rrdtool create eth0.rrd            \
        --step 300                 \
        DS:rx:COUNTER:600:U:U      \
        DS:tx:COUNTER:600:U:U      \
        RRA:AVERAGE:0.5:1:2016

rrdtool create eth1.rrd            \
        --step 300                 \
        DS:rx:COUNTER:600:U:U      \
        DS:tx:COUNTER:600:U:U      \
        RRA:AVERAGE:0.5:1:2016
rrdtool create eth2.rrd            \
        --step 300                 \
        DS:rx:COUNTER:600:U:U      \
        DS:tx:COUNTER:600:U:U      \
        RRA:AVERAGE:0.5:1:2016