1.Whichtwostatementsarecorrectaboutreflectinginet-vpnunicastprefixesinBGProutereflection? (Choosetwo)
A.RoutereflectorsdonotchangeanyexistingBGPattributesbydefaultwhenadvertisingroutes. BABGPpeerdoesnotrequireanyconfigurationchangestobecomearoutereflectorclient CClientsaddtheiroriginatorIDwhenadvertisingroutestotheirroutereflector DRoutereflectorsaddtheirclusterIDtotheASpathwhenreadvertisingclientroutes
Answer:A,B
Explanation:
RoutereflectionisaBGPfeaturethatallowsaroutertoreflectrouteslearnedfromoneIBGPpeerto anotherIBGPpeer,withoutrequiringafull-meshIBGPtopologyRoutereflectorsdonotchangeany existingBGPattributesbydefaultwhenadvertisingroutes,unlessexplicitlyconfiguredtodosoABGP peerdoesnotrequireanyconfigurationchangestobecomearoutereflectorclient,onlytheroutereflector needstobeconfiguredwiththeclientparameterunder[editprotocolsbgpgroupgroup-nameneighbor neighbor-address]hierarchylevel.
ClicktheExhibitbutton-Referringtotheexhibit,whichtwostatementsarecorrectaboutBGProuteson R3thatarelearnedfromtheISP-Aneighbor?(Choosetwo)
ABydefault,thenext-hopvaluefortheseroutesisnotchangedbyISP-AbeforebeingsenttoR3
BTheBGPlocal-preferencevaluethatisusedbyISP-AisnotadvertisedtoR3
CAllBGPattributevaluesmustberemovedbeforereceivingtheroutes
DThenext-hopvaluefortheseroutesischangedbyISP-AbeforebeingsenttoR3
Answer:A,B
Explanation:
BGPisanexteriorgatewayprotocolthatusespathvectorroutingtoexchangeroutinginformationamong autonomoussystems.BGPusesvariousattributestoselectthebestpathtoeachdestinationandto propagateroutingpoliciesSomeofthecommonBGPattributesareASpath,nexthop,localpreference, MED,origin,weight,andcommunityBGPattributescanbeclassifiedintofourcategories:well-known mandatory,well-knowndiscretionary,optionaltransitive,andoptionalnontransitiveWell-known mandatoryattributesareattributesthatmustbepresentineveryBGPupdatemessageandmustbe recognizedbyeveryBGPspeakerWell-knowndiscretionaryattributesareattributesthatmayormaynot bepresentinaBGPupdatemessagebutmustberecognizedbyeveryBGPspeakerOptionaltransitive attributesareattributesthatmayormaynotbepresentinaBGPupdatemessageandmayormaynotbe recognizedbyaBGPspeakerIfanoptionaltransitiveattributeisnotrecognizedbyaBGPspeaker,itis passedalongtothenextBGPspeaker.Optionalnontransitiveattributesareattributesthatmayormay notbepresentinaBGPupdatemessageandmayormaynotberecognizedbyaBGPspeakerIfan optionalnontransitiveattributeisnotrecognizedbyaBGPspeaker,itisnotpassedalongtothenextBGP speakerInthisquestion,wehavefourrouters(R1,R2,R3,andR4)thatareconnectedinafullmesh topologyandrunningIBGP.R3receivesthe192.168.0.0/16routefromitsEBGPneighborandadvertises ittoR1andR4withdifferentBGPattributevaluesWeareaskedwhichstatementsarecorrectaboutthe BGProutesonR3thatarelearnedfromtheISP-Aneighbor.
Basedontheinformationgiven,wecaninferthatthecorrectstatementsare:
✑Bydefault,thenext-hopvaluefortheseroutesisnotchangedbyISP-AbeforebeingsenttoR3Thisis becausethedefaultbehaviorofEBGPistopreservethenext-hopattributeoftheroutesreceivedfrom anotherEBGPneighborThenext-hopattributeindicatestheIPaddressoftherouterthatshouldbeused asthenexthoptoreachthedestinationnetwork
✑TheBGPlocal-preferencevaluethatisusedbyISP-AisnotadvertisedtoR3Thisisbecausethe local-preferenceattributeisawell-knowndiscretionaryattributethatisusedtoinfluencetheoutbound trafficfromanautonomoussystemThelocal-preferenceattributeisonlypropagatedwithinan autonomoussystemandisnotadvertisedtoexternalneighbors
References:
https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13753-25.html: https://wwwciscocom/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13762-40html: https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/13759-37.html
3.Apacketisreceivedonaninterfaceconfiguredwithtransmissionscheduling.Oneoftheconfigured queues
Inthisscenario,whichtwoactionswillbetakenbydefaultonaJunosdevice?(Choosetwo.)
