Flexible NetFlow through Cryptomap Tunnel

linker.team · ‎09-03-2010

Hi Guys,

Came to know that FNF will solve the issue of exporting NetFlow packets through Cryptomap Tunnel.

http://www.cisco.com/en/US/prod/collateral/iosswrel/ps6537/ps6555/ps6601/ps6965/prod_white_paper0900aecd804be1cc.html

Confiugred my router to export Flexible NetFlow through Cryptomap tunnel. But I am not seeing any NetFlow packets on my management server. Verified this using packet capture tool (Wireshark). I have attached my configuration. Any help will be deeply appreciated.

jakewilson · ‎09-06-2010

Hello,

If the traffic is encrypted in a tunnel, some NetFlow Analyzers like Scrutinizer will drop data such as:

ENCAP(98)
ESP(50)
ETHERIP(97)
GRE(47)
IPIP(94)

This done because some routers will export the same data twice (i.e. once in native format, a second time as tunneled traffic). This causes excessive utilization reports that are not accurate.

This dropping of traffic was recommened by Cisco. I hope I understood your question.

Jake

linker.team · ‎09-08-2010

Hi,

I think you have not understood my question. I have mentioned that NetFlow packets are not reaching the server, thats why I have mentioned that wireshark also does not packets on the server.

jakewilson · ‎09-08-2010

sorry about that. Any chance something in the path could be filtering the traffic? I haven't set up a Cryptomap Tunnel before.