root@monitor:~#   rrdtool create target.rrd \
         --start 1394405025 \
         --step 5 \
         DS:speedIn:COUNTER:10:U:U \
         DS:speedOut:COUNTER:10:U:U \
         RRA:AVERAGE:0.5:2:60 \
         RRA:AVERAGE:0.5:60:12