Description of problem: UDP Packet duplication occurs when sendto() called within many process at the same time. each processes are joined to different multicast addr,port. ratio of duplication is around 0.6%-2.0% of all sent packet per 1 addr. (verified by tcpdump) Version-Release number of selected component (if applicable): uname -a Linux xxxxxxx 2.6.9-5.EL #1 Wed Jan 5 19:21:57 EST 2005 x86_64 x86_64 x86_64 GNU/Linux How reproducible: As the number of the processes increases, the packet repetition rate rises. Steps to Reproduce: 1.send multicast packet with sendto(). 2.capture any multicast group with tcpdump 3. Actual results: when 20 process startup, each process sent 10000 udp packet. captured 1 multicast addr with tcpdump, and received 10003packet. 3 packets was the same one sent just before. Expected results: Additional info: it never happen if sendto() called sequential.
I'm going to set up a system to reproduce this. In the interim, if you have a copy of the tcpdump that you captured for me to review, that would be helpful. Thanks!
ping, any word on that tcpdump?
closing, no response