Cisco Router Configuration Tutorial

Contents

1. What's covered2. Getting started3. Cisco RouterConfiguration3.1 Global configuration3.2 Configuring interfaces3.3 Routing3.4 IPv6 configurationwith IOS3.5 Saving yourconfiguration3.6 Example configuration4. Troubleshooting5. References6. More information

This work is licensedunder a CreativeCommons License.

PDF versionnow available.

Cisco Router ConfigurationTutorialJosh Gentry, [email protected], 14 May, 2011

This document covers basic Cisco router IP configuration using thecommand-line interface

AcknowledgmentsThe following sources where extremely useful:

Leinwand, Pinsky, and Culpepper. Cisco Router Configuration.Indianapolis, Indiana: Cisco Press, 1998.Cisco Systems, Inc., http://www.cisco.com

DisclaimerThis document carries no explicit or implied warranty. Nor is there anyguarantee that the information contained in this document is accurate. It isoffered in the hopes of helping others, but you use it at your own risk. Theauthor will not be liable for any damages that occur as a result of using thisdocument.

ConventionsImportant terms and concepts, when they are introduced, may be displayed inbold. Commands included in the body of the text will be displayed in this

font. All names and addresses used in examples are just that, examples, andshould not be used on your network. Do not type them in verbatim whenconfiguring your system. Finally, in some examples where the commandrquires an IP address as an argument, the IP address may be represented inthis way, xx.xx.xx.xx, or aa.bb.cc.dd. You will never actually use these stringswhen configuring your system. They are mearly a convention of thisdocument to specify that you should substitute the appropriate IP address atthat point.

Cisco Configuration tool

Free Configuration Management toolfor Cisco Routers Switches Firewall

ManageEngine.com/DeviceExpert

Cisco Router Configuration Tutorial http://pages.swcp.com/~jgentry/topo/cisco.htm

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1. What this documentcovers

There are several methods available forconfiguring Cisco routers. It can bedone over the network from a TFTPserver. It can be done through themenu interface provided at bootup, andit can be done from the menu interfaceprovided by using the command setup.This tutorial does not cover thesemethods. It covers configuration fromthe IOS command-line interface only.Useful for anyone new to Ciscorouters, and those studying for CCNA.

Note that this tutorial does not coverphysically connecting the router to thenetworks it will be routing for. Itcovers operating system configurationonly.

1.1 Reasons for using thecommand-line

The main reason for using thecommand-line interface instead of amenu driven interface is speed. Onceyou have invested the time to learn thecommand-line commands, you canperform many operations much morequickly than by using a menu. This isbasically true of all command-line vs.menu interfaces. What makes itespecially efficient to learn thecommand-line interface of the CiscoIOS is that it is standard across allCisco routers. Also, some questions onthe CCNA exam require you to knowcommand-line commands.

2. Getting started withCisco

Initially you will probably configureyour router from a terminal. If therouter is already configured and atleast one port is configured with an IPaddress, and it has a physicalconnection to the network, you mightbe able to telnet to the router andconfigure it across the network. If it isnot already configured, then you willhave to directly connect to it with a


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terminalandaserialcable.WithanyWindowsboxyoucanuseHyperterminaltoeasilyconnecttotherouter.Plugaserialcableintoaserial(COM)portonthePCandtheotherendintotheconsoleportontheCiscorouter.StartHyperterminal,tellitwhichCOMporttouseandclickOK.Setthespeed


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oftheconnectionto9600baud

andclickOK.Iftherouterisnoton,turniton.

IfyouwishtoconfiguretherouterfromaLinuxbox,eitherSeyonorMinicomshouldwork.Atleastoneofthem,andmaybeboth,willcomewithyourLinuxdistribution.

OftenyouwillneedtohittheEnter


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keytoseethepromptfromtherouter.Ifitisunconfigureditwilllooklikethis:

Router>

Ifithasbeenpreviouslyconfiguredwithahostname,itwilllooklikethis:

hostnameofrouter>

Ifyouhavejustturnedontherouter,afteritbootsitwillaskyouifyouwishtobegininitial


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configuration.Sayno.Ifyousayyes,itwillputyouinthemenuinterface.Sayno.

2.1Modes

TheCiscoIOScommand-lineinterfaceisorganizedaroundtheideaofmodes.Youmoveinandoutofseveraldifferentmodeswhileconfiguringarouter,andwhichmodeyouareindetermineswhatcommandsyoucanuse.


