Notaios6
ios6 1 3 时间:2021-02-23 阅读:()
VistageraldosmecanismoskeepalivenoCiscoIOSndiceIntroduoInformaesdeApoioMecanismosdokeepalivedeinterfaceInterfacesdeEthernetInterfacesseriaisManutenesdeatividadedeHDLCManutenesdeatividadedePPPInterfacesdotúnelGREKeepalivescriptoKeepalivesdeIKEKeepalivesNATIntroduoEstedocumentodescreveosváriosmecanismoskeepalivenodoCiscoIOS.
InformaesdeApoioOsmensagensdekeepalivesoenviadosporumdispositivoderedeatravésdeumexameoudeunscircuitosvirtuaisafiminformaraindaumoutrodispositivoderedeesseocircuitoentreelesfunes.
ParaqueoKeepalivestrabalhehádoisfatoresessenciais:Ointervalokeepaliveéoperíododetempoentrecadamensagemdekeepalivequeéenviadoporumdispositivoderede.
Istoésempreconfigurável.
qAsnovastentativasdokeepalivesoonúmerodevezesqueodispositivocontinuaaenviarapacoteskeepalivesemrespostaantesqueoestadoestejamudadoa"parabaixo".
ParaalgunstiposdeKeepalivesistoéconfigurável,quandoparaoutrohouverumvalorpadroquenopossasermudado.
qMecanismosdokeepalivedeinterfaceInterfacesdeEthernetEmmeiosdetransmissotaiscomoumEthernet,oKeepalivesélevementeoriginal.
DesdequehámuitospossíveisvizinhosnosEthernet,okeepalivenoestáprojetadodeterminarseotrajetoaqualquerumvizinhoespecíficonofioestádisponível.
Projeta-sesomentecertificar-sedosistemalocaltenhaoacessodeleituraegravaoaofiodosEthernetpróprio.
OroteadorproduzumpacotedeEthernetcomsecomooendereoMACdeorigemededestinoeumcódigotipodeEthernetespecialde0x9000.
OhardwaredeEthernetenviaestepacotenofiodosEtherneteentorecebeimediatamenteestapartetraseiradopacoteoutravez.
IstoverificaohardwaredeemissoedereceponoadaptadordoEtherneteaintegridadebásicadofio.
InterfacesseriaisAsinterfacesserialpodemtertiposdiferentesdeencapsulamentosecadatipodeencapsulamentodeterminaotipodoKeepalivesqueseráusado.
InscrevaocomandokeepalivenomododeconfiguraodainterfaceafimajustarafrequênciaemqueumroteadorenviapacotesECHOREQaseupar:Afimrestaurarosistemaaointervalokeepalivedopadrodossegundos10,inscrevaocomandokeepalivecomnenhumapalavra-chave.
qAfimdesabilitaroKeepalives,inscrevaocomandodisabledokeepalive.
qNota:keepaliveOcomandoaplica-seàsinterfacesserialqueusamolinkdedadosdenívelelevadoContol(HDLC)ouoencapsulamentoPPP.
NoseaplicaàsinterfacesserialqueusamoEncapsulamentoframerelay.
Nota:ParaoPPPeostiposdoencapsulamentodeHDLC,umkeepalivedezerodesabilitaoKeepaliveseérelatadonocomandoshowrunning-configoutputcomoodesabilitaodokeepalive.
ManutenesdeatividadedeHDLCUmoutromecanismokeepaliveconhecidoémanutenesdeatividadeserialparaoHDLC.
AsmanutenesdeatividadeserialsoenviadasparaafrenteeparatrásentredoisRoteadoreseoKeepalivessoreconhecidos.
Comousodosnúmerosdesequênciaseguircadakeepalive,cadadispositivopodeconfirmarseéparHDLCrecebeuokeepalivequeenviou.
ParaoencapsulamentodeHDLC,trêsKeepalivesignoradosfazemcomquearelaosejaderrubada.
PermitaocomandodebugserialinterfaceparaumaconexodeHDLCafimpermitirqueousuárioveroKeepalivesqueégeradoeenviado:SampleOutput:17:21:09.
