Cisco 4331 flow export from vrf

[Kevin.Beierstettel]

Dear all,

I have a problem regarding netflow export from a Cisco 4331. I want to export netflow traffic to a specific destination. The problem is that the source should be the loopback interface on the router which is in a specific VRF:

Example:

flow exporter TEST
destination x.x.x.x
source Loopback1
transport udp 2055
template data timeout 1

flow monitor My-Flow-Test
exporter TEST
record netflow-original

interface Loopback1
ip vrf forwarding TEST_VRF
ip address Y.Y.Y.Y 255.255.255.255
end

It´s working when I´m using a Loopback Interface which is not in an VRF but when I use the "vrf forwarding" the source Interface IP is wrong:

sh flow exporter TEST
Flow Exporter TEST:
Description: User defined
Export protocol: NetFlow Version 9
Transport Configuration:
Destination IP address: X.X.X.X
Source IP address: "Not Y.Y.Y.Y"
Source Interface: Loopback1
Transport Protocol: UDP
Destination Port: 2055
Source Port: 53015
DSCP: 0x0
TTL: 255
Output Features: Used

Does anyone have an Idea how to resolve this problem? I need to export through this Loopback Interface over that VRF.

Best regards,

Kevin 

[Julio E. Moisa]

Hi

If you are using VRF probably there is no communication between your loopback and the Netflow collector server because the loopback is under a VRF and the Netflow collector is over the global routing table, so you could verify it to enable routing between them, you could use static routes depending of your topology.

[Kevin.Beierstettel]

Thanks for your reply. The routing between the loopback(In the TEST_VRF) and the destination server is working fine. I guess it´s a configuration issue because if we use the normal ip-flow commands we have the same issue on other Cisco routers.

We have to configure the VRF explicit to make it work:

#ip flow-export destination x.x.x.x 2055 vrf TEST_VRF

Otherwise if we use "#ip flow-export destination x.x.x.x 2055" in the "sh ip flow export" the given Loopback IP-Address is not right:

#sh ip flow export
Flow export v9 is enabled for main cache
Export source and destination details :
VRF ID : Default
Source(1) "Not the LoopbackIP" (Loopback1)
Destination(2) x.x.x.x (2055)
Version 9 flow records

But this configuration will not work on Cisco 4331.

[perkin]

Hello 

I have the same question and after I googled it seems that is work as (cisco) design

you can refer to this discussion 

https://community.cisco.com/t5/switching/netflow-vrf-export/td-p/1339418

even I tried on 16.9 code and that still the same..

so that is support on VRF but it (seems) it is not supported on the "real" mgmt interface / mgmt-intf

hope this help form a year later.