Aaron Turner wrote: > On Tue, Dec 30, 2008 at 5:13 AM, Abdelrazak Younes <[email protected]> wrote: > >> ValentÃn Carela wrote: >> >>> Hi Abdel, >>> >>> I think I'm using tcpreplay in a similar scenario. I have a computer >>> with two ethernet cards connected. >>> >>> First I change the MAC addresses of the trace with tcprewrite >>> >>> tcprewrite --dmac=XX:XX:XX:XX:XX:XX (eth2 @MAC) --smac=XX:XX:XX:XX:XX:XX >>> (eth1 @MAC) -i trace.pcap -o new_trace.pcap >>> >>> Then I use tcpreplay to send the packets from eth1 to eth2 >>> >>> tcpreplay -i eth1 new_trace.pcap >>> >>> I don't know if it is exactly the same scenario but I hope it helps. >>> >> Yes, that's exactly what I am after. But are you sure that the stream >> will effectively go out of eth1 into eth0? My fear is that the system >> (linux) will shortcut the path... >> >> FYI I want to monitor the performance between two PLC devices that are >> connected to eth0 and eth1. >> >> Thanks Valentin, >> Abdel. >> > > You don't need to worry about Linux "short cutting" the packets- > tcpreplay insures the packets actually goes out the interface(s) you > tell it to. To make sure the listening side of the connection > actually reads the packets rather then silently dropping them, you > need to make sure that: > > 1) the destination MAC/IP address matches the listening interface > 2) the source IP/MAC does NOT match any real interfaces on the system > > #2 is important because Linux treats packets received on a > non-loopback interface with a source MAC/IP of another interface as a > "bogon" or forged packet and drops it for security reasons.
OK, got it, thanks. > If > you're willing to recompile your kernel, it's pretty simple to turn > off this bogon check. > I'll try that, which setting is that? > Hope that helps, > Yes, very much, thank you. Abdel. ------------------------------------------------------------------------------ _______________________________________________ Tcpreplay-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tcpreplay-users Support Information: http://tcpreplay.synfin.net/trac/wiki/Support
