[rrd-users] Monthly graph fetches data from yearly RRA instead of monthly one

[Simon Hobson]

Juma wrote:
>Then I call rrdtool graph with --end now --start end-${interval} options,
>where ${interval} is the appropriate one for every graph.

I always massage the end time to be an integer multiple of the required step :
x = now
e = x - ( x % step )

or if doing integer arithmetic (as in Bash scripting), just :
e = now / step * step

And then make sure that the period of the graph, ${interval},is an integer multiple of step.