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Eachmodehasasetofcommandsavailableinthatmode,andsomeofthesecommandsareonlyavailableinthatmode.Inanymode,typingaquestionmarkwilldisplayalistofthecommandsavailableinthatmode.

Router>?

2.2Unprivilegedandprivilegedmodes

Whenyoufirstconnecttotherouterandprovide


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thepassword(ifnecessary),youenterEXECmode,thefirstmodeinwhichyoucanissuecommandsfromthecommand-line.Fromhereyoucanusesuchunprivilegedcommandsasping,telnet,and

rlogin.

Youcanalsousesomeoftheshow

commandstoobtaininformationaboutthesystem.Inunprivilegedmodeyouusecommandslike,show

version

todisplay


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theversionoftheIOStherouterisrunning.Typingshow

?

willdiplayalltheshow

commandsavailableinthemodeyouarepresentlyin.

Router>show?

Youmustenterprivilegedmodetoconfiguretherouter.Youdothisbyusingthecommandenable.Privilegedmodewillusuallybepasswordprotectedunlesstherouterisunconfigured.


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Youhavetheoptionofnotpasswordprotectingprivilegedmode,butitisHIGHLYrecommendedthatyoudo.Whenyouissuethecommandenable

andprovidethepassword,youwillenterprivilegedmode.

Tohelptheuserkeeptrackofwhatmodetheyarein,thecommand-linepromptchangeseachtimeyouenteradifferentmode.When


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youswitchfromunprivilegedmodetoprivilegedmode,thepromptchangesfrom:

Router>

to

Router#

Thiswouldprobablynotbeabigdealiftherewerejusttwomodes.Thereare,infact,numerousmodes,andthisfeatureisprobablyindispensable.Paycloseattentiontothepromptatalltimes.

Withinprivilegedmodethere


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aremanysub-modes.InthisdocumentIdonotcloselyfollowCiscoterminologyforthishierarchyofmodes.Ithinkthatmyexplanationisclearer,frankly.Ciscodescribestwomodes,unprivilegedandprivileged,andthenahierarchyofcommandsusedinprivilegedmode.Ireasonthatitismuchclearertounderstandifyoujustconsiderthereto


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bemanysub-modesofprivilegedmode,whichIwillalsocallparentmode.Onceyouenterprivilegedmode(parentmode)thepromptendswithapoundsign(#).Therearenumerousmodesyoucanenteronlyafterenteringprivilegedmode.Eachofthesemodeshasapromptoftheform:

Router(arguments)#

Theystillallendwith


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thepoundsign.Theyaresubsumedwithinprivilegedmode.Manyofthesemodeshavesub-modesoftheirown.Onceyouenterpriligedmode,youhaveaccesstoalltheconfigurationinformationandoptionstheIOSprovides,eitherdirectlyfromtheparentmode,orfromoneofitssubmodes.

3.ConfiguringyourCiscoRouter


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Ifyouhavejustturnedontherouter,itwillbecompletelyunconfigured.Ifitisalreadyconfigured,youmaywanttoviewitscurrentconfiguration.Evenifithasnotbeenpreviouslyconfigured,youshouldfamiliarizeyourselfwiththeshow

commandsbeforebeginningtoconfiguretherouter.Enterprivilegedmodebyissuingthecommandenable,then


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issueseveralshow

commandstoseewhattheydisplay.Remember,thecommandshow

?

willdisplayalltheshowcommandsaavailableinthecurrentmode.Definatelytryoutthefollowingcommands:

Router#showinterfacesRouter#showipprotocolsRouter#showipv6protocolsRouter#showiprouteRouter#showipv6routeRouter#showiparpRouter#showipv6neighbors

Whenyouenterprivilegedmodebyusingthecommandenable,you


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areinthetop-levelmodeofprivilegedmode,alsoknowninthisdocumentas"parentmode."Itisinthistop-levelorparentmodethatyoucandisplaymostoftheinformationabouttherouter.Asyounowknow,youdothiswiththeshow

commands.Hereyoucanlearntheconfigurationofinterfacesandwhethertheyare


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upordown.YoucandisplaywhatIPprotocolsareinuse,suchasdynamicroutingprotocols.YoucanviewtherouteandARPtables,andthesearejustafewofthemoreimportantoptions.