685:Serial0/0:HDLCmyseq0,mineseen0*,yourseen1,lineupAsmanutenesdeatividadedeHDLCcontêmtrêspartesafimdeterminá-lotrabalham:O"myseq"queénossopróprionúmerodeincremento.
qO"mineseen"queérealmenteumreconhecimentodooutrolado(incrementado)quedizqueesperaestenúmerodenós.
q"Yourseen"queénossoreconhecimentoaooutrolado.
qNota:Quandoadiferenanosvaloresnoscamposdomyseqedomineseenexcedetrêsnoroteador2,alinhavaiparabaixoearelaoérestaurada.
DesdequeasmanutenesdeatividadedeHDLCsotipoKeepalivesECHOREQ,afrequênciadekeepaliveéimportanteerecomenda-sequecombinamacimaexatamenteemambososlados.
Seostemporizadoressoforadasincronizao,osnúmerosdesequênciacomeamsairdaordem.
Porexemplo,sevocêajustaumladoaossegundos10eooutroa25segundos,aindapermitiráarelaopermaneaacimaenquantoadiferenanafrequêncianoésuficienteparafazercomqueosnúmerosdesequênciaestejamporumadiferenadetrês.
ComoumailustraodecomoasmanutenesdeatividadedeHDLCtrabalham,oroteador1eoroteador2soconectadosdiretamenteatravésdoSerial0/0edoSerial2/0respectivamente.
AfimilustrarcomooKeepalivesfalhadoHDCLéusadoparaseguirosestadosdarelao,oSerial0/0seráfechadonoroteador1.
Roteador1Router1#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
1/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:09.
685:Serial0/0:HDLCmyseq0,mineseen0*,yourseen1,lineup17:21:19.
725:Serial0/0:HDLCmyseq1,mineseen1*,yourseen2,lineup17:21:29.
753:Serial0/0:HDLCmyseq2,mineseen2*,yourseen3,lineup17:21:39.
773:Serial0/0:HDLCmyseq3,mineseen3*,yourseen4,lineup17:21:49.
805:Serial0/0:HDLCmyseq4,mineseen4*,yourseen5,lineup17:21:59.
837:Serial0/0:HDLCmyseq5,mineseen5*,yourseen6,lineup17:22:09.
865:Serial0/0:HDLCmyseq6,mineseen6*,yourseen7,lineup17:22:19.
905:Serial0/0:HDLCmyseq7,mineseen7*,yourseen8,lineup17:22:29.
945:Serial0/0:HDLCmyseq8,mineseen8*,yourseen9,lineupRouter1(config-if)#shut17:22:39.
965:Serial0/0:HDLCmyseq9,mineseen9*,yourseen10,lineup17:22:42.
225:%LINK-5-CHANGED:InterfaceSerial0/0,changedstatetoadministrativelydown17:22:43.
245:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial0/0,changedstatetodownRoteador2Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownManutenesdeatividadedePPPAsmanutenesdeatividadedePPPsoumpoucodiferentesdasmanutenesdeatividadedeHDLC.
AocontráriodoHDLC,asmanutenesdeatividadedePPPsomaiscomosibilos.
Osambososladospodemsibilar-seemseulazer.
OmovimentonegociadoapropriadoéresponderSEMPREaeste"sibilo".
AssimparamanutenesdeatividadedePPP,afrequênciaouovalordetemporizadorsosomentelocalmenterelevanteenotêmnenhumimpactonooutrolado.
MesmoseumladodesligaoKeepalives,aindaRESPONDER2aquelasrequisiesdeecodoladoquetemumtemporizadordekeepalive.
Contudo,nuncainiciaráalgumadoseuspróprios.
PermitaocomandodebugppppacketparaumaconexoPPPafimpermitirqueousuárioverasmanutenesdeatividadedePPPquesoenviadas:Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownerespostasquesorecebidas:Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownAsmanutenesdeatividadedePPPcontêmtrêspartes:NúmerodeID-usadoparaidentificaraqueoECHOREQoparresponde.
qTipokeepalive-OECHOREQéKeepalivesenviadopelodispositivodeorigemeoqECHOREPérespostasenviadaspelopar.
Númerosmágicos-asnotificaesincluemosnúmerosmágicosdoserveredoclienteremoto.