ATheexcesstrafficwillbediscarded
BTheexceedingqueuewillbeconsideredtohavenegativebandwidthcredit
CTheexcesstrafficwillusebandwidthavailablefromotherqueueses
DTheexceedingqueuewillbeconsideredtohavepositivebandwidthcredit
Answer:A,B
Explanation:
TransmissionschedulingisaCoSfeaturethatallowsyoutoallocatebandwidthamongdifferentqueues onaninterfaceEachqueuehasaconfiguredbandwidthpercentagethatdetermineshowmuchofthe availablebandwidthitcanuseIfaqueueexceedsitsallocatedbandwidth,itisconsideredtohave
DownloadthelatestJN0-664dumpstohelpyoupassyourexameasily
negativebandwidthcreditanditsexcesstrafficwillbediscardedbydefault.Ifaqueuedoesnotuseallof itsallocatedbandwidth,itisconsideredtohavepositivebandwidthcreditanditsunusedbandwidthcan besharedbyotherqueues.
4WhichtwostatementsarecorrectaboutVPLStunnels?(Choosetwo)
ALDP-signaledVPLStunnelsonlysupportcontrolbit0
BLDP-signaledVPLStunnelsuseauto-discoverytoprovisionsites
CBGP-signaledVPLStunnelscanuseeitherRSVPorLDPbetweenthePErouters
DBGP-signaledVPLStunnelsrequiremanualprovisioningofsites
Answer:B,C
Explanation:
VPLSisaLayer2VPNtechnologythatallowsmultiplesitestoconnectoverasharedIP/MPLSnetwork asiftheywereonthesameLANVPLStunnelscanbesignaledusingeitherLabelDistributionProtocol (LDP)orBorderGatewayProtocol(BGP).LDP-signaledVPLStunnelsuseauto-discoverytoprovision sites,meaningthatPErouterscanautomaticallydiscoverotherPEroutersthatbelongtothesameVPLS instance
ThenetworkshownintheexhibitisbasedonIS-IS Whichstatementiscorrectinthisscenario?
ATheNSELbyteforArea0001is00
BTheareaaddressistwobytes
CTheroutersareusingunnumberedinterfaces
DThesystemIDofR12is192168161
Answer:A
Explanation:
IS-ISisaninteriorgatewayprotocolthatuseslink-stateroutingtoexchangeroutinginformationamong routerswithinasingleautonomoussystemIS-ISusestwotypesofaddressestoidentifyroutersand areas:systemIDandareaaddressThesystemIDisauniqueidentifierforeachrouterinanIS-IS domainThesystemIDis6octetslongandcanbederivedfromtheMACaddressormanuallyconfigured Theareaaddressisavariable-lengthidentifierforeachareainanIS-ISdomainTheareaaddresscanbe 1to13octetslongandiscomposedofhigh-orderoctetsoftheaddressAnIS-ISinstancemaybe assignedmultipleareaaddresses,whichareconsideredsynonymousMultiplesynonymousarea addressesareusefulwhenmergingorsplittingareasinthedomain1Inthisquestion,wehaveanetwork basedonIS-ISwithfourrouters(R11,R12,R21,andR22)belongingtoarea0001Thearea addressforarea0001is49.0001.TheNSELbyteforarea0001isthelastoctetoftheaddress,whichis 01TheNSELbytestandsforNetworkServiceAccessPointSelector(NSAPSelector)andindicatesthe typeofservicerequestedfromthenetworklayer2.Therefore,thecorrectstatementinthisscenarioisthat theNSELbyteforarea0001is01
References:
1:
https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iprouteisis/configuration/xe-16/irs-xe-16-book/irs-ovrv w-cfhtml
2:
https://wwwjunipernet/documentation/us/en/software/junos/is-is/topics/concept/is-is-routing-overviewht ml
Referringtotheexhibit,CE-1isprovidingNATservicesforthehostsatSite1andyoumustprovide Internetaccessforthosehosts
Whichtwostatementsarecorrectinthisscenario?(Choosetwo)
AYoumustconfigureastaticrouteinthemainroutinginstanceforthe10120/24prefixthatusesthe VPN-Ainet0tableasthenexthop
BYoumustconfigureastaticrouteinthemainroutinginstanceforthe20301131/32prefixthatuses theVPN-Ainet0tableasthenexthop
C.YoumustconfigureaRIBgrouponPE-1toleakadefaultroutefromtheinet.0tabletothe
VPN-Ainet0table
