Wireshark-users: Re: [Wireshark-users] Capturing network traffic using wireshark remotely

From: "Michael Glenn" <MGlenn@xxxxxxxxxxxxxxx>
Date: Thu, 28 Jan 2010 16:22:47 -0500
"But, question is can I get the capture without doing port mirroring?"
 
Nope; connections on a switch are strictly point-to-point for anything except broadcast packets: Any traffic between 1 & 2 won't even show up on the line to 3.
 
Only thing I can suggest is that you find a dumb hub (*not* a switch!) and connect it somewhere along the line between 1 & 2, then connect machine #3 to the hub.


>>> sean bzd <seanbzd@xxxxxxxxx> 01/28/2010 15:21 >>>
Folks,
Need some advice/help here.

We have a scenario:

3 Windows machines all connected to the same Cisco Switch.
Machine1 and Machine2 are exchanging some data that need to be captured. Ideally, I could install wireshark on either Machine1 or Machine2 and capture all the traffic being exchanged between the two. But since these are production machines, we don't want to change/install anything on these 2 machines. Is there a way I can install wireshark on Machine3 and capture the traffic between Machine1 and Machine2? I know I can do port mirroring on the Cisco switch and capture it from Machine3. But, question is can I get the capture without doing port mirroring? I see that the capture Options dialog box in wireshark has an option for Local Vs. Remote interface? What is it used for? Has anyone used this before?

Thanks for your help.
Sean.