Hi,<br><br>I'm new to rrdtool so I've been reading all the documentation and tutorials I can find. However, I have been unsuccessful with creating a database. There are a bunch of weather stations I would like to watch and record the last time their data is updated. I have a python script which looks at the data and determines the time of the most recent data. This time is typically 10-30 minutes behind the actual time. I run the script every 10 minutes to update a web page that displays the time of the most recent data for each station.
<br><br>What I would like to do is add to this script a call to rrdtool.update() which will send a unix timestamp to be saved in now's slot.<br>Is this the correct way to create the rrd?<br><br>rrdtool create test.rrd
-b 1177916700 --step 600 DS:updated:COUNTER:720:1177900000:U RRA:LAST:0.5:1:105120<br><br>That is, start at Apr 30 12:05AM. Create PDP 'updated' every 10 minutes. Allow 12 minutes between database updates. Keep the last 1 values and keep 105120 of them.
<br><br>Does this make sense? The RRA is still a bit confusing to me. I will only have one sample every 10 minutes and I would like to keep that one sample as the PDP for that 10-minute slot. rrdtool can handle much more complicated situations than this, but it seems like this very simple situation is not so easy to configure.
<br><br>The goal is to make graphs that show when the stations stopped updating at expected times, i.e. there would be a flat line since the 'updated' time didn't increase from PDP to PDP. Eventually, I want to color the area under the line according to some threshold, such as "red if the station hasn't updated for 6 hours."
<br><br>Any suggestions are welcome.<br><br>Thanks,<br>Grant<br>