Configuring Netflow; Netflow Overview - Cisco Nexus 5600 Series Configuration Manual

Configuring NetFlow

NetFlow identifies packet flows for ingress IP packets and provides statistics based on these packet flows.
NetFlow does not require any change to either the packets themselves or to any networking device.
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NetFlow Overview

NetFlow uses flows to provide statistics for accounting, network monitoring, and network planning. A flow
is a unidirectional stream of packets that arrives on a source interface (or VLAN) and has the same values for
the keys. A key is an identified value for a field within the packet. You create a flow using a flow record to
define the unique keys for your flow.
Cisco NX-OS supports both Traditional Netflow and Flexible NetFlow.
With Traditional NetFlow all of the keys and fields that are exported must be fixed. Traditional Netflow
supports IPv4 flows only. You can choose which keys you want to use to define the flow. Each unique flow
is cached and some statistics are collected for the flow.
Flexible NetFlow enables enhanced network anomalies and security detection. Flexible NetFlow allows you
to define an optimal flow record for a particular application by selecting the keys from a large collection of
predefined fields.
OL-31641-01
NetFlow Overview, page 261
Flow Record, page 262
Flow Exporter, page 262
NetFlow Match Keys, page 262
NetFlow Collect Parameters, page 264
Sampled NetFlow, page 265
Guidelines and Limitations for NetFlow, page 265
How to Configure NetFlow, page 266
Verifying the NetFlow Configuration, page 274
Monitoring NetFlow, page 275
Configuration Examples for NetFlow, page 275
Cisco Nexus 5600 Series NX-OS System Management Configuration Guide, Release 7.x
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