Yes, Cisco ASR does support NetFlow export and you can enable it on 10G interfaces too. No limitations with that. Blog below on the NetFlow configuration for Cisco ASR:
https://blogs.manageengine.com/netflowanalyzer/2011/06/30/netflow-configuration-for-cisco-xr-12000-series-routers
As for the performance impact, it entirely depends on the traffic volume. Higher the volume of traffic passing through the interfaces, more flows are generated and thus higher the CPU utilization. I have read somewhere that for around 10,000 flows per second, the CPU utilization increase can be around 10%.
Regards,
Don Thomas Jacob
ManageEngine NetFlow Analyzer
Regards,
Don Thomas Jacob
http://www.solarwinds.com/netflow-traffic-analyzer.aspx
Head Geek @ SolarWinds
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