# [rrd-users] Newbie help with rrdtool

Simone Caruso info at simonecaruso.com
Sun Sep 18 15:15:39 CEST 2011

```>> For testing I tried something like this:
>>
>> # rrdtool create test.rrd  --start 920808200  DS:bytes:ABSOLUTE:300:U:U
>> RRA:AVERAGE:0.5:1:500
>
> 920808200  cannot be divided by 300 (without remainder) so maybe it is not
> what you expect. Or maybe it is just a typo?
Ok, i used a 300 multiple as startdate, now i solved an error in graph.

Thank to you i got a good graph with Kbytes/s using this:

# rrdtool create test.rrd --start 920804400 DS:bytes:ABSOLUTE:600:U:U
RRA:AVERAGE:0.5:1:3600

# rrdtool update test.rrd 920804700:10 920805000:20 920805300:15
# rrdtool update test.rrd 920805600:10 920805900:40 920806200:20

# rrdtool graph speed2.png --start 920804400 --end 920806800 \
--vertical-label Kbyte/s \
DEF:speed=test.rrd:bytes:AVERAGE  \
CDEF:rbytes=speed,300,*,1024,* \
VDEF:total=speed,TOTAL \
LINE2:rbytes#FF0000 \
GPRINT:total:"Total transfer\: %0.2lf MB"

With VDEF i have the total for the delta between start and end.

Now i would like to calculate 'partial series' for each step..
using the example i reported before, the series i would like to have is
like this:
920804700:10
920805000:20 + 10
920805300:15 + 20 + 10 = 45 bytes between 920804700 and 920805300

and represent this as a function with a relative LINEX in graph.

How can obtain this sums?

Sorry but im not used to English mathematical language (or english at all)! :/

```