【Juniper】JNCIS-ENT JN0-349认证考试题库及答案

PAGEPAGE1【Juniper】JNCIS-ENTJN0-349认证考试题库及答案一、单选题1.ClicktheExhibitbutton.Youarebuildinganetworkandmakesomeconfigurationchanges.Whiletryingtovalidatethesechanges,youreceivetheerrorshownintheexhibit.Howwouldyousolvethisproblem?A、Youmustconfiguretheportmodeastrunkonthege-0/0/5.0interface.B、YoumustcreateanewVLANcalleda11usingtheVLANIDof30.C、Youmustconfigurethege-0/0/5.0interfacewithfamilyinetinsteadoffamilyethernet-awitching.D、Youmustcreatetwosub-interfacesonge-0/0/5withtheappropriateVLANmemberassignedtoeach.答案：A2.YouareaddinganewEX4300memberswitchtoyourexistingEX4300VirtualChassis.However,thenewmemberisnotrunningthesameJunosversionastheothermembers.Bydefault,whatistheexpectedbehavior?A、ThenewswitchisnotrecognizedbytheVirtualChassis.B、TheVirtualChassiswilltransitionintoasplitbrainsituationbetweentheexistingmasterRoutingEngineandtheswitchrunningthedifferentversion.C、ThenewswitchwillbeassignedamemberIDandthenplacedinaninactivestate.D、ThenewswitchwillautomaticallypullthecorrectversionfromthemasterRoutingEngineandperformthenecessaryupgrade.答案：D3.YouhaveanIBGPneighborsendingyouroutes.Youneedtoapplyapolicysoitonlyevaluatesroutesbeinglearnedfromthisspecificneighbor.

Inthisscenario,whichstatementiscorrectaboutapplyingthepolicy?A、ThepolicyshouldbeappliedasanimportpolicytotheBGPgrouplevel.B、ThepolicyshouldbeappliedasanexportpolicytotheBGPgrouplevel.C、ThepolicyshouldbeappliedasanimportpolicytotheBGPneighborlevel.D、ThepolicyshouldbeappliedasanexportpolicytotheBGPneighborlevel.答案：C4.ClicktheExhibitbutton.Referringtotheexhibit,whatistheproblem?A、LAGrequiresmorethantwomemberlinks.B、LACPisrequiredforLAGtowork.C、Aggregatedinterfacesmustbedefinedunderthechassisstanza.D、TheLAGmemberinterfacesareconfiguredacrossdifferentlinecards.答案：C解析：Usethelinkaggregationfeaturetoaggregateoneormorelinkstoformavirtuallinkorlinkaggregationgroup(LAG).5.WhatisthedefaultroutepreferenceforBGP?A、150B、167C、170D、179答案：C6.Whichmechanismisusedtoshareroutesbetweenroutingtables?A、filter-basedforwardingB、forwardinginstancesC、RIBgroupsD、routinginstances答案：C解析：

ARIBgroupisawaytohavearoutingprotocol,inmostcases,placeinformationinmultipleroutetables.7.Whichstaticroutenext-hopvalueindicatedthatthepacketwillbesilentlydropped?A、resolveB、discardC、rejectD、next-table答案：B8.ClicktheExhibitbutton.TheconfigurationshownintheexhibitwasmittedonanEXSeriesswitch.YouarenotifiedthatthephoneusingthevoiceVLANdoesnotwork.Youdeterminethatvoicetrafficisnotpassingthroughthelocalswitch.Whatshouldbedonetosolvetheproblem?A、YoushouldaddthevoiceVLANasamemberonthege-0/0/8.0interface.B、Youshouldchangetheportmodeonge-0/0/9.0totrunk.C、YoushouldaddthevoiceVLANasamemberonthege-0/0/9.0interface.D、YoushouldchangethevoiceVLANIDtomatchthedataVLANID.答案：A9.YouconfiguredaGREtunnelthattraversesapathusingdefaultMTUsettings.Youwanttoensurethatpacketsarenotdroppedorfragmented.