Asyouconfiguretherouter,youwillentervarioussub-modestosetoptions,thenreturntotheparentmodetodisplay


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theresultsofyourcommands.Youalsoreturntotheparentmodetoenterothersub-modes.Toreturntotheparentmode,youhitctrl-z.Thisputsanycommandsyouhavejustissuedintoaffect,andreturnsyoutoparentmode.

3.1Globalconfiguration(config)

Toconfigureanyfeatureoftherouter,youmustenter


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configurationmode.Thisisthefirstsub-modeoftheparentmode.Intheparentmode,youissuethecommandconfig.

Router#configRouter(config)#

Asdemonstratedabove,thepromptchangestoindicatethemodethatyouarenowin.

Inconnfigurationmodeyoucansetoptionsthatapplysystem-wide,alsoreferedtoas"globalconfigurations."Forinstance,it


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isagoodideatonameyourroutersothatyoucaneasilyidentifyit.Youdothisinconfigurationmodewiththehostname

command.

Router(config)#hostnameExampleNameExampleName(config)#

Asdemonstratedabove,whenyousetthenameofthehostwiththehostname

command,thepromptimmediatelychangesbyreplacingRouter

withExampleName.(Note:Itisagood


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ideatonameyourrouterswithanorganizednamingscheme.)

AnotherusefulcommandissuedfromconfigmodeisthecommandtodesignatetheDNSservertobeusedbytherouter:

ExampleName(config)#ipname-serveraa.bb.cc.ddExampleName(config)#ctrl-ZExampleName#

Thisisalsowhereyousetthepasswordforprivilegedmode.

ExampleName(config)#enablesecretexamplepasswordExampleName(config)#ctrl-ZExampleName#

Untilyouhitctrl-Z


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(ortypeexit

untilyoureachparentmode)yourcommandhasnotbeenputintoaffect.Youcanenterconfigmode,issueseveraldifferentcommands,thenhitctrl-Z

toactivatethemall.Eachtimeyouhitctrl-Z

youreturntoparentmodeandtheprompt:

ExampleName#

Hereyouuseshow

commandstoverifytheresultsofthe


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commandsyouissuedinconfigmode.Toverifytheresultsoftheip

name-server

command,issuethecommandshow

host.

3.2ConfiguringCiscorouterinterfaces

Ciscointerfacenamingisstraightforward.Individualinterfacesarereferredtobythisconvention:

mediatypeslot#/port#

"Mediatype"referstothetypeofmediathattheportisaninterface


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for,suchasEthernet,TokenRing,FDDI,serial,etc.Slotnumbersareonlyapplicableforroutersthatprovideslotsintowhichyoucaninstallmodules.Thesemodulescontainseveralportsforagivenmedia.The7200seriesisanexample.Thesemodulesareevenhot-swapable.Youcanremoveamodulefromaslotandreplaceitwitha


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differentmodule,withoutinterruptingserviceprovidedbytheothermodulesinstalledintherouter.Theseslotsarenumberedontherouter.

Portnumberreferstotheportinreferencetotheotherportsinthatmodule.Numberingisleft-to-right,andallnumberingstartsat0,notatone.

Forexample,aCisco7206isa


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7200seriesrouterwithsixslots.TorefertoaninterfacethatisthethirdportofanEthernetmoduleinstalledinthesixthslot,itwouldbeinterfaceethernet6/2.Therefor,todisplaytheconfigurationofthatinterfaceyouusethecommand:

ExampleName#showinterfaceethernet6/2

Ifyourrouterdoesnothaveslots,likea1600,


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thentheinterfacenameconsistsonlyof:

mediatypeport#

Forexample:

ExampleName#showinterfaceserial0

HereisanexampleofconfiguringaserialportwithanIPaddress:

ExampleName#configExampleName(config)#interfaceserial1/1ExampleName(config-if)#ipaddress192.168.155.2255.255.255.0ExampleName(config-if)#ipv6addressfe80::230:1bff:fe80:b8ea/64ExampleName(config-if)#ipv6enableExampleName(config-if)#noshutdownExampleName(config-if)#ctrl-ZExampleName#

Thentoverifyconfiguration:

ExampleName#showinterface


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serial1/1

Notetheno

shutdown

command.Aninterfacemaybecorrectlyconfiguredandphysicallyconnected,yetbe"administrativelydown."Inthisstateitwillnotfunction.Thecommandforcausinganinterfacetobeadministrativelydownisshutdown.

