Zte ZXR10 5250-52TC - UDLD Configuration

Chapter5ServiceConguration
Switch2(cfg)#setloopdetectport1,2enable
Switch2(cfg)#setloopdetectextendport1enable
lCongurationVerication
Checktheloopdetectionstateofswitch2.
Switch2(cfg)#showloopdetect
Theblock-delayofloopdetect:5(min)
Thepacketintervalofloopdetect:15(sec)
PortIdisUpisStpisProtectisExtendloopVlanNumloopType
----------------------------------------------------
1UpNoYesYes1Port
2UpNoYesNo0Port
5.36UDLDConguration
UDLDOverview
UniDirectionalLinkDetection(UDLD)isaLayer2logicallinkdetectionprotocol.Itcan
detectlogicalconnectivityofEthernetlinksandverifyphysicalconnectivity.Differentfrom
physicalconnectivitydetection,UDLDisneighbor-baseddetection.Layer1devicesare
transparentforUDLD.
UDLDneedstoestablishneighborrelationshipbetweenLayer2devicesrst,Aport
supportsamaximumnumberof12neighbors.WhentheUDLDfunctionisenabledon
anEthernetportwhosestatusisup,theportsendsaProbemessageinvitinganeighbor
devicetojoin.TheportonwhichtheUDLDfunctionisenabledontheneighbordevice
receivestheProbemessageandsendsanEchomessage.IftheportreceivestheEcho
message,theconnectionbetweenthedevicesworksproperlyinbothdirectionsinthe
viewofthelocaldevice.Neighborrelationshipisestablishedwiththepeerdeviceonthe
localdevice.ThelocaldevicessendsanEchomessage.Afterthepeerdevicereceives
theEchomessage,theneighborrelationshipisestablishedbetweenthedevices.
Afterneighborrelationshipisestablished,thedevicessendHellomessagesperiodically
todetectwhetherthelinkisoperatingproperly.WhenreceivingaHellomessagefromthe
neighbor,adeviceupdatestheneighborinformationsavedlocallyandresetsthetime-out
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
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SJ-20131111172707-002|2013-11-27(R1.0)ZTEProprietaryandCondential