Configuring Data Export for Flexible NetFlow with Flow Exporters

Last Updated: November 7, 2011

This document contains information about and instructions for configuring flow exporters to export Flexible NetFlow data to remote systems such as a UNIX server running NetFlow collector.

NetFlow is a Cisco IOS technology that provides statistics on packets flowing through the router. NetFlow is the standard for acquiring IP operational data from IP networks. NetFlow provides data to support network and security monitoring, network planning, traffic analysis, and IP accounting.

Flexible NetFlow improves on original NetFlow by adding the capability to customize the traffic analysis parameters for your specific requirements. Flexible NetFlow facilitates the creation of more complex configurations for traffic analysis and data export through the use of reusable configuration components.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the Feature Information Table at the end of this document.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Prerequisites for Data Export for Flexible NetFlow with Flow Exporters

  • You are familiar with the information in the "Cisco IOS Flexible NetFlow Overview" module.
  • The networking device must be running a Cisco IOS or Cisco IOS XE release that supports Flexible NetFlow.

IPv4 Traffic

  • The networking device must be configured for IPv4 routing.
  • One of the following must be enabled on your router and on any interfaces on which you want to enable Flexible NetFlow: Cisco Express Forwarding or distributed Cisco Express Forwarding.

IPv6 Traffic

  • The networking device must be configured for IPv6 routing.
  • One of the following must be enabled on your router and on any interfaces on which you want to enable Flexible NetFlow: Cisco Express Forwarding IPv6 or distributed Cisco Express Forwarding.

Restrictions for Data Export for Flexible NetFlow with Flow Exporters

  • The NetFlow Version 5 export protocol that was first shipped in Cisco IOS Release 12.4(22)T is supported only for flow monitors that use the Flexible NetFlow predefined records (netflow-original, original input, and original output).

Information About Data Export for Flexible NetFlow with Flow Exporters

Flow Exporters

Flow exporters are created as separate components in a router's configuration. Exporters are assigned to flow monitors to export the data from the flow monitor cache to a remote system such as a NetFlow collector. Flow monitors can support more than one exporter. Each exporter can be customized to meet the requirements of the flow monitor or monitors in which it is used and the NetFlow collector systems to which it is exporting data.

Benefits of Flexible NetFlow Flow Exporters

Flexible NetFlow allows you to configure many different flow exporters, depending on your requirements. Some of the benefits of Flexible NetFlow flow exporters are as follows:

  • Using flow exporters, you can create an exporter for every type of traffic that you want to analyze so that you can send each type of traffic to a different NetFlow collector. Original NetFlow sends the data in a cache for all of the analyzed traffic to a maximum of two export destinations.
  • Flow exporters support up to ten exporters per flow monitor. Original NetFlow is limited to only two export destinations per cache.
  • Flow exporters can use both TCP and UDP for export.
  • In Cisco IOS Release 12.4(20)T and later releases, flow exporters can use class of service (CoS) in the packets that are sent to export destinations to help ensure that the packets are given the correct priority throughout the network. Original NetFlow exporters do not use CoS in the packets that are sent to export destinations.
  • In Cisco IOS Release 12.4(20)T and later releases, flow exporter traffic can be encrypted.

How to Configure Data Export for Flexible NetFlow with Flow Exporters

The tasks in this section explain how to export the data that is collected by Flexible NetFlow to a remote system for further analysis and storage.

Flow exporters are used to send the data that you collect with Flexible NetFlow to a remote system such as a NetFlow collector. Flow exporters use UDP as the transport protocol.

Restrictions

Each flow exporter supports only one destination. If you want to export the data to multiple destinations, you must configure multiple flow exporters and assign them to the flow monitor. Flow exporters are added to flow monitors to enable data export from the flow monitor cache.


Note
Only the keywords and arguments required for the Flexible NetFlow commands used in these tasks are explained in these tasks. For information about the other keywords and arguments available for these Flexible NetFlow commands, refer to the Cisco IOS Flexible NetFlow Command Reference .

