网络工程师-5-IOS命令简介

©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Chapter5IOS基本命令©1999,CiscoSystems,Inc.www.cisco.comICND—4-*CiscoIOSSoftware(InternetworkOperatingSystem)CiscoIOSsoftware是Cisco设备的操作系统软件。Slide1of1Purpose:ThisslideintroducetheCiscoIOS.Emphasize:UsethisslideforyourfirstintroductionofCiscoIOSsoftwaretoyourstudents.CiscoIOSsoftwareistheplatformthatdeliversnetworkservicesforthenetworkapplications.ThisIOSsoftwareplatformextendsbeyondtherouters.IOSappliesaswelltoselectedCatalystswitches.Eventually,allCiscoplatformsmaymergetotheCiscoIOSsoftware.Note:TheCat1900and2900xlswitchIOShasacommonlookandfeelliketherouter’sIOS.However,theswitchIOSisnot100%identicaltotherouter’sIOS.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Cisco设备启动 硬件检测 查找并装载IOS 查找并应用配置文件Slide1of1Purpose:ThisslideintroducestartupprocessonCiscoroutersandswitches.Emphasize:Paraphraseorrestatethethreepointsandmakesureyourstudentsfollowthedescription.Thisdescriptionisnecessarytokeepacommonperspectiveofwhatisoccurringonfirsttheswitchandthentherouter;thesethreestepsshouldbeananchortoreturntoasneeded.ThisoverviewofwhathappenswithCisconetworkdevicestartuptransitionstothenexttopic:Wherearethesourcesforconfigurationsoftware?©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Cisco设备配置方式 可以用多种方式配置 配置结果可保存ConsoleportAuxiliaryportInterfacesPCorUnixserverWeborNetworkManagementserverVirtualterminalSlide1of1Purpose:ThisslidedescribethedifferentwaysstudentscanaccesstheCatalystswitchorCiscoroutertocreateanewconfigurationfileoralteranexistingone.Emphasize:Thenetworkdevicecanbeconfiguredfromseverallocations.Afteryoucreatetheinitialconfiguration,youcanconfiguretheportsorinterfacestoenableconfigurationovervirtualterminalsports(VTY).Bothrouterandswitchsupporttelnetaccessasavirtualterminal.Therouterbydefault,supportsvirtualterminals0through4.Thatmeansthatroutercanbeaccessedforconfigurationpurposesfromtheconsoleport,theauxiliaryport,andfiveVTYlinesatthesametime—uptosevenpeoplecanconfiguretherouteratonce.Youshouldcautionstudentsabouttheabovepointandinformthemthatsecurityshouldbestrictlyobservedthroughpasswordprotectiontoavoidunauthorizedaccessoftheconfigurationfiles.AnothercomponentimportanttoconfigurationinthenetworkisaTFTPserver.TheTFTPservercanbeaUNIXorPCworkstationthatactsasacentraldepositoryforfiles.YoucankeepconfigurationfilesontheTFTPserverandthendownloadthemtothedevice.YoucanalsoconfigurethefromanetworkmanagementstationrunningnetworkmanagementsoftwaresuchasCWSI,CiscoWorksorHPOpenView.Beforeyoucanaccessorchangetheconfigurationfromavirtualterminal,TFTPserver,ornetworkmanagementstation,youmusthavethedeviceconfiguredtosupportIPtraffic.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*CiscoIOS用户接口命令行方式可以用命令的简写方式两种主要工作模式用户模式router>特权模式router#CiscoIOSSlide1of1Purpose:ThisslideintroducethetwoIOSEXECmodesontheCat1900switchandrouters.Emphasize:Asyoupresentthis,describethebulletpointsthatcanprepareyourstudentstoworkwiththeCiscoIOSuserinterface.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*用户模式UserMode 有限的命令与能力 提示符hostname>TherearetwomainEXECmodesforenteringcommands.Firstmode:Slide1of1Purpose:ThisslidedescribetheUserEXECmode.Emphasize:PresenttheoperationalaspectsofUserEXECmode.Tellyourstudentsthatthiscommandlevelallowsapersontoaccessonlyalimitedamountofbasicmonitoringcommands.Emphasizethattheyneedtolookcarefullyatthecommandpromptertomakesurethattheyareinanappropriatemodeforthecommandthattheywanttoenterintothenetworkdevice.Ifyoucangetyourclasstolearnthislesson,thiswilleliminate(oratleastreduce)thenumberoftimesthatyouhavetopointoutthatthestudent’slabstepisfailingbecausehe/sheishereinusermoderatherthaninenabledmode.TransitionnexttoanintroductionofPrivileged(orenabled)mode.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*特权模式Privileged(orenabled)Mode 更多的命令，更强的功能 可以进行配置与调试 是进入其他模式的前提---接口、配置、线控、子接口… 提示符hostname#Secondmode(andmostcommonlyused):Slide1of1Purpose:ThisslidedescribethePriviledgedEXECmode.Emphasize:AsyoupresenttheintroductorymaterialonPrivileged(alsocalled“enabled”)mode,emphasizethatthismodeistheentrymodeforalltheotherconfigurationmodes.TellyourstudentsthattheywillneedthismodeforICNDlabsandmostofthenetworkadministrationthattheydobackonthejob.Usetheanalogyof“thepriceofadmission”:Youmusttypeenableandthenpaywiththecorrectenablepassword;otherwise,youdonotgetintothenetworkdevice;youhavetostayoutsideinusermodewhereyoucanonlyseeafewbasicthingsaboutthenetworkdevice.Note:ThisslideendstheintroductorymaterialthatiscommontothenetworkdevicescoveredinICND.TransitionwiththenextslidetomaterialspecifictotheinitialstartupoftheCatalystswitch.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*CiscoRouter的初始化SystemstartuproutinesinitiateroutersoftwareRouterfallsbacktostartupalternativesifneededCheckhardwareFindandloadCiscoIOSsoftwareimageFindandapplyrouterconfigurationinformationLoadBootstrap1. Beforeyoustarttherouter, verifythepower,cabling,and consoleconnection2. Pushthepowerswitchtoon3. Observethebootsequence CiscoIOSsoftwareoutput textontheconsoleSlide1of1Purpose:Thisslidedescribeahighleveloverviewofthestartupsequencesontherouter.Emphasize:ThereisadetailedflowchartthatcoversthisinmuchmoredetailsinChapter6.ConfigregisterisalsocoveredinChapter6.ThestartuproutinesforCiscoIOSsoftwarehavethegoalofstartingrouteroperations.Theroutermustdeliverreliableperformanceconnectingtheusernetworksitwasconfiguredtoserve.Todothis,thestartuproutinesmust:Makesurethattheroutercomesupwithtestedhardware.FindandloadtheCiscoIOSsoftwarethattherouterusesforitsoperatingsystem.Findandapplytheconfigurationstatementsaboutrouter-specificattributes,protocolfunctions,andinterfaceaddresses.Therouterwillmakesurethatitcomesupwithtestedhardware.WhenaCiscorouterpowersup,itperformsapower-upself-test(POST).ThesediagnosticsverifythebasicoperationoftheCPU,memory,andinterfacecircuitry.Afterverifyingthehardwarefunctions,therouterproceedswithsoftwareinitialization.Somestartuproutinesactasfallbackoperationsthatareabletoperformtherouterstartupshouldotherroutinesbeunabletodoso.ThisflexibilityallowsCiscoIOSsoftwaretostartupinavarietyofinitialsituations.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Router启动输出 ---SystemConfigurationDialog---Continuewithconfigurationdialog?[yes/no]:yesAtanypointyoumayenteraquestionmark'?'forhelp.Usectrl-ctoabortconfigurationdialogatanyprompt.Defaultsettingsareinsquarebrackets'[]'.Setupmode没有配置的routerwg_ro_ccon0isnowavailablePressRETURNtogetstarted.User-mode配置过的routerwg_ro_c>ConsoleSlide1of1Purpose:Thisslidedescribethedifferenceoftheconsoleoutputofanunconfiguredrouterversusaconfiguredrouter.Emphasize:Routerhassetupmodetopromptuserforaninitialconfiguration.TheCat1900switchhasnosetupmode,itcomeswithafactorydefaultconfiguration.Thenextseriesofslidesshowsthesetupmodeprompting.Note:Thesetupmodepromptingon12.0isdifferentthanpre-release12.0.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Setup:进入交互式配置过程Router#setup---SystemConfigurationDialog---Continuewithconfigurationdialog?[yes/no]:yAtanypointyoumayenteraquestionmark'?'forhelp.Usectrl-ctoabortconfigurationdialogatanyprompt.Defaultsettingsareinsquarebrackets'[]'.Basicmanagementsetupconfiguresonlyenoughconnectivityformanagementofthesystem,extendedsetupwillaskyoutoconfigureeachinterfaceonthesystemWouldyouliketoenterbasicmanagementsetup?[yes/no]:nSlide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Oneroutineforinitialconfigurationisthesetupmode.Theprimarypurposeofthesetupmodeistorapidlybringupaminimal-featureconfigurationforanyrouterthatcannotfinditsconfigurationfromsomeothersource.Formanyofthepromptsinthesystemconfigurationdialogofthesetupcommandfacility,defaultanswersappearinsquarebrackets([])followingthequestion.PressingtheReturnkeyallowsyoutousethedefaults.Ifthesystemwaspreviouslyconfigured,thedefaultsthatappeararethecurrentlyconfiguredvalues.Ifyouareconfiguringthesystemforthefirsttime,thefactorydefaultsareprovided.Ifthereisnofactorydefault,asinthecaseofpasswords,nothingisdisplayedafterthequestionmark(?).Atthispoint,youcanchoosenottocontinuewiththesystemconfigurationdialogandcanexitbyenteringNoattheprompt.Tobegintheinitialconfigurationprocess,enterYes.YoucanpressCtrl-Ctoterminatetheprocessandstartoveratanytime.Whenyouareusingthecommandformofsetup(Router#setup),Ctrl-CreturnsyoutotheprivilegedEXECprompt(Router#).Ifa“--More--”promptappears,pressthespacebartocontinue.Note:Whenthestudentperformstheroutersetupmodelablater,makesuretheyselect“no”toWouldyouliketoenterbasicmanagementsetup?