Discover unkown client on network consuming 50% bandwidth on 3rd shift

[zzbronski]

I am seeing a bandwidth spike at around 2:40am every morning that lasts for about 10 mintues but I can't remember how to find what the device is that is causing it. I have a Fluke Optiview II network analyzer connected to the network but it only shows me the top hosts on the current vlan. It has been a few years since I did this and just need a refresher on how to configure the port on the switch so it sees all traffic from all vlans and switches so I can identify the culprit. I am pretty sure it was a debug command.

[Todd Pula]

On most Cisco switches, you can enable a feature called SPAN which will allow you to replicate port or VLAN traffic to a destination port.  Please refer to the doc below for some configuration samples.

http://www.cisco.com/en/US/customer/products/hw/switches/ps708/products_tech_note09186a008015c612.shtml

[Panos Kampanakis]

You course also leverage Netflow to get information about connections and thus find top talkers and where the bw is spent.

I hope it helps.

PK