Verifying and Using NetFlow

Once configured, you should verify NetFlow works, and then you can start using the collected data. The ultimate verification of NetFlow is to examine the information stored on the NetFlow collector itself, but you can also check the local NetFlow cache on a router directly, proving that the router is at least collecting the data. You do so with the show ip cache flow command shown in Example 19-7.

Example 19-7 Examining the NetFlow Cache

R1# show ip cache flowIP packet size distribution (255 total packets):   1-32   64   96  128  160  192  224  256  288  320  352  384  416  448  480   .000 .000 .000 1.00 .000 .000 .000 .000 .000 .000 .000 .000 .000 .000 .000    512  544  576 1024 1536 ...

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