[yes/no]:©1999,CiscoSystems,Inc.www.cisco.comICND—4-*SetupInterfaceSummaryFirst,wouldyouliketoseethecurrentinterfacesummary?[yes]:InterfaceIP-AddressOK?MethodStatusProtocolBRI0unassignedYESunsetadministrativelydowndownBRI0:1unassignedYESunsetadministrativelydowndownBRI0:2unassignedYESunsetadministrativelydowndownEthernet0unassignedYESunsetadministrativelydowndownSerial0unassignedYESunsetadministrativelydowndownInterfacesfoundduringstartupSlide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:©1999,CiscoSystems,Inc.www.cisco.comICND—4-*SetupGlobalParametersInitialglobalparametersConfiguringglobalparameters:Enterhostname[Router]:wg_ro_cTheenablesecretisapasswordusedtoprotectaccesstoprivilegedEXECandconfigurationmodes.Thispassword,afterentered,becomesencryptedintheconfiguration.Enterenablesecret:ciscoTheenablepasswordisusedwhenyoudonotspecifyanenablesecretpassword,withsomeoldersoftwareversions,andsomebootimages.Enterenablepassword:sanfranThevirtualterminalpasswordisusedtoprotectaccesstotherouteroveranetworkinterface.Entervirtualterminalpassword:sanjoseConfigureSNMPNetworkManagement?[no]:Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Youarepromptedforglobalparametersattheconsole.Youusetheconfigurationvaluesyouhavedeterminedforyourroutertoentertheglobalparametersattheprompts.Thefirstglobalparameterallowsyoutosettherouterhostname.ThishostnamewillprecedetheCiscoIOSpromptersforallconfigurationmodes.Atthefactorytherouternamedefaultisshownbetweenthesquarebracketsas[Router].Usethenextglobalparametersshowntosetthevariouspasswordsusedontherouter.Youmustenteranenablesecretpassword.Whenyouenterastringofpasswordcharactersforthepromptto“Enterenablesecret,”thecharactersareprocessedbyCisco-proprietaryencryption,whichcanenhancethesecurityofthepasswordstring.Wheneveranyoneliststhecontentsoftherouterconfigurationfile,thisenablepasswordappearsasameaninglessstringofcharacters.Setuprecommends,butdoesnotrequire,thattheenablepasswordbedifferentfromtheenablesecretpassword.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*SetupGlobalParameters(cont.)InitialprotocolconfigurationsConfigureLAT?[yes]:nConfigureAppleTalk?[no]:ConfigureDECnet?[no]:ConfigureIP?[yes]:ConfigureIGRProuting?[yes]:nConfigureRIProuting?[no]:ConfigureCLNS?[no]:ConfigureIPX?[no]:ConfigureVines?[no]:ConfigureXNS?[no]:ConfigureApollo?[no]:Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Whenthestudentperformthelablater,makesurethestudentsselect“yes”toConfigureIP?and“no”toallotherprotocols.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*SetupInterfaceParametersBRIinterfaceneedsisdnswitch-typetobeconfiguredValidswitchtypesare:[0]none..........Onlyifyoudon'twanttoconfigureBRI.[1]basic-1tr6....1TR6switchtypeforGermany[2]basic-5ess....AT&T5ESSswitchtypefortheUS/Canada[3]basic-dms100..NorthernDMS-100switchtypeforUS/Canada[4]basic-net3....NET3switchtypeforUKandEurope[5]basic-ni......NationalISDNswitchtype[6]basic-ts013...TS013switchtypeforAustralia[7]ntt...........NTTswitchtypeforJapan[8]vn3...........VN3andVN4switchtypesforFranceChooseISDNBRISwitchType[2]:Configuringinterfaceparameters:DoyouwanttoconfigureBRI0(BRId-channel)interface?[no]:DoyouwanttoconfigureEthernet0interface?[no]:yConfigureIPonthisinterface?[no]:yIPaddressforthisinterface:10.1.1.33Subnetmaskforthisinterface[255.0.0.0]:255.255.255.0ClassAnetworkis10.0.0.0,24subnetbits;maskis/24DoyouwanttoconfigureSerial0interface?[no]:Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Youarepromptedforparametersforeachinstalledinterface.Youusetheconfigurationvaluesyouhavedeterminedforyourinterfacetoentertheinterfaceparametersattheprompts.Lateroninthelab,thestudentswillonlybeconfiguringanIPaddressonE0only.Note:On12.0,thesubnetmaskisactuallyenteredindotteddecimalformat.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*SetupScriptReviewandUseThefollowingconfigurationcommandscriptwascreated:hostnameRouterenablesecret5$1$/CCk$4r7zDwDNeqkxFO.kJxC3G0enablepasswordsanfranlinevty04passwordsanjosenosnmp-server!noappletalkroutingnodecnetroutingiproutingnoclnsroutingnoipxroutingnovinesroutingnoxnsroutingnoapolloroutingisdnswitch-typebasic-5essinterfaceBRI0shutdownnoipaddress!interfaceEthernet0noshutdownipaddress10.1.1.31255.255.255.0nomopenabled!interfaceSerial0shutdownnoipaddress<textomitted>end[0]GototheIOScommandpromptwithoutsavingthisconfig.[1]Returnbacktothesetupwithoutsavingthisconfig.[2]Savethisconfigurationtonvramandexit.Enteryourselection[2]:Slide1of1Purpose:Usethisslidedescribetheoptionsavailablewhenexitingoutofthesetupmodeontherouter.Emphasize:Whenyoucompletetheconfigurationprocess,select[2]tosavetheconfigurationstoNVRAMandmaketheconfigurationactiveinRAM.Ifyouenter[0],theconfigurationisnotsavedtoNVRAMortotheRAM.Note:On12.0,thesearenewoptionstoselectwhenexitingoutofsetupmode.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*用户模式<--->特权模式Consolewg_ro_c>wg_ro_c>enablewg_ro_c#wg_ro_c#disablewg_ro_c>wg_ro_c>logoutwg_ro_ccon0isnowavailablePressRETURNtogetstarted.UsermodepromptPrivilegedmodepromptSlide1of1Purpose:UsethisslidetodiscussthetwoExecmodes.Emphasize:Teachyourstudentstolookforandidentifytheprompterthatindicatesiftheyareinthecorrectmodetoenteragivencommand.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Router用户模式命令可以用省略字输入命令例：en等同与enablewg_ro_c>?Execcommands:access-enableCreateatemporaryAccess-ListentryatmsigExecuteAtmSignallingCommandscdChangecurrentdeviceclearResetfunctionsconnectOpenaterminalconnectiondirListfilesongivendevicedisableTurnoffprivilegedcommandsdisconnectDisconnectanexistingnetworkconnectionenableTurnonprivilegedcommandsexitExitfromtheEXEChelpDescriptionoftheinteractivehelpsystemlatOpenalatconnectionlockLocktheterminalloginLoginasaparticularuserlogoutExitfromtheEXEC--More--Slide1of1Purpose:Emphasize:NoticethattherearemorecommandsavailableontherouterthantheCat1900switch.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Router特权模式命令wg_ro_c#?Execcommands:access-enableCreateatemporaryAccess-Listentryaccess-profileApplyuser-profiletointerfaceaccess-templateCreateatemporaryAccess-ListentrybfeFormanualemergencymodessettingcdChangecurrentdirectoryclearResetfunctionsclockManagethesystemclockconfigureEnterconfigurationmodeconnectOpenaterminalconnectioncopyCopyfromonefiletoanotherdebugDebuggingfunctions(seealso'undebug')deleteDeleteafiledirListfilesonafilesystemdisableTurnoffprivilegedcommandsdisconnectDisconnectanexistingnetworkconnectionenableTurnonprivilegedcommandseraseEraseafilesystemexitExitfromtheEXEChelpDescriptionoftheinteractivehelpsystem--More--可以用TAB键补齐命令Slide1of1Purpose:Emphasize:NoticethattherearemorecommandsavailableontherouterthantheCat1900switch.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Router命令行帮助上下文帮助控制台错误消息Identifyproblemswithroutercommandsincorrectlyenteredsothatyoucanalterorcorrectthem.Allowsrecalloflongorcomplexcommandsorentriesforreentry,review,orcorrection.历史命令缓存Providesalistofcommandsandtheargumentsassociatedwithaspecificcommand.Slide1of1Purpose:Emphasize:Note:TheCat1900hasafixedhistorysizeof10whichcan’tbechanged.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*RouterContext-SensitiveHelpRouter#clokTranslating"CLOK"%Unknowncommandorcomputername,orunabletofindcomputeraddressRouter#cl?clearclockRouter#clock%Incompletecommand.Router#clock?setSetthetimeanddateRouter#clockset%Incompletecommand.Router#<Ctrl-P>clockset?hh:mm:ssCurrentTime Symbolictranslation Commandprompting LastcommandrecallSlide1of1Purpose:Emphasize:Supposeyouwanttosettherouterclock.Ifyoudonotknowthecommand,usecontext-sensitivehelptocheckthesyntaxforsettingtheclock.Thehelpoutputshowsthatthesetkeywordisrequired.Next,checkthesyntaxforenteringthetime.Nowenterthecurrenttimeusinghours,minutes,andseconds,asshown.Thesystemindicatesthatyouneedtoprovideadditionalargumentstocompletethecommand.PressCtrl-P(orUparrow)torepeatthepreviouscommandentryautomatically.Thenaddaspaceandaquestionmark(?)torevealtheadditionalarguments.Nowyoucancompletethecommandentry.Thecaretsymbol(^)andhelpresponseindicateanerror.Tolistthecorrectsyntax,reenterthecommanduptothepointwheretheerroroccurred,andthenenteraquestionmark(?).EntertheyearusingthecorrectsyntaxandpressReturntoexecutethecommand.Notethattheuserinterfaceprovidessyntaxcheckingintheformofanerrorlocationindicator(^).Thecaretsymbolcharacterappearsatthepointinthecommandstringwhereyouhaveenteredanincorrectcommand,keyword,orargument.Theerrorlocationindicatorandinteractivehelpsystemallowyoutofindandcorrectsyntaxerrorseasily.