To configure data export for Flexible NetFlow, perform the tasks in this section:

Configuring the Flow Exporter

To configure the flow exporter, perform the following required task.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    flow exporter exporter-name

4.    description description

5.    destination {ip-address | hostname} [vrf vrf-name]

6.    export-protocol {netflow-v5| netflow-v9}

7.    dscp dscp

8.    source interface-type interface-number

9.    option {exporter-stats | interface-table | sampler-table| vrf-table} [timeout seconds]

10.    output-features

11.    template data timeout seconds

12.    transport udp udp-port

13.    ttl seconds

14.    end

15.    show flow exporter exporter-name

16.    show running-config flow exporter exporter-name


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
flow exporter exporter-name


Example:

Router(config)# flow exporter EXPORTER-1

 

Creates the flow exporter and enters Flexible NetFlow flow exporter configuration mode.

  • This command also allows you to modify an existing flow exporter.
 
Step 4
description description


Example:

Router(config-flow-exporter)# description Exports to the datacenter

 

(Optional) Configures a description to the exporter that will appear in the configuration and the display of the show flow exporter command.

 
Step 5
destination {ip-address | hostname} [vrf vrf-name]


Example:

Router(config-flow-exporter)# destination 172.16.10.2

 

Specifies the IP address or hostname of the destination system for the exporter.

 
Step 6
export-protocol {netflow-v5| netflow-v9}


Example:

Router(config-flow-exporter)# export-protocol netflow-v9

 

Specifies the version of the NetFlow export protocol used by the exporter.

  • Default: netflow-v9.
 
Step 7
dscp dscp


Example:

Router(config-flow-exporter)# dscp 63

 

(Optional) Configures differentiated services code point (DSCP) parameters for datagrams sent by the exporter.

  • The range for the dscp argument is from 0 to 63. Default: 0.
 
Step 8
source interface-type interface-number


Example:

Router(config-flow-exporter)# source ethernet 0/0

 

(Optional) Specifies the local interface from which the exporter will use the IP address as the source IP address for exported datagrams.

 
Step 9
option {exporter-stats | interface-table | sampler-table| vrf-table} [timeout seconds]


Example:

Router(config-flow-exporter)# option exporter-stats timeout 120

 

(Optional) Configures options data parameters for the exporter.

  • You can configure all three options concurrently.
  • The range for the seconds argument is 1 to 86,400. Default: 600.
 
Step 10
output-features


Example:

Router(config-flow-exporter)# output-features

 

(Optional) Enables sending export packets using quality of service (QoS) and encryption.

 
Step 11
template data timeout seconds


Example:

Router(config-flow-exporter)# template data timeout 120

 

(Optional) Configure resending of templates based on a timeout.

  • The range for the seconds argument is 1 to 86400 (86400 seconds = 24 hours).
 
Step 12
transport udp udp-port


Example:

Router(config-flow-exporter)# transport udp 650

 

Specifies the UDP port on which the destination system is listening for exported datagrams.

  • The range for the udp-port argument is from 1 to 65536.
 
Step 13
ttl seconds


Example:

Router(config-flow-exporter)# ttl 15

 

(Optional) Configures the time-to-live (TTL) value for datagrams sent by the exporter.

  • The range for the seconds argument is from 1 to 255.
 
Step 14
end


Example:

Router(config-flow-exporter)# end

 

Exits flow exporter configuration mode and returns to privileged EXEC mode.

 
Step 15
show flow exporter exporter-name


Example:

Router# show flow exporter FLOW_EXPORTER-1

 

(Optional) Displays the current status of the specified flow exporter.

 
Step 16
show running-config flow exporter exporter-name


Example:

Router# show running-config flow exporter FLOW_EXPORTER-1

 

(Optional) Displays the configuration of the specified flow exporter.

 

Configuring and Enabling Flexible NetFlow with Data Export

You must create a flow monitor to configure the types of traffic for which you want to export the cache data. You must enable the flow monitor by applying it to at least one interface to start exporting data. To configure and enable Flexible NetFlow with data export, perform this required task.

Each flow monitor has a separate cache assigned to it. Each flow monitor requires a record to define the contents and layout of its cache entries. The record format can be one of the predefined record formats, or an advanced user may create his or her own record format using the collect and matchcommands in Flexible NetFlow flow record configuration mode.


Note

You must remove a flow monitor from all of the interfaces to which you have applied it before you can modify the record format of the flow monitor.

