Wireshark · Wireshark-users: Re: [Wireshark-users] capture traffic to PLC

["David H. Lipman" <DLipman@xxxxxxxxxxx>]

From: "Marius-Simion Cristea" 
<cristea12@xxxxxxxxx>

> Hi,
>
> I want to capture the traffic (the commands) that are sent from a SCALANCE 
> touch panel
> emulator to a PLC. The configuration of my network looks like this:
>
> Emulator---HUB---Scalance_Switch---PLC
>   |
> PC (Wireshark)
>
> I'm giving commands to the PLC from the emulator, the PLC responds, but I 
> can't capture
> any of those commands using Wireshark, i'm seeing only ARP, LLDP, PN-DCP 
> packets and some
> other broadcast packets.
>
> Is it possible to capture those commands using Wireshark? if so, what am I 
> doing wrong?
> because, as far as I know the hub must send all the packets that are meant 
> for the PLC
> also to the PC.
>
> Thanks!

Maybe I am off but...

Instead of

Emulator---HUB---Scalance_Switch---PLC
 |
PC (Wireshark)

Go this route...
Drop an Ethernet hub between the Scalance_Switch and the PLC and sniff from 
that POV.
{ Of course making sure the PC w/Wireshark has a promiscuous NIC }

Emulator---HUB---Scalance_Switch---HUB---PLC
                                                          |
                                             PC (Wireshark)


--
Dave
Multi-AV Scanning Tool - http://multi-av.thespykiller.co.uk
http://www.pctipp.ch/downloads/dl/35905.asp