Inthisscenario,whatisthemaximumpacketsizethatwouldtraversetheGREtunnel?A、1476B、1500C、1400D、1524答案：A解析：

ThedefaultEthernetMTUis1500.Thereisa24byteGREoverhead,sothereremain1476bytesforthedatapacket.Reference:/InfoCenter/index?page=content&id=KB7848&actp=search10.ClicktheExhibitbutton.Referingtotheexhibit,whichrouterwillbeselectedastheDR?A、R4B、R1C、R5D、R3答案：D11.WhichareaisreservedfortheOSPFbackbone?A、AreaB、AreaC、AreaD、Area答案：A12.Switch-1intheexhibitreceivesapacketfromUserAwithadestinationMACaddressof00:26:88:02:74:47.Whichstatementiscorrectinthisscenario?A、Switch-1floodsthepacketoutge-0/0/6,ge-0/0/7,ge-0/0/8,andge-0/0/9.B、Switch-1floodsthepacketoutge-0/0/7andge-0/0/8.C、Switch-1floodsthepacketoutge-0/0/7,ge-0/0/8,andge-0/0/9.D、Switch-1sendsthepacketoutge-0/0/7only.答案：C解析：Toforwardaframedestinedtothatspecificmac-address,itwillknowoutofwhichporttosendtheframe.Floodinghoweveroccurswhentheswitchdoesnotknowofthedestinationmac-address?saytheswitchhasnotlearntthatmacaddressyet;ormaybethatspecificentryexpiredsoitgotflushedawayfromthemac-addresstable.Toensuretheframereachesitsintendeddestination,theswitchwillreplicatethatframeoutofallports,lesstheportwheretheframewasreceivedthat'sflooding.Reference:/index.php/2015/03/mac-address-table-arp-table-and-unicast-flooding-part-i/13.ClicktheExhibitbutton.YouaretroubleshootingOSPFissuesonyourdevice.Yourunatracelogandreceivetheerrorshownintheexhibit.Whatwouldcausethiserror?A、stubareamismatchB、subnetmismatchC、MD5authenticationerrorD、missingroutepolicy答案：A14.YouhavedeployedaJuniperEXSeriesswitchinthenetwork.Theswitchreceivesabroadcastframeonaninterface.Whichstatementdescribesthebehavioroftheswitch?A、TheframeisfloodedoutallportsthatarepartofthesameVLANasthereceivingport,exceptfortheportonwhichtheframewasreceived.B、TheframeisfloodedoutallportsinallVLANsconfiguredontheswitch.C、Theframeisre-transmittedasamulticastframeonallportsontheswitch.D、TheframeisfloodedoutallportsthatarepartofthesameVLANasthereceivingport,includingtheportonwhichtheframewasreceived.答案：A15.ClicktheExhibitbutton.Referringtotheexhibit,whichsetofinterfacesisenabledforEthernetswitching?A、ge-0/0/6,ge-0/0/8,andge-0/0/10B、ge-0/0/6,ge-0/0/7,andge-0/0/8C、ge-0/0/6andge-0/0/8D、ge-0/0/6,ge-0/0/7,ge-0/0/8,andge-0/0/10答案：D16.ClicktheExhibitbutton.Referringtotheexhibit,whicheffectdoestheconfigurationonR2haveonOSPFroutinginthenetwork?A、R2willblocktrafficdestinedtothe/24network.B、Asummaryrouteforthe/24networkwillbeadvertisedtoArea0.C、The/24routewillnotbeadvertisedtoArea1.D、Area2willuseadefaultroutetoreachArea0andArea1.答案：B17.Youareaskedtoconfigurefilte-basedforwarding(FBF)toforwardtrafficsourcedfromaspecificsubnettoawebserver.

Inthisscenario,whichmechanismisusedtoaddinterfaceroutestotheforwardingroutinginstanceusedinFBF?A、routingpolicyB、forwardingpolicyC、RIBgroupsD、generatedroutes答案：C18.ClicktheExhibitbutton.Referringtotheexhibit,whenusingthedefaultroutingbehavior,whathappenstoPacketAandPacketBonR1?A、PacketAisrejectedandPacketBisforwardedtoitsdestination.B、PacketAisforwardedtoitsdestinationandPacketBisrejected.C、PacketAandPacketBareforwardedtotheirrespectivedestinations.D、PacketAandPacketBarediscarded.答案：B19.WhichstatementiscorrectabouttheOSPFrouterID(RID)?A、TheOSPFRIDmustmatchforallroutersinthesamearea.B、TheOSPFRIDforIPv6isa128-bitaddress.C、TheOSPFRIDforIPv4isa32-bitaddress.D、TheOSPFRIDisnotnecessarywhenBFDisimplemented.答案：C20.ClicktheExhibitbutton.TheexhibitshowsthatHost-1andHost-2areattachedtotheswitchandassociatedwithIRBirb.1.However,trafficsentfromHost-1toHost-2isnotblockedasexpected.Whyisthisproblemoccurring?A、Inter-VLANtrafficcannotbeblockedbyarouter-basedfilter.B、Theblock-hostfilterisappliedinthewrongdirectionontheirb.1interface.C、TheBlock-Host-2termdoesnotcontaintheMACaddressofHost-2.D、Intra-VLANtrafficcannotbeblockedbyarouter-basedfilter.答案：B解析：Theblock-hostfilterblockstrafficwithsourceaddressof02,whichistrafficsentfromHost-2.ItShouldblocktrafficfromHost-1,withthesourceaddressof01.21.YoumustlimitaccesstoaprinterwithapersistentDHCPaddressof2001:db8:0000:50::10/64inVLANv50tousersassignedtoVLANv50only.

