"$ iperf --output somefile.log -c servername" does not write the report to the specified output file. The report is still shown on stdout as it does with the default options. Using the "-o somefile.log" does not work either.
"$ sudo iperf -s -D -o /var/log/iperf.log" starts the daemon, but the logfile is never written to or created.
"$ iperf -v" iperf version 2.0.4 (7 Apr 2008) pthreads
"$ uname -a" Linux servername 2.6.32-22-generic #33-Ubuntu SMP Wed Apr 28 13:27:30 UTC 2010 i686 GNU/Linux