Cisco Systems OL-6900-01 manual What Is CNS NetFlow Collection Engine?

Chapter 1 Overview

What Is CNS NetFlow Collection Engine?

Caution Throughout this publication there are numerous examples of CNS NetFlow Collection Engine input commands and output results. Included are examples of IP addresses. Be aware that IP address examples are not usable IP addresses. The examples do not represent real-life configurations.

What Is CNS NetFlow Collection Engine?

CNS NetFlow Collection Engine provides fast, scalable, and economical data collection from multiple export devices exporting NetFlow data records. Figure 1-1 shows an example of a typical NetFlow data export scheme. In it, various export devices send export data to user-specified CNS NetFlow Collection Engine UDP ports.

Figure 1-1 CNS NetFlow Collection Engine Overview

Switch 1

Router A Router B Router C

Exported NetFlow data

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CNS NetFlow Collection

Engine workstation

Each of the export devices in this example is configured for NetFlow data export. Part of the configuration information for each export device includes the IP address and the UDP port number (a logical port designator) that identify CNS NetFlow Collection Engine as the receiver of flows from this export device. The UDP port number is a user-configurable designator: you can configure CNS NetFlow Collection Engine to listen for flows on a number of different UDP ports, and then configure your export devices so that each device exports flows to a dedicated UDP port, or have a number of devices export flows to the same, shared UDP port.

After you configure and start CNS NetFlow Collection Engine, it listens to the user-specified UDP ports for exported flows from the export devices you have configured for NetFlow data export.

CNS NetFlow Collection Engine performs the following functions:

•NetFlow data collection from multiple export devices

•Reduction in data volume through filtering and aggregation

•Hierarchical data storage (helps client applications retrieve data)

•File system space management

Cisco CNS NetFlow Collection Engine User Guide, Release 5.0.2

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