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*RouterContext-SensitiveHelp(cont.)Router#clokTranslating"CLOK"%Unknowncommandorcomputername,orunabletofindcomputeraddressRouter#clearclockRouter#%Incompletecommand.Router#setSetthetimeanddateRouter#%Incompletecommand.Router#hh:mm:ssCurrentTimeRouter#clockset19:56:00%Incompletecommand.Router#clockset19:56:00?<1-31>DayofthemonthMONTHMonthoftheyearRouter#clockset19:56:00048^%Invalidinputdetectedatthe'^'markerRouter#clockset19:56:0004August%Incompletecommand.Router#clockset19:56:0004August?<1993-2035>Year Commandprompting Syntaxchecking CommandpromptingSlide1of1Purpose:Emphasize:©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令Router>ShapethefutureofinternetworkingbycreatingunprecedShapethefutureofinternetworkingbycreatingunprecedentedvalueforcustomers,employees,andpartners.Slide1of9Purpose:ThisslideexplainhowtousetheeditingcapabilitiesofCiscoIOSsoftware. Emphasize:Layer1—Somecommandscanbelongerthanthenumberofcharactersavailableonthescreenaftertheprompt.Theuserinterfacenowsupportsautomaticscrollingoflonglines.Noticethatwehaverunoutofroomonthisline.Thelinewillscrollovertenspacesatatimeinordertoallowlongerlines. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令Router>$futureofinternetworkingbycreatingunprecedentedop (Automaticscrollingoflonglines). Slide2of9Purpose:Emphasize:Layer2—Hereisthesamelineafterithasstartedscrolling.Noticethatadollarsign($)appearsatthebeginningofthelineaftertheprompt.Thisspecialcharacterindicatesthatmorecharacterstotheleftarenotshown.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令Router>Shapethevalueofinternetworkingbycreatingunpreced (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. Slide3of9Purpose:Emphasize:Layer3—Theinterfaceimplementssomesophisticatedmotioncommandsforworkingwiththescrolledline.Forexample,ifyouwanttoseethebeginningoftheline,pressCtrl-Atoplacethecursoronthefirstcharacterofaline.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令Router>$valueforcustomers,employees,andpartners. (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. Slide4of9Purpose:Emphasize:Layer4—Ctrl-Emovestotheendoftheline.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令 (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. <Esc-B> Movebackoneword. Router>$valueforcustomers,employees,andpartners.Slide5of9Purpose:Emphasize:Layer5—Esc-Bmovestothebeginningofthepreviousword.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令 (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. <Esc-B> Movebackoneword. <Ctrl-F> Moveforwardonecharacter. Router>$valueforcustomers,employees,andpartners.Slide6of9Purpose:Emphasize:Layer6—Ctrl-Fmovesforwardonecharacter.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令 (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. <Esc-B> Movebackoneword. <Ctrl-F> Moveforwardonecharacter. <Ctrl-B> Movebackonecharacter. Router>$valueforcustomers,employees,andpartners.Slide7of9Purpose:Emphasize:Layer7—Ctrl-Bmovesbackonecharacter.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令 (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. <Esc-B> Movebackoneword. <Ctrl-F> Moveforwardonecharacter. <Ctrl-B> Movebackonecharacter. <Esc-F> Moveforwardoneword. Router>$valueforcustomers,employees,andpartners.Slide8of9Purpose:Emphasize:Layer8—Esc-Fmovesforwardoneword.UsetheDeleteandBackspacekeystoremoveandchangecharactersinthecommandline.Ctrl-Uerasesthetextfromthebeginningofthecommandline.TousetheCtrl+keycombination,holddowntheCtrlkeywhilepressingthedesiredletterkey.TousetheEsc+keycombination,pressandreleasetheEsckeythenpressthedesiredletterkey.Toturnofftheeditmode,entertheterminalnoeditcommand.Editmodeisenabledbydefault.Usethe“showterminal”execcommandtoseeifeditmodeisenabledornot.Note:Theterminaleditingmodecan’tbedisabledontheCat1900.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令 (Automaticscrollingoflonglines). <Ctrl-A> Movetothebeginningofthecommandline. <Ctrl-E> Movetotheendofthecommandline. <Esc-B> Movebackoneword. <Ctrl-F> Moveforwardonecharacter. <Ctrl-B> Movebackonecharacter. <Esc-F> Moveforwardoneword.<Ctrl-D>Deleteasinglecharacter. Router>$valueforcustomers,employees,andpartners.Slide9of9Purpose:Emphasize:Layer9—Ctrl-Ddeletesasinglecharacter.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*命令行编辑命令—历史命令Ctrl-PorUparrowLast(previous)commandrecallCtrl-NorDownarrowMorerecentcommandrecallRouter>showhistoryShowcommandbuffercontentsRouter>terminalhistorysizelinesSetsessioncommandbuffersizeSlide1of1Purpose:Emphasize:Theuserinterfaceprovidesahistoryorrecordofcommandsyouhaveentered.Thisfeatureisparticularlyusefulforrecallinglongorcomplexcommandsorentries.Withthecommandhistoryfeature,youcancompletethefollowingtasks:SetthecommandhistorybuffersizeRecallcommandsDisablethecommandhistoryfeatureBydefault,commandhistoryisenabledandthesystemrecords10commandlinesinitshistorybuffer.Tochangethenumberofcommandlinesthesystemwillrecordduringthecurrentterminalsession,usetheterminalhistorysizeorhistorysizecommand.Themaximumnumberofcommandsis256.Torecallcommandsinthehistorybufferbeginningwiththemostrecentcommand,pressCtrl-PortheUparrowkey.Repeatthekeysequencetorecallsuccessivelyoldercommands.ToreturntomorerecentcommandsinthehistorybufferafterrecallingcommandswithCtrl-PortheUparrow,pressCtrl-NortheDownarrow.Repeatthekeysequencetorecallsuccessivelymorerecentcommands.Onceyouentertheuniquecharactersforacommand,presstheTabkeyandtheinterfacewillfinishtheentryforyou.Onmostlaptopcomputersyoumayalsohaveadditionalselectandcopyfacilitiesavailable.Copyapreviouscommandstring,thenpasteorinsertitasyourcurrent.Note:TheCat1900hasafixedhistorysizeof10whichcan’tbechanged.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*showversion命令wg_ro_a#showversionCiscoInternetworkOperatingSystemSoftwareIOS(tm)2500Software(C2500-JS-L),Version12.0(3),RELEASESOFTWARE(fc1)Copyright(c)1986-1999byciscoSystems,Inc.CompiledMon08-Feb-9918:18byphanguyeImagetext-base:0x03050C84,data-base:0x00001000ROM:SystemBootstrap,Version11.0(10c),SOFTWAREBOOTFLASH:3000BootstrapSoftware(IGS-BOOT-R),Version11.0(10c),RELEASESOFTWARE(fc1)wg_ro_auptimeis20minutesSystemrestartedbyreloadSystemimagefileis"flash:c2500-js-l_120-3.bin"(outputomitted)--More--Configurationregisteris0x2102注意当前配置寄存器的值Slide1of1Purpose:Thisslidepresentstheshowversioncommand.Emphasize:Pointoutthatthiscommandisusefulwhentroubleshootingproblemsbecauseitgivestheversionsofthevarioussoftwarecomponentsandfiles.Italsodisplayshowlongtherouterhasbeeninoperationandwhereitobtainedtheimagefile.ConfigregisterisdiscussedinChapter6. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*查看配置信息ConsoleIOSSetuputilityshowstartup-configshowrunning-configSetupsavestheconfigurationtoNVRAMConfigConfigRAMNVRAMSlide1of1Purpose:Emphasize:Whenyouexitthesetupmode,theconfigurationcanbesavedtoRAMandNVRAMatthesametime.Note:TheCat1900hasno“showstart”command.ItautomaticallysavestherunningconfigurationtoNVRAM.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*showrunningandshowstartupCommandswg_ro_c#showstartup-configUsing1359outof32762bytes!version12.0! --More--wg_ro_c#showrunning-configBuildingconfiguration...Currentconfiguration:!version12.0! --More--InNVRAMInRAMDisplaycurrentandsavedconfigurationSlide1of1Purpose:Thisslideshowstheformatandoutputoftheshowrunning-configandshowstartup-configcommands,whichdisplaytheactiveandbackupconfigurationfiles,respectively.Emphasize:Weputthesetwocommandsonthesamepagebecauseitiseasytoconfusethetwo.Theshowrunning-configcommanddisplaystheconfigurationinformationinmemory,whiletheshowstartup-configcommanddisplaysthebackupfile.Ofteninclasssomeonewillentercommandsandthensaythattherouterdidnotacceptthem.Thisscenariomightindicatethatthepersonenteredthecommandstomodifytheconfigurationinformationinmemory,andthenenteredashowstartup-config(showconfig)tolookatthebackupfilethathasnotyetbeenupdatedtoreflectthechanges.Youmustuseanothercommandtoupdatethebackupfile.Defaultparametersdonotdisplayintherunningconfiguration. InCiscoIOSRelease10.2andearlier,thecommandwriteterminalshowstherunningconfiguration,andthecommandshowconfigshowsthestartupconfiguration.