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CONTENTS CHAPTER 1 ReadMeFirst 1 CHAPTER 2 ConfiguringtheCiscoIOSXEDHCPServer 3 FindingFeatureInformation 3 PrerequisitesforConfiguringtheDHCPServer 3 InformationAbouttheCiscoIOSXEDHCPServer 4 OverviewoftheDHCPServer 4 DatabaseAgents 4 AddressConflicts 4 DHCPAddressPoolConventions 4 DHCPAddressPoolSelection 5 AddressBindings 5 PingPacketSettings 6 DHCPAttributeInheritance 6 DHCPServerAddressAllocationUsingOption82 6 DHCPAddressAllocationUsingOption82FeatureDesign 8 UsageScenarioforDHCPAddressAllocationUsingOption82 8 DHCPClassCapability 8 HowtoConfiguretheCiscoIOSXEDHCPServer 9 ConfiguringaDHCPDatabaseAgentorDisablingConflictLogging 9 ExcludingIPAddresses 10 ConfiguringDHCPAddressPools 11 ConfiguringaDHCPAddressPool 11 ConfiguringaDHCPAddressPoolwithSecondarySubnets 16 TroubleshootingTips 21 VerifyingtheDHCPAddressPoolConfiguration 21 ConfiguringManualBindings 23 TroubleshootingTips 25 IP Addressing: DHCP Configuration Guide iii Contents ConfiguringDHCPStaticMapping 25 ConfiguringtheDHCPServertoReadaStaticMappingTextFile 27 CustomizingDHCPServerOperation 29 ConfiguringaRemoteDevicetoImportDHCPServerOptionsfromaCentralDHCP Server 31 ConfiguringtheCentralDHCPServertoUpdateDHCPOptions 31 ConfiguringtheRemoteDevicetoImportDHCPOptions 32 ConfiguringDHCPAddressAllocationUsingOption82 34 RestrictionsforDHCPAddressAllocationUsingOption82 34 EnablingOption82forDHCPAddressAllocation 35 TroubleshootingTips 35 DefiningtheDHCPClassandRelayAgentInformationPatterns 36 TroubleshootingTips 37 DefiningtheDHCPAddressPool 37 ConfiguringaStaticRoutewiththeNext-HopDynamicallyObtainedThroughDHCP 39 ClearingDHCPServerVariables 40 ConfigurationExamplesfortheCiscoIOSXEDHCPServer 41 Example:ConfiguringtheDHCPDatabaseAgent 41 Example:ExcludingIPAddresses 41 Example:ConfiguringDHCPAddressPools 42 Example:ConfiguringaDHCPAddressPoolwithMultipleDisjointSubnets 43 ConfiguringManualBindingsExample 44 Example:ConfiguringStaticMapping 45 ImportingDHCPOptionsExample 45 ConfiguringDHCPAddressAllocationUsingOption82Example 46 ConfiguringaStaticRoutewiththeNext-HopDynamicallyObtainedThroughDHCP Example 47 AdditionalReferences 47 FeatureInformationfortheCiscoIOSXEDHCPServer 48 CHAPTER 3 ConfiguringtheDHCPServerOn-DemandAddressPoolManager 51 FindingFeatureInformation 51 PrerequisitesforConfiguringtheDHCPServerOn-DemandAddressPoolManager 52 RestrictionsforConfiguringtheDHCPServerOn-DemandAddressPoolManager 52 InformationAbouttheDHCPServerOn-DemandAddressPoolManager 52 IP Addressing: DHCP Configuration Guide iv Contents ODAPManagerOperation 52 SubnetAllocationServerOperation 54 BenefitsofUsingODAPs 55 HowtoConfiguretheDHCPServerOn-DemandAddressPoolManager 55 DefiningDHCPODAPsastheGlobalDefaultMechanism 55 DefiningDHCPODAPsonanInterface 56 ConfiguringtheDHCPPoolasanODAP 57 ConfiguringODAPstoObtainSubnetsThroughIPCPNegotiation 59 ConfiguringAAA 61 ConfiguringRADIUS 62 ODAPAAAProfile 62 DisablingODAPs 64 VerifyingODAPOperation 65 TroubleshootingTips 68 MonitoringandMaintainingtheODAP 68 HowtoConfigureDHCPODAPSubnetAllocationServerSupport 70 ConfiguringaGlobalPoolonaSubnetAllocationServer 70 GlobalSubnetPools 70 ConfiguringaVRFSubnetPoolonaSubnetAllocationServer 71 VRFSubnetPools 71 UsingaVPNIDtoConfigureaVRFSubnetPoolonaSubnetAllocationServer 73 VRFPoolsandVPNIDs 73 VerifyingtheSubnetAllocationandDHCPBindings 75 TroubleshootingtheDHCPODAPSubnetAllocationServer 76 ConfigurationExamplesforDHCPServerOn-DemandAddressPoolManager 78 DefiningDHCPODAPsastheGlobalDefaultMechanismExample 78 DefiningDHCPODAPsonanInterfaceExample 78 ConfiguringtheDHCPPoolasanODAPExample 78 ConfiguringtheDHCPPoolasanODAPforNon-MPLSVPNsExample 80 ConfiguringAAAandRADIUSExample 