Zte ZXR10 2928E-PS User Manual

Chapter4ServiceConguration
Switch2(cfg)#showloopdetect
Theblock-delayofloopdetect:5(min)
Thepacketintervalofloopdetect:15(sec)
PortIdisUpisStpisProtectisExtendloopVlanNumloopType
----------------------------------------------------
1UpNoYesYes1Port
2UpNoYesNo0Port
4.37UDLDConguration
UDLDOverview
UniDirectionalLinkDetection(UDLD)isaLayer2logicallinkdetectionprotocol.Itcan
detectlogicalconnectivityofEthernetlinksandverifyphysicalconnectivity.Differentfrom
physicalconnectivitydetection,UDLDisneighbor-baseddetection.Layer1devicesare
transparentforUDLD.
UDLDneedstoestablishneighborrelationshipbetweenLayer2devicesrst.Whenthe
UDLDfunctionisenabledonanEthernetportwhosestatusisup,theportsendsaProbe
messageinvitinganeighbordevicetojoin.TheportonwhichtheUDLDfunctionisenabled
ontheneighbordevicereceivestheProbemessageandsendsanEchomessage.Ifthe
portreceivestheEchomessage,theconnectionbetweenthedevicesworksproperlyin
bothdirectionsintheviewofthelocaldevice.Neighborrelationshipisestablishedwith
thepeerdeviceonthelocaldevice.ThelocaldevicessendsanEchomessage.Afterthe
peerdevicereceivestheEchomessage,theneighborrelationshipisestablishedbetween
thedevices.
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,thedevicedoesnotoperatestheport.
lInaggressivemode,ifthedevicecannotconrmthatthelinkisworkingproperlyin
bothdirections(suchasthelinkisconnectedincorrectly,thelinkisworkingproperly
onlyinonedirectionorthelinkisaself-loop),theportisshutdown.Itisnecessaryto
usetheresetorrecoverycommandtorecoverthecommunicationabilityoftheport.
Generally,UDLDshutsdownaportinthefollowingsituations.
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SJ-20120409144109-002|2012-07-02(R1.0)ZTEProprietaryandCondential

Zte ZXR10 2928E-PS Specifications

General

Brand	Zte
Model	ZXR10 2928E-PS
Category	Switch
Language	English