Whichactionwouldsatisfythisrequirement?A、ImplementafirewallfilerontheIRBinterfaceforVLANv50,blockingtrafficto/from2001:db8:0000:50::10.B、ImplementpersistentMAClearningtoensurethat2001:db8:0000:50::10isallocatedproperly.C、ImplementDHCPsnoopingonVLANv50toensurethat2001:db8:0000:50::10isallocatedproperly.D、ImplementafirewallfilterontheVLANv50,blockingtrafficto/from2001:db8:0000:50::10.答案：A22.ClicktheExhibitbutton.AroutingtablecontainsmultipleBGProutestothesamedestinationprefix.Theroutepreferenceisthesameforeachroute.Referringtotheexhibit,whichroutewouldbeselected?A、routeBB、routeDC、routeAD、routeC答案：A23.ClicktheExhibitbutton.Referringtotheexhibit,whichpolicywillexportroutestoIBGPpeers?A、static-4B、static-1C、static-3D、static-2答案：A解析：Explanation;TypeinternalingrouptwoindicatesreferstoanIBGProute.Reference:http://./documentation/en_US/junos13.3/topics/topic-map/bgp-ibgp-peering.html24.AnEXSeriesswitchreceivesaframewithanunknowndestinationMACaddress.

Whatistheexpectedbehavior?A、TheframeissentoutallportsassignedtoallconfiguredVLANsexcepttheingressportonwhichtheframewasreceived.B、TheframeissentoutallaccessportsassociatedwiththeingressVLANregardlessofwhetheramatchingMACaddresswasfoundinthebridgetable.C、TheframeissentoutallportsassignedtotheassociatedVLANexcepttheingressportonwhichtheframewasreceived.D、TheframeissentoutalltrunkportsassociatedwiththeingressVLANregardlessofwhetheramatchingMACaddresswasfoundinthebridgetable.答案：C25.AnOSPFhellopackethasbeensent,butbidirectionalmunicationhasnotbeenestablished.WhatisthestateoftheOSPFadjacency?A、DownB、InitC、ExchangeD、Loading答案：A解析：

DownisthefirstOSPFneighborstate.Itmeansthatnoinformation(hellos)hasbeenreceivedfromthisneighbor,buthellopacketscanstillbesenttotheneighborinthisstate.IncorrectAnswers:

B:TheInitstatespecifiesthattherouterhasreceivedahellopacketfromitsneighbor,butthereceivingrouter'sIDwasnotincludedinthehellopacket.Reference:http://.cisco./c/en/us/support/docs/ip/open-shortest-path-first-ospf/13685-13.html26.ClicktheExhibitbutton.Referringtotheexhibit,youareaskedtoensurethathost-1canmunicatewithhost-3whilealsoallowinghost-2tomunicatewithhost-4.Whatshouldyoudotoenablethisbehavior?A、Configurethenative-vlan-iddefaultstatementunderthege-0/0/1portsettingsonSwitch-1.B、UsetheallkeywordwhendefiningthememberVLANsforthege-0/0/1interfaceonSwitch-1.C、Configurethenative-vlan-iddefaultstatementunderthege-0/0/1portsettingsonbothSwitch-1andSwitch-2D、UsetheallkeywordwhendefiningthememberVLANsforthege-0/0/1interfaceonbothSwitch-1andSwitch-2.答案：C解析：ConfiguringMixedTaggingSupportforUntaggedPacketsFor1-,4-,and8-portGigabitEthernetIQ2andIQ2-EPICs,for1-port10-GigabitEthernetIQ2andIQ2-EPICs,forallMXSeriesrouterGigabitEthernet,Tri-RateEthernetcopper,and10-GigabitEthernetinterfacesconfiguredfor802.1QflexibleVLANtagging,andforaggregatedEthernetinterfacesonIQ2andIQ2-EPICsorMXSeriesDPCs,youcanconfiguremixedtaggingsupportforuntaggedpacketsonaport.UntaggedpacketsareacceptedonthesamemixedVLAN-taggedport.Toacceptuntaggedpackets,includethenative-vlan-idstatementandtheflexible-vlan-taggingstatementatthe[editinterfacesinterface-name]hierarchylevel:[editinterfacesge-fpc/pic/port]flexible-vlan-tagging;native-vlan-idnumber;Reference:https://./documentation/en_US/junos13.3/topics/usage-guidelines/interfaces-enabling-vlan-tagging.html27.ClicktheExhibitbutton.Switch-1intheexhibitreceivesapacketfromUserAwithadestinationMACaddressof00:26:88:02:74:47.Whichstatementinthisscenarioiscorrect?A、Switch-1sendsthepacketoutge-0/0/7andge-0/0/8.B、Switch-1sendsthepacketoutge-0/0/7only.C、Switch-1sendsthepacketoutge-0/0/7,ge-0/0/8,andge-0/0/9.D、Switch-1sendsthepacketoutge-0/0/6,ge-0/0/7,ge-0/0/8,andge-0/0/9.答案：B28.ClicktheExhibitbutton.YouhaveanexistingVirtualChassisconsistingoffivememberdevices.Member3failsandmustbereplaced.YouremovetheEXSeriesswitchwithaMemberIDof3andinstallareplacementswitchinitsplaceusingidenticalcablingasshownintheexhibit.Thereplacement’smemberIDis6,sotheconfigurationformemberID3isnotappliedtoit.Referringtotheexhibit,whatshouldhavebeendonebeforeinstallingthereplacementswitch?A、ReactivatetheVirtualChassis.B、RecyclethememberIDoftheswitchbeingreplaced.C、RenumberthememberIDs.D、CleartheVirtualChassisprotocol.答案：B29.ClicktheExhibitbutton.Therearedynamicallyandstaticallyroutednetworksattachedtothege-0/0/1interfaceonR1.YouonlywantthedynamicallylearnedroutestoshowupinroutingtablesforR2andR3,butthestaticallyroutednetworksarealsoappearing.ThosenetworksshouldonlybeseenbytheR1device.Whichactionswouldsolvetheproblem?A、RemovetheIPaddressfrominterfacege-0/0/1.B、Addtheno-readvertiseparametertothestaticroutes.C、Createaroutingpolicyforallroutingprotocolstodroprouteslearnedfrominterfacege-0/0/1.D、Placeinterfacege-0/0/1intoitsownroutinginstance.答案：B30.ClicktheExhibitbutton.Referringtotheexhibit,whichtypeofrouteisdisplayed?A、generate.B、martianC、aggregateD、static答案：C解析：Fromtheexhibitsesee:ContributingRoutesNote:Routeaggregationallowsyoutobinegroupsofrouteswithmonaddressesintoasingleentryintheroutingtable.Thisdecreasesthesizeoftheroutingtableaswellasthenumberofrouteadvertisementssentbytheroutingdevice.AnaggregateRoutebeesactivewhenithasoneormorecontributingroutes.Acontributingrouteisanactiveroutethatisamorespecificmatchfortheaggregatedestination.Reference:http://./techpubs/en_US/junos15.1x49-d40/topics/concept/policy-aggregate-routes.html31.Whichprotocolsupportstunnelingofnon-IPtraffic?A、GREB、SSHC、IPsecD、IP-IP答案：A解析：

TheGREprotocol(GenericRoutingEncapsulation)whichisatunnelingprotocolthatcanencapsulateavarietyofnetworklayerpackettypesintoaGREtunnel.GREthereforecanencapsulatemulticasttraffic,routingprotocols(OSPF,EIGRPetc)packets,andothernon-IPtrafficinsideapoint-to-pointtunnel.Reference:

Http://.networkstraining./passing-non-ip-traffic-over-ipsec-vpn-using-gre-over-ipsec/32.ClicktheExhibitbutton.Referringtotheexhibit,whatdoestheasterisk(*)indicate?A、Therouterreceivedthisentry.B、Thisentryisstale.C、Thisentryisnew.D、Therouteroriginatedthisentry.答案：C解析：Theasterisk(*)nexttooneoftheblockentriescorrespondstotheactiveroutethatisusedfornewtraffic.Theterm'newtraffic'correspondstoasinglepacketoranentireflowtoadestination,dependingonthetypeofswitchingconfigured.Reference:http://.cisco./c/en/us/support/docs/ip/border-gateway-protocol-bgp/5212-46.html33.ExhibitClicktheExhibitbutton.AroutingtablecontainsmultipleBGProutestothesamedestinationprefix.Theroutepreferenceisthesameforeachroute.Referringtotheexhibit,whichroutewouldbeselected?A、routeDB、routeCC、routeBD、routeA答案：C34.ClicktheExhibitbutton.Basedonthetraceoptionsoutputshownintheexhibit,whatistheproblemwiththeadjacency?A、connectivityB、authenticationmismatchC、areamismatchD、MTUmismatch答案：C解析：Fromtheexhibitwesee:OSPFpacketignored:areamismatch35.ClicktheExhibitbutton.Referringtotheexhibit,whichtypeofrouteisdisplayed?A、staticB、generateC、aggregateD、martian答案：C解析：Fromtheexhibitwesee:/8*[Aggregate/130]36.ClicktheExhibitbutton.YouareestablishingaBGPsessionbetweenR1andR2.R2showsasitspeeraddressforR1insteadof.Referringtotheexhibit,whatmustbechangedintheconfiguration?A、Apeer-asstatementmustbeaddedtoR1intheinternalgroup.B、AnexportpolicystatementmustbeaddedtoR1intheinternalgrouptoallowthelo0addresstopeer.C、Alocalinterfacestatementwiththelo0addressmustbeaddedtoR1intheinternalgroup.D、Alocaladdressstatementwiththelo0addressmustbeaddedtoR1intheinternalgroup.答案：D37.ClicktheExhibitbutton.Referringtotheexhibit,whichstatementiscorrect?A、Thisdeviceistherootbridge.B、Thespanningtreesessionhastimedout.C、Thebridgepriorityontherootdeviceissetto8k.D、Thelocalbridgepriorityissetto8k.答案：C解析：TheRootIDfieldistheBridgeIDoftheelectedspanningtreerootbridge.ThebridgeIDconsistsofaconfigurablebridgepriorityandtheMACaddressofthebridge.Herethebridgepriorityis8192,whichis8k.38.ClicktheExhibitbutton.TheIS-ISadjacencybetweenroutersR1andR2willnotestablish.Referringtoexhibit,whatistheproblem?A、TheISOaddressisnotconfiguredoninterfacege-0/0/1.B、Thelevelisnotconfiguredunderprotocolsisis.C、TheIPaddressisnotconfiguredoninterfacelo0.D、ThelinkMTUistoosmalloninterfacege-0/0/1.答案：C39.Whatkindoffilterwouldbewrittentoprotectcontroltrafficdestinedfortheswitch?A、AfilterappliedtothedefaultVLANB、AfilterappliedtothenativeVLANC、AfilterappliedtothemanagementinterfaceD、Afilterappliedtotheloopbackinterface答案：D40.ClicktheExhibitbutton.YouareconfiguringIS-ISonthenewlyprovisionedae88interface.Afteryoumittheconfiguration,younoticethatyouradjacencyisnotshowingup.Referringtotheexhibit,whatisthereasonfortheadjacencybeingdown?A、R1andR2areconfiguredfordifferentmetrics.B、R1andR2havedifferentinterfaceparameters.C、R1andR2areconfiguredfordifferentareas.D、R1andR2areindifferentIS-ISlevels.答案：B41.Youareconcernedthatsomeonefromoutsidethepanycoulduseanopenconferenceroomporttoaccessthenetwork.

