Cisco Switches with IPDT Cause Duplicate IPs

Run these two commands to completely disable the ip device tracking function on the affected Cisco switches that have this IOS bug. Youarehere: CiscoSwitcheswithIPDTCauseDuplicateIPs Problem: Allen-BradleyEthernetmodulefaultingwiththefollowingscrollingmessage: Module#1: 1756-ENBT/A [IPAddress] Message: DuplicateIP 84b51768b631 PLCconnectedtoaCisco3850 Cause IOS BugonCiscoswitches(e.g.IE300,C3850,C3650)Seehttps://bst.cloudapps.cisco.com/bugsearch/bug/CSCuj04986   Solution: RunthesetwocommandstocompletelydisabletheipdevicetrackingfunctionontheaffectedCiscoswitchesthathavethisIOSbug Hostname(configif)#nmspattachsuppress Hostname(configif)#noipdevicetrackingmax Or followtheworkaroundsbelowdependingonyourfirmwareversion FullCiscoArticle 568750FalseDuplicateIPdetectiononEthernetmoduleswhenusedwithCiscoswitches Problem WhenRockwellAutomationEtherNet/IPmodulesareconnectedtoasubnetcontainingCiscoswitcheswith"IPdevicetracking"(IPDT)enabled,themodulesmaygointoaduplicateIPaddressstateafterarestart/reset. Environment AnylayertwonetworksthatcontainbothRockwellAutomationEtherNet/IPmodulesandCiscoswitchesrunningIPDT. IPDTismuchmorelikelytobeimplementedonCiscoswitchesasofAugust,2013becauseofabehaviorchangewhichenablesthiscommandifanyfeaturewhichrequiresitisenabled. ThisbehaviorchangealsoremovestheabilitytoturnoffIPDTwithoutfirstturningoffanyfeatureswhichrequireIPDT.TheStratixlineofswitcheswillnothave“IPdevicetracking”enabledbydefaultuntilapermanentsolutionisinplace. Cause TheIPDTfeaturesendsprobeARPpacketswithasourceIPaddressof0.0.0.0.,thesourceMACIDoftheswitch,andthetargetIPandMACIDforthedevicebeingprobedtocheckthatitisstillconnectedandresponsive. Whenadevicebecomesdisconnected,andthenisreconnectedwithintheconfigurableIPDTtimeoutperiod,probeARPpacketsmaybereceivedbyaLogixEthernetmoduleatthesametimeasitisinitsAddressConflictDetectionmechanism.Ifthishappens,theEtherNet/IPmodulewillimmediatelygointoaduplicateIPstate,andstopcommunicating. IPDTwhenactivatedonaCiscoswitchwilltrytoprobeforeveryIPconnectedonthesubnet,regardlessofwhetheritisconnectedtothatswitchornot. TestinghasshownthatthisaffectsthemajorityofEthernetmodulessoldbyRockwellAutomation. Solution Ciscoiscontinuallyupdatingthelatestworkarounds. HereisalinktoCisco’stechnote: http://www.cisco.com/c/en/us/support/docs/ip/address-resolution-protocol-arp/118630-technote-ipdt-00.html Workaround Severalworkaroundstothisissueexist.TheyallmakesuggestionsusingCiscoIOScommandlineinterfacecommands. Workaround1 Architectmanufacturingzonesubnetssuchthat: 1.IPDTisexplicitlydisabledoneverytrunkportwiththefollowingcommand: Hostname(configif)# ipdevicetrackingmaximum0 2.IPDTprobedelayismanuallyconfiguredonanyaccessportconnectedtoaRockwellAutomationEthernetmodulewiththefollowingcommand: Hostname(config)#ipdevicetrackingprobedelay10 Workaround2 IftheswitchinquestionhasanadministrationIP(SVI)configuredonthesubnet/VLANinquestiontheCiscoCLIcommand: Hostname(config)#ipdevicetrackingprobeusesvi willinserttheadministrationIPintothesourceIPintheIPDTpacket.ThispacketwillnotimpactAddressConflictDetectionoperation. Workaround3 DisableIPDTonanyCiscoswitchportswithIPDTenabledthatsubsequentlyconnecttoaRockwellAutomationEthernetmodulewiththefollowingcommand: Hostname(configif)# ipdevicetrackingmaximum0   Workaround4 Runboththetrackingprobeauto-sourcecommandandthetrackingprobeauto-sourcefallbackonallswitcheswiththisfeatureturnedon. Seehttps://www.cisco.com/c/en/us/support/docs/ip/address-resolution-protocol-arp/118630-technote-ipdt-00.html AdditionalLinks IPDTOverview-https://www.cisco.com/c/en/us/support/docs/ip/address-resolution-protocol-arp/118630-technote-ipdt-00.html CiscoCommunityDiscussion-https://supportforums.cisco.com/discussion/12563251/cisco-switch-upgrade-leads-allen-bradley-plc-duplicate-ip-address-errors HoneywellCommunityDiscussion-https://dashboard.intelligrated.com/knowledgebase/PrintArticle.aspx?article=59affed0-03ec-4c12-a40c-2a14f43fc5d3 WhereToBuy:FindaDistributorNearMe   [email protected]     SUPPORTLINKS IntraVUELatestOnlineHelp| Clickhere IntraVUEDownloads,Reports,ReleaseNotes,Videos,Help| Clickhere IntraVUE Resources| Clickhere IntraVUE ProductOffering|  Clickhere IntraVUERequestaDemo|  Clickhere IntraVUESolutionsKnowledgeBase|  Clickhere IntraVUE3Videos|  IntraVUEVideosinYouTube PRODUCTINFORMATION IntraVUE™Software LastUpdate:06/07/2018 Copyright©2018 PanduitCorp IntraVUE™GlobalTechSupport +1-800-777-3300 [email protected] COMPANYINFORMATION PanduitCorp 18900PanduitDr. TinleyPark,IL 60487 www.panduit.com CustomerService 1-800-777-3300 [email protected]   Opentopicwithnavigation