AristaVXLAN功能介绍

1VXLANFundamentals,Architecture&Roadmap2TableofContents1.DataCenterIPFabric‘BuildingastrongFoundation’2.Whatis‘NetworkVirtualization’?3.VXLANOverview4.VXLANPacketdetails5.VXLANTerminology6.VXLANHostDiscovery7.VXLANBUMTrafficHandling8.VXLANLayer2&Layer3Terminologies9.VXLANAristaArchitecture&Vision10.VXLANRoadmap11.VXLANVisbility3DataCenter–‘IPFabric’BuildingAStrongFoundationChallengeswithcurrentnetworkarchitectureScalabilityScalesupandnotscalesoutDependentonspecifichardware(mix&match)Notscalableto40GbE/100GbELatencyHighlatencyLowpredictabilityMobilityWhathappensifmy“IP”changes?Whathappensiftrafficpatternchanges?CostAsmultiplelayers,itcanget$$$OversubscriptionPortsondevicesareoversubscribed~8:1HigherOversubscriptionastraffictraversesnorth~20:1Multiplepointsofmanagement,rampantoversubscription,wastefulcostmodelLayer2DomainLayer2DomainLegacyDataCenterModelMultiplepointsofmanagement,rampantoversubscription,wastefulcostmodelLayer2DomainLayer2DomainNorthtoSouthDataCenter‘IPFabric’SupportforEast/West80:20trafficpatternScaleupto64-wayECMPSpinedesignsAlluplinksfromToRareActive/ActiveSupport100’000sofhostportsNon-blocking/Non-oversubscribedarchitectureDeployL3routingprotocolsbetweenleaf&spinei.e.BGP,OSPF,orISISEverythingisonly3hopsaway!Providenetworkmobilityvia‘OverlayNetwork’6Arista–Spine/Leaf“IPFabric”ArchitectureVTEP1IPFabricSpineTierLeafTierA1B1A2B2BareMetalServersBareMetalStorageHYPERVISOR1HYPERVISOR2VTEP2VTEP3VTEP4NetworkcoreisanIPfabriclaidoutinaLeaf-SpinearchitecturerunningECMPbetweenthetwotiers-Leafswitches-Arista7150-xor7050Q-xmodelsaredeployedattheTORconnectingvirtualizedservers,bare-metalservers,storagearraysandotherdevices-Spineswitches–Arista7500’saredeployedatthecore-RoutingProtocol–EitherEGP(BGP)orIGP(OSPF/ISIS)isrunintheIPfabric7WhatisNetworkVirtualization?8WhatisNetworkVirtualization?NetworkVirtualizationisnotthesameasServerVirtualization!9OverlaysvUnderlaysNetworkvirtualization:abilitytoseparate,abstractanddecouplethephysicaltopologyfroma‘logical’or‘virtual’topologybyusingencapsulatedtunneling.Thislogicalnetworktopologyisoftenreferredtoasan‘OverlayNetwork’.OverlayNetworkPhysicalInfrastructurei.e.UnderlayNetworkVXLANdisassociatesworkloadsfromphysicalnetworks,allowingforpossibletransitiontocloudbasedproviders10Typesof‘Overlay’TechnologiesAnyOverlaytechnologyusesLocation&IdentityseparationLocationIdentityFabricPathVXLANOTVLISPUnderlayProtocolIS-ISBGP,OSPF,IS-ISBGP,OSPF,IS-ISBGP,OSPF,IS-ISLocationSwitch-IDIPaddressIPaddressIPaddressIdentityClientMACClientMACClientMACClientIP/MacIdentityLearningFloodingFlooding/DynamiclearningIS-ISMappingDBVendorProprietaryYesNonYesNonIntra&/orInterDCIntraBothBothInter11VXLANOverview12VirtualExtensibleLocalAreaNetwork(VXLAN)EthernetinIPoverlaynetwork•EntireL2frameencapsulatedinUDP•50bytesofoverheadInclude24bitVXLANIdentifier•16MlogicalnetworksVXLANcancrossLayer3TunnelbetweenESXhosts•VMsdoNOTseeVXLANIDIPmulticastusedforL2broadcast/multicast,unknownunicastTechnologysubmittedtoIETFforstandardization•WithArista,Vmware,RedHat,Citrix,Cisco,andOthersOuterMACDAOuterMACSAOuter802.1QOuterIPDAOuterIPSAOuterUDPVXLANID(24bits)InnerMACDAInnerMACSAOptionalInner802.1QOriginalEthernetPayloadCRCVXLANEncapsulationOriginalEthernetFrame13VirtualeXtensibleLAN:Howdoesitwork?MAC&IPareUDPEncapsulatedEncapsulationatVTEPnodeistransparenttoIPECMPfabricVM-110.10.10.1/24VM-210.10.10.2/24Subnet-ASubnet-BLayer2DomainbetweentheVMvWire-VNI10HWVTEPEncap/DecapVXLANFramesSWVTEPEncap/DecapVXLANVTEPVTEPVTEP14VXLANBenefitsFeatureBenefits-Eliminatescurrentnetworkingchallengesinthewayofon-demand,virtualenvironment:-VLANSprawl-Singlefaultdomains-Scalabilitybeyond4096segments-Proprietaryfabricsolutions-IPmobility-Physicalclustersizeandlocality-Enablesmulti-tenancyatscale-Decoupleslogicalnetworksfromphysicalinfrastructuresothatapplicationscanbedeployedwithoutworryingaboutphysicalracklocation,IPaddressorVLAN-Basedonopenandwellknownstandards15VXLANUseCasesPhysicaltoVirtualinternetworkingMulti-hypervisorconnectivityandintegrationMulti-tenantCloudenvironmentsHAclustersacrossfailuredomainsDynamicgrowthDynamicresourcemanagement16VXLANPacketDetails17VXLANPacketVXLANisaMAC-in-IPencapsulation18VXLANHeaderVXLANHeaderisa8Bytefieldcomprisingof:(a)Flags(8Bits)(b)VxLANNetworkIdentifier(VNI)(24Bits)(c)Reserved(24&8Bits)–Alwayssettozero.Reserved(24&8Bits)–Alwayssettozero.Flags(8Bits)–Iflagissetto1foravalidVxLANNetworkID(VNI).Theremaining7bits(designatedR)arereservedfieldsandsettozero.VxLANNetworkIdentifier(VNI)(24Bits)–UsedforidentificationoftheindividualVxLANoverlaynetworkonwhichthecommunicatingVMsaresituated.VMsindifferentVxLANoverlaynetworkscannotcommunicate.19VXLANTerminology20VXLANSegmentsVXLANTerminology–PhysicalTopologySoftwareVTEPHardwareVTEPVTEP1IPFabricSpineTierLeafTierA1B1A2B2BareMetalServersBareMetalStorageHYPERVISOR1HYPERVISOR2VTEP2VTEP3VTEP4VTIVXLANGatewayVTIVXLAN10001VXLAN1000221VNIB2VTEP4A210.100.1.0/2410.100.2.0/24.10.11.2.3VXLAN10001VXLAN10002.10.2VARPDefaultGateway:10.100.1.