[rrd-users] Invalid RPN expression

Alex van den Bogaerdt alex at vandenbogaerdt.nl
Wed Oct 9 01:28:04 CEST 2013

> I am trying to sort out an invalid RPN expression, but I am a bit confused
> as it works on other graphs using the same class to generate the rrdtool
> command.
> Does anyone see anything obvious from the command below?

I don't see anything obvious, it looks like it should work.
Usually it helps to reduce the case to a simpler one.

Look for similar characters. Example:  l (el) vs. 1 (one) is something
that I found in another problem.
Look for hidden characters, perhaps not visible in your editor but present
in the file.

> rrdtool graph -w 400 -h 175 -l 0 -t "Load on collectd.penton.com" -v
> "System Load" -s e-86400
> DEF:min_9f24bee8_raw=/rrd/file/collectd.penton.com/load/load.rrd:shortterm:MIN
> CDEF:min_9f24bee8=min_9f24bee8_raw,1,*
> AREA:min_9f24bee8#ffffff

Does this work? If so: did you type a new script by hand? If so: does it
still work when you take your script and remove the lines which I also
If it still works, remove less and try again, until you have found the
problem area. Then you can probably spot the error.

An editor which can highlight stuff may also help, even windows notepad's
find function may be of help.  Or use sed, perl, awk, whichever tool works
best for you.  If all else fails, I would find the smallest example that
still gives me the error and then I would make a hexdump of the file ...

And, just out of curiosity, why do you multiply by 1, it just seems to
waste resources?


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