ccddtt wrote: > rrdtool create cpu.rrd --step 3600 DS:cpufree:GAUGE:700:0:100 >RRA:AVERAGE:0.5:1:12 > >then,i use this command insert data to cpu.rrd: >/usr/bin/rrdtool update cpu.rrd N:55 > >not found data in cpu.rrd
No there wouldn't be - that is correct operation >and then,i used crond per hour run this command inster data to >cpu.rrd, also no data. Correct, there won't be. First step, have you read the documentation ? http://oss.oetiker.ch/rrdtool/doc/rrdcreate.en.html I also recommend Alex's tutorials at http://www.vandenbogaerdt.nl/rrdtool/ In particular se "Rates, normalizing and consolidating" Now, your specific problem is that RRD is doing what you've told it to do - which is not what you want it to do ! The 700 in your create command means to set the heartbeat to 700 seconds, which is considerably less than the 3600 seconds in an hour. From the documentation linked to above : >heartbeat defines the maximum number of seconds that may pass >between two updates of this data source before the value of the data >source is assumed to be *UNKNOWN*. So, you provide an update. After 700 seconds, if you haven't provided another update, then the data is assumed to be unknown. After a whole hour, you do another update. Because your updates are further apart than the heartbeat value, the previous data is no unknown and so the data up to the time of your second update is unknown. This will continue - each hour you provide an update, but each time it's been too long and so the previous data is effectively ignored. -- Simon Hobson Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed author Gladys Hobson. Novels - poetry - short stories - ideal as Christmas stocking fillers. Some available as e-books. _______________________________________________ rrd-users mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-users
