Neflow ON all the time recommended?

[fjcardenas-1]

I have a simple question that might be easy to answer but if you have a supporting document please provide the link. The question is:

Is it recommended to have Netflow running permanently in a 6509 or is it a tool that needs to be enable only as needed (reactive troubleshooting)?

Planing on enabling it on our ISP port for traffic analysis using solarwinds, but unsure if it is a feature that should stay ON all the time since i think it may cause performance issues or increase CPU utilization in the switch. I may be wrong so any supportive information is welcome.

Thank you,

Francisco.

[InayathUlla Sharieff]

Francisco,

Its all depends upto the Customer. I have seen customer enabling it on always on there device as they want to see the traffic of that muxes which they would like to monitor on.

We should not run into any performance issue while enabling netflow feature on those 1/2
interfaces. There can be slight impact on CPU depending on if netflow export is enabled
and number of exported flows is high. Below document should explain ways to reduce the
number of exported flows by not taking any hit on CPU:

http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/70974-net
flow-catalyst6500.html#opconf

HTH