On Mon, Apr 26, 2010 at 11:59 PM, Simon Hobson <[email protected]> wrote: > Canhua wrote: > >> I create a rrd, the info is as follows: >> _______________________________________ >> filename = "mailrelay1.rrd" >> rrd_version = "0003" >> step = 300 >> last_update = 1272293941 > > ... >> >> as you can see the step is 300 seconds, and I update the rrd every minute, >> but I get NaN when I "fetch" from the rrd > > How long did you enter data for ? > Which RRA did you fetch ? > > Each data point (where primary or consolidated) will not be available until > there has been atr least one update after the period ends. For a primary > data point, this will be after an integral number of "step" seconds from > unix epoch has elapsed - so that means every 5 minutes (ie n:00, n:05, n:10, > ...). For consolidated data points, it means integral multiples of > (step*pdp_per_row) from unix epoch (eg if pdp_per_row were 3, then that > would mean on the hour, quarter past, half past, and quarter to). In your > case, pdp_per_row is 1 so you should get data available when you do an > update that is on or past each five minute step. > > Ie, if you update at 00:04:59 then you have not completed the step and it > will be NaN. If you update on or after 00:05:00 then it is and data will be > available for that step. > > In each case, you must have entered enough data for the sample period to be > known. In your case, if you don't enter data for more than 10 minutes (600s) > then the data becomes unknown. > > In your dump, I see unknown_sec = 241 - that suggests you've only just > started entering data - give it another 5 minutes and it should be OK.
I enter data every minute by cron, and I fetch the AVERAGE RRA(I have only one RRA actually). My cron have run many many hours and even days, and I still 'fetched NaN. _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
