Zte ZXR10 2900E Series - Page 189

Chapter5ServiceConguration
periodoftheneighbor.IfthedevicedoesnotreceivesaHellomessagewhenthetime-out
periodexpires,itisconsideredthattheafaultoccurstotheneighborandtheneighboris
aged.Ifthelastneighborisdeletedduetoaging,itisconsideredthatthelinkisnotin
normaloperatingstate.Itisnecessarytohandletheproblemaccordingtoworkingmode.
TherearetwoUDLDworkingmodes:normalmodeandaggressivemode.
lInnormalmode,onlywhenthedevicereceivesaprotocolmessageconrmingthat
thelinkisconnectedincorrectlywilltheportbeshutdown.Ifthedevicedoesnot
receivetherelatedmessageorcannotconrmthatthelinkisworkingproperlyinone
direction,thedevicedoesnotoperatetheport.
lInaggressivemode,ifthedevicecannotconrmthatthelinkisworkingproperlyin
bothdirections(suchasthelinkisconnectedincorrectly,thelinkisworkingproperly
onlyinonedirectionorthelinkisaself-loop),theportisshutdown.Itisnecessaryto
usetheresetorrecoverycommandtorecoverthecommunicationabilityoftheport.
UDLDshutsdownaportinthefollowingsituations.
lInbothmodes,whenanEchomessageissent,thedevicedetectsthattheneighbor
ofthepeerportisnotthedeviceitselfduringthenalneighbordetection.
lInaggressivemode,thestatusbecomesPROBEbecausethelastneighborisaged,
andmultipleProbemessagesaresentcontinuouslywithoutanyresponse.
lInaggressivemode,theportreceivestheUDLDmessagesentbyitselfandthereis
aself-loop.
Topreventaneighborfrombeingagedbymistake,alocaldevicesendsFlushmessages
onitsowninitiativetotheportonwhichtheUDLDfunctionisenabledinthefollowing
situations.
lTheportisdownadministratively.
lUDLDisdownontheport.
lThedeviceisrestarted.
ConguringUDLD
TheUDLDcongurationincludesthefollowingcommands:
CommandFunction
zte(cfg)#udldport<portlist>{enable|disable}EnablesordisablesUDLDona
port.
zte(cfg)#udldport<portlist>mode{aggressive|normal}SetsthemodeofaportinUDLD.
zte(cfg)#udldport<portlist>messagetimer<7-90>Setstheintervalofsending
messagesafterUDLDentersthe
BiDirectionalstatusandtheportis
steady.
zte(cfg)#udldport<portlist>recovery{enable|disable}EnablesordisablestheUDLD
recoveryfunction.
zte(cfg)#udldport<portlist>recoverytimer<10-600>Setstherecoveryinterval.
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SJ-20130731155059-002|2013-11-27(R1.0)ZTEProprietaryandCondential