IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS XE

84 Pages·2015·3.35 MB·English

IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS XE
Release 3S
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CONTENTS
CHAPTER 1 ConfiguringIPv4Addresses 1
FindingFeatureInformation 1
InformationAboutIPAddresses 2
BinaryNumbering 2
IPAddressStructure 4
IPAddressClasses 5
IPNetworkSubnetting 7
IPNetworkAddressAssignments 9
ClasslessInter-DomainRouting 11
Prefixes 11
HowtoConfigureIPAddresses 12
EstablishingIPConnectivitytoaNetworkbyAssigninganIPAddresstoanInterface 12
TroubleshootingTips 13
IncreasingtheNumberofIPHoststhatAreSupportedonaNetworkbyUsingSecondaryIP
Addresses 13
TroubleshootingTips 14
WhattoDoNext 15
MaximizingtheNumberofAvailableIPSubnetsbyAllowingtheUseofIPSubnetZero 15
TroubleshootingTips 16
SpecifyingtheFormatofNetworkMasks 16
SpecifyingtheFormatinWhichNetmasksAppearfortheCurrentSession 17
SpecifyingtheFormatinWhichNetmasksAppearforanIndividualLine 17
UsingIPUnnumberedInterfacesonPoint-to-PointWANInterfacestoLimitNumberofIP
AddressesRequired 18
IPUnnumberedFeature 18
TroubleshootingTips 20
UsingIPaddresseswith31-BitPrefixesonPoint-to-PointWANInterfacestoLimitNumber
ofIPAddressesRequired 20
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Contents
RFC3021 21
TroubleshootingTips 23
ConfigurationExamplesforIPAddresses 23
ExampleEstablishingIPConnectivitytoaNetworkbyAssigninganIPAddresstoan
Interface 23
ExampleIncreasingtheNumberofIPHoststhatareSupportedonaNetworkbyUsing
SecondaryIPAddresses 24
ExampleUsingIPUnnumberedInterfacesonPoint-to-PointWANInterfacestoLimit
NumberofIPAddressesRequired 24
ExampleUsingIPaddresseswith31-BitPrefixesonPoint-to-PointWANInterfacesto
LimitNumberofIPAddressesRequired 25
ExampleMaximizingtheNumberofAvailableIPSubnetsbyAllowingtheUseofIPSubnet
Zero 25
WheretoGoNext 25
AdditionalReferences 25
FeatureInformationforIPAddresses 27
CHAPTER 2 IPOverlappingAddressPools 29
FindingFeatureInformation 29
RestrictionsforIPOverlappingAddressPools 29
InformationAboutIPOverlappingAddressPools 30
Benefits 30
HowIPAddressGroupsWork 30
HowtoConfigureIPOverlappingAddressPools 30
ConfiguringandVerifyingaLocalPoolGroup 30
ConfigurationExamplesforConfiguringIPOverlappingAddressPools 31
DefineLocalAddressPoolingastheGlobalDefaultMechanismExample 31
ConfigureMultipleRangesofIPAddressesintoOnePoolExample 31
AdditionalReferences 32
FeatureInformationforConfiguringIPOverlappingAddressPools 33
Glossary 34
CHAPTER 3 IPUnnumberedEthernetPollingSupport 35
FindingFeatureInformation 35
InformationAboutIPUnnumberedEthernetPollingSupport 35
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Contents
IPUnnumberedEthernetPollingSupportOverview 35
HowtoConfigureIPUnnumberedEthernetPollingSupport 36
EnablingPollingonanEthernetInterface 36
ConfiguringtheQueueSizeandthePacketRateforIPARPPollingforUnnumbered
Interfaces 37
VerifyingIPUnnumberedEthernetPollingSupport 38
ConfigurationExamplesforIPUnnumberedEthernetPollingSupport 40
Example:EnablingPollingonanEthernetInterface 40
Example:ConfiguringtheQueueSizeandthePacketRateforIPARPPollingforUnnumbered
Interfaces 40
AdditionalReferences 40
FeatureInformationforIPUnnumberedEthernetPollingSupport 41
CHAPTER 4 Auto-IP 43
FindingFeatureInformation 44
PrerequisitesforAuto-IP 44
RestrictionsforAuto-IP 44
InformationAboutAuto-IP 45
Auto-IPOverview 45
SeedDevice 47
Auto-IPConfigurationforInsertingaDeviceintoanAuto-IPRing 48
DeviceRemovalfromanAuto-IPRing 50
ConflictResolutionUsingtheAuto-SwapTechnique 50
HowtoConfigureAuto-IP 52
ConfiguringaSeedDevice 52
ConfiguringtheAuto-IPFunctionalityonNodeInterfaces(forInclusioninanAuto-IP
Ring) 55
VerifyingandTroubleshootingAuto-IP 57
ConfigurationExamplesforAuto-IP 59
Example:ConfiguringaSeedDevice 59
Example:ConfiguringtheAuto-IPFunctionalityonNodeInterfaces(forInclusioninanAuto-IP
Ring) 59
AdditionalReferencesforAuto-IP 60
FeatureInformationforAuto-IP 61
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Contents
