VXLAN-Design and Deployment · •Layer 2 connectivity between sites, providing VM mobility between...

VXLANDesignandDeployment

Aftab SiddiquiInternetSocietysiddiqui@isoc.org

Fundamentals

• VirtualeXtensible LAN(VXLAN)– definedunderRFC7348,co-authoredby:- CumulusNetworks,Arista,Broadcom,Cisco,RedHat,Vmware andIntel• VXLANoverlaysavirtualizedLayer2ontopofaLayer3networkallowingtheextensionofLayer2.• “MACinIP”Encapsulation• Layer2multi-pointtunnelingoverIPUDP• 50BytesHeader

• EnablesLayer2interconnectionacrossLayer3boundaries• TransparenttothephysicalIPnetwork• ProvidesLayer2scaleacrosstheLayer3IPfabric

Layer2Layer3

Layer2

Terminology

• VirtualTunnelEnd-point(VTEP).• TheVTEPactsastheentrypointforconnectinghostsintotheVXLANoverlaynetwork.• ThetaskoftheVTEPistoencap/decap withtheappropriateVXLANheader.• Itcanbeasoftwarevirtualswitchoraphysicalswitch.

• VirtualNetworkIdentifier(VNI)• A24-bitfieldaddedwithintheVXLANheader.• IdentifiestheLayer2segmentoftheencapsulatedEthernetframe• 16millionoptionsascompareto4000inVLAN

VTEP2CE1 VXLANVTEP1 CE2VLAN10

VLAN11

VLAN10

VLAN11

VNI10, VNI11

IP Network

WhyVXLAN

• SupportedinWideVarietyofPlatforms• Broadcom:TridentII/II+,Tomahawk• AristaNetworks,CiscoSystems,Dell,JuniperNetworks• WhiteLabel:BringYourOwnSwitch(BYOS)&PurchaseOperatingSystem(Cumulus,OcNOS &OtherstoFollow)• WidelyDeployedinManyNetworks

• SupportsPointtoPoint&Multi-Point• UDPHeader:• HashingWorksJustLikeAnyOtherUDPTraffic

• WideVendorSupport

VXLANPacket

Source:Cisco

VXLANPacket

VXLAN– withQinQ

VTEP2PE1 VXLANVTEP1 PE2S-Tag 600 S-Tag 600

VNI10, VNI11

IP Network

C-Tag 500 C-Tag 500

SW2(QinQ)PE1 SW1

(QinQ) PE2S-Tag 600 S-Tag 600

C-Tag 500 C-Tag 500Layer 2 Segment

VXLANPacket[QinQ]BeforeEncapsulation

AfterEncapsulation

UseCases:VXLAN– DataCenterInterconnect(DCI)• TointerconnectDataCentersacrossgeographicallydispersesites• Layer2connectivitybetweensites,providingVMmobilitybetweensites• WithintheDCforservermigrationbetweenPODs,forintegratingnewinfrastructure

Datacenter 1

Datacenter 2

Datacenter 3

VNI

VNI

VNI

UseCases:VXLAN– CloudProvider• ProviderlookingtosupportmultiplecustomersoverasharedL3infrastructure.• Wantstheflexibilitytodeploytenantresourcesacrossracks.• Layer2(VXLANbridging)requiredtostitchthetenant’sresources/appliancestogetheracrossracks.

• VRFcanbeusedtosegregatetenantrouting.• FabricVTEPthusonlyrequiredtoprovidelayer2VXLANbridgingservice

Layer 3 Fabric

VNI

VNI

TOR TOR TOR

VXLAN– Notforeverything

• Worksfine:• Routingprotocols• VLAN• QinQ• Multicast

• Doesn’tWork• LLDP(workslocallyonly)• LACP(workslocallyonly)• CoS Preservation• 802.1x

Summary

• OperationallySimpleEthernetLineServices• EliminateProtocolDependency&Complexity• ExpandVendorChoice

• Practical&EconomicalDeployments• DeployServicesOverLegacyNetworksorIPOnlyNetworks• DeployServicesOverOtherProvidersNetworks

• FutureUseCases:• RemoteTAPTransport• HubandSpokeELINEServices• MoreMobileManagementApplicationstodeliverSelfServices

AnyQuestions?