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Router各种模式UsermodePrivilegedmodeGlobalconfigurationmodeRouter(config)#Router>enableRouter#configtermExitCtrl-Z(end)ConfigurationModePromptInterface Router(config-if)#Subinterface Router(config-subif)#Controller Router(config-controller)#Line Router(config-line)#Router Router(config-router)#IPXrouter Router(config-ipx-router)#Slide1of1Purpose:Emphasize:Hereisalistofsomeoftheconfigurationmodesavailable.Foracompletelistoftherouterconfigurationmodes,refertotheCiscoDocumentationCD-ROM.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*保存当前模式wg_ro_c#wg_ro_c#copyrunning-configstartup-configDestinationfilename[startup-config]?Buildingconfiguration…wg_ro_c#CopythecurrentconfigurationtoNVRAMSlide1of1Purpose:Emphasize:CopyingtoNVRAMoverwritesthecontentsinNVRAM.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*设置Router标识RouterNameRouter(config)#hostnamewg_ro_cwg_ro_c(config)#MessageoftheDayBannerwg_ro_c(config)#bannermotd# AccountingDepartmentYouhaveenteredasecuredsystem.Authorizedaccessonly!#Slide1of2Purpose:Thispageexplainshowtoidentifyroutersonthenetwork.Emphasize:Layer1—Tomakeconfiguringandmaintaininganetworkeasier,severalfeaturesproviderecordinganddescriptiveinformationintheconfigurationoftherouter.Thefirstisthehostname,whichissimplyanamebywhichthisrouterisknowninthenetwork.Whenyoulogintoarouter,thehostnameisdisplayedintheprompt.Thisfeatureisveryconvenientwhenyouareremotelyconfiguringrouters,becauseitisaquickreminderofwhichrouteryouareaccessing.Thisnameisalsousedwhenaddressingroutersacrossthenetwork.Hereisanexamplebanner.Themotdkeywordstandsfor“messageoftheday.”Thepoundsign(#)aftermotdisadelimiter.Thebannermessagebeginsafterthischaracterandendswhenthischaracternextappearsinthetext.Youcanhavemanylines—afullscreen—andifyouknowhowtoenterthespecialcommandsforVTextendedmodes,youcangetelongatedandhighlightedcharactersinyourbanner.Ifyouarenotinasecurenetwork,abannerisagoodplacetoputnetworkmaintenanceinformationsuchasthedescriptionofuserswhodependonthisrouterandwheretherouterislocated.Rememberthatanyonecanseethisinformation.Youshouldbeverycarefulaboutthewordingofyourbannermessage.Includingtheword“Welcome”inabannerisanexplicitinvitationtoanyone,includinghackers,toenteryournetwork.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*设置Router标识设置本地Router标识与接口描述信息RouterNameRouter(config)#hostnamewg_ro_cwg_ro_c(config)#MessageoftheDayBannerwg_ro_c(config)#bannermotd# AccountingDepartmentYouhaveenteredasecuredsystem.Authorizedaccessonly!#InterfaceDescriptionwg_ro_c(config)#interfaceethernet0wg_ro_c(config-if)#descriptionEngineeringLAN,Bldg.18Slide2of2Purpose:Emphasize:Layer2—Theinterfacedescriptioncommandallowsyoutoenteraone-linedescriptivestatementforeachinterface.Thisdescriptionisdisplayedintheoutputfromtheshowinterfacescommandandappearsintheshowrunning-configandshowstartup-configlistings. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*设置控制台口令Router(config)#lineconsole0Router(config-line)#loginRouter(config-line)#passwordciscoConsolePasswordVirtualTerminalPasswordRouter(config)#linevty04Router(config-line)#loginRouter(config-line)#passwordsanjoseSlide1of2Purpose:Thispageexplainshowtoconfigurepasswords. Emphasize:Layer1—Theconsolepasswordissetindependentlyfromotherlinepasswords,suchasvirtualterminalpasswords.Ifyourconsoleisinyourofficeunderlockandkey,thenyoumaynotneedaconsolepassword;justpressReturnandyouwillbeinusermodeautomatically.However,ifyourconsoleisoutwhereanyonehasaccesstoit,youmightwanttoputapasswordontheconsoleline.Passwordsarecase-sensitivesobeawareiftheCapsLockkeyisonoroff.Thevirtualterminalpasswordmustbesetforremoteconfigurationsupport.Telnetrequiresapasswordcheck.Thenumbers0and4arearange—thatis,VTYlineszerothroughfour,whichequalsfivelines.Youmightwanttosetoneofthevirtualterminalpasswordstobeunique.Thissettingisusuallydoneinalargenetworkwithmanynetworkadministrators.YousetfouridenticalVTYpasswordssothateveryonecangetintotherouter,andsetoneVTYpasswordtosomethingelse.Thisway,ifacatastrophicproblemoccursonthenetworkandallcommonVTYlinesareinuse,theoneuniquelineisinreserveforrecovery.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*设置特权模式口令Router(config)#lineconsole0Router(config-line)#loginRouter(config-line)#passwordciscoConsolePasswordVirtualTerminalPasswordRouter(config)#linevty04Router(config-line)#loginRouter(config-line)#passwordsanjoseEnablePasswordRouter(config)#enablepasswordciscoSecretPasswordRouter(config)#enablesecretsanfran Slide2of2Purpose:Emphasize:Therouterhasoneenablepassword.Rememberthatthisisyouronlyprotection.Whoeverownsthispasswordcandoanythingwiththerouter,sobecarefulaboutcommunicatingthispasswordtoothers.Toprovideanadditionallayerofsecurity,particularlyforpasswordsthatcrossthenetworkorarestoredonaTFTPserver,youcanuseeithertheenablepasswordorenablesecretcommands.Bothcommandsaccomplishthesamething;thatis,theyallowyoutoestablishanencryptedpasswordthatusersmustentertoaccessenablemode(thedefault),oranyprivilegelevelyouspecify.Ciscorecommendsthatyouusetheenablesecretcommandbecauseitusesanimprovedencryptionalgorithm.UsetheenablepasswordcommandonlyifyoubootanolderimageoftheCiscoIOSsoftware,orifyoubootolderbootROMsthatdonotrecognizetheenablesecretcommand.Ifyouconfiguretheenablesecretpassword,itisusedinsteadoftheenablepassword,notinadditiontoit.Ciscosupportspasswordencryption.Turnonpasswordencryptionusingtheservicepassword-encryptioncommand.Thenenterthedesiredpasswordsforencryption.Immediately,onthenextline,enterthenoservicepassword-encryption.Onlythosepasswordsthataresetbetweenthetwocommandswillbeencrypted.Ifyouenterservicepassword-encryptionandthenpressCtrl-Ztoexit,allpasswordswillbeencrypted.Note:Passwordrecoveryisnotcoveredinthecoursematerials.ReferthestudentstotheIMCRclass. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*其它控制台命令Router(config)#lineconsole0Router(config-line)#exec-timeout00Router(config)#lineconsole0Router(config-line)#loggingsynchronous 防止本地会话连接断开 设置输出显示同步Slide1of1Purpose:Emphasize:Ifthestudententers“noexec”bymistake,theconsoleportExecmodewillbedisabledonceloggedoutofthecurrentsession.Ifthishappen,youhavetobreakintototherouterusingROMmonitortorecover(settheconfigregto0x2142soitwillignoreNVRAM).©1999,CiscoSystems,Inc.www.cisco.comICND—4-*配置接口Router(config)#interfacetypenumberRouter(config-if)# typeincludesserial,ethernet,tokenring,fddi,hssi,loopback,dialer,null,async,atm,bri,andtunnel numberisusedtoidentifyindividualinterfaces QuitfromcurrentinterfaceconfigurationmodeRouter(config)#interfacetypeslot/portRouter(config-if)# FormodularroutersSlide1of1Purpose:Thispageshowstheinterfaceconfigurationmode.Emphasize:Thetoplineistheformatofthecommandusedinfixed-portrouters.Thetypefieldshowstheinterfacetype,whichcanbeEthernet,TokenRing,oranotherinterface.Thenumberfieldisthenumberoftheinterface.Forexample,iftherouterhastwoEthernetinterfaces,andoneisknownasEthernet0,theotherwillbecalledEthernet1.ThesecondcommandisusedontheCisco7000and7200seriesrouters,whichcanacceptmultipleinterfacecardswithmultipleportsoneachcard.Inthiscase,thefirstnumberisthenumberofthecard,orslotnumber.Thesecondnumberistheportonthecard.Forexample,onthesecondinterfacecard,thefirstEthernetinterfaceisspecifiedasEthernet2/0.IfyouhaveCisco7000and7500seriesrouterswithVIPcards,youdefineaninterfaceinthebyslot,portadapters,andportnumbers.Portadaptersareassignedeithera0or1number.Usetheexitcommandtoleavethecurrentconfigurationmode. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*配置串口EnterglobalconfigurationmodeRouter(config)#interfaceserial0Router(config-if)#Router#configuretermRouter(config)#SpecifyinterfaceSlide1of2Purpose:Thispageshowsexamplesofthecommandsusedtoconfigureaserialinterface. Emphasize:Layer1—Inthisexample,weareconfiguringtheserialinterfacefromtheconsoleport.Theconfigureterminalcommandputsusinglobalconfigurationmode.Onceinglobalconfigurationmode,youmustidentifythespecificinterfaceagainstwhichyouwillbeissuingcommands.Noticeafteryouenterthespecificinterfacecommandthatthepromptnowindicatesyouareininterfaceconfigurationmode.