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Port mirroring vs Packet sniffer




simple question for you. I want to use the Packet sniffer sensor with port mirroring to get stats on what is running on our network.

I have 2 vlan to monitor. Is it ok to create a port mirroring from these 2 vlan on the same network card in PRTG or should I seperate it on 2 NIC ?

My concern is.....if both vlan are "port mirrored" on the same destination port and there is traffic between these two vlan, will my traffic stats be doubled and innacurate ?

thank you

packet-sniffer port-mirroring span

Created on Nov 16, 2010 8:00:02 PM

1 Reply




to be honest, we're not exactly sure. Port Mirroring might be slightly different with each vendor. Therefore, 2 NICs are a possibility (and then two Packet Sniffer Sensors in PRTG), or maybe one NIC and also two Packet Sniffer Sensors in PRTG, but this time each one with a filter. We would recommend to run some tests (copy a certain amount of data and then compare the values).

Best Regards.

Created on Nov 17, 2010 5:01:01 PM by  Torsten Lindner [Paessler Support]

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