CDP Command Reference - Cisco

1 CDP Command ReferenceThis chapterdescribescommandsused to monitorthe router and networkusing Cisco DiscoveryProtocol(CDP). cdp enable,page 2 cdp run, page 3 show cdp, page 4 show cdp entry, page 5 show cdp interface,page 7 show cdp neighbors,page 8 show cdp traffic, page 10 Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01) 78-20604-031cdp enableTo enable Cisco DiscoveryProtocol(CDP) on an interface,use thecdpenablecommandin interfaceconfigurationmode. To disableCDP on an interface,use thenoform of this cdpenableSyntax DescriptionThis commandhas no argumentsor DefaultEnabledat the global level and on all the ModesInterfaceconfiguration(config-if)Co mmand HistoryModificationReleaseThis commandwas GuidelinesCDP is enabledby defaultat the global level and on each supportedinterfaceto send or followingexampleshows how to disableCDP only on the TenGigabitEthernet4 #configterminalRouter(config)#interfaceT enGigabitEthernet4/1 Router(config-if)#no cdp enableRelated CommandsDescriptionCommandReenablesCDP on a Cisco Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01)

2 278-20604-03 CDP Command Referencecdp enablecdp runTo enable the CDP, use thecdpruncommandin global configurationmode. To disableCDP, use thenoform of this cdprunSyntax DescriptionThis commandhas no argumentsor DefaultEnabledat the global level and on all the ModesGlobalconfiguration(config) Command HistoryModificationReleaseThis commandwas GuidelinesCDP is enabledby defaultat the global level and on each supportedinterfaceto send or ,youcannotenableitoneachinterfaceusingth ecdpenableinterfaceconfigurationmode followingexampleshows how to enable CDP on the TenGigabitEthernet4/1interface,when CDP (config)#no cdp runRouter(config)#endRouter#showcdp% CDP is not enabledRouter#configureterminalEnterconf igurationcommands,one per (config)#interfaceTenGigabitEthernet4/1 Router(config-if)

3 #cdp enable% CannotenableCDP on thisinterface,sinceCDP is not runningRouter(config-if)#Related CommandsDescriptionCommandEnablesCDP on a CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01) 78-20604-033 CDP Command Referencecdp runshow cdpTo displayglobal CDP information,includingtimer and hold-timeinformation,use theshowcdpcommandin privilegedEXEC DescriptionThis commandhas no argumentsor ModesPrivilegedEXEC (#) Command HistoryModificationReleaseThis commandwas (thedefaultsettingforcdptimer).Alsoshown isthatthecurrentrouterdirectsits neighborsto hold its CDP advertisementsfor 3 minutes(the defaultforcdpholdtime), and thatthe router is enabledto transmitCDP version2 #showcdpGlobalCDP information:SendingCDP packetsevery60 secondsSendinga holdtimevalueof 180 secondsSendingCDPv2advertisementsis enabledRelated CommandsDescriptionCommandDisplaysinform ationaboutaspecificneighbordevicelisted in the CDP the interfaceson whichCDP is neighboringdevicesdiscoveredusing informationfrom the CDP Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01)478-20604-03 CDP Command Referenceshow cdpshow cdp entryTo displayinformationabout a specificneighboringdevice discoveredusing CDP, use theshowcdpentrycommandin privilegedEXEC {*|entry-name[protocol|version]}Syntax DescriptionWildcardshowingall the CDP neighbors.

4 *Name of the can enter an asterisk(*) at the end of anentry-name, such asshowcdpentrydev*,whichwouldshowinforma tionabouttheneighbor, (Optional)Limits the displayto informationabout the protocolsenabledon (Optional)Limitsthedisplaytoinformationa bouttheversionofsoftwarerunningon the ModesPrivilegedEXEC (#) Command HistoryModificationReleaseThis commandwas followingis sampleoutput from informationabout theprotocolsenabledon #showcdp :IP CommandsDescriptionCommandDisplaysglobal CDP information,includingtimerand CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01) 78-20604-035 CDP Command Referenceshow cdp entryDescriptionCommandDisplaysinformati onabout the interfaceson whichCDP is neighboringdevicesdiscoveredusing informationfrom the CDP Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01)678-20604-03 CDP Command Referenceshow cdp entryshow cdp interfaceTo displayinformationabout the interfaceson which CDP is enabled,use theshowcdpinterfacecommandin privilegedEXEC [typenumber]Syntax Description(Optional)Type of (Optional)Numberof the ModesPrivilegedEXEC (#)

5 Command HistoryModificationReleaseThis commandwas #showcdp interfaceTenGigabitEthernet4/1 TenGigabitEthernet4/1is up, lineprotocolis upEncapsulationARPAS endingCDP packetsevery60 secondsHoldtimeis 180 secondsRelated CommandsDescriptionCommandDisplaysinform ationaboutaspecificneighbordevicelisted in the CDP CDP information,includingtimerand neighboringdevicesdiscoveredusing informationfrom the CDP CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01) 78-20604-037 CDP Command Referenceshow cdp interfaceshow cdp neighborsTodisplaydetailedinformationabo utneighboringdevicesdiscoveredusingCDP,u setheshowcdpneighborscommandin privilegedEXEC [typenumber] [detail]Syntax Description(Optional)Type of the interfaceconnectedto the (Optional)Numberof the interfaceconnectedto the (Optional)Displaysdetailedinformationabo utaneighbor(orneighbors)includingnetwork address,enabledprotocols,hold time, and ModesPrivilegedEXEC (#) Command HistoryModificationReleaseThis commandwas followingexampleis sampleoutput from #showcdp neighborsCapabilityCodes.

6 R - Router,T - TransBridge,B - SourceRouteBridgeS - Switch,H - Host,I - IGMP,r - Repeater,P - Phone,D - Remote,C - CVTA,M - Two-portMac 37/3176R I CPT 600 Gig 36 37/1174R I CPT 600 Gig 36 36/41134R I CPT 600 Gig 37 36/43134R I CPT 600 Gig 37 3/2132R I CPT 600 Ten 4 4/2174R I CPT 600 Ten 3/2 TheDeviceIDcolumnintheoutputindicatesthe remotenodeIDandthePortIDcolumnindicatest heremoteport. Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01)878-20604-03 CDP Command Referenceshow cdp neighborsRelated CommandsDescriptionCommandDisplaysinform ationaboutaspecificneighbordevicelisted in the CDP the interfaceson whichCDP is CDP information,includingtimerand informationfrom the CDP CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01) 78-20604-039 CDP Command Referenceshow cdp neighborsshow cdp trafficTodisplayinformationabouttrafficb etweendevicesgatheredusingCDP,usetheshow cdptrafficcommandin privilegedEXEC DescriptionThis commandhas no argumentsor ModesPrivilegedEXEC (#)

7 Command HistoryModificationReleaseThis commandwas #showcdp trafficTotalpacketsoutput:543,Input:333 Hdr syntax:0, Chksumerror:0, Encapsfailed:0No memory:0, Invalid:0, Fragmented:0 CDP version1 advertisementsoutput:191,Input:187 CDP version2 advertisementsoutput:352,Input:146 Related CommandsDescriptionCommandDisplaysinform ationaboutaspecificneighbordevicelisted in the CDP the interfaceson whichCDP is CDP information,includingtimerand neighboringdevicesdiscoveredusing Cisco CPT Command Reference guide CTC and Documentation Release and Cisco IOS Release (01)1078-20604-03 CDP Command Referenceshow cdp traffic