[rrd-users] Stacking at Infinity

[Chris Mason]

Hi,

I am graphing class based interface statistics using RRDTOOL and I am
trying to find a way to graph errors on the same graph. At the moment
if I detect errors I am highlighting the background with an AREA using
the INF or NEGINF functions. This works fine and I can see if I had
errors during the period. An example of this is below:

http://netnix.org/example.png

However, I would like to enhance this further to give some indication
of the class or classes that dropped traffic.
For each of the classes I have tried to do the following:

CDEF:DSxH=DSx,0,GT,INF,UNKN,IF
LINE3:DSxH#xxxxxx

This will draw a line at INF using the classes colour if errors were
detected in that class. If multiple classes have drops then the line
will get overwritten with the later colour. I could use transparency
but then it is usually difficult to determine the colours. I have
tried stacking, but it doesn't like stacking on top of infinity which
sort of makes sense.

If I had drops in two classes then I would like to see 2 lines stacked
on top of each other in different colours at infinity or negative
infinity for inbound drops.

Is this possible or am I trying to push it to hard with my graphing
requirements?

Thanks,
Chris