81 ConfiguringaGlobalPoolforaSubnetAllocationServerExample 82 ConfiguringaVRFPoolforaSubnetAllocationServerExample 82 UsingaVPNIDtoConfigureaVRFPoolonaSubnetAllocationServerExample 82 VerifyingLocalConfigurationonaSubnetAllocationServerExample 82 VerifyingAddressPoolAllocationInformationExample 83 IP Addressing: DHCP Configuration Guide v Contents VerifyingSubnetAllocationandDHCPBindingsExample 83 AdditionalReferences 84 FeatureInformationfortheDHCPServerOn-DemandAddressPoolManager 85 Glossary 87 CHAPTER 4 ConfiguringtheCiscoIOSXEDHCPRelayAgent 89 FindingFeatureInformation 89 PrerequisitesforConfiguringtheDHCPRelayAgent 89 InformationAbouttheDHCPRelayAgent 90 DHCPRelayAgentOverview 90 PacketForwardingAddress 90 RelayAgentInformationOption 91 RelayAgentInformationReforwardingPolicy 92 DHCPRelayAgentSupportforMPLSVPNs 92 DHCPRelaySupportforOption82Encapsulation 94 HowtoConfiguretheDHCPRelayAgent 95 SpecifyingthePacketForwardingAddress 95 ConfiguringRelayAgentInformationOptionSupport 96 ConfiguringRelayAgentInformationOptionSupportperInterface 99 ConfiguringtheSubscriberIdentifierSuboptionoftheRelayAgentInformationOption 101 ConfiguringDHCPRelayAgentSupportforMPLSVPNs 102 SettingtheGatewayAddressoftheDHCPBroadcasttoaSecondaryAddressUsingSmart RelayAgentForwarding 104 ConfiguringRelayAgentInformationOptionEncapsulationSupport 105 TroubleshootingtheDHCPRelayAgent 106 ConfigurationExamplesfortheDHCPRelayAgent 107 ExampleConfiguringtheDHCPRelayAgentandRelayAgentInformationOption Support 107 ExampleConfiguringtheDHCPRelayAgentandRelayAgentInformationOptionSupport perInterface 108 ExampleConfiguringtheSubscriberIdentifierSuboption 108 ExampleConfiguringDHCPRelayAgentSupportforMPLSVPNs 109 ExampleConfiguringDHCPSmartRelayAgentForwarding 109 AdditionalReferences 109 TechnicalAssistance 111 IP Addressing: DHCP Configuration Guide vi Contents FeatureInformationfortheCiscoIOSXEDHCPRelayAgent 111 Glossary 113 CHAPTER 5 DHCPRelayServerIDOverrideandLinkSelectionOption82Suboptions 115 FindingFeatureInformation 115 RestrictionsforDHCPRelayServerIDOverrideandLinkSelectionOption82Suboptions 116 InformationAboutDHCPRelayServerIDOverrideandLinkSelectionOption82 Suboptions 116 ServerIDOverrideSuboption 116 LinkSelectionSuboption 116 DHCPRelayServerIDOverrideandLinkSelectionOption82SuboptionsFeatureDesign 116 HowtoConfigureSupportfortheDHCPRelayServerIDOverrideandLinkSelection Suboptions 118 ConfiguringtheDHCPRelayAgenttoInserttheDHCPServerIDOverrideandLinkSelection SuboptionsintoOption82 118 ConfigurationExamplesforDHCPRelayServerIDOverrideandLinkSelectionOption82 Suboptions 120 Example:DHCPRelayServerIDOverrideandLinkSelectionOption82Suboptions 120 AdditionalReferencesforDHCPRelayServerIDOverrideandLinkSelectionOption82 Suboptions 121 FeatureInformationforDHCPRelayServerIDOverrideandLinkSelectionOption82 Suboptions 122 Glossary 122 CHAPTER 6 DHCPServerRADIUSProxy 125 FindingFeatureInformation 125 PrerequisitesforDHCPServerRADIUSProxy 126 RestrictionsforDHCPServerRADIUSProxy 126 InformationAboutDHCPServerRADIUSProxy 126 DHCPServerRADIUSProxyOverview 126 DHCPServerRADIUSProxyArchitecture 126 DHCPServerandRADIUSTranslations 127 RADIUSProfilesforDHCPServerRADIUSProxy 129 HowtoConfigureDHCPServerRADIUSProxy 129 ConfiguringtheDHCPServerforRADIUS-basedAuthorization 129 IP Addressing: DHCP Configuration Guide vii Contents MonitoringandMaintainingtheDHCPServer 134 ConfigurationExamplesforDHCPServerRadiusProxy 136 ConfiguringtheDHCPServerExample 136 ConfiguringRADIUSProfilesExample 137 AdditionalReferences 137 TechnicalAssistance 138 FeatureInformationforDHCPServerRADIUSProxy 138 Glossary 139 CHAPTER 7 ConfiguringtheCiscoIOSXEDHCPClient 141 FindingFeatureInformation 