When you specify the "NetFlow original," or the "NetFlow IPv4 original input," or the "NetFlow IPv6 original input" predefined record for the flow monitor to emulate original NetFlow, the flow monitor can be used only for analyzing input (ingress) traffic.

When you specify the "NetFlow IPv4 original output" or the "NetFlow IPv6 original output" predefined record for the flow monitor to emulate the Egress NetFlow Accounting feature, the flow monitor can be used only for analyzing output (egress) traffic.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    flow monitor monitor-name

4.    record {record-name | netflow-original | netflow {ipv4 | ipv6 record [peer] }]

5.    exporter exporter-name

6.    exit

7.    interface type number

8.    {ip | ipv6} flow monitor monitor-name {input | output}

9.    end

10.    show flow monitor [[name] monitor-name [cache [format {csv | record | table}]][statistics]]


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
flow monitor monitor-name


Example:

Router(config)# flow monitor FLOW-MONITOR-1

 

Creates a flow monitor and enters Flexible NetFlow flow monitor configuration mode.

  • This command also allows you to modify an existing flow monitor.
 
Step 4
record {record-name | netflow-original | netflow {ipv4 | ipv6 record [peer] }]


Example:

Router(config-flow-monitor)# record netflow ipv4 original-input

 

Specifies the record for the flow monitor.

 
Step 5
exporter exporter-name


Example:

Router(config-flow-monitor)# exporter EXPORTER-1

 

Specifies the name of an exporter that you created previously.

 
Step 6
exit


Example:

Router(config-flow-monitor)# exit

 

Exits Flexible NetFlow flow monitor configuration mode and returns to global configuration mode.

 
Step 7
interface type number


Example:

Router(config)# interface ethernet 0/0

 

Specifies an interface and enters interface configuration mode.

 
Step 8
{ip | ipv6} flow monitor monitor-name {input | output}

Example:

Router(config-if)# ip flow monitor FLOW-MONITOR-1 input

 

Activates the flow monitor that you created previously by assigning it to the interface to analyze traffic.

 
Step 9
end


Example:

Router(config-if)# end

 

Exits interface configuration mode and returns to privileged EXEC mode.

 
Step 10
show flow monitor [[name] monitor-name [cache [format {csv | record | table}]][statistics]]


Example:

Router# show flow monitor FLOW-MONITOR-2 cache

 

(Optional) Displays the status and statistics for a Flexible NetFlow flow monitor. This will verify data export is enabled for the flow monitor cache.

 

Configuration Examples for Flexible NetFlow Data Export with Flow Exporters

Example Configuring Multiple Export Destinations

The following example shows how to configure multiple export destinations for Flexible NetFlow for IPv4 and IPv6 traffic.

This sample starts in global configuration mode:

!
flow exporter EXPORTER-1
 destination 172.16.10.2
 transport udp 90
 exit
!
flow exporter EXPORTER-2
 destination 172.16.10.3
 transport udp 90
 exit
!
flow monitor FLOW-MONITOR-1
 record netflow ipv4 original-input
 exporter EXPORTER-2
 exporter EXPORTER-1
!
!
flow monitor FLOW-MONITOR-2
 record netflow ipv6 original-input
 exporter EXPORTER-2
 exporter EXPORTER-1
!
ip cef
!
interface Ethernet 0/0
 ip address 172.16.6.2 255.255.255.0
 ipv6 address 2001:DB8:2:ABCD::2/48
 ip flow monitor FLOW-MONITOR-1 input
 ipv6 flow monitor FLOW-MONITOR-2 input
!

The following display output shows that the flow monitor is exporting data to the two exporters:

Router# show flow monitor FLOW-MONITOR-1
Flow Monitor FLOW-MONITOR-1:
  Description:       User defined
  Flow Record:       netflow original-input
  Flow Exporter:     EXPORTER-1
                     EXPORTER-2
  Cache:
    Type:              normal
    Status:            allocated
    Size:              4096 entries / 311316 bytes
    Inactive Timeout:  15 secs
    Active Timeout:    1800 secs
    Update Timeout:    1800 secs

Example Configuring Sending Export Packets Using QoS

The following example shows how to enable quality of service (QoS) on Flexible Netflow export packets.


