Cisco CCNA Netflow Overview

NetFlow is a Cisco IOS application that provides statistics on packet flows. NetFlow is transparent to any systems and/or applications on the network.  NetFlow collects IP traffic information and allows you to easily analyze it for things such as utilized network resources, calculate what departments are charged for bandwidth utilization, capacity planning, and service/application utilization.  It has two parts, the NetFlow enabled network device and the NetFlow collector.

 

•NetFlow is an application used for collecting IP traffic
• NetFlow enables the following:
•Can measure who / what utilized network resources
•Can be used to calculate accounting and charging of resources
•Can be used for capacity planning
•Can be used to measure specific utilization by custom applications and services
•NetFlow is comprised of two components:
•NetFlow-enabled network devices
•NetFlow collector

 

Cisco CCNA Netflow Configuration

An example NetFlow configuration is displayed on the above slide.  You will need to configure the NetFlow data capture, data export and configurre the export version and stats to be analayzed.

•Steps:
•Configure NetFlow data capture
•Configure NetFlow data export
•Configure NetFlow data export version
•Verify NetFlow and its operation and statistics
Example:

Router(config)# interface Gi0/1

Router(config-if)# ip flow ingress

Router(config-if)# ip flow ingress

Router(config-if)# exit

Router(config)# flow-export destination 192.168.10.10 9996

Router(config)# flow-export version 9

Cisco CCNA NetFlow Verification

The basic commands to configure NetFlow on a Cisco device are shown above.

 

•Commands to verify NetFlow Configuration:
•show ip interface
•Used to verify if NetFlow is enabled on an interface
•show ip flow export
•Used to verify status and statistics for NetFlow accounting data export
•show ip cache flow
•Used to display a summary of NetFlow statistics within Cisco IOS