Whichfeatureshouldyouusetoaddressthisconcern?A、MAClimitingB、persistentMAClearningC、DHCPsnoopingD、802.1X答案：D42.ClicktheExhibitbutton.YouareresponsibleformanagingaLayer2networkusingRSTPforloopprevention.Yourecentlymittedtheconfigurationsshownintheexhibit.Unfortunately,Switch-2becametherootbridgeandyoumustensurethatSwitch-1beestherootbridge,whenavailable,forthisRSTPtopology.Referringtotheexhibit,whichconfigurationchangeshouldbeperformed?A、Configurethege-0/0/1andge-0/0/8interfacesonSwitch-1tohaveapriorityof255.B、Configurethege-0/0/1andge-0/0/8interfacesonSwitch-1tohaveacostof0.C、ConfigurethesystemMAConSwitch-1tobehigherthantheothertwoswitches.D、Configurethebridge-priorityonSwitch-1as4k.答案：D43.ClicktheExhibitbutton.Referringtotheexhibit,whichstatementiscorrect?A、willbetheactivenexthop.B、willbetheactivenexthop.C、Packetswillbeloadbalanced.D、Nexthopsandwillbothbeactive.答案：B44.ClicktheExhibitbutton.Referringtotheexhibit,whichdeviceswillreceivethepacketsentbyUserB?A、UserAandUserDB、UserC,UserA,andUserDC、UserCD、UserCandUserD答案：D45.ClicktheExhibitbutton.Referringtotheexhibit,whichrouterwillbeselectedastheDR?A、R1B、R5C、R4D、R3答案：D解析：Note:Thehigherthepriorityvalue,thegreaterlikelihoodtheroutingdevicewillbeethedesignatedrouter.Bydefault,routingdeviceshaveapriorityof128.Apriorityof0markstheroutingdeviceasineligibletobeethedesignatedrouter.Apriorityof1meanstheroutingdevicehastheleastchanceofbeingadesignatedrouter.Apriorityof255meanstheroutingdeviceisalwaysthedesignatedrouter.Reference:https://./documentation/en_US/junos16.1/topics/concept/ospf-routing-designated-router-overview.html46.ClicktheExhibitbutton.Basedontheoutputshownintheexhibit,whichstatementiscorrect?A、Thege-0/0/9interfaceisusingthedefaultpriorityvalue.B、Thege-0/0/15interfaceisusingthedefaultportcost.C、Thisswitchhasabridgepriorityof32k.D、Thisswitchhasbeenelectedastherootbridge.答案：D解析：Thedefaultportcostfora100Mbit/sinterfaceis200,000,whichistheportcostofthege-0/0/15interface.Note:DatarateanddefaultSTPpathcost47.ClicktheExhibitbutton.YourpanyhasconnectionstotwoISPs.EachISPisinaseparateroutinginstance.Youneedtoadvertisethe/0prefixfrombothISPstoallyourdevices.Referringtotheexhibit,whichstatementistrueinthisscenario?A、YoumustcreateapolicytoallowtraficfromyournetworktoeachISP.B、Youmustcreateaninternalroutinginstanceforyournetwork.C、YoumustcreateaRIBgrouptoshareinterfaceroutes.D、Youmustcreateandapplymatchinputfiltersoninterfacesge-0/0/2andge-0/0/3.答案：C48.Youwereprovidedanetworkdiagramthattoldyoutonumberyournetworkfromthe/16space.OSPFisenabledandadjacenciesareup,butnoroutersarelearninganyroutes.

Whatcanexplainthis?A、ThedefaultOSPFexportpoliciesadvertisenothing,soyouneedtoapplyexportpolicyB、ThedefaultOSPFimportpolicyrejectsallOSPFroutes,soyouneedtoapplyimportpolicyC、Youneedtomodifythemartiantablewitha/16acceptstatementD、YouneedtoenableOSPFonthelo0interfacetoprovidearoutetotheRIDofeachrouterinthenetwork答案：C49.IfanEXSeriesswitchreceivesaframewithaknowndestinationMACaddress,whatistheexpectedbehavior?A、TheframeissentouttheegressportwithamatchingdestinationMACaddresswithinthebridgetableassociatedwiththeingressVLAN.B、TheframeissentoutalltrunkportsassociatedwiththeingressVLANregardlessofwhetheramatchingMACaddresswasfoundinthebridgeC、TheframeissentoutallportsassignedtoallconfiguredVLANsexcepttheingressportonwhichtheframewasreceived.D、TheframeissentoutallportsassignedtotheassociatedVLANexcepttheingressportonwhichtheframewasreceived.答案：A50.WhatisapurposefortheOSPFdatabasedescriptionpacket?A、totransfertheLSAheadersbetweentwosystemsB、totransfertheLSUsbetweentwosystemsC、todeterminewhoisinchargeofadjacencyformationD、todeterminewhoisinchargeofdatabaseflushing答案：A51.Whichprotocolpreventsloopsandcalculatesthebestpaththroughaswitchednetworkthatcontainsredundantpaths?A、VRRPB、STPC、DHCPD、IS-IS答案：B解析：

SpanningTreeProtocol(STP)isaLayer2protocolthatrunsonbridgesandswitches.ThemainpurposeofSTPistoensurethatyoudonotcreateloopswhenyouhaveredundantpathsinyournetwork52.ClicktheExhibitbutton.Referringtotheexhibit,whatdoestheasterisk(*)followingthege-0/0/5.0interfaceindicat?A、Itindicatestheinterfaceisatrunkport.B、Itindicatestheinterfaceisactive.C、Itindicatestheinterfaceisnotactive.D、Itindicatestheinterfaceisanaccessport.答案：B53.WhichLSAtypedescribestherouterIDofASBRrouterslocatedinremoteareas?A、Type4B、Type5C、Type3D、Type7答案：A54.WhichstatementaboutIS-ISadjacenciesistrue?A、AdjacencyformationbetweenLevel2routersmusthavedifferentareaIDs.B、AdjacencyformationbetweenLevel2routersmusthavethesameareaID.C、AdjacencyformationbetweenLevel1routersmusthavethesameareaID.D、AdjacencyformationbetweenLevel1routersmusthavedifferentareaIDs.答案：C解析：

IS-IShelloPDUsestablishadjacencieswithotherroutersandhavethreedifferentformats:pointto-pointhellopackets,oneforLevel1broadcastlinks,andoneforLevel2broadcastlinks.Level1routersmustsharethesameareaaddresstoformanadjacency,whileLevel2routersdonothavethislimitation.Reference:http://./documentation/en_US/junos15.1/topics/concept/is-is-routing-overview.html55.Whichprotocolsupportstumelingofnon-IPtrafic?A、IPsecB、GREC、IP-IPD、SSH答案：B56.YoumanageaLayer2networkthatspanstwobuildings.Youareaskedtoensurethatalltrafficthattraversesthisconnectionbetweenthetwobuildingsissecured.