D.YoumustconfigureaRIBgrouponPE-1toleakthe1012.0/24prefixfromtheVPN-A.inet.0tableto theinet0table
Answer:A,B
Explanation:
ToprovideInternetaccessforthehostsatSite1,youneedtoconfigurestaticroutesinthemainrouting instanceonPE-1thatpointtotheVPN-Ainet0tableasthenexthopThisallowsPE-1toforwardtraffic fromtheInternettoCE-1usingMPLSlabelsandviceversaYouneedtoconfiguretwostaticroutes:one forthe10120/24prefixthatrepresentstheprivatenetworkofSite1,andoneforthe20301131/32 prefixthatrepresentsthepublicIPaddressofCE-1
7WhichthreemechanismsareusedbyJunosplatformstoevaluateincomingtrafficforCoSpurposes? (Choosethree)
Arewriterules
B.behavioraggregateclassifiers
Ctrafficshapers
D.fixedclassifiers
Emultifieldclassifiers
Answer:B,D,E
Explanation:
JunosplatformsusedifferentmechanismstoevaluateincomingtrafficforCoSpurposes,suchas:
✑Behavioraggregateclassifiers:Theseclassifiersuseasinglefieldinapacketheadertoclassifytraffic intodifferentforwardingclassesandlossprioritiesbasedonpredefinedoruser-definedvalues
✑Fixedclassifiers:Theseclassifiersuseafixedfieldinapacketheadertoclassifytrafficintodifferent forwardingclassesandlossprioritiesbasedonpredefinedvalues
✑Multifieldclassifiers:Theseclassifiersusemultiplefieldsinapacketheadertoclassifytrafficinto differentforwardingclassesandlossprioritiesbasedonuser-definedvaluesandfilters
RewriterulesandtrafficshapersarenotusedtoevaluateincomingtrafficforCoSpurposes,butratherto modifyorshapeoutgoingtrafficbasedonCoSpolicies
8Exhibit
YouareaskedtoexchangeroutesbetweenR1andR4asshownintheexhibitThesetworoutersusethe sameASnumber
Whichtwostepswillaccomplishthistask?(Choosetwo)
AConfiguretheBGPgroupwiththeadvertise-peer-asparameteronR1andR4
BConfiguretheBGPgroupwiththeas-overrideparameteronR2andR3
CConfiguretheBGPgroupwiththeadvertise-peer-asparameteronR2andR3
DConfiguretheBGPgroupwiththeas-overrideparameteronR1andR4
Answer:A,B
Explanation:
Theadvertise-peer-asparameterallowsaroutertoadvertiseitspeer’sASnumberaspartoftheASpath attributewhensendingBGPupdatestootherpeers.Thisparameterisusefulwhentworoutersinthe sameASneedtoexchangeroutesthroughanotherAS,suchasinthecaseofR1andR4Byconfiguring thisparameteronR1andR4,theycanadvertiseeachother’sASnumbertoR2andR3,respectively Theas-overrideparameterallowsaroutertoreplacetheASnumberofitspeerwithitsownASnumber whenreceivingBGPupdatesfromthatpeerThisparameterisusefulwhentworoutersindifferentASes needtoexchangeroutesthroughanotherASthathasthesameASnumberasoneofthem,suchasin thecaseofR2andR3ByconfiguringthisparameteronR2andR3,theycanoverridetheASnumberof R1andR4withtheirownASnumberwhensendingBGPupdatestoeachother
9.YouwanttoensurethatL1IS-ISroutershaveonlythemostspecificroutesavailablefromL2IS-IS routers
Whichactionaccomplishesthistask?
AConfiguretheignore-attached-bitparameteronallL2routers
B.Configureallrouterstoallowwidemetrics.
CConfigureallrouterstobeL1
D.Configuretheignore-attached-bitparameteronallL1routers
Answer:D
Explanation:
TheattachedbitisaflaginanIS-ISLSPthatindicateswhetherarouterisconnectedtoanotherareaor level(L2)ofthenetworkBydefault,L2routerssetthisbitwhentheyadvertisetheirLSPstoL1routers, andL1routersusethisbittoselectadefaultroutetoreachotherareasorlevelsthroughL2routers However,thismayresultinsuboptimalroutingiftherearemultipleL2routerswithdifferentpathstoother areasorlevelsToensurethatL1routershaveonlythemostspecificroutesavailablefromL2routers, youcanconfiguretheignore-attached-bitparameteronallL1routersThismakesL1routersignorethe