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*配置串口EnterglobalconfigurationmodeRouter(config-if)#clockrate64000Router(config-if)#Router(config)#interfaceserial0Router(config-if)#Router#configuretermRouter(config)#Router(config-if)#bandwidth64Router(config-if)#exitRouter(config)#exitRouter#SpecifyinterfaceSetclockrate(onDCEinterfacesonly)Setbandwidth(recommended)Slide2of2Purpose:Thisslideshowstwoconfigurationparametersfortheserialinterface.Emphasize:Layer2—Issuetheclockratecommandwiththedesiredspeed.Onseriallinks,onesideofthelinkactsasdatacommunicationsequipment(DCE)andtheothersideofthelinkactsasthedataterminalequipment(DTE).Bydefault,CiscoroutersareDTEdevices,butcanbeconfiguredasDCEdevices.Ina“back-to-back”cableconfigurationwhereamodemisnotused,oneendmustprovidetheclockingsignal.YoumustspecifyclockratefortheDCEinterfaceendinthistypeofenvironment.Desiredclockrateisinbitspersecond.Besuretotypethecompleteclockspeed.Forexample,aclockrateof56000cannotbeabbreviatedto56.IfyouareusinganRS232cable,usingahighclockratemaycauseerrorsontheline.Usetheshowcontrollerserial0commandtoverifyiftherouterhasaDCEorDTEcableconnectedtoit.Note,therouteronlyreadstheDCE/DTEcableinformationatstartup.Thebandwidthcommandoverridesthedefaultbandwidth(1.544M).TheBandwidthparameter(inkbps)isusedtocalculatestatisticlikeloadanditisusedbyroutingprotocolssuchasIGRP.WewilllearnmoreaboutroutingprotocolsinChapter9.ToreturntoprivilegedEXECmode,typeexituntiltheprivilegedEXECpromptappears.Note:Inthelab,thecorerouterhastheDCEcablesandtheworkgrouprouterhastheDTEcable.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*验证串口配置Router#showinterfaceserial0Serial0isup,lineprotocolisupHardwareisHD64570Internetaddressis10.140.4.2/24MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)Lastinput00:00:09,output00:00:04,outputhangneverLastclearingof"showinterface"countersneverInputqueue:0/75/0(size/max/drops);Totaloutputdrops:0Queueingstrategy:weightedfairOutputqueue:0/1000/64/0(size/maxtotal/threshold/drops)Conversations0/1/256(active/maxactive/maxtotal)ReservedConversations0/0(allocated/maxallocated)5minuteinputrate0bits/sec,0packets/sec5minuteoutputrate0bits/sec,0packets/sec(outputomitted)Slide1of1Purpose:Thisslideshowsyouhowtoverifythechangesyoumaketoaninterface.Emphasize:Noticethebandwidthhasbeenchangedto64Kfromthedefaultof1.544M.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*启用、禁用接口Router#configuretermRouter(config)#interfaceserial0Router(config-if)#noshutdown%LINK-3-UPDOWN:InterfaceSeria0,changedstatetoup%LINEPROTO-5-UPDOWN:LineProtocolonInterfaceSerial0,changedstatetoupEnablesaninterfacethatisadministrativelyshutdownRouter#configuretermRouter(config)#interfaceserial0Router(config-if)#shutdown%LINK-5-CHANGED:InterfaceSerial0,changedstatetoadministrativelydown%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial0,changedstatetodownAdministrativelyturnsoffaninterfaceSlide1of1Purpose:Emphasize:Cat1900switchalsousesthe“shut”and“noshut”command.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Routershowinterfaces命令Router#showinterfacesEthernet0isup,lineprotocolisupHardwareisLance,addressis00e0.1e5d.ae2f(bia00e0.1e5d.ae2f)Internetaddressis10.1.1.11/24MTU1500bytes,BW10000Kbit,DLY1000usec,rely255/255,load1/255EncapsulationARPA,loopbacknotset,keepaliveset(10sec)ARPtype:ARPA,ARPTimeout04:00:00Lastinput00:00:07,output00:00:08,outputhangneverLastclearingof"showinterface"countersneverQueueingstrategy:fifoOutputqueue0/40,0drops;inputqueue0/75,0drops5minuteinputrate0bits/sec,0packets/sec5minuteoutputrate0bits/sec,0packets/sec81833packetsinput,27556491bytes,0nobufferReceived42308broadcasts,0runts,0giants,0throttles1inputerrors,0CRC,0frame,0overrun,1ignored,0abort0inputpacketswithdribbleconditiondetected55794packetsoutput,3929696bytes,0underruns0outputerrors,0collisions,1interfaceresets0babbles,0latecollision,4deferred0lostcarrier,0nocarrier0outputbufferfailures,0outputbuffersswappedoutSlide1of1Purpose:Thisslidepresentstheshowinterfacescommand,whichindicateswhetherthenetworkisoperatingatthephysicalanddatalinklayers.Thecommandoutputisinterpretedlaterinthischapter.Emphasize:Thetoplineoftheoutputtellsusthatthelineisup.Afewlinesdown,theoutputprovidestheIPaddress,andbelowthatsomecharacteristicslikeBWforbandwidth;DLYfordelay.Onthenextlinedown,wefindencapsulationtype“ARPA”.ARPAmeansEthernetII,whichisthedefaultIPencapsulationtypeforethernetinterfacesonCiscorouters.Aruntisanethernetframethatistoosmalltobelegal(lessthan64bytes),andagiantisanethernetframethatistoobig(greaterthan1518bytes). ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*各种接口状态Router#showinterfacesserial1Serial1isup,lineprotocolisupHardwareisHD64570Description:64KbLinetoSanJose::::::::::::::::::Operational..................Connectionproblem...Interfaceproblem........Disabled......................Serial1isup,lineprotocolisupSerial1isup,lineprotocolisdownSerial1isdown,lineprotocolisdownSerial1isadministrativelydown,lineprotocolisdownKeepalivesCarrierDetectSlide1of1Purpose:ThisslideexplainshowtointerprettheshowinterfacesserialcommandoutputEmphasize:.Theshowinterfacesserialcommandoutputindicatesthattheserialinterfaceisupandthelineprotocolisup.ThefirstparameterreferstothehardwarelayerandessentiallyreflectswhethertheinterfaceisreceivingtheCarrierDetectsignalfromtheotherend.Thesecondparameterreferstothedatalinklayer.Thisparameterreflectswhetherthedatalinklayerprotocolkeepalivesarebeingreceived.Ifboththeinterfaceandthelineprotocolareup,theconnectionisoperational.Ifthehardwareisupandthelineprotocolisdown,aconnectionproblemexistsuchasnoclocking,wrongencapsulationtype,ornokeepalives.Ifboththelineprotocolandtheinterfacearedown,acablemightneverhavebeenattachedtotherouter.Ontheserialcable,youcanpluginthecableupsidedowncausingthepinsontheserialcabletobreak.Thereisonemorepossibility.Iftheinformationsays“administrativelydown,”youhavemanuallydisabled(shut)theinterface.Ciscooffersahardwareclass(IMCR)thatdiscussestherouterhardwareinmoredetail. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*串口showcontroller命令Router#showcontrollerserial0HDunit0,idb=0x121C04,driverstructureat0x127078buffersize1524HDunit0,V.35DTEcable . . .显示V.35线缆类型，判断DCE、DTE设备DCE设备要提供时钟速率#ClockRate64000Slide1of1Purpose:Emphasize:Thiscommandrequiresaspacebetweentheword“serial”andtheinterfacenumber.Therouteronlychecksforthecabletypeatpowerup.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*为交换机配置IP地址 指定IP地址及掩码Switch(config)#ipaddressip-addresssubnet-maskSwitch(config)#ipdefault-gatewayip-address 指定缺省网关Purpose:ThisfigureshowscommandsusedtoconfigureIPaddressesonaCatalyst1900seriesswitch.Emphasize:TheIPaddressonaswitchistypicallyassignedgloballytothedevice.Onarouter,eachinterfacehasauniqueaddress.Theipdefault-gatewaycommandspecifiesadefaultgatewaytotherouter. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*为路由器配置IP地址指定IP地址及掩码Router(config-if)#ipaddressip-addresssubnet-maskPurpose:ThisfigureshowscommandsusedtoconfigureIPaddressesonarouter.Emphasize:TheIPaddressonaswitchistypicallyassignedgloballytothedevice.Onarouter,eachinterfacehasauniqueaddress. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*为路由器配置IP地址Router(config-line)#ipnetmask-format{bitcount|decimal|hexadecimal} 设置网络掩码显示格式（长期）Router#termipnetmask-format{bitcount|decimal|hexadecimal} 设置网络掩码显示格式（暂时）Purpose:ThisfigureshowsoptionalIPaddressformatcommandsusedtodisplayIPaddressesonarouter.Emphasize:Thecommandspresentedarefordisplaypurposesonly.Whenconfiguringarouter,youmuststillusetherequiredconfigurationformat.Forexample,whenconfiguringanIPaddressonaninterface,youmustconfigurethesubnetmaskindotteddecimalformat. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*配置路由器静态名字解析 定义静态名字解析Router(config)#iphostname[tcp-port-number]address[address]iphostNorine172.16.3.1192.168.3.1iphostRoger172.16.4.3Purpose:ThisfigureshowshowtheiphostcommandisusedtomapanIPaddresstoaspecifichostname. Emphasize:Describetheiphostcommand. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*配置路由使用名字服务器 指定名字服务器Router(config)#ipname-serverserver-address1[[server-address2]...[server-address6]]DNSServerPurpose:Thisfigureshowscommandsusedtoconfigurenameservers. Emphasize:Describetheipname-servercommand. ExplainDomainNameSystem(DNS)andhowitworks.DNSisahostsystemusedinthenetworkfortranslatingnamesofnetworknodesintoaddresses.