Wireshark-users: Re: [Wireshark-users] Traffic bewteen two IP addresses

From: Sake Blok <sake@xxxxxxxxxx>
Date: Fri, 29 Aug 2008 00:18:43 +0200
On Thu, Aug 28, 2008 at 03:21:55PM -0600, Bryan Carter wrote:
>    This one is just getting away from me and I can't get my head around it,
>    and I cannot find an example anywhere.
> 
>     
> 
>    I have WireShark running on a SPAN port that is watching several ports on
>    a Cisco switch. I simply want a capture filter that will allow me to see
>    ALL of the traffic between two SPECIFIC ip addresses.  So I ONLY want to
>    see traffic from IP1, IF it is going to, or coming from IP2.  What would
>    that CAPTURE filter look like?

how'bout:

"host <IP1> and host <IP2>"

this would require the presence of IP1 in either src-ip or dst-ip AND
the presence of IP2 in either src-ip or dst-ip.

It all changes when vlan-tags are present. If all frames are tagged,
then "vlan and (host <IP1> and host <IP2>)" will do the trick. But
if some frames are not tagged and some are tagged, then it will get
complicated, if not impossible...

Cheers,
    Sake