OparvalidaonúmeromágiconopacotederequisiodeecoLCP,etransmiteopacotederespostadeecocorrespondenteLCPquecontémonúmeromágiconegociadopeloroteador.
qParaoencapsulamentoPPP,cincoKeepalivesignoradosfazemcomquearelaosejaderrubadaInterfacesdotúnelGREOmecanismokeepalivedotúnelGREélevementediferentedoqueparaEthernetouinterfacesserial.
DáacapacidadeparaqueumladoorigineerecebapacoteskeepaliveaedeumroteadorremotomesmoseoroteadorremotonoapoiamanutenesdeatividadedeGRE.
DesdequeoGREéummecanismodetunelamentodopacoteparaescavarumtúneloIPdentrodoIP,umpacotedotúnelIPGREpodeserconstruídodentrodeumoutropacotedotúnelIPGRE.
ParamanutenesdeatividadedeGRE,asPRE-construesdoremetenteopacotedarespostadekeepalivedentrodopacotederequisiodokeepaliveoriginaldemodoqueasnecessidadesdaextremidaderemotasomentedefazerodesencapsulamentoGREpadrodocabealhoIPexteriorGREeenviamentoopacoteGREinternoIP.
Estemecanismofazcomquearespostadekeepaliveenvieparaforaainterfacefísicaumpoucodoqueainterfacedetúnel.
ParamaisdetalhesaotrabalhardoKeepalivesdotúnelGRE,vejacomoasmanutenesdeatividadedeGREtrabalham.
KeepalivescriptoKeepalivesdeIKEOKeepalivesdoInternetKeyExchange(IKE)éummecanismousadoparadeterminarseumparVPNpodeascendenteereceberotráfegocriptografado.
OKeepalivescriptoseparadoéexigidoalémdoquekeepalivesdeinterfaceporqueosparesVPNgeralmentesoconectadosnuncadevoltaàpartetraseira,assimqueoskeepalivesdeinterfacenofornecembastanteinformaosobreoestadodoparVPN.
EmdispositivosIOSCisco,oskeepalivesdeIKEsopermitidospelousodeummétodoproprietáriochamadooDeadPeerDetection(DPD).
AfimpermitirqueogatewayenvieDPDaopar,incorporeestecomandoaomododeconfiguraoglobal:cryptoisakmpkeepaliveseconds[retry-seconds][periodic|on-demand]AfimdesabilitaroKeepalives,use"no"oformuláriodestecomando.
Paraobtermaisinformaessobredoquecadapalavra-chavenestecomandofaz,vejaokeepalivecriptodoisakmp.
Paramaisgranularidade,oKeepalivespodeigualmenteserconfiguradosoboperfilISAKMP.
Paramaisdetalhes,vejao[CiscoIOSIPsec]davistageraldoperfilISAKMP.
KeepalivesNATEmcasodasencenaesondeumparVPNestáatrásdeumNetworkAddressTranslation(NAT),NAT-Traversaléusadoparaacriptografia.
Contudo,duranteperíodosociososépossívelqueaentradaNATnodispositivoascendentepdecronometrarparafora.
IstopodecausarproblemasquandovocêtrazacimaotúneleoNATnoébidirecional.
OKeepalivesNATépermitidoafimmanterotraodinmicoNATvivoduranteumaconexoentredoispares.
OKeepalivesNATépacotesdeUDPcomumpayloadunencrypteddeumbyte.
EmboraaaplicaoatualDPDsejasimilaraoKeepalivesNAT,háumapequenadiferena-oDPDestáusadoparadetectarostatusdepeerquandooKeepalivesNATforenviadoseaentidadedoIPsecnoenviounemrecebeuopacoteemumperíododetempoespecificado.
Ointervaloválidoestáentre5a3600segundos.
Dica:SeoKeepalivesNATestápermitido(atravésdocomandokeepalivenatdoisamkpcripto),osusuáriosdevemassegurar-sedequeovalorinativosejamaiscurtodoqueotempodeexpiraodomapeamentoNATde20segundos.
Paraobtermaisinformaessobredestacaracterística,vejaatransparênciadeNATdoIPsec.
