Random Sampled Flow

Random Sampled Flow

• Netflow provides highly granular per-flow traffic statistics in a Cisco router
• a flow is unidirectional set of packets that arrive at the router on the same subinterface, have the same source  and destination ip address, layer 4 protocol the same source and destination  part.
• router accumulates Netflow statistics  in Netflow cache and can export them to an external device i.e Cisco CNS Netflow collection engine for further processing.

Defining a Netflow Sampler Map

Summary Steps

1) enable

2) configure terminal

3) flow-sampler-map

4) mode random on-out-of

5) end

show flow-sampler

displays  attributes  (including mode, sampling rate and number of sampled packets)  of one of all Random Sampled Netflow samplers.

show ip  cache verbose flow

displays additional Netflow fields in the header  when Random Sampled Netflow is  configured.