SMTP no-such-user issues

Nathan Ward nanog at
Tue Jun 17 13:21:40 UTC 2008

On 18/06/2008, at 1:20 AM, Steve Bertrand wrote:

> Steve Bertrand wrote:
>> Frank Bulk - iNAME wrote:
>>> Once you've performed a full capture on port 25, Wireshark does a  
>>> nice job
>>> of providing an option to extract the relevant conversation by
>>> right-clicking on just one packet in that conversation and choosing
>>> something called "Follow the TCP stream", I believe.
>> Ok. I've never captured in tcpdump and then imported into Wireshark  
>> before, but I'll do some tests, scp the file to my Windows  
>> workstation, then follow the stream.
>> Once I ensure I get a clean stream, I'll post the results.
> As I research the documentation on the how-to specifics on capturing  
> with tcpdump in a format that is Wireshark compatible, is there  
> anyone here that could perform a simple test against their own  
> domain email system, that can confirm or deny what I have been  
> witnessing?

Wireshark reads pcap files. Spit them out with this option on the  
tcpdump commandline.

-w file

Nathan Ward

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