InformaesdeApoioOsmensagensdekeepalivesoenviadosporumdispositivoderedeatravésdeumexameoudeunscircuitosvirtuaisafiminformaraindaumoutrodispositivoderedeesseocircuitoentreelesfunes.
ParaqueoKeepalivestrabalhehádoisfatoresessenciais:Ointervalokeepaliveéoperíododetempoentrecadamensagemdekeepalivequeéenviadoporumdispositivoderede.
Istoésempreconfigurável.
qAsnovastentativasdokeepalivesoonúmerodevezesqueodispositivocontinuaaenviarapacoteskeepalivesemrespostaantesqueoestadoestejamudadoa"parabaixo".
ParaalgunstiposdeKeepalivesistoéconfigurável,quandoparaoutrohouverumvalorpadroquenopossasermudado.
qMecanismosdokeepalivedeinterfaceInterfacesdeEthernetEmmeiosdetransmissotaiscomoumEthernet,oKeepalivesélevementeoriginal.
DesdequehámuitospossíveisvizinhosnosEthernet,okeepalivenoestáprojetadodeterminarseotrajetoaqualquerumvizinhoespecíficonofioestádisponível.
Projeta-sesomentecertificar-sedosistemalocaltenhaoacessodeleituraegravaoaofiodosEthernetpróprio.
OroteadorproduzumpacotedeEthernetcomsecomooendereoMACdeorigemededestinoeumcódigotipodeEthernetespecialde0x9000.
OhardwaredeEthernetenviaestepacotenofiodosEtherneteentorecebeimediatamenteestapartetraseiradopacoteoutravez.
IstoverificaohardwaredeemissoedereceponoadaptadordoEtherneteaintegridadebásicadofio.
InterfacesseriaisAsinterfacesserialpodemtertiposdiferentesdeencapsulamentosecadatipodeencapsulamentodeterminaotipodoKeepalivesqueseráusado.
InscrevaocomandokeepalivenomododeconfiguraodainterfaceafimajustarafrequênciaemqueumroteadorenviapacotesECHOREQaseupar:Afimrestaurarosistemaaointervalokeepalivedopadrodossegundos10,inscrevaocomandokeepalivecomnenhumapalavra-chave.
qAfimdesabilitaroKeepalives,inscrevaocomandodisabledokeepalive.
qNota:keepaliveOcomandoaplica-seàsinterfacesserialqueusamolinkdedadosdenívelelevadoContol(HDLC)ouoencapsulamentoPPP.
NoseaplicaàsinterfacesserialqueusamoEncapsulamentoframerelay.
Nota:ParaoPPPeostiposdoencapsulamentodeHDLC,umkeepalivedezerodesabilitaoKeepaliveseérelatadonocomandoshowrunning-configoutputcomoodesabilitaodokeepalive.
ManutenesdeatividadedeHDLCUmoutromecanismokeepaliveconhecidoémanutenesdeatividadeserialparaoHDLC.
AsmanutenesdeatividadeserialsoenviadasparaafrenteeparatrásentredoisRoteadoreseoKeepalivessoreconhecidos.
Comousodosnúmerosdesequênciaseguircadakeepalive,cadadispositivopodeconfirmarseéparHDLCrecebeuokeepalivequeenviou.
ParaoencapsulamentodeHDLC,trêsKeepalivesignoradosfazemcomquearelaosejaderrubada.
PermitaocomandodebugserialinterfaceparaumaconexodeHDLCafimpermitirqueousuárioveroKeepalivesqueégeradoeenviado:SampleOutput:17:21:09.
685:Serial0/0:HDLCmyseq0,mineseen0*,yourseen1,lineupAsmanutenesdeatividadedeHDLCcontêmtrêspartesafimdeterminá-lotrabalham:O"myseq"queénossopróprionúmerodeincremento.
qO"mineseen"queérealmenteumreconhecimentodooutrolado(incrementado)quedizqueesperaestenúmerodenós.
q"Yourseen"queénossoreconhecimentoaooutrolado.
qNota:Quandoadiferenanosvaloresnoscamposdomyseqedomineseenexcedetrêsnoroteador2,alinhavaiparabaixoearelaoérestaurada.
