Netflow on Nexus 7000

[Pablo.Ayala]

Hello team, hope that you’re doing great.

I configured NTA 3.5 and Network Performance Monitor V9.5. Everything looks great but the problem that I have is that I configured my Nexus 7000 with version 9 and the console (NTA) is receiving the next output: Netflow Receiver Service [NETFLOW] encountered an invalid V9 template with ID 256 from device 10.63.33.254

Can anyone please help me :S

Thanks in advanced.

[mcbridea]

Hi Pablo,

That is the default template ID so it should be OK. Do you see flows from that device and get the error in the event log or do you only get the error and no data.

Andy

[Pablo.Ayala]

Andy thanks for your quick response.

The problem that I have is that in the main window of the NTA I never get the flows. There is some part of this window that says: Netflow Sources and over there I have the VDC of the Nexus and under the LAST NETFLOW RECEIVED label says NEVER so I'm not receiving anything. The configure of the Nexus is:

configure terminal
 feature netflow
!
 flow record ElektraIPv4Flow
 description IPv4Flow
 match ip protocol
 collect counter bytes
 collect counter packets
 exit
!
flow exporter ElektraExportV9
 description Exportv9
 destination 10.63.33.56
 source vlan 630
 version 9
 transport udp 9995
 exit
!
flow monitor ElektraMonitorV9
 description IPv4Monitor
 exporter ElektraExportV9
 record ElektraIPv4Flow
 exit
!
interface vlan 630
 ip flow monitor ElektraMonitorV9 input
 ip flow monitor ElektraMonitorV9 output

If I show the Nexus outputs we will see flows to the Collector.

Thanks again

[billsardine · Accepted solution]

The correct config for a 7k is as follows

flow exporter FLOW_NAME
  destination 10.32.7.254 use-vrf management
  transport udp 2055
  source mgmt0
  version 9
    template data timeout 90
flow monitor FLOW_NAME 
  record netflow-original
  exporter FLOW_NAME

if you use the record netflow-original command you dont have to create a flow record

[bsoth]

I know this post is from February, but wondering about contexts and vlans in the 7k. we have several.

If I configure

flow exporter FLOW_NAME
  destination 10.32.7.254 use-vrf management
  transport udp 2055
  source mgmt0
  version 9
    template data timeout 90
flow monitor FLOW_NAME 
  record netflow-original
  exporter FLOW_NAME

 If I dont create a flow record, will this basically capture everything or is this per context?

Im new to the 7k and Netflow so maybe Im asking an obvious question...

[jason.miller1]

This is a per VDC configuration.  Meaning that you have to configure this on every VDC.

[mcbridea]

I see. That template  is a flexible NetFlow implementation and won't work unless you also match

ip source, ip destination, tos, input interface, destination port, source port.

The default template for v9 includes these but I'm not sure how that is implemented for the 7K. For other platforms you just don't specify a template or any match/collect parameters.