Note
The Flexible NetFlow export packets are transmitted using QoS on Ethernet interface 0/1 (the interface on which the destination is reachable) to the destination host (IP address 10.0.1.2).

This sample starts in global configuration mode:

!
flow record FLOW-RECORD-1
 match ipv4 source address
 collect counter packets
!
flow exporter FLOW-EXPORTER-1
 destination 10.0.1.2
 output-features
 dscp 18
!
flow monitor FLOW-MONITOR-1
 record FLOW-RECORD-1
 exporter FLOW-EXPORTER-1
 cache entries 1024
!
ip cef
!
class-map match-any COS3
!
policy-map PH_LABS_FRL_64k_16k_16k_8k_8k
 class COS3
  bandwidth percent 2
  random-detect dscp-based
  random-detect exponential-weighting-constant 1
  random-detect dscp 18 200 300 10
!
interface Ethernet 0/0
 ip address 10.0.0.1 255.255.255.0
 ip flow monitor FLOW-MONITOR-1 input
!
interface Ethernet 0/1
 ip address 10.0.1.1 255.255.255.0
 service-policy output PH_LABS_FRL_64k_16k_16k_8k_8k
!

The following display output shows that the flow monitor is exporting data using output feature support that enables the exported data to use QoS:

Router# show flow monitor FLOW-MONITOR-1
Flow Exporter FLOW-EXPORTER-1:
  Description:              User defined
  Tranport Configuration:
    Destination IP address: 10.0.1.2
    Source IP address:      10.0.0.1
    Transport Protocol:     UDP
    Destination Port:       9995
    Source Port:            56750
    DSCP:                   0x12
    TTL:                    255
    Output Features:        Used

Example Configuring Version 5 Export

The following example shows how to configure version 5 export for Flexible NetFlow.

This sample starts in global configuration mode:

!
flow exporter EXPORTER-1
 destination 172.16.10.2
 export-protocol netflow-v5
 transport udp 90
 exit
!
flow monitor FLOW-MONITOR-1
 record netflow ipv4 original-input
 exporter EXPORTER-1
!
ip cef
!
interface Ethernet 0/0
 ip address 172.16.6.2 255.255.255.0
 ip flow monitor FLOW-MONITOR-1 input
!

Where to Go Next

For information on advanced Flexible NetFlow configurations for specific purposes such as QoS and bandwidth monitoring, application and user flow monitoring and profiling, and security analysis, refer to the "Customizing Cisco IOS Flexible NetFlow Flow Records and Flow Monitors" module.

If you want to configure flow sampling to reduce the CPU overhead of analyzing traffic, refer to the "Using Cisco IOS Flexible NetFlow Flow Sampling to Reduce the CPU Overhead of Analyzing Traffic" module.

If you want to configure any of the predefined records for Flexible NetFlow, refer to the "Configuring Cisco IOS Flexible NetFlow with Predefined Records" module.

Additional References

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

Overview of Flexible NetFlow

"Cisco IOS Flexible NetFlow Overview"

Emulating original NetFlow with Flexible NetFlow

"Getting Started with Configuring Cisco IOS Flexible NetFlow"

Customizing Flexible NetFlow

"Customizing Cisco IOS Flexible NetFlow Flow Records and Flow Monitors"

Configuring flow sampling to reduce the overhead of monitoring traffic with Flexible NetFlow

"Using Cisco IOS Flexible NetFlow Flow Sampling to Reduce the CPU Overhead of Analyzing Traffic"

Configuring Flexible NetFlow using predefined records

"Configuring Cisco IOS Flexible NetFlow with Predefined Records"

Using Flexible NetFlow Top N Talkers to analyze network traffic

"Using Cisco IOS Flexible NetFlow Top N Talkers to Analyze Network Traffic"

Configuring IPv4 multicast statistics support for Flexible NetFlow

"Configuring IPv4 Multicast Statistics Support for Cisco IOS Flexible NetFlow"

Configuration commands for Flexible NetFlow

Cisco IOS Flexible NetFlow Command Reference

Standards

Standard

Title

None

--

MIBs

MIB

MIBs Link

None

To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs

RFCs

RFC

Title

RFC 3954

Cisco Systems NetFlow Services Export Version 9

Technical Assistance

Description

Link

The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

http://www.cisco.com/cisco/web/support/index.html

Feature Information for Flexible NetFlow

The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.