DesdequeasmanutenesdeatividadedeHDLCsotipoKeepalivesECHOREQ,afrequênciadekeepaliveéimportanteerecomenda-sequecombinamacimaexatamenteemambososlados.
Seostemporizadoressoforadasincronizao,osnúmerosdesequênciacomeamsairdaordem.
Porexemplo,sevocêajustaumladoaossegundos10eooutroa25segundos,aindapermitiráarelaopermaneaacimaenquantoadiferenanafrequêncianoésuficienteparafazercomqueosnúmerosdesequênciaestejamporumadiferenadetrês.
ComoumailustraodecomoasmanutenesdeatividadedeHDLCtrabalham,oroteador1eoroteador2soconectadosdiretamenteatravésdoSerial0/0edoSerial2/0respectivamente.
AfimilustrarcomooKeepalivesfalhadoHDCLéusadoparaseguirosestadosdarelao,oSerial0/0seráfechadonoroteador1.
Roteador1Router1#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
1/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:09.
685:Serial0/0:HDLCmyseq0,mineseen0*,yourseen1,lineup17:21:19.
725:Serial0/0:HDLCmyseq1,mineseen1*,yourseen2,lineup17:21:29.
753:Serial0/0:HDLCmyseq2,mineseen2*,yourseen3,lineup17:21:39.
773:Serial0/0:HDLCmyseq3,mineseen3*,yourseen4,lineup17:21:49.
805:Serial0/0:HDLCmyseq4,mineseen4*,yourseen5,lineup17:21:59.
837:Serial0/0:HDLCmyseq5,mineseen5*,yourseen6,lineup17:22:09.
865:Serial0/0:HDLCmyseq6,mineseen6*,yourseen7,lineup17:22:19.
905:Serial0/0:HDLCmyseq7,mineseen7*,yourseen8,lineup17:22:29.
945:Serial0/0:HDLCmyseq8,mineseen8*,yourseen9,lineupRouter1(config-if)#shut17:22:39.
965:Serial0/0:HDLCmyseq9,mineseen9*,yourseen10,lineup17:22:42.
225:%LINK-5-CHANGED:InterfaceSerial0/0,changedstatetoadministrativelydown17:22:43.
245:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial0/0,changedstatetodownRoteador2Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownManutenesdeatividadedePPPAsmanutenesdeatividadedePPPsoumpoucodiferentesdasmanutenesdeatividadedeHDLC.
AocontráriodoHDLC,asmanutenesdeatividadedePPPsomaiscomosibilos.
Osambososladospodemsibilar-seemseulazer.
OmovimentonegociadoapropriadoéresponderSEMPREaeste"sibilo".
AssimparamanutenesdeatividadedePPP,afrequênciaouovalordetemporizadorsosomentelocalmenterelevanteenotêmnenhumimpactonooutrolado.
MesmoseumladodesligaoKeepalives,aindaRESPONDER2aquelasrequisiesdeecodoladoquetemumtemporizadordekeepalive.
Contudo,nuncainiciaráalgumadoseuspróprios.
PermitaocomandodebugppppacketparaumaconexoPPPafimpermitirqueousuárioverasmanutenesdeatividadedePPPquesoenviadas:Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownerespostasquesorecebidas:Router2#showinterfacesserial0/0/0Serial0/0/0isup,lineprotocolisup(connected)HardwareisHD64570Internetaddressis10.
0.
0.
2/8MTU1500bytes,BW64Kbit,DLY20000usec,rely255/255,load1/255EncapsulationHDLC,loopbacknotset,keepaliveset(10sec)[outputisomited]17:21:04.
929:Serial2/0:HDLCmyseq0,mineseen0,yourseen0,lineup17:21:14.
941:Serial2/0:HDLCmyseq1,mineseen1*,yourseen1,lineup17:21:24.
961:Serial2/0:HDLCmyseq2,mineseen2*,yourseen2,lineup17:21:34.
981:Serial2/0:HDLCmyseq3,mineseen3*,yourseen3,lineup17:21:45.
001:Serial2/0:HDLCmyseq4,mineseen4*,yourseen4,lineup17:21:55.