©1999,CiscoSystems,Inc.www.cisco.comICND—4-*启动或关闭自动名字解析缺省启动Router(config)#ipdomain-lookupRouter(config)#endRouter#patTranslating”pat"...domainserver(255.255.255.255)%Unknowncommandorcomputername,orunabletofindcomputeraddressRouter#configtRouter(config)#noipdomain-lookupRouter(config)#endRouter#patTranslating”pat"%Unknowncommandorcomputername,orunabletofindcomputeraddressRouter#Purpose:ThisfigureshowscommandsusedtoenabletheroutertouseDNS.Emphasize:Describethecommands. Ifthestudentshaveaccesstoconsoleterminals,youmayhavethementerthenoipdomain-lookupcommandnow.HavingDNSserveronbydefaultwillcausedelaysinlabsbecause,whenthestudentstypeaninvalidcommand,thedefaultwillbetolookforadomainnameservertointerpretthatcommand. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*显示名字缓存Router#showhostsDefaultdomainisnotsetName/addresslookupusesdomainserviceNameserversare255.255.255.255HostFlagsAgeTypeAddress(es)Norine(perm,OK)0IP172.16.100.100Roger(perm,OK)0IP172.16.100.101Frank(perm,OK)0IP172.16.200.200Bob(perm,OK)0IP172.16.200.201ShowsthehosttablePurpose:Thisfigureshowscommandsusedtodisplaythecachedlistofhostnames.Emphasize:Describetheshowhostscommandoutput. ©1999,CiscoSystems,Inc.www.cisco.comICND—4-*Slide1of1Purpose:ThisslideintroducetheCiscoIOS.Emphasize:UsethisslideforyourfirstintroductionofCiscoIOSsoftwaretoyourstudents.CiscoIOSsoftwareistheplatformthatdeliversnetworkservicesforthenetworkapplications.ThisIOSsoftwareplatformextendsbeyondtherouters.IOSappliesaswelltoselectedCatalystswitches.Eventually,allCiscoplatformsmaymergetotheCiscoIOSsoftware.Note:TheCat1900and2900xlswitchIOShasacommonlookandfeelliketherouter’sIOS.However,theswitchIOSisnot100%identicaltotherouter’sIOS.Slide1of1Purpose:ThisslideintroducestartupprocessonCiscoroutersandswitches.Emphasize:Paraphraseorrestatethethreepointsandmakesureyourstudentsfollowthedescription.Thisdescriptionisnecessarytokeepacommonperspectiveofwhatisoccurringonfirsttheswitchandthentherouter;thesethreestepsshouldbeananchortoreturntoasneeded.ThisoverviewofwhathappenswithCisconetworkdevicestartuptransitionstothenexttopic:Wherearethesourcesforconfigurationsoftware?Slide1of1Purpose:ThisslidedescribethedifferentwaysstudentscanaccesstheCatalystswitchorCiscoroutertocreateanewconfigurationfileoralteranexistingone.Emphasize:Thenetworkdevicecanbeconfiguredfromseverallocations.Afteryoucreatetheinitialconfiguration,youcanconfiguretheportsorinterfacestoenableconfigurationovervirtualterminalsports(VTY).Bothrouterandswitchsupporttelnetaccessasavirtualterminal.Therouterbydefault,supportsvirtualterminals0through4.Thatmeansthatroutercanbeaccessedforconfigurationpurposesfromtheconsoleport,theauxiliaryport,andfiveVTYlinesatthesametime—uptosevenpeoplecanconfiguretherouteratonce.Youshouldcautionstudentsabouttheabovepointandinformthemthatsecurityshouldbestrictlyobservedthroughpasswordprotectiontoavoidunauthorizedaccessoftheconfigurationfiles.AnothercomponentimportanttoconfigurationinthenetworkisaTFTPserver.TheTFTPservercanbeaUNIXorPCworkstationthatactsasacentraldepositoryforfiles.YoucankeepconfigurationfilesontheTFTPserverandthendownloadthemtothedevice.YoucanalsoconfigurethefromanetworkmanagementstationrunningnetworkmanagementsoftwaresuchasCWSI,CiscoWorksorHPOpenView.Beforeyoucanaccessorchangetheconfigurationfromavirtualterminal,TFTPserver,ornetworkmanagementstation,youmusthavethedeviceconfiguredtosupportIPtraffic.Slide1of1Purpose:ThisslideintroducethetwoIOSEXECmodesontheCat1900switchandrouters.Emphasize:Asyoupresentthis,describethebulletpointsthatcanprepareyourstudentstoworkwiththeCiscoIOSuserinterface.Slide1of1Purpose:ThisslidedescribetheUserEXECmode.Emphasize:PresenttheoperationalaspectsofUserEXECmode.Tellyourstudentsthatthiscommandlevelallowsapersontoaccessonlyalimitedamountofbasicmonitoringcommands.Emphasizethattheyneedtolookcarefullyatthecommandpromptertomakesurethattheyareinanappropriatemodeforthecommandthattheywanttoenterintothenetworkdevice.Ifyoucangetyourclasstolearnthislesson,thiswilleliminate(oratleastreduce)thenumberoftimesthatyouhavetopointoutthatthestudent’slabstepisfailingbecausehe/sheishereinusermoderatherthaninenabledmode.TransitionnexttoanintroductionofPrivileged(orenabled)mode.Slide1of1Purpose:ThisslidedescribethePriviledgedEXECmode.Emphasize:AsyoupresenttheintroductorymaterialonPrivileged(alsocalled“enabled”)mode,emphasizethatthismodeistheentrymodeforalltheotherconfigurationmodes.TellyourstudentsthattheywillneedthismodeforICNDlabsandmostofthenetworkadministrationthattheydobackonthejob.Usetheanalogyof“thepriceofadmission”:Youmusttypeenableandthenpaywiththecorrectenablepassword;otherwise,youdonotgetintothenetworkdevice;youhavetostayoutsideinusermodewhereyoucanonlyseeafewbasicthingsaboutthenetworkdevice.Note:ThisslideendstheintroductorymaterialthatiscommontothenetworkdevicescoveredinICND.TransitionwiththenextslidetomaterialspecifictotheinitialstartupoftheCatalystswitch.Slide1of1Purpose:Thisslidedescribeahighleveloverviewofthestartupsequencesontherouter.Emphasize:ThereisadetailedflowchartthatcoversthisinmuchmoredetailsinChapter6.ConfigregisterisalsocoveredinChapter6.ThestartuproutinesforCiscoIOSsoftwarehavethegoalofstartingrouteroperations.Theroutermustdeliverreliableperformanceconnectingtheusernetworksitwasconfiguredtoserve.Todothis,thestartuproutinesmust:Makesurethattheroutercomesupwithtestedhardware.FindandloadtheCiscoIOSsoftwarethattherouterusesforitsoperatingsystem.Findandapplytheconfigurationstatementsaboutrouter-specificattributes,protocolfunctions,andinterfaceaddresses.Therouterwillmakesurethatitcomesupwithtestedhardware.WhenaCiscorouterpowersup,itperformsapower-upself-test(POST).ThesediagnosticsverifythebasicoperationoftheCPU,memory,andinterfacecircuitry.Afterverifyingthehardwarefunctions,therouterproceedswithsoftwareinitialization.Somestartuproutinesactasfallbackoperationsthatareabletoperformtherouterstartupshouldotherroutinesbeunabletodoso.ThisflexibilityallowsCiscoIOSsoftwaretostartupinavarietyofinitialsituations.Slide1of1Purpose:Thisslidedescribethedifferenceoftheconsoleoutputofanunconfiguredrouterversusaconfiguredrouter.Emphasize:Routerhassetupmodetopromptuserforaninitialconfiguration.TheCat1900switchhasnosetupmode,itcomeswithafactorydefaultconfiguration.Thenextseriesofslidesshowsthesetupmodeprompting.Note:Thesetupmodepromptingon12.0isdifferentthanpre-release12.0.Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Oneroutineforinitialconfigurationisthesetupmode.Theprimarypurposeofthesetupmodeistorapidlybringupaminimal-featureconfigurationforanyrouterthatcannotfinditsconfigurationfromsomeothersource.Formanyofthepromptsinthesystemconfigurationdialogofthesetupcommandfacility,defaultanswersappearinsquarebrackets([])followingthequestion.PressingtheReturnkeyallowsyoutousethedefaults.Ifthesystemwaspreviouslyconfigured,thedefaultsthatappeararethecurrentlyconfiguredvalues.Ifyouareconfiguringthesystemforthefirsttime,thefactorydefaultsareprovided.Ifthereisnofactorydefault,asinthecaseofpasswords,nothingisdisplayedafterthequestionmark(?).Atthispoint,youcanchoosenottocontinuewiththesystemconfigurationdialogandcanexitbyenteringNoattheprompt.Tobegintheinitialconfigurationprocess,enterYes.YoucanpressCtrl-Ctoterminatetheprocessandstartoveratanytime.Whenyouareusingthecommandformofsetup(Router#setup),Ctrl-CreturnsyoutotheprivilegedEXECprompt(Router#).Ifa“--More--”promptappears,pressthespacebartocontinue.Note:Whenthestudentperformstheroutersetupmodelablater,makesuretheyselect“no”toWouldyouliketoenterbasicmanagementsetup?[yes/no]:Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Youarepromptedforglobalparametersattheconsole.Youusetheconfigurationvaluesyouhavedeterminedforyourroutertoentertheglobalparametersattheprompts.Thefirstglobalparameterallowsyoutosettherouterhostname.ThishostnamewillprecedetheCiscoIOSpromptersforallconfigurationmodes.Atthefactorytherouternamedefaultisshownbetweenthesquarebracketsas[Router].Usethenextglobalparametersshowntosetthevariouspasswordsusedontherouter.Youmustenteranenablesecretpassword.Whenyouenterastringofpasswordcharactersforthepromptto“Enterenablesecret,”thecharactersareprocessedbyCisco-proprietaryencryption,whichcanenhancethesecurityofthepasswordstring.Wheneveranyoneliststhecontentsoftherouterconfigurationfile,thisenablepasswordappearsasameaninglessstringofcharacters.Setuprecommends,butdoesnotrequire,thattheenablepasswordbedifferentfromtheenablesecretpassword.Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Whenthestudentperformthelablater,makesurethestudentsselect“yes”toConfigureIP?and“no”toallotherprotocols.Slide1of1Purpose:Thisslidedescribethesetupmodeontherouter.Emphasize:Youarepromptedforparametersforeachinstalledinterface.Youusetheconfigurationvaluesyouhavedeterminedforyourinterfacetoentertheinterfaceparametersattheprompts.Lateroninthelab,thestudentswillonlybeconfiguringanIPaddressonE0only.Note:On12.0,thesubnetmaskisactuallyenteredindotteddecimalformat.Slide1of1Purpose:Usethisslidedescribetheoptionsavailablewhenexitingoutofthesetupmodeontherouter.Emphasize:Whenyoucompletetheconfigurationprocess,select[2]tosavetheconfigurationstoNVRAMandmaketheconfigurationactiveinRAM.Ifyouenter[0],theconfigurationisnotsavedtoNVRAMortotheRAM.Note:On12.0,thesearenewoptionstoselectwhenexitingoutofsetupmode.Slide1of1Purpose:UsethisslidetodiscussthetwoExecmodes.Emphasize:Teachyourstudentstolookforandidentifytheprompterthatindicatesiftheyareinthecorrectmodetoenteragivencommand.Slide1of1Purpose:Emphasize:NoticethattherearemorecommandsavailableontherouterthantheCat1900switch.Slide1of1Purpose:Emphasize:NoticethattherearemorecommandsavailableontherouterthantheCat1900switch.Slide1of1Purpose:Emphasize:Note:TheCat1900hasafixedhistorysizeof10whichcan’tbechanged.Slide1of1Purpose:Emphasize:Supposeyouwanttosettherouterclock.Ifyoudonotknowthecommand,usecontext-sensitivehelptocheckthesyntaxforsettingtheclock.Thehelpoutputshowsthatthesetkeywordisrequired.Next,checkthesyntaxforenteringthetime.Nowenterthecurrenttimeusinghours,minutes,andseconds,asshown.Thesystemindicatesthatyouneedtoprovideadditionalargumentstocompletethecommand.PressCtrl-P(orUparrow)torepeatthepreviouscommandentryautomatically.Thenaddaspaceandaquestionmark(?)torevealtheadditionalarguments.Nowyoucancompletethecommandentry.Thecaretsymbol(^)andhelpresponseindicateanerror.Tolistthecorrectsyntax,reenterthecommanduptothepointwheretheerroroccurred,andthenenteraquestionmark(?).EntertheyearusingthecorrectsyntaxandpressReturntoexecutethecommand.Notethattheuserinterfaceprovidessyntaxcheckingintheformofanerrorlocationindicator(^).Thecaretsymbolcharacterappearsatthepointinthecommandstringwhereyouhaveenteredanincorrectcommand,keyword,orargument.Theerrorlocationindicatorandinteractivehelpsystemallowyoutofindandcorrectsyntaxerrorseasily.Slide1of1Purpose:Emphasize:Slide1of9Purpose:ThisslideexplainhowtousetheeditingcapabilitiesofCiscoIOSsoftware. Emphasize:Layer1—Somecommandscanbelongerthanthenumberofcharactersavailableonthescreenaftertheprompt.Theuserinterfacenowsupportsautomaticscrollingoflonglines.Noticethatwehaverunoutofroomonthisline.Thelinewillscrollovertenspacesatatimeinordertoallowlongerlines. Slide2of9Purpose:Emphasize:Layer2—Hereisthesamelineafterithasstartedscrolling.Noticethatadollarsign($)appearsatthebeginningofthelineaftertheprompt.Thisspecialcharacterindicatesthatmorecharacterstotheleftarenotshown.Slide3of9Purpose:Emphasize:Layer3—Theinterfaceimplementssomesophisticatedmotioncommandsforworkingwiththescrolledline.Forexample,ifyouwanttoseethebeginningoftheline,pressCtrl-Atoplacethecursoronthefirstcharacterofaline.Slide4of9Purpose:Emphasize:Layer4—Ctrl-Emovestotheendoftheline.Slide5of9Purpose:Emphasize:Layer5—Esc-Bmovestothebeginningofthepreviousword.Slide6of9Purpose:Emphasize:Layer6—Ctrl-Fmovesforwardonecharacter.Slide7of9Purpose:Emphasize:Layer7—Ctrl-Bmovesbackonecharacter.Slide8of9Purpose:Emphasize:Layer8—Esc-Fmovesforwardoneword.UsetheDeleteandBackspacekeystoremoveandchangecharactersinthecommandline.Ctrl-Uerasesthetextfromthebeginningofthecommandline.TousetheCtrl+keycombination,holddowntheCtrlkeywhilepressingthedesiredletterkey.TousetheEsc+keycombination,pressandreleasetheEsckeythenpressthedesiredletterkey.Toturnofftheeditmode,entertheterminalnoeditcommand.Editmodeisenabledbydefault.Usethe“showterminal”execcommandtoseeifeditmodeisenabledornot.Note:Theterminaleditingmodecan’tbedisabledontheCat1900.Slide9of9Purpose:Emphasize:Layer9—Ctrl-Ddeletesasinglecharacter.Slide1of1Purpose:Emphasize:Theuserinterfaceprovidesahistoryorrecordofcommandsyouhaveentered.Thisfeatureisparticularlyusefulforrecallinglongorcomplexcommandsorentries.Withthecommandhistoryfeature,youcancompletethefollowingtasks:SetthecommandhistorybuffersizeRecallcommandsDisablethecommandhistoryfeatureBydefault,commandhistoryisenabledandthesystemrecords10commandlinesinitshistorybuffer.Tochangethenumberofcommandlinesthesystemwillrecordduringthecurrentterminalsession,usetheterminalhistorysizeorhistorysizecommand.Themaximumnumberofcommandsis256.Torecallcommandsinthehistorybufferbeginningwiththemostrecentcommand,pressCtrl-PortheUparrowkey.Repeatthekeysequencetorecallsuccessivelyoldercommands.ToreturntomorerecentcommandsinthehistorybufferafterrecallingcommandswithCtrl-PortheUparrow,pressCtrl-NortheDownarrow.Repeatthekeysequencetorecallsuccessivelymorerecentcommands.Onceyouentertheuniquecharactersforacommand,presstheTabkeyandtheinterfacewillfinishtheentryforyou.Onmostlaptopcomputersyoumayalsohaveadditionalselectandcopyfacilitiesavailable.Copyapreviouscommandstring,thenpasteorinsertitasyourcurrent.Note:TheCat1900hasafixedhistorysizeof10whichcan’tbechanged.Slide1of1Purpose:Thisslidepresentstheshowversioncommand.Emphasize:Pointoutthatthiscommandisusefulwhentroubleshootingproblemsbecauseitgivestheversionsofthevarioussoftwarecomponentsandfiles.Italsodisplayshowlongtherouterhasbeeninoperationandwhereitobtainedtheimagefile.ConfigregisterisdiscussedinChapter6. Slide1of1Purpose:Emphasize:Whenyouexitthesetupmode,theconfigurationcanbesavedtoRAMandNVRAMatthesametime.Note:TheCat1900hasno“showstart”command.ItautomaticallysavestherunningconfigurationtoNVRAM.Slide1of1Purpose:Thisslideshowstheformatandoutputoftheshowrunning-configandshowstartup-configcommands,whichdisplaytheactiveandbackupconfigurationfiles,respectively.Emphasize:Weputthesetwocommandsonthesamepagebecauseitiseasytoconfusethetwo.Theshowrunning-configcommanddisplaystheconfigurationinformationinmemory,whiletheshowstartup-configcommanddisplaysthebackupfile.Ofteninclasssomeonewillentercommandsandthensaythattherouterdidnotacceptthem.Thisscenariomightindicatethatthepersonenteredthecommandstomodifytheconfigurationinformationinmemory,andthenenteredashowstartup-config(showconfig)tolookatthebackupfilethathasnotyetbeenupdatedtoreflectthechanges.Youmustuseanothercommandtoupdatethebackupfile.Defaultparametersdonotdisplayintherunningconfiguration. InCiscoIOSRelease10.2andearlier,thecommandwriteterminalshowstherunningconfiguration,andthecommandshowconfigshowsthestartupconfiguration.Slide1of1Purpose:Emphasize:Hereisalistofsomeoftheconfigurationmodesavailable.Foracompletelistoftherouterconfigurationmodes,refertotheCiscoDocumentationCD-ROM.Slide1of1Purpose:Emphasize:CopyingtoNVRAMoverwritesthecontentsinNVRAM.Slide1of2Purpose:Thispageexplainshowtoidentifyroutersonthenetwork.Emphasize:Layer1—Tomakeconfiguringandmaintaininganetworkeasier,severalfeaturesproviderecordinganddescriptiveinformationintheconfigurationoftherouter.Thefirstisthehostname,whichissimplyanamebywhichthisrouterisknowninthenetwork.Whenyoulogintoarouter,thehostnameisdisplayedintheprompt.Thisfeatureisveryconvenientwhenyouareremotelyconfiguringrouters,becauseitisaquickreminderofwhichrouteryouareaccessing.Thisnameisalsousedwhenaddressingroutersacrossthenetwork.Hereisanexamplebanner.Themotdkeywordstandsfor“messageoftheday.”Thepoundsign(#)aftermotdisadelimiter.Thebannermessagebeginsafterthischaracterandendswhenthischaracternextappearsinthetext.Youcanhavemanylines—afullscreen—andifyouknowhowtoenterthespecialcommandsforVTextendedmodes,youcangetelongatedandhighlightedcharactersinyourbanner.Ifyouarenotinasecurenetwork,abannerisagoodplacetoputnetworkmaintenanceinformationsuchasthedescriptionofuserswhodependonthisrouterandwheretherouterislocated.Rememberthatanyonecanseethisinformation.Youshouldbeverycarefulaboutthewordingofyourbannermessage.Includingtheword“Welcome”inabannerisanexplicitinvitationtoanyone,includinghackers,toenteryournetwork.Slide2of2Purpose:Emphasize:Layer2—Theinterfacedescriptioncommandallowsyoutoenteraone-linedescriptivestatementforeachinterface.Thisdescriptionisdisplayedintheoutputfromtheshowinterfacescommandandappearsintheshowrunning-configandshowstartup-configlistings. Slide1of2Purpose:Thispageexplainshowtoconfigurepasswords. Emphasize:Layer1—Theconsolepasswordissetindependentlyfromotherlinepasswords,suchasvirtualterminalpasswords.Ifyourconsoleisinyourofficeunderlockandkey,thenyoumaynotneedaconsolepassword;justpressReturnandyouwillbeinusermodeautomatically.However,ifyourconsoleisoutwhereanyonehasaccesstoit,youmightwanttoputapasswordontheconsoleline.Passwordsarecase-sensitivesobeawareiftheCapsLockkeyisonoroff.Thevirtualterminalpasswordmustbesetforremoteconfigurationsupport.Telnetrequiresapasswordcheck.Thenumbers0and4arearange—thatis,VTYlineszerothroughfour,whichequalsfivelines.Youmightwanttosetoneofthevirtualterminalpasswordstobeunique.Thissettingisusuallydoneinalargenetworkwithmanynetworkadministrators.YousetfouridenticalVTYpasswordssothateveryonecangetintotherouter,andsetoneVTYpasswordtosomethingelse.Thisway,ifacatastrophicproblemoccursonthenetworkandallcommonVTYlinesareinuse,theoneuniquelineisinreserveforrecovery.Slide2of2Purpose:Emphasize:Therouterhasoneenablepassword.Rememberthatthisisyouronlyprotection.Whoeverownsthispasswordcandoanythingwiththerouter,sobecarefulaboutcommunicatingthispasswordtoothers.Toprovideanadditionallayerofsecurity,particularlyforpasswordsthatcrossthenetworkorarestoredonaTFTPserver,youcanuseeithertheenablepasswordorenablesecretcommands.Bothcommandsaccomplishthesamething;thatis,theyallowyoutoestablishanencryptedpasswordthatusersmustentertoaccessenablemode(thedefault),oranyprivilegelevelyouspecify.Ciscorecommendsthatyouusetheenablesecretcommandbecauseitusesanimprovedencryptionalgorithm.UsetheenablepasswordcommandonlyifyoubootanolderimageoftheCiscoIOSsoftware,orifyoubootolderbootROMsthatdonotrecognizetheenablesecretcommand.Ifyouconfiguretheenablesecretpassword,itisusedinsteadoftheenablepassword,notinadditiontoit.Ciscosupportspasswordencryption.Turnonpasswordencryptionusingtheservicepassword-encryptioncommand.Thenenterthedesiredpasswordsforencryption.Immediately,onthenextline,enterthenoservicepassword-encryption.Onlythosepasswordsthataresetbetweenthetwocommandswillbeencrypted.Ifyouenterservicepassword-encryptionandthenpressCtrl-Ztoexit,allpasswordswillbeencrypted.Note:Passwordrecoveryisnotcoveredinthecoursematerials.ReferthestudentstotheIMCRclass. Slide1of1Purpose:Emphasize:Ifthestudententers“noexec”bymistake,theconsoleportExecmodewillbedisabledonceloggedoutofthecurrentsession.Ifthishappen,youhavetobreakintototherouterusingROMmonitortorecover(settheconfigregto0x2142soitwillignoreNVRAM).Slide1of1Purpose:Thispageshowstheinterfaceconfigurationmode.Emphasize:Thetoplineistheformatofthecommandusedinfixed-portrouters.Thetypefieldshowstheinterfacetype,whichcanbeEthernet,TokenRing,oranotherinterface.Thenumberfieldisthenumberoftheinterface.Forexample,iftherouterhastwoEthernetinterfaces,andoneisknownasEthernet0,theotherwillbecalledEthernet1.ThesecondcommandisusedontheCisco7000and7200seriesrouters,whichcanacceptmultipleinterfacecardswithmultipleportsoneachcard.Inthiscase,thefirstnumberisthenumberofthecard,orslotnumber.Thesecondnumberistheportonthecard.Forexample,onthesecondinterfacecard,thefirstEthernetinterfaceisspecifiedasEthernet2/0.IfyouhaveCisco7000and7500seriesrouterswithVIPcards,youdefineaninterfaceinthebyslot,portadapters,andportnumbers.Portadaptersareassignedeithera0or1number.Usetheexitcommandtoleavethecurrentconfigurationmode. Slide1of2Purpose:Thispageshowsexamplesofthecommandsusedtoconfigureaserialinterface. Emphasize:Layer1—Inthisexample,weareconfiguringtheserialinterfacefromtheconsoleport.Theconfigureterminalcommandputsusinglobalconfigurationmode.Onceinglobalconfigurationmode,youmustidentifythespecificinterfaceagainstwhichyouwillbeissuingcommands.Noticeafteryouenterthespecificinterfacecommandthatthepromptnowindicatesyouareininterfaceconfigurationmode.Slide2of2Purpose:Thisslideshowstwoconfigurationparametersfortheserialinterface.Emphasize:Layer2—Issuetheclockratecommandwiththedesiredspeed.Onseriallinks,onesideofthelinkactsasdatacommunicationsequipment(DCE)andtheothersideofthelinkactsasthedataterminalequipment(DTE).Bydefault,CiscoroutersareDTEdevices,butcanbeconfiguredasDCEdevices.Ina“back-to-back”cableconfigurationwhereamodemisnotused,oneendmustprovidetheclockingsignal.YoumustspecifyclockratefortheDCEinterfaceendinthistypeofenvironment.Desiredclockrateisinbitspersecond.Besuretotypethecompleteclockspeed.Forexample,aclockrateof56000cannotbeabbreviatedto56.IfyouareusinganRS232cable,usingahighclockratemaycauseerrorsontheline.Usetheshowcontrollerserial0commandtoverifyiftherouterhasaDCEorDTEcableconnectedtoit.Note,therouteronlyreadstheDCE/DTEcableinformationatstartup.Thebandwidthcommandoverridesthedefaultbandwidth(1.544M).TheBandwidthparameter(inkbps)isusedtocalculatestatisticlikeloadanditisusedbyroutingprotocolssuchasIGRP.WewilllearnmoreaboutroutingprotocolsinChapter9.ToreturntoprivilegedEXECmode,typeexituntiltheprivilegedEXECpromptappears.Note:Inthelab,thecorerouterhastheDCEcablesandtheworkgrouprouterhastheDTEcable.Slide1of1Purpose:Thisslideshowsyouhowtoverifythechangesyoumaketoaninterface.Emphasize:Noticethebandwidthhasbeenchangedto64Kfromthedefaultof1.544M.Slide1of1Purpose:Emphasize:Cat1900switchalsousesthe“shut”and“noshut”command.Slide1of1Purpose:Thisslidepresentstheshowinterfacescommand,whichindicateswhetherthenetworkisoperatingatthephysicalanddatalinklayers.Thecommandoutputisinterpretedlaterinthischapter.Emphasize:Thetoplineoftheoutputtellsusthatthelineisup.Afewlinesdown,theoutputprovidestheIPaddress,andbelowthatsomecharacteristicslikeBWforbandwidth;DLYfordelay.Onthenextlinedown,wefindencapsulationtype“ARPA”.ARPAmeansEthernetII,whichisthedefaultIPencapsulationtypeforethernetinterfacesonCiscorouters.Aruntisanethernetframethatistoosmalltobelegal(lessthan64bytes),andagiantisanethernetframethatistoobig(greaterthan1518bytes). Slide1of1Purpose:ThisslideexplainshowtointerprettheshowinterfacesserialcommandoutputEmphasize:.Theshowinterfacesserialcommandoutputindicatesthattheserialinterfaceisupandthelineprotocolisup.ThefirstparameterreferstothehardwarelayerandessentiallyreflectswhethertheinterfaceisreceivingtheCarrierDetectsignalfromtheotherend.Thesecondparameterreferstothedatalinklayer.Thisparameterreflectswhetherthedatalinklayerprotocolkeepalivesarebeingreceived.Ifboththeinterfaceandthelineprotocolareup,theconnectionisoperational.Ifthehardwareisupandthelineprotocolisdown,aconnectionproblemexistsuchasnoclocking,wrongencapsulationtype,ornokeepalives.Ifboththelineprotocolandtheinterfacearedown,acablemightneverhavebeenattachedtotherouter.Ontheserialcable,youcanpluginthecableupsidedowncausingthepinsontheserialcabletobreak.Thereisonemorepossibility.Iftheinformationsays“administrativelydown,”youhavemanuallydisabled(shut)theinterface.Ciscooffersahardwareclass(IMCR)thatdiscussestherouterhardwareinmoredetail. Slide1of1Purpose:Emphasize:Thiscommandrequiresaspacebetweentheword“serial”andtheinterfacenumber.Therouteronlychecksforthecabletypeatpowerup.Purpose:ThisfigureshowscommandsusedtoconfigureIPaddressesonaCatalyst1900seriesswitch.Emphasize:TheIPaddressonaswitchistypicallyassignedgloballytothedevice.Onarouter,eachinterfacehasauniqueaddress.Theipdefault-gatewaycommandspecifiesadefaultgatewaytotherouter. Purpose:ThisfigureshowscommandsusedtoconfigureIPaddressesonarouter.Emphasize:TheIPaddressonaswitchistypicallyassignedgloballytothedevice.Onarouter,eachinterfacehasauniqueaddress. Purpose:ThisfigureshowsoptionalIPaddressformatcommandsusedtodisplayIPaddressesonarouter.Emphasize:Thecommandspresentedarefordisplaypurposesonly.Whenconfiguringarouter,youmuststillusetherequiredconfigurationformat.Forexample,whenconfiguringanIPaddressonaninterface,youmustconfigurethesubnetmaskindotteddecimalformat. Purpose:ThisfigureshowshowtheiphostcommandisusedtomapanIPaddresstoaspecifichostname. Emphasize:Describetheiphostcommand. Purpose:Thisfigureshowscommandsusedtoconfigurenameservers. Emphasize:Describetheipname-servercommand. ExplainDomainNameSystem(DNS)andhowitworks.DNSisahostsystemusedinthenetworkfortranslatingnamesofnetworknodesintoaddresses.Purpose:ThisfigureshowscommandsusedtoenabletheroutertouseDNS.Emphasize:Describethecommands. Ifthestudentshaveaccesstoconsoleterminals,youmayhavethementerthenoipdomain-lookupcommandnow.HavingDNSserveronbydefaultwillcausedelaysinlabsbecause,whenthestudentstypeaninvalidcommand,thedefaultwillbetolookforadomainnameservertointerpretthatcommand. Purpose:Thisfigureshowscommandsusedtodisplaythecachedlistofhostnames.Emphasize:Describetheshowhostscommandoutput.