CHAPTER 5 ZeroTouchAuto-IP 63
FindingFeatureInformation 63
PrerequisitesforZeroTouchAuto-IP 64
RestrictionsforZeroTouchAuto-IP 64
InformationAboutZeroTouchAuto-IP 64
HowtoConfigureZeroTouchAuto-IP 66
AssociatinganAuto-IPServerwithanAutonomicNetwork 66
EnablingAutoModeonAuto-IPRingPorts 68
ConfiguringanAuto-IPServerandReservingaPoolofIPAddressesontheServer 70
ConfiguringaSeedPort 71
VerifyingandTroubleshootingZeroTouchAuto-IP 72
ConfigurationExamplesforZeroTouchAuto-IP 75
Example:AssociatinganAuto-IPServerwithanAutonomicNetwork 75
Example:EnablingAutoModeonAuto-IPRingPorts 75
Example:ConfiguringanAuto-IPServerandReservingaPoolofIPAddressesonthe
Server 75
Example:ConfiguringaSeedPort 75
AdditionalReferencesforZeroTouchAuto-IP 76
FeatureInformationforAuto-IP 76
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1
CHAPTER
Configuring IPv4 Addresses
Thischaptercontainsinformationabout,andinstructionsforconfiguringIPv4addressesoninterfacesthat
arepartofanetworkingdevice.
Note AllfurtherreferencestoIPv4addressesinthisdocumentuseonlyIPinthetext,notIPv4.
• FindingFeatureInformation, page 1
• InformationAboutIPAddresses, page 2
• HowtoConfigureIPAddresses, page 12
• ConfigurationExamplesforIPAddresses, page 23
• WheretoGoNext, page 25
• AdditionalReferences, page 25
• FeatureInformationforIPAddresses, page 27
Finding Feature Information
Yoursoftwarereleasemaynotsupportallthefeaturesdocumentedinthismodule.Forthelatestcaveatsand
featureinformation,seeBugSearchToolandthereleasenotesforyourplatformandsoftwarerelease.To
findinformationaboutthefeaturesdocumentedinthismodule,andtoseealistofthereleasesinwhicheach
featureissupported,seethefeatureinformationtableattheendofthismodule.
UseCiscoFeatureNavigatortofindinformationaboutplatformsupportandCiscosoftwareimagesupport.
ToaccessCiscoFeatureNavigator,gotowww.cisco.com/go/cfn.AnaccountonCisco.comisnotrequired.
IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS XE Release 3S
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Configuring IPv4 Addresses
Information About IP Addresses
Information About IP Addresses
Binary Numbering
IPaddressesare32bitslong.The32bitsaredividedintofouroctets(8-bits).Abasicunderstandingofbinary
numberingisveryhelpfulifyouaregoingtomanageIPaddressesinanetworkbecausechangesinthevalues
ofthe32bitsindicateeitheradifferentIPnetworkaddressorIPhostaddress.
Avalueinbinaryisrepresentedbythenumber(0or1)ineachpositionmultipliedbythenumber2tothe
powerofthepositionofthenumberinsequence,startingwith0andincreasingto7,workingrighttoleft.
Thefigurebelowisanexampleofan8-digitbinarynumber.
Figure 1: Example of an 8-digit Binary Number
IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS XE Release 3S
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Configuring IPv4 Addresses
Binary Numbering
Thefigurebelowprovidesbinarytodecimalnumberconversionfor0through134.
Figure 2: Binary to Decimal Number Conversion for 0 to 134
IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS XE Release 3S
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Configuring IPv4 Addresses
IP Address Structure
Thefigurebelowprovidesbinarytodecimalnumberconversionfor135through255.
Figure 3: Binary to Decimal Number Conversion for 135 to 255
IP Address Structure
AnIPhostaddressidentifiesadevicetowhichIPpacketscanbesent.AnIPnetworkaddressidentifiesa
specificnetworksegmenttowhichoneormorehostscanbeconnected.Thefollowingarecharacteristicsof
IPaddresses:
•IPaddressesare32bitslong
•IPaddressesaredividedintofoursectionsofonebyte(octet)each
•IPaddressesaretypicallywritteninaformatknownasdotteddecimal
ThetablebelowshowssomeexamplesofIPaddresses.
Table 1: Examples of IP Addresses
IP Addresses in Dotted Decimal IP Addresses in Binary
10.34.216.75 00001010.00100010.11011000.01001011
172.16.89.34 10101100.00010000.01011001.00100010
192.168.100.4 11000000.10101000.01100100.00000100
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