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I have three machines on my VLAN- A, B and C, all running Ubuntu. If I run Wireshark in promiscuous mode on, say, machine B, I am unable to see the traffic between machine A/C and the internet. The LAN traffic between them is detected fine. Where am I going wrong?

asked 28 Aug '12, 02:23

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pnp
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You're capturing at a switch, and a switch will not push all packets to all ports like a hub used to do. That means that the conversation between A and C is bypassing your link to B, which is why it can't see the traffic.

Please take a look at http://wiki.wireshark.org/CaptureSetup/Ethernet

permanent link

answered 28 Aug '12, 02:28

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Jasper ♦♦
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question asked: 28 Aug '12, 02:23

question was seen: 4,096 times

last updated: 28 Aug '12, 02:28

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