ExampleName(config)#interfaceserial1/1ExampleName(config-if)#shutdownExampleName(config-if)#ctrl-ZExampleName#showinterfaceserial1/1

IntheCiscoIOS,thewaytoreverseor


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deletetheresultsofanycommandistosimplyputno

infrontofit.Forinstance,ifwewantedtounassigntheIPaddresswehadassignedtointerfaceserial1/1:

ExampleName(config)#interfaceserail1/1ExampleName(config-if)#noipaddress192.168.155.2255.255.255.0ExampleName(config-if)ctrl-ZExampleName#showinterfaceserial1/1

ConfiguringmostinterfacesforLANconnectionsmightconsistonlyofassigninganetworklayer


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addressandmakingsuretheinterfaceisnotadministrativelyshutdown.Itisusuallynotnecessarytostipulatedata-linklayerencapsulation.Notethatitisoftennecessarytostipulatetheappropriatedata-linklayerencapsulationforWANconnections,suchasframe-relayandATM.SerialinterfacesdefaulttousingHDLC.Adiscussionofdata-linkprotocolsisoutsidethescopeofthis


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document.YouwillneedtolookuptheIOScommandencapsulation

formoredetails.

3.3ConfiguringCiscoRouting

IProutingisautomaticallyenabledonCiscorouters.Ifithasbeenpreviouslydisabledonyourrouter,youturnitbackoninconfigmodewiththecommandiprouting.

ExampleName(config)#iproutingExampleName(config)#ctrl-Z

ToenableIPv6routing,


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usethecommandipv6unicast-routing.

ExampleName(config)#ipv6unicast-routingExampleName(config)#ctrl-Z

Therearetwomainwaysarouterknowswheretosendpackets.Theadministratorcanassignstaticroutes,ortheroutercanlearnroutesbyemployingadynamicroutingprotocol.

Staticroutesaregenerallyusedinverysimplenetworksorinparticularcasesthatnecessitatetheiruse.


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Tocreateastaticroute,theadministratortellstherouteroperatingsystemthatanynetworktrafficdestinedforaspecifiednetworklayeraddressshouldbeforwardedtoasimiliarlyspecifiednetworklayeraddress.IntheCiscoIOSthisisdonewiththeip

route

andipv6routecommands.

ExampleName#configExampleName(config)#iproute172.16.0.0255.255.255.0192.168.150.1ExampleName(config)#ctrl-ZExampleName#showiproute


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ExampleName#configExampleName(config)#ipv6routefe80::230:1bff:fe80::/64fe80::230:1bff:fe80::1ExampleName(config)#ctrl-ZExampleName#showipv6route

Twothingstobesaidaboutthisexample.First,thepacketdestinationaddressmustincludethesubnetmaskforthatdestinationnetwork.Second,theaddressitistobeforwardedtoisthespecifiedaddresofthenextrouteralongthepathtothedestination.Thisisthemostcommon


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wayofsettingupastaticroute,andtheonlyonethisdocumentcovers.Beaware,however,thatthereareothermethods.

Dynamicroutingprotocols,runningonconnectedrouters,enablethoserouterstoshareroutinginformation.Thisenablesrouterstolearntheroutesavailabletothem.Theadvantageofthismethodisthatroutersareableto


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adjusttochangesinnetworktopologies.Ifarouteisphysicallyremoved,oraneighborroutergoesdown,theroutingprotocolsearchesforanewroute.Routingprotocolscanevendynamicallychoosebetweenpossibleroutesbasedonvariablessuchasnetworkcongestionornetworkreliability.

Therearemanydifferentroutingprotocols,andtheyallusedifferentvariables,


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knownas"metrics,"todecideuponappropriateroutes.Unfortunately,arouterneedstoberunningthesameroutingprotocolsasitsneighbors.Manyrouterscan,however,runmutlipleprotocols.Also,manyprotocolsaredesignedtobeabletopassroutinginformationtootherroutingprotocols.Thisiscalled"redistribution."

Routingprotocolsareacomplextopicandthis


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documentcontainsonlythissuperficialdescriptionofthem.Thereismuchtolearnaboutthem,andtherearemanysourcesofinformationaboutthemavailable.AnexcelentsourceofinformationonthistopicisCisco'swebsite,http://www.cisco.com.