WhichportsecurityfeatureshouldbeusedtosecurethisLayer2traffic?A、IPsourceguardB、MACsecC、DHCPsnoopingD、dynamicARPinspection答案：B57.ClicktheExhibitbutton.YouareattemptingtosetupIS-ISonadevicethathastwointerfaces(ge-0/0/1.0andge-0/0/2.0)inLevel1andoneinterface(ge-0/0/0.0)inLevel2;however,itdoesnotparticipateineitherlevel.Referringtotheexhibit,whatistheproblem?A、Thege-0/0/0.0interfacemusthavetheLevel1disablestatementremoved.B、Thelo0interfacemustparticipateinbothlevels.C、Alloftheinterfacesmusthavetheleveldisablestatementremoved.D、Oneoftheinterfacesrequiresanetworkentitytitleonit.答案：D58.Yourrouterislearningthe/24prefixfromboththeBGPandOSPFprotocols.AroutingpolicyisconfiguredonyourdevicetoadvertisetheprefixtoanestablishedBGPpeerbutthepeerisnotreceivingtheprefix.YouwanttoallowtheprefixtobeadvertisedtotheBGPpeer.

Whatshouldyoudoonthisroutertosatisfythisrequirement?A、EnabletheautomaticremovalofprivateASnumbersfromtheprefix.B、EnabletheadvertisementofinactiveBGProutes.C、EnabletheautomaticrefreshingofBGProutes.D、EnabletheautomaticremovalofpeerASinformationfromtheprefix.答案：B59.ClicktheExhibitbutton.WhichaddressfamiliesarenegotiatedbetweenthetwoBGPpeersshownintheexhibit?A、inet-vpn-unicastB、inet-unicastinet-vpn-unicast12vpnC、inet-unicastinet-vpn-unicast12vpn-signalingD、inet-unicast答案：D解析：Fromtheexhibitwesee:NLRIforrestartconfiguredonpeer:inet-unicastinet-vpn-unicast12vpnbutwealsosee:NLRIthatrestateisnegotiatedfor:inet-unicastNLRIofreceivedend-of-ribmarkers:inet-unicastNLRIofallend-of-ribmarkerssent:inet-unicast60.WhatisthedefaultroutepreferenceforBGP?A、167B、170C、150D、179答案：B解析：

BGPhasthedefaultpreferenceof170.Reference:https://./documentation/en_US/junos14.2/topics/reference/general/routing-protocols-default-route-preference-values.html61.ClicktheExhibitbutton.Referringtotheexhibit,whichportonSwitch-2willbeselectedastheRSTProotport?A、ge-0/0/8.0B、ge-0/0/10.0C、ge-0/0/9.0D、ge-0/0/1.0答案：B62.YouarecurrentlydefininganewOSPFarea.Theareamustadvertiseexternalroutesbutshouldnotreceiveexternalroutesfromanotherarea.Inthisscenario,whichtypeofareashouldyoudefine?A、stubB、backboneC、not-so-stubbyD、totallystubby答案：C63.ClicktheExhibitbutton.YoumanagetheLayer2networkshownintheexhibit.Youexperienceafailureonthege-0/0/0linkbetweenSwitch-1andSwitch-2.Whichstatementiscorrectabouttheexpectedbehavior?A、Switch-3’sge-0/0/2portroleandstatewilltransitiontodesignatedandforwarding.B、Switch-3’sge-0/0/2portroleandstatewillremainasalternateanddiscarding.C、Switch-3willbeetherootbridgefortheRSTPtopology.D、Switch-3willremovethege-0/0/2interfacefromtheRSTPtopology.答案：A64.ClicktheExhibitbutton.Whichstatementistleabouttheconfigurationshownintheexhibit?A、Onlytheadv-customexportpolicywillbeevaluatedwhenroutesaresenttoneighbor.B、Boththeadv-aggregateandnext-hop-ae1fexportpolicieswillbeevaluatedwhenroutesaresenttoneighbor.C、Boththeadv-aggregateandadv-customexportpolicieswillbeevaluatedwhenroutesaresenttoneighbor.D、Onlythenext-hop-ae1fexportpolicywillbeevaluatedwhenroutesaresenttoneighbor.答案：A65.ClicktotheExhibitbutton.Referringtotheexhibit,whichrouterwillbeetheBDRifallroutersarepoweredonatthesametime?A、R3B、R2C、R1D、R4答案：A解析：InLANs,theelectionofthedesignatedroutertakesplacewhentheOSPFnetworkisinitiallyestablished.WhenthefirstOSPFlinksareactive,theroutingdevicewiththehighestrouteridentifier(definedbytherouter-idconfigurationvalue,whichistypicallytheIPaddressoftheroutingdevice,ortheloopbackaddress)iselectedthedesignatedrouter.Theroutingdevicewiththesecondhighestrouteridentifieriselectedthebackupdesignatedrouter.Reference:./documentation/en_US/junos16.1/topics/concept/ospf-routing-designated-routeroverview.html66.ClicktheExhibitbutton.YouaretroubleshootinganIS-ISadjacencyproblemasshownintheexhibit.Whichactionwouldsolvetheproblem?A、Configurematchingauthenticationkeys.B、ConfiguretheINET6familyfortheloopbackinterface.C、ConfiguretheISOfamilyfortheloopbackinterface.D、ConfigurematchingareaIDs.答案：D67.EachPCandIPphoneinyournetworkisconnectedtoaswitchusingthesameport.Alliningdatatrafficisuntaggedandbelongstothev10