021:Serial2/0:HDLCmyseq5,mineseen5*,yourseen5,lineup17:22:05.
041:Serial2/0:HDLCmyseq6,mineseen6*,yourseen6,lineup17:22:15.
061:Serial2/0:HDLCmyseq7,mineseen7*,yourseen7,lineup17:22:25.
081:Serial2/0:HDLCmyseq8,mineseen8*,yourseen8,lineup17:22:35.
101:Serial2/0:HDLCmyseq9,mineseen9*,yourseen9,lineup17:22:45.
113:Serial2/0:HDLCmyseq10,mineseen10*,yourseen10,lineup17:22:55.
133:Serial2/0:HDLCmyseq11,mineseen10,yourseen10,lineup17:23:05.
153:HD(0):Resetfrom0x20375817:23:05.
153:HD(0):AssertingDTR17:23:05.
153:HD(0):AssertingDTRandRTS17:23:05.
153:Serial2/0:HDLCmyseq12,mineseen10,yourseen10,lineup17:23:15.
173:HD(0):Resetfrom0x20375817:23:15.
173:HD(0):AssertingDTR17:23:15.
173:HD(0):AssertingDTRandRTS17:23:15.
173:Serial2/0:HDLCmyseq13,mineseen10,yourseen10,linedown17:23:16.
201:%LINEPROTO-5-UPDOWN:LineprotocolonInterfaceSerial2/0,changedstatetodownRouter2#17:23:25.
193:Serial2/0:HDLCmyseq14,mineseen10,yourseen10,linedownAsmanutenesdeatividadedePPPcontêmtrêspartes:NúmerodeID-usadoparaidentificaraqueoECHOREQoparresponde.
qTipokeepalive-OECHOREQéKeepalivesenviadopelodispositivodeorigemeoqECHOREPérespostasenviadaspelopar.
Númerosmágicos-asnotificaesincluemosnúmerosmágicosdoserveredoclienteremoto.
OparvalidaonúmeromágiconopacotederequisiodeecoLCP,etransmiteopacotederespostadeecocorrespondenteLCPquecontémonúmeromágiconegociadopeloroteador.
qParaoencapsulamentoPPP,cincoKeepalivesignoradosfazemcomquearelaosejaderrubadaInterfacesdotúnelGREOmecanismokeepalivedotúnelGREélevementediferentedoqueparaEthernetouinterfacesserial.
DáacapacidadeparaqueumladoorigineerecebapacoteskeepaliveaedeumroteadorremotomesmoseoroteadorremotonoapoiamanutenesdeatividadedeGRE.
DesdequeoGREéummecanismodetunelamentodopacoteparaescavarumtúneloIPdentrodoIP,umpacotedotúnelIPGREpodeserconstruídodentrodeumoutropacotedotúnelIPGRE.
ParamanutenesdeatividadedeGRE,asPRE-construesdoremetenteopacotedarespostadekeepalivedentrodopacotederequisiodokeepaliveoriginaldemodoqueasnecessidadesdaextremidaderemotasomentedefazerodesencapsulamentoGREpadrodocabealhoIPexteriorGREeenviamentoopacoteGREinternoIP.
Estemecanismofazcomquearespostadekeepaliveenvieparaforaainterfacefísicaumpoucodoqueainterfacedetúnel.
ParamaisdetalhesaotrabalhardoKeepalivesdotúnelGRE,vejacomoasmanutenesdeatividadedeGREtrabalham.
KeepalivescriptoKeepalivesdeIKEOKeepalivesdoInternetKeyExchange(IKE)éummecanismousadoparadeterminarseumparVPNpodeascendenteereceberotráfegocriptografado.
OKeepalivescriptoseparadoéexigidoalémdoquekeepalivesdeinterfaceporqueosparesVPNgeralmentesoconectadosnuncadevoltaàpartetraseira,assimqueoskeepalivesdeinterfacenofornecembastanteinformaosobreoestadodoparVPN.
EmdispositivosIOSCisco,oskeepalivesdeIKEsopermitidospelousodeummétodoproprietáriochamadooDeadPeerDetection(DPD).
