[drraw-users] start/end time on a DEF

[Christophe Kalt]

Hi,

On Aug 12, Cattell, Michael wrote:
| I've been using drraw for some time now and find it a very useful companion to Gangila and other rrd related data.
| Of late, I've been writing some custome rrd graphs that use SHIFT so that I can compare a few day's worth of data for one data source overlaid.
| 
| This is particularly nice if you want to see what yesterday's CPU or I/O is like compared to today.
| 
| Here is an example of how I typically do it.  This is an example I copied from the internet, but the syntax is correct.
| 
| 
| 
| rrdtool graph day_c.png \
| 
|         --end midnight \
| 
|         --start end-86400 \
| 
|         --upper-limit 400000 \
| 
|         --lower-limit -100000 \
| 
|         DEF:a=test.rrd:ds0:AVERAGE \
| 
|         DEF:b=test.rrd:ds0:AVERAGE:start=end-86400:end=midnight-86400 \
| 
|         LINE:a\#00CC00:a \
| 
|         LINE:200000 \
| 
|         SHIFT:b:86400 \
| 
|         LINE:b\#FF0000:b:STACK
| 
| With 2.2a5, there's SHIFT and that's way cool.  However, I have been able to figure out how to pull off the start/end times that are on the DEF and that seems like the only way to make sure the SHIFT shows data after the offset is in effect.
| 
| Any ideas on how I can do this with DRRAW?

My guess is that you can't.  Unfortunately, i missed your
email when i was working on drraw earlier today.  I'll have to
look at the docs for RRDtool to sort it out, but the way i
read and understand the above, it seems like the start/end
DEF modifiers and the SHIFT are redundant.  Either one without
the other doesn't do anything, does it?  i find that odd, but
if that's the case, it should just be a matter of teaching
drraw how to deal with this.