141 InformationAbouttheDHCPClient 141 DHCPClientOperation 141 DHCPClientOverview 142 HowtoConfiguretheDHCPClient 143 ConfiguringtheDHCPClient 143 TroubleshootingTips 144 ConfigurationExamplesfortheDHCPClient 145 ConfiguringtheDHCPClientExample 145 CustomizingtheDHCPClientConfigurationExample 145 AdditionalReferences 145 TechnicalAssistance 147 FeatureInformationfortheCiscoIOSXEDHCPClient 147 CHAPTER 8 ConfiguringDHCPServicesforAccountingandSecurity 149 FindingFeatureInformation 149 PrerequisitesforConfiguringDHCPServicesforAccountingandSecurity 150 InformationAboutDHCPServicesforAccountingandSecurity 150 DHCPOperationinPublicWirelessLANs 150 SecurityVulnerabilitiesinPublicWirelessLANs 150 DHCPServicesforSecurityandAccountingOverview 150 DHCPLeaseLimits 151 HowtoConfigureDHCPServicesforAccountingandSecurity 151 ConfiguringAAAandRADIUSforDHCPAccounting 151 TroubleshootingTips 154 IP Addressing: DHCP Configuration Guide viii Contents ConfiguringDHCPAccounting 154 VerifyingDHCPAccounting 156 SecuringARPTableEntriestoDHCPLeases 157 TroubleshootingTips 158 ConfiguringaDHCPLeaseLimittoControltheNumberofSubscribersonanInterface 159 TroubleshootingTips 160 ConfigurationExamplesforDHCPServicesforAccountingandSecurity 161 Example:ConfiguringAAAandRADIUSforDHCPAccounting 161 Example:ConfiguringDHCPAccounting 161 Example:VerifyingDHCPAccounting 161 Example:ConfiguringaDHCPLeaseLimit 162 AdditionalReferences 162 TechnicalAssistance 164 FeatureInformationforDHCPServicesforAccountingandSecurity 164 CHAPTER 9 ISSUandSSO--DHCPHighAvailabilityFeatures 167 FindingFeatureInformation 168 PrerequisitesforDHCPHighAvailability 168 RestrictionsforDHCPHighAvailability 168 InformationAboutDHCPHighAvailability 168 ISSU 168 SSO 168 ISSUandSSO--DHCPServer 169 ISSUandSSO--DHCPRelayonUnnumberedInterface 169 ISSUandSSO--DHCPProxyClient 170 ISSUandSSO--DHCPODAPClientandServer 171 HowtoConfigureDHCPHighAvailability 172 ConfigurationExamplesforDHCPHighAvailability 172 AdditionalReferences 172 FeatureInformationforDHCPHighAvailabilityFeatures 174 Glossary 175 CHAPTER 10 DHCPv6RelayandServer-MPLSVPNSupport 177 FindingFeatureInformation 177 InformationAboutDHCPv6RelayandServer-MPLSVPNSupport 177 IP Addressing: DHCP Configuration Guide ix Contents DHCPv6ServerandRelay—MPLSVPNSupport 177 HowtoConfigureDHCPv6RelayandServer-MPLSVPNSupport 178 ConfiguringaVRF-AwareRelayandServerforMPLSVPNSupport 178 ConfiguringaVRF-AwareRelay 178 ConfiguringaVRF-AwareServer 180 ConfigurationExamplesforDHCPv6Server-MPLSVPNSupport 181 Example:ConfiguringaVRF-AwareRelay 181 Example:ConfiguringaVRF-AwareServer 181 AdditionalReferences 181 FeatureInformationforDHCPv6RelayandServer-MPLSVPNSupport 182 CHAPTER 11 IPv6AccessServices:DHCPv6RelayAgent 185 FindingFeatureInformation 185 InformationAboutIPv6AccessServices:DHCPv6RelayAgent 185 DHCPv6RelayAgent 185 DHCPv6RelayAgentNotificationforPrefixDelegation 187 DHCPv6RelayOptions:RemoteIDforEthernetInterfaces 187 DHCPv6RelayOptions:ReloadPersistentInterfaceIDOption 188 DHCPv6RelayChaining 188 HowtoConfigureIPv6AccessServices:DHCPv6RelayAgent 189 ConfiguringtheDHCPv6RelayAgent 189 ConfigurationExamplesforIPv6AccessServices:DHCPv6RelayAgent 190 Example:ConfiguringtheDHCPv6RelayAgent 190 AdditionalReferences 190 FeatureInformationforIPv6AccessServices:DHCPv6RelayAgent 191 CHAPTER 12 IPv6AccessServices:StatelessDHCPv6 193 FindingFeatureInformation 193 InformationAboutIPv6AccessServices:StatelessDHCPv6 193 InformationRefreshServerOption 193 SIPServerOptions 194 SNTPServerOption 194 HowtoConfigureIPv6AccessServices:StatelessDHCPv6 194 ConfiguringtheStatelessDHCPv6Function 194 ConfiguringtheStatelessDHCPv6Server 194 IP Addressing: DHCP Configuration Guide x