[CentOS] What about port mirroring? (Was: Switch to measure traffic at IP level)

Hello everyone:

I was just reading an ntop guide and it mentioned
many switches have port mirroring.

According to what I am reading, the Cisco I am using
will copy all traffic to the mirror port.  Then,
I can monitor what is going on from there.

That seems like a good way to do this.

Are there any pitfalls with this approach?

Would ntop be a good tool for it?

I would like to graph total bytes in and out
as well as 95% usage on an IP address level.
I would like daily, weekly, and monthly graphs.

Thanks,
	Neil

--
Neil Aggarwal, (281)846-8957, www.JAMMConsulting.com
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