[rrd-users] How to find first valid dp in rrd - repost - where are the experts?

[Karl Fischer]

Hello,

since there was no answer to my last post, I'm trying again.
Where are the experts?

Is there a good way to find the first valid (not UNKN) datapoint in rrd?

rrdtools first doesn't quite do what I expected.
Instead it gives you "rrdtools last" - rrasize.

Example:

 --step=1
 DS:loadavg:GAUGE:10:0:U
 RRA:AVERAGE:0.5:1:259200     # 3 days
 RRA:AVERAGE:0.5:10:259200    # 30 days
 RRA:AVERAGE:0.5:60:259200    # 180 days
 RRA:AVERAGE:0.5:600:259200   # 1800 days

If I have created a rrd like this and I started to use it a week ago,
I'm looking for a way to find out when that fist value was entered
into the rrd. Instead of telling me the first 'valid' DP in that rrd,
"rrdtools first file.rrd" tells me 'now - 3 days' and
"rrdtools first file.rrd --rraindex 3" tells me 'now - 1800 days'
What I would like to get is that point in time a week ago when I
entered the first value.

any ideas?

many thanks

- Karl