IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS Release 15S

78 Pages·2015·3.3 MB·English

IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS
Release 15S
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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 IPUnnumberedEthernetPollingSupport 29
FindingFeatureInformation 29
InformationAboutIPUnnumberedEthernetPollingSupport 29
IPUnnumberedEthernetPollingSupportOverview 29
HowtoConfigureIPUnnumberedEthernetPollingSupport 30
EnablingPollingonanEthernetInterface 30
ConfiguringtheQueueSizeandthePacketRateforIPARPPollingforUnnumbered
Interfaces 31
VerifyingIPUnnumberedEthernetPollingSupport 32
ConfigurationExamplesforIPUnnumberedEthernetPollingSupport 34
Example:EnablingPollingonanEthernetInterface 34
Example:ConfiguringtheQueueSizeandthePacketRateforIPARPPollingfor
UnnumberedInterfaces 34
AdditionalReferences 34
FeatureInformationforIPUnnumberedEthernetPollingSupport 35
CHAPTER 3 Auto-IP 37
FindingFeatureInformation 38
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PrerequisitesforAuto-IP 38
RestrictionsforAuto-IP 38
InformationAboutAuto-IP 39
Auto-IPOverview 39
SeedDevice 41
Auto-IPConfigurationforInsertingaDeviceintoanAuto-IPRing 42
DeviceRemovalfromanAuto-IPRing 44
ConflictResolutionUsingtheAuto-SwapTechnique 44
HowtoConfigureAuto-IP 46
ConfiguringaSeedDevice 46
ConfiguringtheAuto-IPFunctionalityonNodeInterfaces(forInclusioninanAuto-IP
Ring) 49
VerifyingandTroubleshootingAuto-IP 51
ConfigurationExamplesforAuto-IP 53
Example:ConfiguringaSeedDevice 53
Example:ConfiguringtheAuto-IPFunctionalityonNodeInterfaces(forInclusioninanAuto-IP
Ring) 53
AdditionalReferencesforAuto-IP 54
FeatureInformationforAuto-IP 55
CHAPTER 4 ZeroTouchAuto-IP 57
FindingFeatureInformation 57
PrerequisitesforZeroTouchAuto-IP 58
RestrictionsforZeroTouchAuto-IP 58
InformationAboutZeroTouchAuto-IP 58
HowtoConfigureZeroTouchAuto-IP 60
AssociatinganAuto-IPServerwithanAutonomicNetwork 60
EnablingAutoModeonAuto-IPRingPorts 62
ConfiguringanAuto-IPServerandReservingaPoolofIPAddressesontheServer 64
ConfiguringaSeedPort 65
VerifyingandTroubleshootingZeroTouchAuto-IP 66
ConfigurationExamplesforZeroTouchAuto-IP 69
Example:AssociatinganAuto-IPServerwithanAutonomicNetwork 69
Example:EnablingAutoModeonAuto-IPRingPorts 69
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Example:ConfiguringanAuto-IPServerandReservingaPoolofIPAddressesonthe
Server 69
Example:ConfiguringaSeedPort 69
AdditionalReferencesforZeroTouchAuto-IP 70
FeatureInformationforAuto-IP 70
IP Addressing: IPv4 Addressing Configuration Guide, Cisco IOS Release 15S
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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 Release 15S
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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 Release 15S
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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 Release 15S
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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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