[rrd-users] Hiding data + legend in STACK graph when no data found

[Tom Payerle]

Brent Barr <b.barr <at> f5.com> writes:
 
> Since Python is my weapon of choice, I build up my graph commands as strings
in python and then send them to the
> OS to run.  In that environment, I'd just if/else each section from being
added to the string.

That's essentially what we are doing (or perhaps directly interfacing with
RRD's API), but our setup has the time span setting done much later.  I.e.,
we process all the meat of the graph from command strings, but leave options
for the web user to specify the time limits and a few other simple things (i.e.
vertical scaling, etc).

I only want to suppress the lines if there is no data over the selected time
period.  I.e. if guest VM foo was running on the container from Sep 1, 2012 to
Oct 31, 2012, it should show up in a graph of the past year
(12/13/2011-12/13/2012) but not in a graph of the past month
(11/13/2012-12/13/2012).  I don't
have the time slice at the point where I am adding lines to the graph.

Even if I did, it is more complicated than you make it sound, as my perl/python
script would have to effectively dump the rrd for that time period and check for
any valid data.

(VMware question addressed offline)