VLAN,whiletrafficingfromtheIPphonesistaggedwithaVLANvalueof20andshouldbelongtothev20VLANonyourswitch.

Inthisscenario,whichstatementiscorrect?A、YoumustenableLLDP-MEDontheininginterfacesandassignthev20VLAN.B、YoumustenableanIRBinterfaceandassignittothev10andv20VLANs.C、YoumustenabletheguestVLANfeatureontheininginterfacesandassignthev20VLAN.D、YoumustenablethevoiceVLANfeatureontheininginterfacesandassignthev20VLAN.答案：D68.Bydefault,howlongwillalearnedMACaddressberetainedinthebridgetableonanEXSeriesswitch?A、600secondsB、3600secondsC、300secondsD、1800seconds答案：C69.WhichstatementdescribesBFD?A、BFDprovidesrouteloopprotection.B、BFDprovideshighavailabilitywithmultipleRoutingEngines.C、BFDprovidesbroadcaststormprotection.D、BFDrapidlydetectslinkfailures.答案：D70.WhichstatementistrueaboutGREtunnels?A、GREtunnelscanbeusedforonlyIPpackets.B、GREtunnelsensurethatapacketdoesnotliveforever.C、Packetsareencapsulatedunchangedbeforeenteringthetunnel.D、GREtunnelssupportpoint-to-multipoint.答案：C71.YouareconfiguringanewBGPservicetoyourserviceprovider.YouwanttoensurethatBGPisfullyestablishedandhasalltheroutesintheroutetablebeforeallowingtraffictotransittherouter.

Whichfeatureachievesthisrequirement?A、BGProutereflectorB、IS-ISmeshgroupC、BGPlocalpreferenceD、IS-ISoverloadbit答案：D72.YouhaveanOSPFNSSAareathatisalsoreceivingIS-ISroutesontheASBR.

Inthisscenario,whichLSAtypeisusedtoannounceexternalIS-ISroutes?A、Type1B、Type7C、Type8D、Type4答案：B73.Clicktotheexhibitbutton.Referringtotheexhibit,whichconfigurationchangeisneededforanIS-ISLevel1adjacencybetweenR1andR2?A、ConfiguretheIo0familyISOaddress49.0002.0010.0042.0002.00onR1.B、DisableLevel2onR2'sge-0/0/1interface.C、ConfiguretheIo0familyISOaddress49.0002.0010.0042.0002.00onR2.D、EnableLevel2onR1'sge-0/0/1interface.答案：C解析：Level1adjacenciescanbeformedbetweenroutersthatshareamonareanumber.WeneedtochangeISOaddressessothatbothroutershavethesameareanumber.IfwechangetheISOaddressonR249.0002.0010.0042.0002.00,bothrouterswillhave0002asareanumber.Note:Level2adjacencycanbeformedbetweenroutersthatmightormightnotshareanareanumber.Reference:http://./techpubs/en_US/junos16.1/topics/example/isis-multi-level.html74.ClicktheExhibitbutton.YouhavecreatedaGREtunnelasshowninexhibit.Therouterwithtunnelendpoint