I have a server that's not acting normally. We see the
application data packets arriving, but it seems that the
app is ignoring some of them. We're curious if there's a
problem with either the NIC or the switch port. So... is
there a way I can run a data (both udp and tcp) stress
test to verify if there's any data corruption happening?

I want to run a long, heavy load test and get some kind
of simple output of % of missing or corrupt packets, etc.
Does something already exist that could handle this task?