Hybrid or Native w RA

Document created by Stuart_Weenig on Jul 5, 2012Last modified by Melissa Potvin on Jun 15, 2014
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Parent Page: How to enable Netflow

A Catalyst 6500 in Native mode provides the best NetFlow data because it correlates the switch port information to the VLAN information. For sizing purposes, this means that the customer only needs to count the VLANs on the switch toward the total interface count. Only the L3 interfaces will be shown in ReporterAnalyzer. It is normal for L2 interfaces not to show even if they are checked in the NetFlow Manager.

A Catalyst 6500 in Hybrid mode provides NetFlow data but does not correlate the switch port information to the VLAN information. For sizing purposes, this means that the customer must count both the VLANs and the individual switch ports toward the total interface count. Either Native or Hybrid mode will work with NetFlow, but the number of interfaces monitored is drastically increased in Hybrid mode, as each individual switch port will appear in ReporterAnalyzer.

NOTE:  Prior to IOS 12.2, CEF is globally disabled by default.  In order to receive valid NetFlow data, CEF should be enabled globally by using the command ip cef in global configuration mode.

NOTE:  NetFlow is not necessary to be configured on loopback interfaces as no routed traffic should be passing on that interface type.

NOTE:  Due to configuration combinations and assuming you have followed and applied all necessary NetFlow configuration statements below, some NetFlow statistics will show far less data than it should.  There is an undocumented, unofficial command to bypass hardware caching and export directly from memory by using no mls nde direct export.  Consult with Cisco prior to implementing to ensure this will not cause problems with your configuration!

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