AfimpermitirqueogatewayenvieDPDaopar,incorporeestecomandoaomododeconfiguraoglobal:cryptoisakmpkeepaliveseconds[retry-seconds][periodic|on-demand]AfimdesabilitaroKeepalives,use"no"oformuláriodestecomando.
Paraobtermaisinformaessobredoquecadapalavra-chavenestecomandofaz,vejaokeepalivecriptodoisakmp.
Paramaisgranularidade,oKeepalivespodeigualmenteserconfiguradosoboperfilISAKMP.
Paramaisdetalhes,vejao[CiscoIOSIPsec]davistageraldoperfilISAKMP.
KeepalivesNATEmcasodasencenaesondeumparVPNestáatrásdeumNetworkAddressTranslation(NAT),NAT-Traversaléusadoparaacriptografia.
Contudo,duranteperíodosociososépossívelqueaentradaNATnodispositivoascendentepdecronometrarparafora.
IstopodecausarproblemasquandovocêtrazacimaotúneleoNATnoébidirecional.
OKeepalivesNATépermitidoafimmanterotraodinmicoNATvivoduranteumaconexoentredoispares.
OKeepalivesNATépacotesdeUDPcomumpayloadunencrypteddeumbyte.
EmboraaaplicaoatualDPDsejasimilaraoKeepalivesNAT,háumapequenadiferena-oDPDestáusadoparadetectarostatusdepeerquandooKeepalivesNATforenviadoseaentidadedoIPsecnoenviounemrecebeuopacoteemumperíododetempoespecificado.
Ointervaloválidoestáentre5a3600segundos.
Dica:SeoKeepalivesNATestápermitido(atravésdocomandokeepalivenatdoisamkpcripto),osusuáriosdevemassegurar-sedequeovalorinativosejamaiscurtodoqueotempodeexpiraodomapeamentoNATde20segundos.
Paraobtermaisinformaessobredestacaracterística,vejaatransparênciadeNATdoIPsec.
ReliableSite怎么样，月付$95美国洛杉矶独立服务器
ReliableSite怎么样？ReliableSite好不好。ReliableSite是一家成立于2006年的老牌美国商家，主要经营美国独立服务器租赁，数据中心位于：洛杉矶、迈阿密、纽约，带宽1Gbps起步，花19美元/月即可升级到10Gbps带宽，月流量150T足够各种业务场景使用，且免费提供20Gbps DDoS防护。当前商家有几款大硬盘美国独服，地点位于美国洛杉矶或纽约机房，机器配置很具有...
justhost：“第4次VPS测评”，8.3元/月，200M带宽，不限流量，KVM虚拟，4个俄罗斯机房应有适合你的
justhost.ru官方来消息说已经对网络进行了比较全面的优化，针对中国电信、联通、移动来说，4个机房总有一个适合中国用户，让站长进行一下测试，这不就有了这篇有关justhost的VPS的第四次测评。本帖主要关注的是网络，对于其他的参数一概不管！ 官方网站：https://justhost.ru 最低配VPS：8.3元/月，KVM，512M内存，5G硬盘，200M带宽，不限流量 购买链接：...
CloudServer：$4/月KVM-2GB/50GB/5TB/三个数据中心
CloudServer是一家新的VPS主机商，成立了差不多9个月吧，提供基于KVM架构的VPS主机，支持Linux或者Windows操作系统，数据中心在美国纽约、洛杉矶和芝加哥机房，都是ColoCrossing的机器。目前商家在LEB提供了几款特价套餐，最低月付4美元(或者$23.88/年)，购买更高级别套餐还能三个月费用使用6个月，等于前半年五折了。下面列出几款特别套餐配置信息。CPU：1cor...
ios6 1 3为你推荐
-
推广方法现在最常用的推广方式有哪几种flash导航条FLASH导航条 怎么加入链接？百度手写百度为什么没有了在线手写输入法今日热点怎么删除youku今日热点怎么卸载办公协同软件oa办公系统软件有哪些童之磊网文大学很强吗？iphone6上市时间苹果6是什么时候出的 ？电子商务网站模板我想开发一个电子商务网站，但是想加入自己设计的模板，可以吗？如何清理ie缓存怎么清除IE缓存freebsd安装虚拟机vmware7的安装和FreeBSD的安装