3.4IPv6configurationwithIOS

ThisisaseperatesectionbecauseIPv6isnewtomostpeople,and


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theywillbelookingspecificallyforinformationaboutconfiguringIPv6.ExamplesofconfiguringIPv6areincludedthroughoutthedocument,however,alongsideIPv4.ThatisamoreaccuratereflectionofhowyouwillworkwithIPv6onaday-to-daybasis.OncethenewnessofIPv6passes,itwillbeonemorepieceinthefamiliarpuzzle.

Theimportant


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concepttounderstandwhenconfiguringIPv6isthatIPv4andIPv6existinparrallel.Oneisnotareplacementfortheother,atleastnotinthewayitistreatedbytheoperatingsystem.Atermforthisisdualstack.AninterfacecanhaveanIPv4addressandnoIPv6address.OranIPv6addressand


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noIPv4address.OrbothanIPv4addressandanIPv6address.Examples:

IPv4only

!interfaceFastEthernet0/0ipaddress192.168.1.138255.255.255.0!

IPv6only

!interfaceFastEthernet0/0ipv6addressfe80::230:1bff:fe80::/64ipv6enable!

IPv4andIPv6

!interfaceFastEthernet0/0ipaddress192.168.1.138255.255.255.0ipv6addressfe80::230:1bff:fe80::/64ipv6enable!

Noticethatthereareseperatebutsimiliarcommandsfor


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IPv4andIPv6.ToassignanIPv4address,

ExampleName(config-if)#ipaddress192.168.1.138255.255.255.0

ToassignanIPv6address,

ExampleName(config-if)#ipv6addressfe80::230:1bff:fe80::/64

TherearesomebiggerdifferencesbetweenIPv4andIPv6IOScommands.Forexample,theIPv6equivilantofshowip

arp,isshowipv6

neighbors.

3.5SavingyourCiscoRouterconfiguration

Onceyou


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haveconfiguredroutingontherouter,andyouhaveconfiguredindividualinterfaces,yourroutershouldbecapableofroutingtraffic.Giveitafewmomentstotalktoitsneighbors,thenissuethecommandsshowip

route

andshowip

arp.Thereshouldnowbeentriesinthesetableslearnedfromtheroutingprotocol.

Ifyouturnedthe


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routeroffrightnow,andturneditonagain,youwouldhavetostartconfigurationoveragain.Yourrunningconfigurationisnotsavedtoanyperminentstoragemedia.Youcanseethisconfigurationwiththecommandshowrunning-

config.

ExampleName#showrunning-config

Youdowanttosaveyoursuccessfulrunningconfiguration.Issuethecommandcopyrunning-configstartup-


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config.

ExampleName#copyrunning-configstartup-config

Yourconfigurationisnowsavedtonon-volatileRAM(NVRAM).Issuethecommandshowstartup-

config.

ExampleName#showstartup-config

Nowanytimeyouneedtoreturnyourroutertothatconfiguration,issuethecommandcopystartup-configrunning-

config.

ExampleName#copystartup-configrunning-config

3.6ExampleCiscoRouterconfiguration

Router>enable1.


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Router#config2.Router(config)#hostnameN115-7206

3.

N115-7206(config)#interfaceserial1/1

4.

N115-7206(config-if)ipaddress192.168.155.2255.255.255.0

5.

N115-7206(config-if)ipv6addressfe80::230:1bff:fe80:b8ea/64

6.

N115-7206(config-if)ipv6enable

7.

N115-7206(config-if)noshutdown

8.

N115-7206(config-if)ctrl-z

9.

N115-7206#showinterfaceserial1/1

10.

N115-7206#config11.N115-7206(config)#interfaceethernet2/3

12.

N115-7206(config-if)#ipaddress192.168.150.90255.255.255.0

13.

N115-7206(config-if)#noshutdown

14.

N115-7206(config-if)#ctrl-z

15.

N115-7206#showinterfaceethernet2/3

16.

N115-7206#config17.N115-7206(config)#ipname-server172.16.0.10

18.

N115-7206(config)#ctrl-z19.N115-7206#pingarchie.au

20.

N115-7206#config21.N115-7206(config)#enablesecretpassword

22.

N115-7206(config)#ctrl-z23.N115-7206#copyrunning-config

24.


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startup-configN115-7206#exit25.

