[rrd-users] Time Shift on Trend Graph

Alex van den Bogaerdt alex at vandenbogaerdt.nl
Tue Jul 2 00:12:54 CEST 2013

----- Original Message ----- 
From: "Chris Mason" <chris at netnix.org>
To: <rrd-users at lists.oetiker.ch>
Sent: Monday, July 01, 2013 12:27 PM
Subject: Re: [rrd-users] Time Shift on Trend Graph

> Hi,
> I am assuming "rrdtool last" returns the actual last time because when you
> add new data to the RRD, it rotates the RRD and the stuff that was
> previously at the beginning interval is pushed out - to always maintain 
> the
> same length and size of an RRD - you are always adding to the end?
> I am starting to conclude, after getting the feeling that I am talking to
> myself, that I can't obtain the point in my RRD when I first entered data?
> Would it not be the first non-unknown value in the data source and can I
> obtain this easily to use this to determine the start time of my graph?

Never tried it myself, but in the doc I find: rrdfirst Return the date of 
the first data sample in an RRA within an RRD

And if that does not work, You could try to use a VDEF function for this. 
Not surprisingly you would need "FIRST" again. Print it's time component.

If these two are not what you're after, then you will need to rephrase your 

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