk概念（TrunkingConcepts）1.Trunk是两个交换机之间网络信息传递的物理和逻辑的连接Atrunkisaphysicalandlogicalconnectionbetweentwoswitchesacrosswhichnetworktraffictravels.2.一个Trunk就是支持传递多个VLAN信息的点到点的链路Atrunkisapoint-to-pointlinkthatsupportsseveralVLANs.3.Trunk的目的是保留端口。Thepurposeofatrunkistoconserveports.4.Trunk将在一个物理链路上绑定多个虚链路，从而在两台交换机之间允许在单一物理链路上传输多个VLAN的信息TrunkingwillbundlemultiplevirtuallinksoveronephysicallinkbyallowingthetrafficforseveralVLANstotraveloverasinglecablebetweentheswitches.©2006,ShenzhenPolytechnic.Allrightsreserved.6Trunk操作（TrunkingOperation）1.Trunk机制有两种，帧过滤和帧标记，帧标记被IEEE标准化Currentlytwotypesoftrunkingmechanismsexist,framefilteringandframetagging.FrametagginghasbeenadoptedasthestandardtrunkingmechanismbyIEEE.2.帧标记在帧中插入标识符，这样可以更容易管理Trunkingprotocolsthatuseaframetaggingmechanismassignanidentifiertotheframestomaketheirmanagementeasier.3.在以太网中，帧标记有两种方案TaggingschemesforEthernetsegments:ISL–Cisco私有（CiscoproprietaryInter-SwitchLinkprotocol）802.1Q–IEEE标准（IEEEstandard）©2006,ShenzhenPolytechnic.Allrightsreserved.7VLANsandTrunkingTrunk提供了在一个网络内的交换机之间高效的通信©2006,ShenzhenPolytechnic.Allrightsreserved.8VLANTrunk协议（VLANTrunkingProtocol）•1.VTP是一个通告VLAN信息的信息系统•AmessagingsystemthatadvertisesVLANconfigurationinformation•2.VTP维护整个管理域VLAN信息的一致性•MaintainsVLANconfigurationconsistencythroughoutacommonadministrativedomain•3.VTP仅在Trunk端口上发送通告•VTPsendsadvertisementsontrunkportsonly1.有新VLAN加入（“newvlanadded”）3.同步到最新的VLAN信息（Synctothelatestvlaninformation）2VTPDomain“szpt”©2006,ShenzhenPolytechnic.Allrightsreserved.9VTP模式（VTPModes）Transparent•转发通告（Forwardsadvertisements）•同步（Synchronize）•不包存（NotsavedinNVRAM）•创建（Createvlans）•修改（Modifyvlans）•删除（Deletevlans）•发送或转发通告（Sends/forwardsadvertisements）•同步（Synchronize）•保存（SavedinNVRAM）创建（Createvlans）修改（Modifyvlans）删除（Deletevlans）转发通告（forwardsadvertisements）不同步（doesnotSynchronize）保存（SavedinNVRAM）©2006,ShenzhenPolytechnic.Allrightsreserved.10VTP怎样工作（HowVTPWorks）•VTP通告以组播帧发送•VTPadvertisementsaresentasmulticastframes•VTPserver和client同步到最新的配置版本号•VTPserversandclientssynchronizedtolatestrevisionnumber•VTP通告在变化时，或者每5分钟发送•VTPadvertisementaresenteveryfiveminutesorwhenthereisachange©2006,ShenzhenPolytechnic.Allrightsreserved.11VTP怎样工作（HowVTPWorks）1.AddnewVLAN2.Rev3--Rev4ServerClientClient4.Rev3--Rev45.Syncnewvlaninfo334.Rev3--Rev45.Syncnewvlaninfo•VTP通告以组播帧发送•VTPadvertisementsaresentasmulticastframes•VTPserver和client同步到最新的配置版本号•VTPserversandclientssynchronizedtolatestrevisionnumber•VTP通告在变化时，或者每5分钟发送•VTPadvertisementaresenteveryfiveminutesorwhenthereisachange©2006,ShenzhenPolytechnic.Allrightsreserved.12•配置Trunk接口•（Enabletrunking）•配置VTP域名•（VTPdomainname）•指定VTP模式•（VTPmode(server/client/transparent)—VTPservermodeisthedefault）•VTP密码（VTPpassword）配置VTP（VTPConfiguration）©2006,ShenzhenPolytechnic.Allrightsreserved.13创建VTP域（CreatingaVTPDomain）sw1#vlandatabasesw1(vlan)#vtpdomainciscoVTPdomainciscomodifiedsw1(vlan)#vtpserversw1(vlan)#vtppasswordciscosw1(vlan)#exitAPPLYcompleted.©2006,ShenzhenPolytechnic.Allrightsreserved.14验证VTP配置（VerifyingVTPConfigurations）Sw1#showvtpstatus©2006,ShenzhenPolytechnic.Allrightsreserved.15定义Trunk（DefiningaTrunk）sw2(config)#intf0/12sw2(config-if)#switchportmodetrunksw2(config-if)#switchporttrunkencapsulationdot1q©2006,ShenzhenPolytechnic.Allrightsreserved.16验证Trunk（VerifyingaTrunk）sw2#showinterfacestrunkPortModeEncapsulationStatusNativevlanFa0/12on802.1qtrunking1PortVlansallowedontrunkFa0/121-4094PortVlansallowedandactiveinmanagementdomainFa0/122,3PortVlansinspanningtreeforwardingstateandnotprunedFa0/122,3©2006,ShenzhenPolytechnic.Allrightsreserved.17思考题（Questions）1.Trunk有怎样的特征？2.使用Trunk有什么好处？3.Trunk有哪两种机制？4.帧标记有哪两种方案？5.什么是VTP？6.VTP有几种模式？每种模式的特征是什么？7.VTP是怎样工作的?