4.TroubleshootingyourCiscorouter

Inevitably,therewillbeproblems.Usually,itwillcomeintheformofausernotifyingyouthattheycannotreachacertaindestination,oranydestinattionatall.Youwillneedtobeabletocheckhowtherouterisattemptingtoroute


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traffic,andyoumustbeabletotrackdownthepointoffailure.

Youarealreadyfamiliarwiththeshow

commands,bothspecificcommandsandhowtolearnwhatothershow

commandsareavailable.Someofthemostbasic,mostusefulcommandsyouwillusefortroubleshootingare:

Router#showinterfacesRouter#showipprotocolsRouter#showipv6protocolsRouter#show


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iprouteRouter#showipv6routeRouter#showiparpRouter#showipv6neighbors

4.1Testingconnectivity

Itisverypossiblethatthepointoffailureisnotinyourrouterconfiguration,oratyourrouteratall.Ifyouexamineyourrouter'sconfigurationandoperationandeverythinglooksgood,theproblemmightbebefartheruptheline.Infact,


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itmaybethelineitself,oritcouldbeanotherrouter,whichmayormaynotbeunderyouradministration.

Oneextremelyusefulandsimplediagnostictoolistheping

command.PingisanimplementationoftheIPMessageControlProtocol(ICMP).PingsendsanICMPechorequesttoadestinationIPaddress.Ifthedestination


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machinereceivestherequest,itrespondswithanICMPechoresponse.Thisisaverysimpleexchangethatconsistsof:

Hello,areyoualive?

Yes,Iam.

ExampleName#pingxx.xx.xx.xx

Ifthepingtestissuccessful,youknowthatthedestinationyouarehavingdifficultyreachingisaliveandphysicallyreachable.

Iftherearerouters


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betweenyourrouterandthedestinationyouarehavingdifficultyreaching,theproblemmightbeatoneoftheotherrouters.Evenifyouping

arouteranditresponds,itmighthaveotherinterfacesthataredown,itsroutingtablemaybecorrupted,oranynumberofotherproblemsmayexist.

Toseewherepacketsthat


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leaveyourrouterforaparticulardestinationgo,andhowfar,usethetrace

command.

ExampleName#tracexx.xx.xx.xx

Itmaytakeafewminutesforthisutilitytofinish,sogiveitsometime.Itwilldisplayalistofallthehopsitmakesonthewaytothedestination.

4.2debug

commands

There


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areseveraldebug

commandsprovidedbytheIOS.Thesecommandsarenotcoveredhere.RefertotheCiscowebsiteformoreinformation.

4.3Hardwareandphysicalconnections

Donotoverlookthepossibilitythatthepointoffailureisahardwareorphysicalconnectionfailure.Anynumberofthingscangowrong,fromboardfailuresto


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cutcablestopowerfailures.Thisdocumentwillnotdescribewtroubleshootingtheseproblems,exceptforthesesimplethings.

Checktoseethattherouteristurnedon.Alsomakesurethatnocablesarelooseordamaged.Finally,makesurecablesarepluggedintothecorrectports.Beyondthissimpleadviceyouwillneedtocheckother


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sources.

4.4Outofyourcontrol

Ifthepointoffailureisfartheruptheline,theprolemmightliewithequipmentnotunderyouradministration.Youronlyoptionmightbetocontacttheequipment'sadministrator,notifythemofyourproblem,andaskthemforhelp.Itisinyourinteresttobecourtiousand


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respectful.Theotheradministratorhastheirownproblems,theirownworkloadandtheirownpriorities.Theiragendamightevendirectlyconflictwithyours,suchastheirintentiontochangedynamicroutingprotocols,etc.Youmustworkwiththem,evenifthesituationisfrustrating.Alienatingsomeonewiththepowertoblockimportantroutestoyournetworkisnot


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agoodidea.

5.References

Leinwand,PinskyandCulpepperCiscoRouterConfiguration.Indianapolis,Indiana:CiscoPress,1998.CiscoSystems,Inc.,http://www.cisco.com

6.Moreinformation

CiscoQuickTips

MytutorialonIPsubnetcalculations

CiscoT1LoadBalancing

PDFversionsofthisandotherdocumentsbyJoshGentry

Ads by Google Cisco Router Cisco Server Cisco About Cisco Connect


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Web joshgentry.com

Authored by Josh Gentry

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