udp packet not reach application
I have following issue ( kernel 3.2.28):
a device sending udp traffic to UDP Port x -> my udp app ( listen on port x)
at first, it was working. my app did get udp traffic.
after a while, strace showed that my app stuck at recvfrom, no udp traffic
but tcpdump showed the udp traffic still coming.
Even if I restart my app, strace showed that no udp traffic at my app.
it seems the kernel did not deliver the udp packet to my app.
I have to restart NIC interface, then I could see udp traffic received at my app.
What could be wrong?