Introduction
This document provides sample configuration of Flexible NetFlow using IPv6 in Cisco IOS routers.Cisco IOS Flexible NetFlow is a next-generation flow technology.
NetFlow is a Cisco IOS technology that provides statistics on packets flowing through a router. NetFlow provides IP operational data from IP networks to support network and security monitoring, network planning and other variety of purposes.
Flexible NetFlow customize the traffic analysis parameters for your specific requirements and with the help of reusable configuration components, it facilitates the creation of more complex configurations for traffic analysis and data export.Flexible NetFlow improves on original NetFlow by providing
enhanced optimization of the network infrastructure, improves capacity planning and security detection.
Prerequisite
The following prerequisite to be met for configuring IPv6 NetFlow:
- The networking device must be configured for IPv6 routing.
- IPv6 CEF or Distributed IPv6 CEF must be enabled on the routers and on any interfaces on which you want to enable Flexible NetFlow.
Background
In this example, router R1 and R2 are connected via FastEthernet interface Fa1/0 and uses OSPFv3 to communicate with each other. The interfaces are configured with IPv6 addresses.
Note: All configuration is tested on Cisco 7200 Series Router running on IOS Version 15.0(1)M Advance IP Services Image.
Topology Diagram
Summary Steps
In Global Configuration Mode
- enable
- configure terminal
- flow monitor monitor-name
- description description
- record
- end
In Interface Configuration Mode
- ipv6 flow monitor monitor-name {input |output}
- end
Configuration
R1
R2
R1#show run ! version 15.0 ! hostname R1 ! flow monitor TEST Creates a flow monitor and enters Flexible NetFlow flow monitor configuration mode. record netflow ipv6 original-output Specifies the record for the flow monitor. ! ipv6 unicast-routing ipv6 cef ! interface Loopback0 no ip address ipv6 address 1111::11/128 ipv6 ospf 1 area 0 ! interface FastEthernet1/0 no ip address duplex auto speed auto ipv6 address 2020:1:1:1::1/64 ipv6 ospf 1 area 0 ipv6 flow monitor TEST output Activates the flow monitor that you created previously by assigning it to the interface to analyze egress traffic. ! ipv6 router ospf 1 router-id 1.1.1.1 log-adjacency-changes ! end | R2#show run ! version 15.0 ! hostname R2 ! flow monitor TEST2 record netflow ipv6 protocol-port Creates flows based on protocols and ports in the traffic flow data. ! ipv6 unicast-routing ipv6 cef ! interface Loopback0 no ip address ipv6 address 2222::22/128 ipv6 ospf 1 area 0 ! interface FastEthernet1/0 no ip address duplex auto speed auto ipv6 address 2020:1:1:1::2/64 ipv6 ospf 1 area 0 ipv6 flow monitor TEST2 input Activates the flow monitor that you created previously by assigning it to the interface to analyze egress traffic. ! ! ipv6 router ospf 1 router-id 2.2.2.2 log-adjacency-changes ! ! end |
Verification Commands
show flow monitor
show running-config flow monitor <monitor-name>
show flow monitor <monitor-name> statistics
show flow record netflow ipv6 protocol-port
show flow monitor <monitor-name> cache
References
Understanding IPv6 NetFlow
Flexible Netflow Configuration Guide, Cisco IOS Release 15.0S
Cisco IOS Flexible NetFlow Command Reference
Cisco IOS Flexible NetFlow Technology Q&A