rrdtool graph /your/file/name/here.gif \
     --start '-2d' \
     --vertical-label 'bit/sec' \
     --width '640' \
     --title 'localhost MySQL traffic +out/-in' \
     'DEF:A=MySQL_dst.rrd:in_bytes:AVERAGE' \
     'DEF:B=MySQL_dst.rrd:out_bytes:AVERAGE' \
     'DEF:C=MySQL_src.rrd:in_bytes:AVERAGE' \
     'DEF:D=MySQL_src.rrd:out_bytes:AVERAGE' \
     'CDEF:E=A,C,+,8,*,-1,*' \
     'CDEF:F=B,D,+,8,*' \
     'COMMENT:A) MySQL_dst AVERAGE in_bytes' \
     'COMMENT:\n' \
     'COMMENT:B) MySQL_dst AVERAGE out_bytes' \
     'COMMENT:\n' \
     'COMMENT:C) MySQL_src AVERAGE in_bytes' \
     'COMMENT:\n' \
     'COMMENT:D) MySQL_src AVERAGE out_bytes' \
     'COMMENT:\n' \
     'AREA:E#0000FF:A,C,+,8,*,-1,*' \
     'GPRINT:E:MIN:(min=%.0lf' \
     'GPRINT:E:AVERAGE:ave=%.0lf' \
     'GPRINT:E:MAX:max=%.0lf)' \
     'COMMENT:\n' \
     'AREA:F#0000FF:B,D,+,8,*' \
     'GPRINT:F:MIN:(min=%.0lf' \
     'GPRINT:F:AVERAGE:ave=%.0lf' \
     'GPRINT:F:MAX:max=%.0lf)' \
     'COMMENT:\n'