[rrd-users] Working with an old time series (1951-1989)

[Fernando Di Nucci]

I have some time series spanning from 1.1.1951 to 12.31.1989 worth to be 
analyzed and plotted using rrdtool.
To avoid negative timesamps before the epoch, I thought to shift 
everything 28 years above (1.1.1979 - 12.31.2017).
The constant 28 has been chosen to preserve such information like the 
days of the week that are the same after 28 years.

But when I try to create the archive starting at 12/31/1978 rrdtool 
(tried both ver 1.3.1 and 1.2.15) refuses to do its job complaining:

ERROR: start time: did you really mean month 283906800?

Is there a way to persuade it that yes, I really mean month 283906800 ?

Trying to start from 12/31/1979 it works, but I'd need one year before.

I can't shift 56 years because I'd end up in 2045 > 2038 with an invalid 
timestamp again.

Any idea welcome, and thank you in advance.

Fernando Di Nucci