[rrd-users] Time Shift on Trend Graph

[Alex van den Bogaerdt]

> However, from what I appear to be reading this isn't something which is
> easy to achieve as the "rrdtool first" function doesn't return the first
> non-unknown value, but the start of the RRA.

So, what about making this a two-pass solution.
First don't graph anything, just use VDEF:t1=yourdatasource,FIRST followed 
by PRINT:t1:%s
(this from memory, you may need to correct it, especially the print 
statement).

This gives you the timestamp of the first non-NaN bucket in the RRA used to 
compute this time series.

Then you use that time to create your graph.

try it and let us know please