Specifications

Configuring NetFlow on the Enterasys S-Series, N-Series, and K-Series Modules
May 18, 2011 Page 6 of 21
• Examiningflowsbypriority
•Characterizingtrafficutilizationbydevice
• Examiningtheamountoftrafficperport
Configuring NetFlow on the Enterasys S-Series, N-Series, and
K-Series Modules
TheS‐Series,N‐Series(Gold,Platinum,andDiamond),andK‐SeriesmodulesallsupportNetFlow.
NetFlowisdisabledbydefaultonalldevicesatdevicestartup.
ThissectioncoversthefollowingNetFlowconfigurationtopics:
• EnterasysNetFlowImplementation
• ConfiguringtheActiveFlowExportTimer
• ConfiguringtheNetFlowCollectorIPAddress
• Configuring
theNetFlowExportVersion
• ConfiguringNetFlowExportVersionRefresh
• ConfiguringaNetFlowPort
• ConfiguringtheNetFlowCache
• DisplayingNetFlowConfigurationandStatistics
Enterasys NetFlow Implementation
TheS‐Series,N‐Series,andK‐Seriesarchitecturesprovideapowerfulmechanismforcollecting
networkflowstatistics,withreportingcapacitythatscaleswiththeadditionofeachmodule.For
eachflow,packetandbytecountstatisticsarecollectedbythemodule’sforwardinghardware.The
flowreportgenerationlogicisdistributed,
permittingeachmoduletoreportflowsonitsown
ports.
TheNetFlowimplementationenablesthecollectionofNetFlowdataonbothswitchedandrouted
frames,allowingmodulesinallareasofanetworkinfrastructuretocollectandreportflowdata.
RoutingdoesnotneedtobeenabledtoutilizeNetFlow
datacollection.Flowdetaildependsonthe
contentoftheframeandthepaththeframetakesthroughtheswitch.
NetFlowcanbeenabledonallportsonasystem,includingfixedfrontpanelports,LAGports,
andNEMports.RouterinterfaceswhichmaptoVLANsmaynotbeenableddirectly.
NetFlowrecordsaregeneratedonlyforflowsforwhichahardwareconnectionhasbeen
established.Aslongasthenetworkconnectionexists(andNetFlowisenabled),NetFlowrecords
willbegenerated.Flowsthatareswitchedinfirmware(softforwarded)willnothaveNetFlow
recordsreported.Forflowsthatarerouted,the
firmwarereportsthesourceanddestination
ifIndexesasthephysicalports,notroutedinterfaces.
InthecaseofaLAGport,themodule(s)thatthephysicalportsareonwillgenerateNetFlow
recordsindependently.Theywillhowever,reportthesourceifIndexastheLAGport.TheFlow
SequenceCounterfield
intheNetFlowHeaderisuniquepermodule.TheEngineIDfieldofthe
NetFlowHeaderisusedtoidentifyeachuniquemodule.
NetFlowrequiresaminimumof256MBofmemoryinallmodulesinachassisrunning5.41.xx
firmwareandabovetoenableNetFlow.