[mrtg] heartbeat

[Alex van den Bogaerdt]

On Wed, Jun 27, 2007 at 12:22:15PM +0200, Matthias Laug wrote:

> I want to update my rrd database once a day with 24 values. So one for each
> hour.
> 
> so I created this:
> 
> rrd create --step 3600 myrrd.rdd DS:cputime:Counter:??????:U:U
> [...]
> 
> what should be the value for heartbeat, so that my values are not set to
> unknown, or does the update overwrite such settings?

The way it is supposed to work (or so I think):  The current update
time, minus the last update time, should not exceed the heartbeat
time.

This translates to: if you want to update once a day, on exactly
the same time each day, you need to set heartbeat to
25 * 3600 = 90000.  Why 25 hours?  Because of daylight saving.

HTH
-- 
Alex van den Bogaerdt
http://www.vandenbogaerdt.nl/rrdtool/