Table 1 Feature Information for Flexible NetFlow

Feature Name

Releases

Feature Information

Flexible NetFlow

12.2(33)SRC

12.2(50)SY

12.4(9)T

15.0(1)SY

Flexible NetFlow is introduced.

Support for this feature was added for Cisco 7200 series routers in Cisco IOS Release 12.2(33)SRC.

The following commands were introduced or modified: cache (Flexible NetFlow), clear flow exporter, clear flow monitor, clear sampler, collect counter, collect flow, collect interface, collect ipv4, collect ipv4 destination, collect ipv4 fragmentation, collect ipv4 section, collect ipv4 source, collect ipv4 total-length, collect ipv4 ttl, collect routing, collect timestamp sys-uptime, collect transport, collect transport icmp ipv4, collect transport tcp, collect transport udp, debug flow exporter, debug flow monitor, debug flow record, debug sampler, description (Flexible NetFlow), destination, dscp (Flexible NetFlow), exporter, flow exporter, flow monitor, flow platform, flow record, ip flow monitor, match flow, match interface (Flexible NetFlow), match ipv4, match ipv4 destination, match ipv4 fragmentation, match ipv4 section, match ipv4 source, match ipv4 total-length, match ipv4 ttl, match routing, match transport, match transport icmp ipv4, match transport tcp, match transport udp, mode (Flexible NetFlow), option (Flexible NetFlow), record, sampler, show flow exporter, show flow interface, show flow monitor, show flow record, show sampler, source (Flexible NetFlow), statistics packet, template data timeout, transport (Flexible NetFlow).

Flexible NetFlow--IPv4 Unicast Flows

12.2(33)SRC

12.2(50)SY

12.4(9)T

15.0(1)SY

Enables Flexible NetFlow to monitor IPv4 traffic.

Support for this feature was added for Cisco 7200 series routers in Cisco IOS Release 12.2(33)SRC.

The following commands were introduced or modified: collect routing, debug flow record, collect ipv4, collect ipv4 destination, collect ipv4 fragmentation, collect ipv4 section, collect ipv4 source, ip flow monitor, match ipv4, match ipv4 destination, match ipv4 fragmentation, match ipv4 section, match ipv4 source, match routing, record, show flow monitor, show flow record.

Flexible NetFlow--NetFlow v9 Export Format

12.2(33)SRE

12.2(50)SY

12.4(9)T

15.0(1)SY

Enables sending export packets using the Version 9 export format.

Support for this feature was added for Cisco 7200 and 7300 Network Processing Engine (NPE) series routers in Cisco IOS Release 12.2(33)SRE.

No commands were introduced or modified by this feature.

Flexible NetFlow--IPv6 Unicast Flows

12.2(33)SRE

12.2(50)SY

12.4(20)T

15.0(1)SY

Enables Flexible NetFlow to monitor IPv6 traffic.

Support for this feature was added for Cisco 7200 and 7300 Network Processing Engine (NPE) series routers in Cisco IOS Release 12.2(33)SRE.

The following commands were introduced or modified: collect routing, debug flow record, match routing, record, show flow monitor, show flow record, collect ipv6, collect ipv6 destination, collect ipv6 extension map, collect ipv6 fragmentation, collect ipv6 hop-limit, collect ipv6 length, collect ipv6 section, collect ipv6 source, collect transport icmp ipv6, ipv6 flow monitor, match ipv6, match ipv6 destination, match ipv6 extension map, match ipv6 fragmentation, match ipv6 hop-limit, match ipv6 length, match ipv6 section, match ipv6 source, match transport icmp ipv6.

Flexible NetFlow--Output Features on Data Export

12.4(20)T

Enables sending export packets using QoS and encryption.

The following command was introduced: output-features.

Flexible NetFlow--NetFlow V5 Export Protocol

12.2(33)SRE

12.2(50)SY

12.4(22)T

15.0(1)SY

Enables sending export packets using the Version 5 export protocol.

Support for this feature was added for Cisco 7200 and 7300 Network Processing Engine (NPE) series routers in Cisco IOS Release 12.2(33)SRE.

The following command was introduced: export-protocol.

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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.

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