cisco-VLAN-PPT参考

©2000,CiscoSystems,Inc.7-1Chapter7ExtendingSwitchedNetworkswithVirtualLANs©2000,CiscoSystems,Inc.—7-2ObjectivesUponcompletionofthischapter,youwillbeabletoperformthefollowingtasks:•ConfigureaVLAN•ConfigureVLANTrunkingProtocol(VTP)•Configureaswitchfortrunking•VerifyVLANconnectivity•Verifyspanning-treeoperations©2000,CiscoSystems,Inc.—7-3VLANOverview•Segmentation•Flexibility•Security3rdfloor2ndfloor1stfloorSALESHRENGAVLAN=Abroadcastdomain=Logicalnetwork(subnet)©2000,CiscoSystems,Inc.—7-4VLANOperationsSwitchAGreenVLANBlackVLANRedVLAN•EachlogicalVLANislikeaseparatephysicalbridge©2000,CiscoSystems,Inc.—7-5VLANOperationsSwitchAGreenVLANBlackVLANRedVLANSwitchBGreenVLANBlackVLANRedVLAN•EachlogicalVLANislikeaseparatephysicalbridge•VLANscanspanacrossmultipleswitches©2000,CiscoSystems,Inc.—7-6VLANOperationsSwitchAGreenVLANBlackVLANRedVLANSwitchBGreenVLANBlackVLANRedVLANTrunk•EachlogicalVLANislikeaseparatephysicalbridge•VLANscanspanacrossmultipleswitches•TrunkscarriestrafficformultipleVLANs•TrunksusespecialencapsulationtodistinguishbetweendifferentVLANsFastEthernet©2000,CiscoSystems,Inc.—7-7VLANMembershipModesVLAN5StaticVLANDynamicVLANMAC=1111.1111.1111TrunkVMPS1111.1111.1111=vlan10VLAN10Porte0/9Porte0/4©2000,CiscoSystems,Inc.—7-8ISLTagging•PerformedwithASIC•Notintrusivetoclientstations,clientdoesnotseetheISLheader•Effectivebetweenswitches,routersandswitches,switchesandserverswithISLnetworkinterfacecardsISLtrunksenableVLANsacrossabackboneVLANTagaddedbyincomingportVLANTagstrippedbyforwardingportInter-SwitchLinkcarriesVLANidentifier©2000,CiscoSystems,Inc.—7-9ISLEncapsulationISLHeader26bytesEncapsulatedEthernetframeCRC4bytes•FramesencapsulatedwithISLheaderandCRC•SupportformanyVLANs(1024)•VLANfield•BPDUbitDATypeUserSALENVLANAAAA03BPDUHSAVLANBPDUBPDUINDEXRES©2000,CiscoSystems,Inc.—7-10VLANTrunkingProtocol(VTP)•AmessagingsystemthatadvertisesVLANconfigurationinformation•MaintainsVLANconfigurationconsistencythroughoutacommonadministrativedomain•VTPsendsadvertisementsontrunkportsonly•Supportmixedmediatrunks(FastEthernet,FDDI,ATM)1.“newvlanadded”3.Synctothelatestvlaninformation2VTPDomain“ICND”©2000,CiscoSystems,Inc.—7-11VTPModesTransparent•Forwardsadvertisements•Synchronize•NotsavedinNVRAM•Createvlans•Modifyvlans•Deletevlans•Sends/forwardsadvertisements•Synchronize•SavedinNVRAM•Createvlans•Modifyvlans•Deletevlans•Forwardsadvertisements•Doesnotsynchronize•SavedinNVRAM©2000,CiscoSystems,Inc.—7-12HowVTPWorks•VTPadvertisementsaresentasmulticastframes•VTPserversandclientssynchronizedtolatestrevisionnumber•VTPadvertisementaresenteveryfiveminutesorwhenthereisachange©2000,CiscoSystems,Inc.—7-13•VTPadvertisementsaresentasmulticastframes•VTPserversandclientssynchronizedtolatestrevisionnumber•VTPadvertisementaresenteveryfiveminutesorwhenthereisachangeHowVTPWorks1.AddnewVLAN2.Rev3--Rev4ServerClientClient4.Rev3--Rev45.Syncnewvlaninfo334.Rev3--Rev45.Syncnewvlaninfo©2000,CiscoSystems,Inc.—7-14VTPPruning•Increasesavailablebandwidthbyreducingunnecessaryfloodedtraffic•Example:StationAsendsbroadcast,broadcastisonlyfloodedtowardanyswitchwithportsassignedtotheredVLANSwitch4Switch2Switch6Switch3Switch1Port2FloodedtrafficisprunedRedVLANPort1Switch5AB©2000,CiscoSystems,Inc.—7-15VLANConfigurationGuidelines•MaximumnumberofVLANsisswitch-dependent•Catalyst1900supports64VLANswithaseparatespanningtreeperVLAN•VLAN1isOneofthefactorydefaultVLANs•CDPandVTPadvertisementsaresentonVLAN1•Catalyst1900IPaddressisintheVLAN1broadcastdomain•MustbeinVTPserverortransparentmodetocreate,add,ordeleteVLANs©2000,CiscoSystems,Inc.—7-16VLANConfigurationSteps•EnableVTP(optional)•Enabletrunking•CreateVLANs•AssignVLANtoports©2000,CiscoSystems,Inc.—7-17•VTPdomainname•VTPmode(server/client/transparent)—VTPservermodeisthedefault•VTPpruning•VTPpassword•VTPtrapVTPConfigurationGuidelinesUsecautionwhenaddinganewswitchintoanexistingdomain.AnewswitchshouldbeaddedinclientmodetopreventthenewswitchfrompropagatingincorrectVLANsinformationUsethedeletevtpcommandtoresettheVTPrevisionnumber©2000,CiscoSystems,Inc.—7-18CreatingaVTPDomainvtp[server|transparent][domaindomain-name][trap{enable|disable}][passwordpassword][pruning{enable|disable}wg_sw_a(config)#©2000,CiscoSystems,Inc.—7-19CreatingaVTPDomainwg_sw_a#confterminalEnterconfigurationcommands,oneperline.EndwithCNTL/Zwg_sw_a(config)#vtptransparentwg_sw_a(config)#vtpdomainswitchlabvtp[server|transparent|client][domaindomain-name][trap{enable|disable}][passwordpassword][pruning{enable|disable}]wg_sw_a(config)#©2000,CiscoSystems,Inc.—7-20VerifyingVTPConfigurationswg_sw_a#showvtp©2000,CiscoSystems,Inc.—7-21VerifyingVT