Hi Aaron, Thanks for a brief explanation. Our aplication/software actually does not listen in any interface. Application/Software runs in centos pc as already mentioned.
Our application/software takes the packets from the tcp/ip stack (after the packets reached the tcp/ip stack of cent-os) and then do some processing. Due to the confidentiality of this app/software, I am really sorry that I cannot go beyond this limit, but this is how our app/soft works. I suspect packets replayed through tcpreplay didn't reach the tcp/ip stack. Am I doing anything wrong in the modification of pcap ??? Regards, S. Senthil kumar -----Original Message----- From: Aaron Turner [mailto:synfina...@gmail.com] Sent: Friday, April 06, 2012 10:37 AM To: Main forum for tcpreplay Subject: Re: [Tcpreplay-users] tcpreplay Client Server communication On Thu, Apr 5, 2012 at 9:49 PM, Senthil Kumar S <senthilkuma...@sasken.com> wrote: > Hi Aaron, > > Thanks for the reply. > > The DUT is a CentOS PC, in which the application developed by us will run. > The packets (from pcap file) are pumped with the set up I mentioned in the > mail chain(please take a look). Sorry, but CentOS PC isn't actually helpful any more then saying "it's a system with a CPU and two network ports". What kind of "network device" is it? Does it forward packets like a router or bridge? Basically, what is it supposed to do with the packets tcpreplay sends? How does it "listen" for traffic? For example, a router "sees" traffic sent to its MAC address, but a bridge is completely transparent (it sees everything). Conversely, webserver only sees traffic which is sent to both it's MAC and IP address. > > The aplication/software I am running on the DUT does not see the packets. > This is the issue. Any more explanation needed I can give. I understand. But what is this application/software? What does it do? How does it "see" traffic? For example, Wireshark and tcpdump "sniff" on the network port and see all traffic that is delivered to that port. You can tell them to not run in "promiscuous mode" and so they'll only see traffic destined to the MAC address of the host they're running on, but they still will ignore the destination IP address. But a webserver runs on top of the host TCP/IP stack and will only see traffic which has the correct L2 and L3 addresses *AND* only after a completed 3 way TCP handshake (which as I already explained tcpreplay can't do). -- Aaron Turner http://synfin.net/ Twitter: @synfinatic http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & Windows Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. -- Benjamin Franklin "carpe diem quam minimum credula postero" ------------------------------------------------------------------------------ For Developers, A Lot Can Happen In A Second. Boundary is the first to Know...and Tell You. Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! http://p.sf.net/sfu/Boundary-d2dvs2 _______________________________________________ Tcpreplay-users mailing list Tcpreplay-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tcpreplay-users Support Information: http://tcpreplay.synfin.net/trac/wiki/Support SASKEN BUSINESS DISCLAIMER: This message may contain confidential, proprietary or legally privileged information. In case you are not the original intended Recipient of the message, you must not, directly or indirectly, use, disclose, distribute, print, or copy any part of this message and you are requested to delete it and inform the sender. Any views expressed in this message are those of the individual sender unless otherwise stated. Nothing contained in this message shall be construed as an offer or acceptance of any offer by Sasken Communication Technologies Limited ("Sasken") unless sent with that express intent and with due authority of Sasken. Sasken has taken enough precautions to prevent the spread of viruses. However the company accepts no liability for any damage caused by any virus transmitted by this email. Read Disclaimer at http://www.sasken.com/extras/mail_disclaimer.html ------------------------------------------------------------------------------ For Developers, A Lot Can Happen In A Second. Boundary is the first to Know...and Tell You. Monitor Your Applications in Ultra-Fine Resolution. Try it FREE! http://p.sf.net/sfu/Boundary-d2dvs2 _______________________________________________ Tcpreplay-users mailing list Tcpreplay-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/tcpreplay-users Support Information: http://tcpreplay.synfin.net/trac/wiki/Support
