[Tcpreplay-users] tcpreplay + multicast on different kernels

[Љубомир С. <lj...@gm...>]

Hi all,

I have a problem that might not be related to tcpreplay, but posting here
hoping that someone has similar experience.

Application I work on reads multicast udp data. Tcpreplay is used as a part
of testing environment: after live udp multicast is recorded it's played
back later. For testing purposes it was also written custom dummy network
driver that implements loopback's .ndo_start_xmit routine. So, live data is
captured somewhere else, then played back on custom loopback interface.
Here is description of environments:

Environment A:
OS: GNU/Linux Centos 5.7
Kernel: 2.6.18-274.17.1.el5.centos.plus (64bit)
tcpreplay version: 3.4.3 (build 2375)
Copyright 2001-2009 by Aaron Turner <aturner at synfin dot net>
Cache file supported: 04
Compiled against libdnet: 1.11
Compiled against libpcap: 0.9.4
64 bit packet counters: enabled
Verbose printing via tcpdump: enabled
Packet editing: disabled
Fragroute engine: enabled
Injection method: PF_PACKET send()

Environment B:
OS: GNU/Linux Centos 6.2
Kernel: 2.6.32-220.4.2.el6.x86_64
tcpreplay version: 3.4.4 (build 2450)
Copyright 2000-2010 by Aaron Turner <aturner at synfin dot net>
Cache file supported: 04
Compiled against libdnet: 1.11
Compiled against libpcap: 1.0.0
64 bit packet counters: enabled
Verbose printing via tcpdump: enabled
Packet editing: disabled
Fragroute engine: enabled
Injection method: PF_PACKET send()

For testing purposes several items were used:
EC: epoll based udp client - basically normal udp client
TS: tcpreplay based multicast data server (sudo tcpreplay -i custom0 -L 1
-p 1000 multicast_data.pcap)
SS: socat based multicast server (echo test | sudo socat -u STDIO
UDP-DATAGRAM:239.192.111.9:9019,sourceport=43283,bindtodevice=custom0)

The goal is to have TS -> EC working. But the problem is that it doesn't
work on environment B !!

Here are results of aditional tests:

environment A:
SS -> EC (all packets are captured twice each)
TS -> EC - multicast data (all packets are captured once each)
TS -> EC - replaying previously recored SS->EC test (nothing captured)

environment B:
SS -> EC (all packets are captured once each)
TS -> EC - multicast data (!!! NOTHING !!!)
TS -> EC - replaying previously recored SS->EC test (nothing captured)

Does anyone have an idea?

Best regards and thank you,
Ljubomir