Huge thanks to our Platinum Members Endace and LiveAction,
and our Silver Member Veeam, for supporting the Wireshark Foundation and project.

Wireshark-users: Re: [Wireshark-users] capture filters

From: Guy Harris <guy@xxxxxxxxxxxx>
Date: Mon, 31 Dec 2007 15:28:23 -0800
Witton, David wrote:

In an unfiltered capture, I am seeing quite a bit of TCP traffic
(>90%), most of it involving machines other than the one I'm running
Wireshark on.

Most, or all? I.e., in an unfiltered capture, are you seeing TCP traffic to and from the machine running Wireshark?

That doesn't seem to match the case described in the FAQ
below - or am I wrong?

That sounds like a different case.

What OS are you running on the machine doing the capture? And what type of network adapter are you capturing on?

And, if this is on Ethernet, are you using VLANs? If so, is the TCP traffic to and from the host running Wireshark on a VLAN? (I.e., does it have a VLAN header?)